Monday, February 28, 2011

Malaria Proof Mosquitoes

Time magazine recently named the development of that have been genetically modified to resist malaria as one of the 50 best inventions of 2010 and gave it the No. 1 spot in the health-and-medicine category.

Now the goal is to make the altered mosquitoes hardier than native varieties, which they could someday supplant in nature throughout the world.

"Our hope is to release them and drive the gene through the population," said professor Shirley Luckhart, a leader in the joint effort between scientists at UC Davis and the University of Arizona.

From an article last week, Researchers work to create malaria-proof mosquitoes, in The Republic Newspaper.

An alternative approach that I very briefly mentioned in class is to use knockout genes to drive certain mosquito species to extinction. This approach was described by Olivia Judson in a New York Times Op-Ed piece in 2003: A Bug's Death.

There's no shortage of ideas. So why are so many people still suffering from malaria and why do so many children die?


Does Malaria come from Great Apes?

I found a recently published article (September 2010), which presents information on research regarding the evolution of malaria. Scientists have concluded that the parasite most likely originated in the lowland gorillas, who may be infected with a "genetically identical microbe." Amazingly, researchers also believe that the parasite crossed the species border with just one mosquito bite--one bite is responsible for the outbreaks and epidemics of the disease!
Furthermore, scientists are hopeful as to the benefits of knowing the source of the parasite. They believe that with this new information they may be better able to understand and treat the disease. The article uses HIV as a parallel study, because knowing that HIV originated in primates has allowed for further research into the nature of the disease.
Finally, the researchers believe that the parasite does not have as negative an effect on the gorillas as it does on humans.

http://www.independent.co.uk/news/science/evolution-of-malaria-is-traced-back-to-greatest-ape-2087035.html

Pseudacteon Flies

This post is a little late, as it concerns a topic that we discussed last week, but it's another really interesting example of how a parasite can alter host behavior. Female Pseudacteon flies quickly inject an egg into the neck region of an ant through a rapid attack. The larva moves into the head cavity of the ant, where it eventually eats the brain of the ant (and therefore kills it). The head of the ant falls off, and the organism continues to develop inside the detached head. Once fully developed, the organism leaves the head as an adult fly.

http://www.biocontrol.entomology.cornell.edu/parasitoids/pseudacteon.html

Sunday, February 27, 2011

Transgenic fungi combat malaria

A day early for our malaria week, but too topical not to mention, is this report today on ScienceDaily about the use of transgenic fungi to combat malaria and other diseases. The ScienceDaily report is based on a paper out in the journal Science this week: Development of Transgenic Fungi That Kill Human Malaria Parasites in Mosquitoes.

New findings by a University of Maryland-led team of scientists indicate that a genetically engineered fungus carrying genes for a human anti-malarial antibody or a scorpion anti-malarial toxin could be a highly effective, specific and environmentally friendly tool for combating malaria, at a time when the effectiveness of current pesticides against malaria mosquitoes is declining.

The research team found that compared to the other treatments, spraying mosquitoes with the transgenic fungus significantly reduced parasite development. The malaria-causing parasite P. falciparum was found in the salivary glands of just 25 percent of the mosquitoes sprayed with the transgenic fungi, compared to 87 percent of those sprayed with the wild-type strain of the fungus and to 94 percent of those that were not sprayed. Even in the 25 percent of mosquitoes that still had parasites after being sprayed with the transgenic fungi, parasite numbers were reduced by over 95 percent compared to the mosquitoes sprayed with the wild-type fungus.

Saturday, February 26, 2011

Parasite Rex

If you'd like to read more about parasites that are capable of changing host behavior than Carl Zimmer's book, Parasite Rex, contains several chapters devoted to them. Zimmer is an excellent writer and this book is a very entertaining read. You can also check out his science blog, The Loom, where he frequently talks about parasites.

Imagine a world where parasites control the minds of their hosts, sending them to their destruction.
 
Imagine a world where parasites are masters of chemical warfare and camouflage, able to cloak themselves with their hosts' own molecules.

Imagine a world where parasites steer the course of evolution, where the majority of species are parasites.

Welcome to earth.

Friday, February 25, 2011

Friday videos

If you were unable to make class today here are two videos you missed. Plus a bonus video at the end if you already saw these two.





The last video shows a horsehair worm (Nematomorpha) exiting from its host.  The larvae live inside the insect and absorb nutrients directly through their skin. The adults are mostly free living in freshwater or marine environments

In Spinochordodes tellinii, which has grasshoppers and crickets as its larval host, the infection acts on the insect's brain and causes it to seek water and drown itself, thus returning the nematomorph to water. They are also able to survive the predation of their host, being able to wriggle out of the predator that has eaten the host! This manipulation of the host is documented here: Do hairworms (Nematomorpha) manipulate the water seeking behaviour of their terrestrial hosts?

office hours survey

I was contacted by some researchers at UCSB that want to do a survey of student attendance in office hours. If you want to participate, I'm copying the email and the link below. You are in no way required or expected to participate, and if you do it is anonymous.

------------------------------------------------------------------------
My student group (Community Research Group @ UCSB) and I are working on research investigating how office hour attendance is related to undergraduates' grades. EEMB 40 was selected as part of the random sample for this project. It would be extremely helpful to us if you could take 3 minutes (it really is that quick) to fill out the survey and to forward the undergraduate-specific version (also extremely brief) to the students in this class. If you would like to see the content of the undergraduate survey, just open the link below. Of course, all responses are collected anonymously.

Please forward this address to the undergraduate students in this class via email: https://www.surveymonkey.com/s/GRVCT37

We hope this project will demonstrate the importance of office hours to undergraduate success, and illuminate factors that prevent students from attending. If you have any questions about any part of the research (or about Community Research Group), please feel free to contact me.

Community Research Group is an undergraduate-run research team advised by Dr. Paolo Gardinalli (UCSB Social Science Survey Center).

Thank you for your participation!

Ilya Altshteyn
President
ilya01@umail.ucsb.edu | 858.349.9773

Thursday, February 24, 2011

No more litter boxes??

Someone in class talked about a cat toilet. here are a few options for a litter free home:


The Litter Kwitter-Cat Training System.

Richell Paw Trax Cat Potty

And my personal favorite...

Activeion

So here we have another product that kills 99.9% of germs, but this one is a bit different from the rest. It has one ingredient, and thats good old H2O. This Activeion spray bottle ionizes water by sending it through an ion exchange membrane where the water is separated into a mixture of oxygenated positively and negatively charged nano-bubbles. The water stays in this state for about 45 seconds before returning to its normal state. The ions lift the dirt off the table and make it easier to clean so no residue is left, water or dirt. Also, it creates a small electrical field which can cause certain bacterium to become agitated and burst. Watch the video for more. It seems like it could be useful in hospitals or other places where alot of germs are present and I feel like its methods would be less likely to create resistant drugs since its merely ionized hydrogen and oxygen Heres the link to the website with a video that clearly demonstrates its method of action

Activeion Spray Video

A Positive of Protozoa




Protozoa, such as Toxoplasmosis gondii (the infectious agent of toxoplasmosis), may appear to be solely malignant organisms that infect a large portion of the worlds population, however, scientists working for Massachusetts-based company Petrel Biosensors have found an extremely beneficial use for the nasty single-celled organisms: testing water quality.

Sure we have modern methods to test water quality, however this newly developed technology, called Swimming Behavioral Spectrophotometer or “SBS”, is able to accomplish that task in a much cheaper and faster way than our current technologies.

The system, designed by Scott Gallager, detects toxins in the water supply through analysis of how the protozoa move throughout the sample. Most toxins are known to disrupt calcium transport and since the hair-like cilia responsible for protozoan motion are sensitive to aqueous calcium content, the presence of toxins can cause an erratic and irregular response in the microorganism (see original article on circleofblue.com)

This new method has a variety of applications including water monitoring for public drinking water supplies, for military units in the field, and for industrial waste discharge. Because the SBS acts as a “real-time” test, the quality of the water can be determined very quickly and appropriate action can be taken immediately. And at $1 to $2 per test, Gallager’s protozoan-dependent method presents a cheap and affordable system which rivals laboratory analyses ranging from $50 to $250 per evaluation.

However, in order to get his SBS technology moving forward, Gallager predicts that the company will need at least $2 million, on top of the $1 million Department of Defense grant already received, to get his new technology distributed to the world.

All cats are not created equal

Can I "catch" toxoplasmosis from my cat?
Because cats only shed the organism for a few days in their entire life, the chance of human exposure is small. Owning a cat does not mean you will be infected with the disease. It is unlikely that you would be exposed to the parasite by touching an infected cat, because cats usually do not carry the parasite on their fur. It is also unlikely that you can become infected through cat bites or scratches. In addition, cats kept indoors that do not hunt prey or are not fed raw meat are not likely to be infected with T. gondii.
In the United States, people are much more likely to become infected through eating raw meat and unwashed fruits and vegetables than from handling cat feces. 
From Cornell Feline Health Center's Toxoplasmosis brochure.


On the other hand because cats are the definitive host ONLY cats shed oocysts. This means that all infected meat, fruit and vegetables must ultimately have been contaminated from oocysts shed in cat faeces. Even though cats may only shed oocysts for a short while they can last a long time in the environment. Your domestic kitty may not be responsible for the environmental oocyst contamination but some kitty is....

Wednesday, February 23, 2011

Nigerian Rinderpest: A Huge Loss







Between the years of 1980 and 1984, and especially in 1983, Rinderpest affected cattle in Nigeria very severely, affecting not only the health of cows, but the country’s economy, forcing many cattle farmers out of the trade. In this post I will discuss the 1983 epidemic.

Lesser breakouts of the disease caused the death and slaughter of over 10,000 cows before being put under control. (One theory is that infected herds from Cameroon were introduced as their owners tried to escape the inevitable slaughter of their herds.) During the dry season of 1983, coincidentally, after huge brush fires had diminished grazing area, cattle herders were forced to drive cattle to a limited amount of areas in search of water. Because of the fires, malnutrition was also a problem at this time, and when combined with the density of cows, led to a huge outbreak.

In 1982, a combined 826 cows died in Nigeria as a direct result of Rinderpest, and from slaughters aimed towards preventing its spread. In 1983, this figure skyrocketed as a result of combined factors. How high? In 1983, this number surpassed 418,000. Vaccine use was implemented, (nearly 9 million cows were vaccinated) but not in time to prevent the ENOURMOUS cost to the country of Nigeria.

When all areas of profit loss, preventative, slaughter and other costs were combined, this epidemic took a huge toll on the country. About 304 million dollars in cattle were lost, 140 million dollars lost as a result of active cattle infections, 100 million lost in disease surveillance, 90 million lost in working hours, 303 million lost in cattle replacement costs, and an astounding 577 million in losses due to reduced value of Nigerian cattle, the need for important milk and meat, and other national costs. Overall, the estimated monetary loss for Nigeria totaled 1.5 billion dollars.

Toxoplasmosis as a Cultural Determinant?

According to a blog that I found, a recent study seems to suggest that Toxoplasmosis can have an effect on human cultures. As we discussed in class today, toxoplasmosis levels vary from country to country, correlating with levels of exposure and risk factors such as the consumption of undercooked meat. Also as we discussed today, toxoplasmosis can have effects, albeit small, on human behaviors. Therefore, this blogger suggests that varying cultural behavior may be at least partly affected by toxoplamosis infections. This is not to say that the blogger thinks that all cultures are completely determined by toxoplasmosis affects, but I think that it is an interesting hypothesis. I'll let you decide if you think that it's a sound judgement.

http://scienceblogs.com/notrocketscience/2008/10/toxoplasma_the_brain_parasite_that_influences_human_culture.php

Toxoplasmosis and the French

Based on the data that toxoplasmosis is present in 90% of the population in France and Professor Latto's not so subtle remark that toxoplasmosis could be responsible for certain "behavioral problems" associated with French people, I decided to try to do a little research into this possible correlation. I did not find much, but on Webster's extended online dictionary definition of toxoplasmosis, I found a very interesting quote attributed to one Kevin Lafferty:

"In populations where this parasite is very common, mass personality modification could result in cultural change. [Variations in the prevalence of Toxoplasma gondii] may explain a substantial proportion of human population differences we see in cultural aspects that relate to ego, money, material possessions, work and rules."

I took the liberty of bolding a few words that might assist Professor Latto's hypothesis about French people. I wish there was more information on this subject, and maybe certain French stereotypes are not really their fault (if you do not want to blame them on eating undercooked meat). Oh well, c'est la vie.

Toxoplasmosis passed to kittens?


Today in lecture, someone asked a question about whether a cat infected with toxoplasmosis can/will pass the disease along to its kittens...here are some things a veterinary site I found had to say about the subject:

- Once cats become infected with Toxo they will always have it, but they will only pass it in the stool for a brief time just after they are first infected. Most cats only pass the organism in the stool ONCE in their lives and usually when they are kittens. The exception to this would be if an older cat got another disease that suppressed their immune system (such as feline leukemia or feline aids).

- How do we prevent this? That is a tough problem. Many folks recommend getting rid of your barn cats. The problem is that stray cats passing through your barn or pasture can also shed the organism. Other people have advocated having a few, neutered barn cats. These cats are not going to be having kittens (the age most likely to shed the parasite) and they are going to hopefully chase off any stray cats that come around. The most successful method of preventing this is to keep the feed and the hay in areas where cats cannot get to it...and practice good hygiene!

Behavioral Effects of Toxoplasmosis

Toxoplasmosis appears to manipulate personality by the same adaptations that normally help the parasite complete its life cycle. A study on rats with a latent infection, the rat's behavior alters so that it becomes more active, less cautious and more likely to be eaten by a cat, where the parasite can complete its life cycle. Tests on humans suggest that toxoplasmosis is associated with different, often opposite, behavioral changes in men and women, but both genders exhibit guild proneness. The study also found that countries with high toxoplasmosis prevalence had a higher neuroticism score and western countries with high prevalence also scored higher in the neurotic dimension of male sex roles and uncertainty avoidance.


http://www.news-medical.net/news/2006/08/03/19237.aspx?page=2

Waterborne toxoplasmosis

Just what we need - another way to get infected by Toxoplasmosis.

Waterborne toxoplasmosis – Recent developments
Humans become infected with Toxoplasma gondii mainly by ingesting uncooked meat containing viable tissue cysts or by ingesting food or water contaminated with oocysts from the feces of infected cats. Circumstantial evidence suggests that oocyst-induced infections in humans are clinically more severe than tissue cyst-acquired infections. Until recently, waterborne transmission of T. gondii was considered uncommon, but a large human outbreak linked to contamination of a municipal water reservoir in Canada by wild felids and the widespread infection of marine mammals in the USA provided reasons to question this view. The present paper examines the possible importance of T. gondii transmission by water.

Tuesday, February 22, 2011

Possible canine distemper outbreak in Mt. Angel



The Mt. Angel Police Department has recently received numerous complaints about sick raccoons in the area. Canine distemper is highly contagious. It is a viral disease affecting raccoons, coyotes, skunks and un-vaccinated dogs. Distemper symptoms include nose and eye discharge, rough coat of hair, emaciated appearance and unusual behavior which can include disorientation and aimless wandering.

So far 6 raccoons have been disposed of, one of the animals died before the police had arrived. After the Oregon Department of Fish and Wildlife was contacted it seems that distemper is the likely cause of the illness inflicting raccoons in this area. While some believe that rabies could be the cause, especially since they have some similar symptoms, there are some main differences. The main difference is that rabies is able to be transmitted to humans whereas canine distemper cannot.

The main advice that seems to be spreading around is to not feed their pets outside since unvaccinated dogs can catch the viral disease if infected raccoons use their food or water dishes. It is also highly encourage to not feed or approach raccoons since their behavior can be potentially dangerous.

http://www.statesmanjournal.com/article/20110207/UPDATE/110207024/1062/Mayor-s-censure-spurs-discussion/Canine-distemper-suspected-raccoons-Mt-Angel?odyssey=mod_sectionstories

Flu shot scare or HOAX?


One of my friends showed me this video over the weekend. Desiree Jennings claimed to have contracted a highly rare case of the neurological disorder called "dystonia." After a routine flu shot, she claims to have suffered problems with speech, with walking, with eating, etc--unable to perform any of these normal tasks without seizing uncontrollably. However, after this story became such a hot topic in the news during a period of heightened vaccination scares, news teams discretely followed Desiree to track any improvements...and look what they found!


http://www.youtube.com/watch?v=QOmNuIYFD7g&NR=1

click on this youtube link for the surprising video!!

Expedited Partner Therapy

Yesterday's LA Times had an article about some new programs to help combat sexually transmitted disease.

They mainly talk about the 'I want the kit' program that supplies free in-home testing kits for three of the most commonly reported STDs, however they also mention the Get Yourself Talking, Get Yourself Tested program and the more controversial  Expedited Partner Therapy  (EPT) which allows those who test positive for certain sexually transmitted diseases to take home antibiotics for up to three partners without a health care provider first examining the partners.

Although this is not legal in all states (see the map at the CDC website) the CDC has reviewed the evidence and concludes that EPT is a useful option particularly for treatment of male partners of women with chlamydial infection or gonorrhea.

(Graphic is from inSPOT a website that allows you to send electronic postcards anonymously or from your email address to your sex partners to inform them that you have an STD).

Monday, February 21, 2011

Robert Koch and Rinderpest

The German physician and microbiologist Robert Koch is most famous for developing the germ theory of disease and for proposing that ‘one germ causes one disease- every disease has its specific germ’.

Koch and his pupils found the organisms responsible for tuberculosis, anthrax, diphtheria, typhoid, pneumonia, gonorrhoea, cerebrospinal meningitis, leprosy, bubonic plague, tetanus, and syphilis, among others.

In 1896 Koch was brought to South Africa by the Cape Government to investigate and find a cure for cattle plague, or Rinderpest, which had broken out during the last decade of the 19th century. The epidemic affected most of southern African, but it hit the Transvaal and Northern Cape particularly hard.

Although he did not identify the cause of this disease, he succeeded in limiting the outbreak of it by injection into healthy farm-stock of bile taken from the gall bladders of infected animals. He announced the discovery of his vaccine on 10th February 1897.

Sunday, February 20, 2011

The Panic Virus

I was going to blog about the release of a new book called 'The Panic Virus' - that has received some good reviews when I noticed that today's Doonesbury cartoon also takes on the Jenny McCarthy issue. As a former playmate Boopsie has some harsh words for Jenny and the damage she has caused to the playmate brand. The full strip is here at Slate.com.

From the blurb for The Panic Virus:

In 1998 Andrew Wakefield, a British gastroenterologist with a history of self-promotion, published a paper with a shocking allegation: the measles-mumps-rubella vaccine might cause autism. The media seized hold of the story and, in the process, helped to launch one of the most devastating health scares ever. In the years to come Wakefield would be revealed as a profiteer in league with class-action lawyers, and he would eventually lose his medical license. Meanwhile one study after another failed to find any link between childhood vaccines and autism.

Yet the myth that vaccines somehow cause developmental disorders lives on. Despite the lack of corroborating evidence, it has been popularized by media personalities such as Oprah Winfrey and Jenny McCarthy and legitimized by journalists who claim that they are just being fair to “both sides” of an issue about which there is little debate. Meanwhile millions of dollars have been diverted from potential breakthroughs in autism research, families have spent their savings on ineffective “miracle cures,” and declining vaccination rates have led to outbreaks of deadly illnesses like Hib, measles, and whooping cough. Most tragic of all is the increasing number of children dying from vaccine-preventable diseases.

Parasite biology indicates a land–sea connection


Investigation into the processes promoting T. gondii infections in sea otters may be our best opportunity to understand terrestrial parasite flow into the coastal marine system. In the absence of evidence that the high number of sea otters infected off the coast of California can be attributed either to the ingestion of prey containing tissue cysts or vertical transmission, the most likely source of infection is exposure to the environmentally resistant, infective oocysts of T. gondii, which can survive for months or years in contaminated soil, freshwater or seawater. Toxoplasma gondii oocysts may remain infective despite water chlorination or sewage processing... Furthermore, the infectious dose for some species may be as low as one oocyst.

Several studies have demonstrated that oocysts and cysts of pathogenic protozoa are concentrated by clams, mussels and oysters during filter-feeding activity. Thus, raw shellfish could serve as a source of pathogenic protozoal infection for both marine mammals and humans. To maintain normal body weight and meet metabolic demands, sea otters consume approximately 25% of their body weight each day in invertebrate prey, such as mussels. Other possible modes of T. gondii infection could be by the ingestion of oocysts in seawater, by grooming and ingesting oocysts collected on their fur or by ingestion of oocysts that are on or in prey other than bivalves...however, these hypotheses require further investigation!

Saturday, February 19, 2011

Toxoplasmosis in Humans


It seems that toxoplasmosis transmission is not only a problem for seals, but also for humans, who can fairly easily come into contact with the disease. For example, people can accidentally ingest the harmful parasite through normal practices such as gardening. If an infected cat's feces are in the soil and a gardener does not wash his or her hands before eating, the person can accidentally swallow the parasite. People can also come into contact with the parasite while cleaning their cat's litter box and failing to wash their hands afterward. So if you have a cat make sure that you always wash your hands after cleaning the litter box or do things outdoors where your cat may have been roaming around!
Humans can also become infected through contaminated or undercooked food products, and, less commonly, through blood transfusion or mother-to-child transmission.

Eradicating Rinderpest

A short 4 minute video that explains a little more about the eradication of Rinderpest.

Scientific innovation, international collaboration and investment from donors, such as/including the UK's Department for International Development, supported the work of teams of community health workers wherever rinderpest attacked cattle. Two of the scientists involved, Dr John Anderson and Dr Michael Baron, explain what has been achieved and how.

Friday, February 18, 2011

After the Rinderpest

Whilst there is, of course, a death metal band called Rinderpest, with a song called Rinderpest, I couldn't make much headway with the 'lyrics'. Let me know if you have better luck.

More interestingly there is a South African musician who has a whole album about the Rinderpest epidemic that devastated Africa.

The Scene is the Cape Colony border, late 19th century, a terrible plague, the Rinderpest (rather like Foot & Mouth), has decimated the livestock and lives of the Boers, Brits and Amaxhosa alike. The infected animals have to be piled in pits and burned. The land is covered in smoke and weeping.

It's not easy to find but you can download an mp3 of the title song , After the Rinderpest, from the Last.FM website.
After the Rinderpest
 
There’s a wicked wind on the smoking ground
All out hopes and dreams, we had to burn them down.
And our poisoned wells took our first and best
Gave our childrens’ lives to the Rinderpest.
 
Sent our youths away to be militarized
And we couldn’t see into their empty eyes.
Would you have the strength, if they confessed
To what they saw, in the wilderness.
 
With a burying pit full of burning beasts
With the crimson coals of the heat beneath.
Holding out our hands to be cauterized
But the Rinderpest left us paralyzed.
 
And a tattooed child full of battle scars
With a heart of iron, hammered hard.
Do we act surprised, as though we never knew
What the sulphur air would have done to you.
 
There are bands of us that have survived
And all we have is how we live our lives.
As we struggle on, we must not forget,
Just what we learned, from the Rinderpest.

New Zealand Blood Donation


Starting in 2000, the New Zealand Blood Service banned donations from anyone who lived in Britain, France, or Ireland for six months or longer during 1980 and 1996. This ban was put in place because of the risk of donated blood helping to transmits vCJD.

British scientists have recently developed a prototype blood test which is 100,000 times more sensitive than the previous test. This test is able to detect tiny amounts of vCJD-causing particles(prions).

The lead researcher, Graham Jackson, said that even though larger studies are going to be needed to confirm its effectiveness, the tests could in the future allow doctors to screen whole populations for vCJD. If this test is truly effective it could clear the way for thousands of residents of New Zealand to give blood.

Thursday, February 17, 2011

Chronic Wasting Disease


A new form of TSE (transmissible spongiform encephalopathy) that is becoming a main concern in the United States is Chronic Wasting Disease, or CWD, which is becoming more prevalent in wild game such as deer, elk, and moose throughout the US.

The disease is related to BSE, or “Mad Cow” Disease, and therefore concern of it being transmitted to humans through the consumption of wild game is growing as more and more deer and elk are found to be infected with the prion-caused disease.

Deer and elk infected with CWD suffer loss of body condition and control, behavioral abnormalities and eventually death. While there have been no confirmed cases of CWD among humans so far, the fact that the disease has spread from endemic areas of northeastern Colorado, southeastern Wyoming and southwestern Nebraska to numerous places across North America is a source of concern for wildlife managers. (Map of CWD cases in wild deer and elk throughout the USA)

The origin of CWD is unknown, mainly because it occurs in wild game that are not closely monitored for infectious diseases. One theory suggests that CWD is derived from scrapie in sheep.

Also unknown among experts is the method by which CWD is transmitted from deer to deer. Theories suggest it may be passed through contact with feces, urine, or saliva but another theory suggests maternal transmission from mother to fetus.

Hopefully scientists can figure out exactly what causes the disease and how it is transmitted amongst wild game in case the disease does become transmissible to humans in the years to come.

Prions and memory

As we now know Prions are really just misshapen forms of a normal protein that occurs in everyone. This raises the important question of just what these 'normal' prions do in the body. One suggestion is that they may be involved in the maintenance of memory:  Prions as adaptive conduits of memory and inheritance (in yeast) and Hippocampal synaptic plasticity in mice devoid of cellular prion protein (in mice). From the first paper:

Any molecular basis for long-term memory formation must explain its endurance (for many years) despite the continuous turnover (every few hours) of the proteins that might encode them. Information storage despite molecular turnover is traditionally explained by autophosphorylation loops, self-sustaining feedback loops in complex signalling networks, or transcription factors that stimulate their own synthesis once they cross a threshold concentration. The conformational replication of prions provides another durable form of molecular memory. Moreover, as is clear from studies in yeast, prion conformations are not usually toxic. Incredibly, prion-based mechanisms might operate in individual neuronal synapses to maintain their growth and contingent long-term facilitation.

Fungal prions are proving to be a very useful model organism for studying mammalian prions since numerous forms have now been identified, they are infectious and self-replicating like mammalian prions but they do not appear to be associated with disease in fungi. In fact there are several suggestions they may have aided fungal evolution.

Mad cow disease-- good for grassland birds?


Mad cow disease is good for grassland birds: Exploring novel socioeconomic links to wildlife ecology

Results/Conclusions from their experiments:

We found support that included a one-year lag between each step wherein: 1) imports increase and exports decrease in response to BSE outbreaks in the previous year, 2) the hay harvest in North America is then reduced two years after the outbreak as fewer cattle remain in North America, which ultimately yields 3) a positive response in grassland bird populations in the year after hay harvest reduction – three years after the BSE outbreak. Our results illustrate the importance of socioeconomics in conserving North American avifauna – such knowledge will allow us to improve management recommendations and better predict future periods of adversity to bird populations.

Wednesday, February 16, 2011

HealthMap

As Professor Latto discussed a few weeks ago in lecture, virtual maps (such as "Google Maps") can be very helpful in tracking disease outbreaks. I recently discovered a resource called "HealthMap," which was created in 2006. According to a blog article, HealthMap currently "mashes up with a variety of sources including ProMED-mail, the World Health Organization, EuroSurveillance, and Google News to give way to a useful world health maps mashup application."

If you look at the map, you can locate any area in the world and see if an outbreak has been noted. Below the map, you can see outbreak alerts from the past three days. This seems like a great way to stay informed about world health issues!

Mad Cow Disease in Art


Despite the seriousness of Mad Cow Disease, many cartoonists have found it to be a prime subject for their art. If you need a break from the humorless aspects of the disease, take a look at some of these fun cartoons!

"Sacred Cow"
"Mad Children's Disease"
"Bird Flu"
"Mad Farmer"
"Mootation"
"Revenge of the Mad Cow"
"Mad Cow Disease"
"It's the US"
"Bird Flu" (2)

Mad Cow Disease in 1990


In the first article ever published in The New York Times about Mad Cow Disease, journalist Sheila Rule describes the symptoms of the infection and explains that a fear was arising that the disease "might spread to humans." Furthermore, Members of Parliament "announced a wide-ranging investigation into the ailment."

It is interesting to look back and see the claims made by the British Government at this time. Not only did they insist that "beef is safe to eat," but they campaigned "to show that there is no reason to believe that it is a danger to humans" as well.

According to the article, public fears "were fueled by the death of a pet cat suffering from symptoms of the virus." When people discovered that the disease was not only prevalent in cows, they began to worry about their own abilities to contract the disease.

Despite the public fear, "Government's chief medical officer, Sir Donald Acheson, said in a statement that he had checked with leading scientific and medical experts and that British beef was safe." Considering the outbreaks in humans over the following few years, it appears as though Sir Acheson was not very well-informed!

New Cases of BSE in US Raises Questions About Testing

A third confirmed case of mad cow disease in the US points out the difficulty of preventing, and even detecting, these cases under the current voluntary testing system. This testing method also makes it more troublesome to convince meat markets overseas that American beef is safe given that there is no guarantee that the beef exported is BSE free. Since this case has been confirmed, the US Department of Agriculture has been trying to track down the cow in question's herd of origin and offspring, pointing out flaws in the current testing system because this information is necessary in determining risk to the population. There is currently a fight to create a mandatory system so that there are no doubts about the safety of US beef and therefore stopping the bans on US meats when these isolated cases are identified.






http://www.csmonitor.com/2006/0315/p02s01-uspo.html

Caution might be exercised...

Forgive the repeat but I can't resist this one. Plus it contains a valuable public service announcement...

Until we know more about TSE's it would seem wise to hold off on all those wild animal brain based delicacies. It seems likely that many organisms may have such TSE's but if the species lifespan is only a few years it may be much shorter than the time it takes the prion protein to multiply up to the level that causes symptoms.

Following the observation of an unusual cluster of Creutzfeldt-Jakob cases in Kentucky, the suggestion was made that these may have arisen due to the consumption of squirrel brains - apparently a regional delicacy.

These observations, together with recent concerns about the transmission of a unique encephalopathy in man believed to be related to bovine spongiform encephalopathy led us to examine the possible association of eating squirrel brains with CJD in rural Kentucky, where eating squirrel and other small game is not uncommon. Culinary preparations include scrambling the brains with eggs or putting them in a meat and vegetable stew referred to as “burgoo”.

Normally I dislike the very dry style of scientific writing but this paper, Creutzfeldt-Jakob Disease and eating squirrel brains, contains the following gem:
'(C)aution might be exercised in the ingestion of this arboreal rodent.'

Following Mike Huckabee's revelation that he ate squirrel (cooked in a popcorn popper!) in college Slate investigated.

Tuesday, February 15, 2011

Detecting Mad Cow Disease in Human Blood


According to a paper published in the journal "The Lancet", researchers have found a way to detect the proteins that cause mad cow disease in human blood. As we learned in lecture Mad Cow Disease is contracted by eating beef from infected cattle. It has killed 171 people and resulted in the death of more than 4 million cattle, in order to try to get rid of the disease. It is officially known as Creutzfeldt-Jakob disease. The infection is caused by prion proteins that cause the brain to break down. Since there is not a test to detect the disease it can be passed through blood transfusions.

But recently British researchers have invented a screening test that is able to detect the abnormal prion protein associated with Mad Cow Disease. The tests were run on 190 samples and it was able to detect 15 out of 21 samples from people that have the disease. In addition to the 71.4% success rate the test did not prove any false positives (it didn't incorrectly indicate that the abnormal prion was in any of the healthy samples).

While it would be great to get this screening test used as soon as possible it isn't that easy. It is still unclear whether or not these tests can detect the disease in people who are still in the early stages of the diseases and who do not show symptoms yet.

http://www.latimes.com/health/boostershots/la-heb-mad-cow-20110202,0,1943157.story

2012 budget

President Obama's 2012 budget proposal seems to have something to upset just about everyone:
Left is livid over budget safety net cuts
GOP disses Obama's 2012 budget

However most health related agencies actually did rather well, and those concerned with disease actually see some budget increases. For example:

$11.2 billion for the Centers for Disease Control and Prevention (CDC), up from its FY 2010 budget of $10.8 billion. However, the agency's discretionary spending budget would be reduced from $6.5 billion to $5.9 billion, which is expected to affect occupational safety and health, environmental health and disaster planning program in states. Programs that would see a funding boost include childhood vaccinations, domestic HIV/AIDS programs, and initiatives designed to treat and prevent chronic diseases.

$32.3 billion for the National Institute of Health (NIH), up from $31.3 billion in FY 2011, with a goal of spurring biomedical research and innovation,

$2.7 billion for the Food and Drug Administration (FDA), an increase of about $1 billion from the agency's current fiscal year budget, to enhance its new oversight of food safety and the nation's medicine, medical equipment and blood supplies.

$4.9 billion, an increase of $100 million, for the National Institute of Allergy and Infectious Diseases, which helps fund most of the research into HIV and AIDS nationwide

$5.2 billion for the National Cancer Institute, an increase of $95 million;

$7.77 billion to The National Science Foundation, about 13% above FY 2010 spending, which was approximately $6.9 billion.

prion-like cause for Lou Gehrig's disease?


From the blog Not Exactly Rocket Science:

Imagine a villain that corrupts those it touches. It can convert other individuals into twisted doppelgangers that eventually gather to form a destructive legion. This sounds like a character from any one of a hundred comic books, horror movies or science-fiction shows. But this antagonist is real, and it affects the brains of tens of thousands of people every year. It’s a mutant version of a protein called SOD1, and it causes amyotrophic lateral sclerosis (ALS), better known as Lou Gehrig’s disease.

All proteins are long chains of amino acids that fold up in acts of molecular origami. This has to happen with great precision – if the protein ends up with the wrong shape, it won’t work properly. Some people have mutant versions of SOD1 that sometimes fold incorrectly. These deformed proteins have a habit of clumping together and – in mice at least – the symptoms of ALS get worse as the clumps get bigger. These misshapen versions of SOD1 probably cause around one or two in every hundred ALS cases.

-------------------

Sounds like a prion, right? But it isn't. Prions are defined as being infectious to other people, and extremely hardy and difficult to kill. On the other hand, these SOD-1 proteins do not seem to survive well outside the cell, and do not appear to kill their "host" cells. This may ultimately lead to a treatment that targets the mutant proteins as they spread in the spaces between cells.

But wait, there's more...

ALS and prion diseases are just some of the many brain diseases that are caused by misshapen proteins that gather together in clumps. These doppelgangers are also implicated in Parkinson’s disease, Alzheimer’s disease, Huntington’s disease and more. Bertolotti says that her study is the first to conclusively show that a protein other than prions can “infect” normal proteins with their twisted shapes.

The original journal article can be found here: PNAS article

The blog post is here: Not Exactly Rocket Science

Monday, February 14, 2011

The end of Kuru

A Fore woman in mourning covered with ashes, in 1957.

With the end of cannibalism in New Guinea Kuru gradually declined. In 2006 and 2007 for example there were zero cases and in 2008 the Royal Society of London held a conference to celebrate the end of Kuru. The papers are all gathered together in an issue of the Philosophical Transactions of the Royal Society and, in contrast to most conferences, include a fascinating array of personal recollections as well as scientific papers. These personal recollections are often quite moving. Check out:

‘My late husband Mr Anua was a hard-working man’
'We had to climb mountains and cross fast-flowing rivers'

‘Most people still believe that kuru is caused by sorcery’

There are also more detailed papers about the epidemiology of Kuru:

Understanding kuru: the contribution of anthropology and medicine
Early perceptions of an epidemic

The Fore and a Treatment for Mad Cow Disease

Although the cannibalistic practices of the Fore tribe were banned in the 1950s (presumably as a precaution against kuru), the native people had developed a mutation which protected against the disease. Scientists discovered G127V, a mutation which prevents misfolded prions from attaching themselves to other healthy prions, and therefore preventing the spread of the disease throughout the brain. This is an exciting discovery, because researchers and scientists can work with this mutation to possibly develop a treatment or cure for the disease. Scientists can discern the point where the bad prions attach to the good ones, and therefore can figure out what area of the brain and at what stage they need to target for treatment development.

http://www.telegraph.co.uk/news/worldnews/australiaandthepacific/papuanewguinea/6603676/Brain-eating-tribe-could-help-find-treatment-for-mad-cow-disease.html

Spreading the "Love"


The following is a Valentines message from the National Residence Hall Honorary:

"For the whole week of Valentines, NRHH will be spreading the love around the residence halls! See us tabling? Pick up some free stuff! We will also be having a donation jar, we are raising money to buy teddy bears to give to children in local hospitals, Please donate if you can!"





Sunday, February 13, 2011

Good microbes

We tend to focus on the bad microbes in this class. But let us not forget all those wonderful microbes that make food and drink more interesting. If you like your cheese blue then you owe another debt to the ever versatile Penicillium genus. A number of species in this genus are used to give the characteristic mold veins to Roquefort, Danish Blue, Gorgonzola and the characteristic white rind to Camembert and Brie.

Oscillator, a synthetic biology blog, had a recent post featuring scanning electron micrographs of foodstuffs. I hadn't realized that the Penicillium genus is named after the latin word for "paintbrush" because of its shape.

A Closer Look at Biosafety Level Four

Since labs operating at biosafety level four are used to research the most deadly, incurable, and airborne pathogens, they must make use of the best technology to keep these pathogens locked up. Some of the systems in use to keep pathogens such as the Marburg Virus, and Ebola contained are as follows:

Pressure-Lock Doors: Two sets of stainless steel doors, surrounded with rubber bladders that expand to create an air lock. Often accompanied by a pressure change system which ensures that air can only flow from lower containment to higher containment areas, so it can ultimately be cleaned.

Decontamination Shower: The decontamination shower bombards scientists with water and virus killing chemicals for several minutes before allowing them to move from one area to another.

Clean Air systems: Various systems of ducts and air filters ensure that 99% of all particles larger in size than .0000003 meters in width. This is essential because many pathogens at level four are airborne.

Clean water systems: 1500 gallon tanks collect water that has been used and clean it both chemically and thermally, water is heated to over 250 degrees to kill pathogens.

Nonporous walls: All surfaces the a BSL-4 lab should be completely smooth and have no small spaces for particles to collect. It is common for surfaces to be coated with epoxy to ensure a smooth, easily cleaned surface, and even fire sprinklers are equipped with valves to prevent the travel of particles through the pipes.

Other precautions obviously include protective suits for the workers (including air tanks), very limited access into the lab, and very advanced containments cells for viruses themselves.

These labs are exceedingly expensive to produce, and they are the only situations in which such dangerous disease can be studied. Hopefully labs like this will lead to the cure of today's most dangerous diseases.

Saturday, February 12, 2011

The Andromeda Strain

 I mentioned that Biosafety level 4 was about the most stringent precautions we could take and still allow work on a pathogenic microbe.

The movie 'The Andromeda Strain' closely based on Michael Crichton's book of the same name poses an intriguing question - what precautions would we need to take if we were faced with an almost unimaginable pathogenic threat - a disease from space that appears lethal and highly contagious?

Although this movie naturally appears a little dated now (movie from 1971, book from 1969) the questions asked actually hold up pretty well today. During the era of space exploration in the 1960's and 1970's did the US ever have an equivalent of 'Project Wildfire'?

I actually think this is one of the better disease movies out there.

Friday, February 11, 2011

Not Another Outbreak Movie


Wanting to go along with the lecture today about biosafety and lab outbreaks I found this gem of a movie, Warning Sign, which is of the sci-fi horror genre and is garnered around a "secret" government laboratory, disguised as a pesticide manufacturer (pretty original) in order to pursue work on an extremely virulent biological weapon (not so original).
As you probably assumed, the plot revolves around the fact that a sample is released into the lab and the plant is shut down with the workers quarantined inside, "left to wait out the deadly effects."
Now here it gets interesting: "A local County Sheriff whose pregnant worker wife is trapped inside, and with the help of a past employee who is a known alcoholic, must fight through a government agency and the chemically affected workers to find his wife and put a stop to the spread of the lethal weapon." There are so many things wrong with that. Why is a pregnant woman working in a lab with life-threatening cultures? I'm pretty sure there has to be some kind of regulation that prohibits that. I guess she must find out she's pregnant after the outbreak.
Also let's not forget about the helpful alcoholic buddy who used to work with the pregnant wife in the plant. His past connection with the lab probably stirs him into action when he hears of the outbreak. How noble.
Anyways, the trailer is pretty awesome. My favorite part has to be when some lab attendant slides under some closing barrier for much needed dramatic effect. And if you pause the trailer at exactly 44 seconds you get to see the big nasty disease in action. Apparently it gives you fluorescent green eyes (not a bad symptom) and leaves your skin covered in soap bubbles and black splotches. Unfortunately the trailer does not show how it kills you or how it is transmitted from person to person (even though it is implied that that is the mode of transmission) but it does leave you wanting more. But don't just take my word for it, you can watch the trailer yourself: Warning Sign trailer

The living weapon


The 1972 Biological Weapons Convention prohibited the development, production, stockpiling, and transfer of biological agents for use as weapons. It was ratified by more than 100 nation including the United States. Prior to 1972 however the United States had an active program developing biological weapons.

This program, and the development of biological weapons after the end of World War 2, was the subject of a PBS show in the 'American Experience' series entitled - The Living Weapon, I don't think the full video is on their website anymore but you can read the transcript there and there are a number of other interesting videos and links.

The US originally obtained much of its lead over the Soviet Union in germ warfare by granting immunity from war crimes prosecution to Japanese scientists such as Shiro Ishii who had obtained their knowledge by horrific experiments on living people. Thousands of people died in Japanese facilities such as the infamous Unit 731 in a Japanese-controlled region of China.

At Unit 731, Ishii made his mission crystal clear. "A doctor's God-given mission is to block and treat disease," he told his staff, "but the work on which we are now to embark is the complete opposite of those principles."
Why is there such stigma attached to HIV/AIDS?
  • Strong reactions because it is a life threatening disease.
  • HIV infection is assumed to be the result of personal irresponsibility.
  • Can be infected sexually which often has moral connotations.
  • There are a lot of misconceptions about the disease leading to irrational behavior and confusion over who is at risk.
  • It is often associated with already stigmatized subsets of the population (homosexuals, drug users, etc).
  • Religious beliefs that may lead some people to think that acquisition of the disease is a moral punishment for sins.
The Repercussions of this stigmatization:
  • Loss of income/livelihood
  • Loss of reputation/ pride in oneself
  • Loss of hope & feelings of worthlessness in infected individuals.
  • Withdrawal of caregiving in the home.
  • Poor or unequal acccess to proper health care.
  • Dissolution of marriage/ problems bearing children

www.avert.org/hiv-aids-stigma/

Thursday, February 10, 2011

Private Rooms in Hospital Intensive Care Units Could Be a Life Saver

While private rooms are extremely nice for patients and families this new study has shown that they are safer too. As we learned in lecture many ICU patients wind up with some kind of infection during their stay at the hospital [nosocomial acquired infection]. These infections keep people in the hospital for an additional eight to nine days which adds an estimated $3.5 billion to the nation's healthcare tab each year. While this may seem like an impossible sum to reduce there is a simple solution: make all the ICU rooms private.

At Montreal General Hospital, the infection rate considerably fell after a new ICU was opened. This unit only contained single-occupancy rooms. Between 2000-2005, the rate that ICU patients acquired MRSA, Clostridium difficle, VRE was 54% lower than in the ICU at the nearby Royal Victoria Hospital. At the Royal Victoria Hospital there were only 8 rooms that were private with a majority of them share up to six beds.

When the study looked only at MRSA rates alone, the infection rate was 47% lower at Montreal General than Royal Victoria. For C. difficle the rate 43% lower. There was also a difference in the amount of time patients spent at the hospital. Just like the simple solution of Doctor's washing their hands, this easy solution could achieve great results.

Teaching hospital medical staff to handwash

Someone asked for the reference for the Australian handwashing study. The papers is called  Teaching hospital medical staff to handwash, and is from the Medical Journal of Australia in 1996.

The study contains several more elements than I mentioned in class including an initial covert observation (the low rates of ~10% I mentioned), an estimate by medical personnel of their compliance rate (the 73% figure I mentioned), a period of overt observation and finally a period of overt observation and performance feedback.

In this case handwashing rates covertly observed 7 weeks after the end of the study were ~50%, a huge improvement on the initial values of ~10%. The authors drew the conclusion that 'Performance feedback is moderately effective in training hospital medical staff to handwash'. I guess 50% is better than 10% but it takes the offer of a free cup of coffee to get it higher...

"Ebola is Beautiful"




Scientist Hunter Cole is a member of the new bioartist movement who creates works of art using scientific imagery, such as photographs of the ebola virus, seen here in her work "Ebola is Beautiful". Her other notable works include photos of mice embryos and another work entitled "Anthrax Clock," in which a woman is shown dying from anthrax poisoning in the span of 12 hours.

Hunter Cole's website here

Wednesday, February 9, 2011

Nosocomial Infections and Bath Basins

Apparently there's another way, besides through unwashed hands and infected teddy bears, to contract a nosocomial infection: wash basins. According to Justine O'Flynn, a RN who conducted research on this topic at her hospital in Kentucky, wash basin pose a threat to patients for a number of reasons. First of all, the water can easily become contaminated through unwashed hands or through reusable wash cloths. The cloths and hands can transport bacteria into the water, which subsequently infects the patient, often entering the body through cuts, scrapes, or sores. Bacteria can also be spread from person to person through contaminated water.
In addition, O'Flynn testifies that half of the wash basins that were tested in her hospital showed signs of organism growth. Although this statistic is from one hospital, I would assume that many other hospitals in the country would have a similar statistic.
To combat the potential infection threats, O'Flynn suggests that hospitals start to use packaged cloths with cleaning agents already in them instead of wash basins. This would decrease the risk of infection because there would not be as many chances for patient to patient or doctor to patient contamination.

http://http://www.infectioncontroltoday.com/articles/2007/11/bath-basins-as-a-source-of-hospital-associated-in.aspx

Experimental Vaccine Used on Human

An experimentla vaccine for Ebola virus was used on a doctor who pricked her finger with a needle that they were using to inject Ebola into lab rats. Her potential exposure and the incredibly deadly nature of this disease led to drastic action being taken. As this video will explain further, the scientist was given a vaccine never before used on humans. She was isolated from the start, and it was never known if she was actually infected. According to Wikipedia, she passed the 21 day incubation period with no outbreak or signs of the virus, so she has been declared healthy and safe. They are unable to determine if the vaccine saved her (it was her final decision on whether or not to accept the treatment) or if she was simply never infected, but at least this demonstrated that the vaccine seems to have no short term effects on humans (of course, this is with a sample size of one). Very interesting, and it also details just how seriously Ebola exposure is taken, as she was quarantined from the beginning of the entire ordeal and the scientist remains unnamed according to the video

Contagion (film)


The newest disease related film about is certain to get alot of attention. Contagion, directed by Steven Soderbergh (Traffic, Ocean's Eleven), is about a team of international doctors (and not just any international doctors, but incredibly good looking ones) contracted by the CDC to deal with an outbreak of a deadly disease. With its all-star cast including Matt Damon, Kate Winslet, Jude Law, and Gwyneth Paltrow, this one looks destined to be a blockbuster hit. Insiders who have gotten a look at the script say that clearly alot of research went into this, and that the film ties the storyline of global pandemic into how information spreads in the Internet age. To me, it sounds like it could not only be a tense thriller about disease but also about how media and misinformation lead to mass hysteria (Y2K meets swine flu), and how this may affect global events in the future. The best part about ambitious film, is that the writer has the virus surface on BLACK FRIDAY, quite possibly the worst time a deadly virus could show itself in America. Keep your eyes out for this one.