Thursday, March 10, 2011

Culling Chickens as a Result of Avian Influenza Outbreak in India


After an outbreak of Avian Influenza in India veterinatires. In Tripura in a state-owned poultry farm in Ganhigram, veterinarians started to cull their chickens. This farm is one of the main breeding centers and it has a capacity of around 7,000 chickens.

Samples were sent to the High Security Animal Disease Laboratory in Bhopal after 380 birds died between March 1 and March 4. The samples tested for HIN5.

The culling is going to continue for the next few days in order. They people in charge of the poultry farm announced that they still have 1,400 Japanese peahens and 20,000 eggs that have to be dumped. Also the poultry in the surrounding 10 Km would be culled as well.

This is not the first time this outbreak has occurred in India. The last time there was an outbreak was in 2006.

http://www.medindia.net/news/Tripura-Starts-Culling-of-Chickens-After-Bird-Flu-Outbreak-81927-1.htm

Thermal scanning for flu

If there is an influenza pandemic then initial attempts at isolating the outbreak, or prevent its entry into particular countries, may involve the use of infrared thermal image scanners (ITIS) at airports to detect people with elevated body temperatures characteristic of influenza. We saw this in the 2009 H1N1 (Swine Flu) pandemic. Analysis suggests that countries that adopted the policy managed to delay disease entry for 7-12 days compared to countries that did not: Entry screening to delay local transmission of 2009 pandemic influenza A (H1N1). Of course there may be other differences between these two types of countries. Correlation is not causation...

A paper in PLoS ONE in January this year, Thermal Image Scanning for Influenza Border Screening: Results of an Airport Screening Study, looked at a sample of 1275 airline passengers who agreed to be screened, have their temperature actually measured and give a respiratory sample. Six of the travellers had a fever and thirty of the travellers tested positive for influenza. But none of the influenza-positive travellers had a temperature high enough to be considered in the fever group!

Our findings therefore suggest that ITIS is unlikely to be effective for entry screening of travellers to detect influenza infection with the intention of preventing entry of the virus into a country.

I'm sure we'll see more of these thermal scanners in airports in future pandemics even if they are fairly useless. Why? Because it makes it look like somebody is doing something (even if it is useless). Just like the rest of airport security

"Junk" Medicine


As the government releases 600,000 doses of the H1N1 vaccine today, predatory online “pharmacies” are dispensing junk medicine to a frightened public.

With the first 600,000 doses of swine flu vaccine scheduled to be released today and the media already swirling about how difficult it will be to get a dose, scam artists from Internet “pharmacies” are lining up to bridge the gap.

Specifically, the U.S. Food & Drug Administration, the World Health Organization and the pharmaceutical industry are bracing for an onslaught of fake and substandard drugs, with a special eye out for unauthorized versions of Tamiflu, the patented Roche vaccine that is the cornerstone of the public health-effort. “We don’t know what we could be seeing in the next few weeks,” says Gary Coody, who coordinates health-care enforcement for the FDA. “They (Internet drug operators) don’t necessarily have any regard for public-health safeguards.”

full blog post: "Swine Flu Swindle"
http://www.thedailybeast.com/blogs-and-stories/2009-10-05/swine-flu-swindle/

Wednesday, March 9, 2011

Blog wind up

A big hand for this quarter's bloggers: Ethan, Emily, Meghan, Blair, Nate, Kelsey, Marise and Eric. I hope you all enjoyed reading the blog, it really works well when we get several people involved and there are several new posts each day (as opposed to me scrambling to post something before midnight each day). I think we broke records this quarter for the overall number of posts and also the most posts in one day.

I'll keep posting until Friday and then I'll wrap up with some review questions etc.

New H1N1 Mutation





An article published in Science Daily today reveals that a mutation in the H1N1 strain of influenza virus (aka "swine flu") may allow it to become more easily transmitted from person to person. The strain of flu that the WHO declared a pandemic back in 2009 is actually a mixture of human, bird, and pig influenza genes. Despite the enormous amount of media attention it got, it proved to not be significantly deadlier or more debilitating than the seasonal flu humans encounter nearly every year. The swine flu proved to be relatively inefficient at moving from person to person... until now. Researchers at MIT have discovered a mutation that may allow this flu virus to transmit much more rapidly and effectively from person to person. A potentially deadly mutation to the virus' hemagglutin has been identified, but this should allow to WHO to quickly identify any outbreaks of the potential new strain and determine how deadly it can be. MIT scientists merely altered 1 amino acid chain that allowed the Hemagglutin to bind much more strongly to respiratory cells, increasing its ability to infect as well as kill humans. They identified this mutation as being a very possible one for the swine flu to evolve into. As the article is quick to point out (namely, the first few sentences), this potential two-wave pattern of flu outbreak is similar to the infamous 1918 Spanish Flu, which killed around 50 million people. Keep your fingers crossed everyone.

Tuesday, March 8, 2011

Swine Flu Survivors Built Super Flu Antibodies

A study of antibodies in people who were infected with H1N1 swine flu suggests that a universal flu shot that could neutralize many flu strains, including swine and avian flu. Scientists believe that people who were infected with H1N1 developed a unique immune response in which antibodies that could protect them from all the seasonal H1N1 flu strains that have appeared in the last decade were produced. A universal flu vaccine could have a major impact in controlling influenza which kills anywhere from 3,300 to 49,000 people every year in the U.S. Scientists are currently working on a vaccine from antibodies isolated from nine people who were infected with the first wave of the H1N1 swine flu pandemic. Of these, five of the antibodies were cross-productive so that they are able to interfere with many different flu strains. Studies in mice show that they were protected from what is considered a lethal dose of the flu. The vaccine is currently being tested in people.

Polio: To eradicate, or not to eradicate

Polio is one of the few human diseases that is on the brink of eradication. This article in the New York Times discusses the debate between Bill Gates, who has donated $1.3 billion for polio eradication, and public health experts who believe that polio eradication is not worth the cost. Gates points out that we have an effective and inexpensive vaccine, and that polio has been scaled back to just a few countries. Here's what some other experts say:


“Bill Gates’s obsession with polio is distorting priorities in other critical BMGF areas. Global health does not depend on polio eradication.” (The initials are for the Bill & Melinda Gates Foundation.) -- Richard Horton, editor of The Lancet

“We ought to admit that the best we can achieve is control.” -- Arthur L. Caplan, director of the University of Pennsylvania’s bioethics center, who himself spent nine months in a hospital with polio as a child.

Gates counters: “These cynics should do a real paper that says how many kids they’re really talking about. If you don’t keep up the pressure on polio, you’re accepting 100,000 to 200,000 crippled or dead children a year.”

Right now, there are fewer than 2,000. The skeptics acknowledge that they are arguing for accepting more paralysis and death as the price of shifting that $1 billion to vaccines and other measures that prevent millions of deaths from pneumonia, diarrhea, measles, meningitis, and malaria.

“And think of all the money that would be saved,” Mr. Gates went on, turning sarcastic. “It’d be like 5 percent of the dog food market in the United States.” (Americans spend about $18 billion a year on pet food, according to the American Pet Products Association.)

“If we fail, we’ll be consigned to continuing expensive control measures for the indefinite future,” said Dr. Thomas R. Frieden, director of the Centers for Disease Control and Prevention, which leads the country’s effort.

The article also points out some of the differences between polio and smallpox that have made polio so much harder to eradicate.

One injection stops smallpox, but in countries with open sewers, children need polio drops up to 10 times. Only one victim in every 200 shows symptoms, so when there are 500 paralysis cases, as in the recent Congo Republic outbreak, there are 100,000 more silent carriers. Other causes of paralysis, from food poisoning to Epstein-Barr virus, complicate surveillance. Also, in roughly one of every two million vaccinations, the live vaccine strain can mutate and paralyze the child getting it. And many poor families whose children are dying of other diseases are fed up with polio drives.

Not an easy debate to choose a side in, at least for me...

Flightless mosquitoes may curb dengue


Genetically altered mosquitoes that cannot fly may help slow the spread of dengue fever and could be a harmless alternative to chemical insecticides, U.S. and British scientists said on Monday. [Feb 22, 2010]

They genetically altered mosquitoes to produce flightless females, and said spreading these defective mosquitoes could suppress native, disease-spreading mosquitoes within six to nine months.

There is no vaccine or treatment for dengue fever, which is endemic in the tropics and is particularly prevalent in Asia and the western Pacific. The disease, which causes severe flu-like symptoms and can kill, is spread through the bite of infected female Aedes aegypti mosquitoes.

"This could be the first in a new wave of products that might supplant insecticides," researcher Anthony James of the University of California, Irvine, said in a telephone interview.

James's team, including a group from the British biotechnology firm Oxitec Ltd., altered mosquito genes to disrupt development of the insects' wing muscle.

The genetic modification grounded only the virus-carrying females and did not affect the males' ability to fly, they wrote in the Proceedings of the National Academy of Sciences here

The idea would be to distribute tens of thousands of eggs that would hatch out these genetically modified males, that would proceed to create a new generation of flightless, and thus doomed, daughters.

Because eggs are so small and easy to distribute, there would be far more genetically modified mosquitoes than natives, so they could in effect blot out the dengue-carrying population.

http://www.reuters.com/article/2010/02/22/us-mosquitoes-dengue-idUSTRE61L5JI20100222

Flu trends


Google has been tracking flu trends for some time by analyzing people's choice of search terms. This method has been very successful and they can usually pick up trends a few weeks before the CDC data. In 2009 a variety of workers from Google and one from the CDC published a paper in Nature describing their technique: Detecting influenza epidemics using search engine query data.

For epidemiologists, this is an exciting development, because early detection of a disease outbreak can reduce the number of people affected. If a new strain of influenza virus emerges under certain conditions, a pandemic could ensue with the potential to cause millions of deaths (as happened, for example, in 1918). Our up-to-date influenza estimates may enable public health officials and health professionals to better respond to seasonal epidemics and pandemics. 
 
The graph above shows, for the United States as a whole, that the peak flu season is usually in February and that we are probably past the peak this year. You can also see how unusual last year was, pandemic years are always different. The big peak in October is from 2009-2010. The same pattern was seen in California except that our peak flu season seems a bit less predictable.

Monday, March 7, 2011

PNAS

Two relevant but rather different papers in the latest Proceedings of the National Academy of Sciences (PNAS).

In the first: Bacillus anthracis comparative genome analysis in support of the Amerithrax investigation, they describe how genomic analysis was used in the investigation of the 2001 anthrax attacks.

The paper describes how the Institute for Genome Sciences faculty and collaborators from the FBI found that the anthrax samples used in all the attacks were genetically identical. Later, another group of scientists -- also including Institute for Genome Sciences faculty -- would trace the anthrax spore used in the letters back to a flask of Bacillus anthracis and several samples taken from that flask. The primary custodian of the flask was Bruce Ivins, Ph.D., a scientist at a U.S. Army biodefense laboratory in Maryland. With this key investigative lead from the scientific team, the FBI used additional police work to conclude that Dr. Ivins was the perpetrator of the mail attacks. Dr. Ivins killed himself before the case could go to court. The FBI has since closed the Amerithrax investigation. (From a report at ScienceDaily)

In the second paper, Hybrid influenza viruses may have pandemic potential, which is relevant to this weeks discussion,  the authors describe how the H1N1 strain that caused the 2009 pandemic, but relatively few deaths, may yet turn out to be problematic. 

The H1N1 influenza virus that spawned the 2009 pandemic is now predicted to circulate as a seasonal flu. However, researchers fear it could once again present a major public health threat by recombining with the H9N2 virus, which is endemic to several bird species in Asia, and has infected pigs and humans. Yipeng Sun et al. explored this possibility by dissecting the H1N1/2009 and H9N2 influenza viruses, and systematically mixing their genes to generate 127 hybrid viruses. The authors then tested the hybrid viruses in mice to assess the likelihood that genetic reassortment between H1N1/2009 and H9N2 could create a virus of pandemic proportions. More than half of the hybrid viruses instantly infected mice and replicated as efficiently as did the parent strains. Eight of the hybrids proved more virulent and dangerous than did either of the two parent strains. Curiously, each of these eight strains carried a gene encoding part of the RNA polymerase, known as the PA gene, from the pandemic H1N1/2009 virus. The authors suggest that the pandemic PA gene may play a key role in the virus’s pathogenicity, and that screening H9 viruses for the gene might help identify influenza viruses that pose a public health risk.

Building Immunity- Research for Artificial Antibodies

As you should know, antibodies are the bodies agents for seeking out pathogens, clumping them together, and signaling to the body so they can be destroyed by the immune system. Currently, the favored technique for getting new antibodies is to introduce the pathogen to an animal, and then to remove the antibody (or what created them) for further use.

Researchers at Arizona State University are pioneering a new method in which random chains of amino acids are combined to produce the artificial antibodies. The wondrous thing about this new method is that even when combined at random, the amino acids come together to produce something that can bind to a few proteins. After created, the "antibodies" are checked for matches with many, many proteins so scientists can find out what they might be the antibody to.

The advantages of this method are related mainly to saving time and money. This method is much easier (and humane) than waiting for a disease-infected monkey to create antibodies, and then stealing away the monkey's hard earned defenses through a needle, and it saves costs such as Mr. Banana's food and board. Obviously this method can't be used to easily create an antibody to anything that scientists want to fight, but with its low cost and easiness, this method should allow many new antibodies to be found.

Mosquito Nets Used for Fishing


When we covered Malaria in class, we discussed the helpfulness of Insecticide Treated Nets and learned about non-profit organizations focused on ending Malaria, which raise money to send these nets to infected countries. However, one student shared that he visited one of these countries and learned that the nets are actually stolen by fishermen and are not reaching the people who need them most. After doing some research, I found that the student was absolutely right: these nets are being used for fishing because they are stronger than normal nets and do not disintegrate. This is especially prevalent in Kenya and Zambia, but is a problem in many other countries as well. According to malariaworld.org, "This phenomena has caused an increase in the malaria prevalence rate along the coastlines of various African countries."

Sunday, March 6, 2011

More iron lungs

When people are nostalgic for the 'simpler' times of the 1950's (after the war but before the turbulence of the sixties) they usually conveniently forget about horrors such as polio and iron lungs. These days many people probably only think of an iron lung as a Radiohead song, and even then many people miss the metaphor - something that keeps you alive but becomes very restrictive.

I am amazed by people who have lived their whole lives in them but have remained cheerful and happy. As well as the story below about John Prestwich there is also the story of Martha Mason who has lived in an ironlung for over 60 years.

(A)s one of the few surviving people left who live their lives encased in an iron tank, she said she intends to continue as she always has -- making the most out of what life has offered her.
"Get as much joy from life for yourself and others as you can squeeze out of it," she said.

Saturday, March 5, 2011

Polio: a virus' struggle

The story of Polio in comic book form. by James Weldon, a journalism student at the University of British Columbia. Learn the full story from the polio virus itself as it tells all in a group therapy session for 'diseases nearing extinction' with smallpox, guinea worm and leprosy. Lots of little jokes in here and a surprising amount of information. Enjoy.

Man lives in iron lung for 48 years

John Prestwich has needed the assistance of an iron lung for 48 years as a result of his teenage polio infection. However, John does not see his iron lung as a sort of prison, but rather embraces it as a life-saving friend. Prestwich would be unable to live without the lung, and if the machine stopped working he could die within three minutes.

However, he does not have to live in the iron lung all the time. With modern technology, people designed a smaller machine that he can use at home. The new machine is the size of his chest and performs almost the same exact functions as the large iron lung.

Prestwich also shares parts of his personal story:

http://news.bbc.co.uk/2/hi/health/3182096.stm

Friday, March 4, 2011

Guinea Worm

The reason I wanted to briefly mention Guinea Worm at the end of today's lecture is that it looks like it will be a close race with Polio as to which disease is eliminated next. Both diseases are close to the verge of extinction, only found in 4 countries each and both had under 2,000 cases worldwide last year - down from a total that was once in the millions.

However what makes Guinea worm a very interesting case is that the main tool in eradication has not been vaccination (there is no vaccine) but has been breaking the life cycle of the parasites by both encouraging the use of clean drinking water and by preventing people from entering sources of drinking water with an active infection. Since there is no host other than man the disease can be eradicated if there are no infected people,

Guinea worm disease is set to become the second disease in human history, after smallpox, to be eradicated. It will be the first parasitic disease to be eradicated and the first disease to be eradicated without the use of a vaccine or medical treatment.

Much of the work in eradicating Guinea Worm has been funded by former President Jimmy Carter and the Carter Foundation. For over two decades the Carter Foundation have been slowly winning the war against Guinea worm.

Time magazine had a photo-essay on the effect of Guinea Worm on a Ghanaian village.

Thursday, March 3, 2011

Malaria Idol - 2010



In June of 2010, the nonprofit Malaria No More wanted to encourage people to use bed nets in order to prevent malaria. On June 9, 2010 in Dakar, Senegal nine finalists took to the stage to vie for a recording deal. All of the songs sung were written by the contestants and they were all on the topic of prevent malaria. The idea behind the campaign is simple and brilliant: if you’re working in public health and you want to change people’s behavior for the better, don’t try to convince them yourselves. Instead, find someone outside the medical community who already knows how.

The video above was recorded by one of Senegal's biggest pop stars. It is a cautionary tale about protecting yourself from malaria. It was released with a special concert the night before the Senegalese government kicked off a massive distribution of bed nets for all children younger than 5.

http://www.newsweek.com/blogs/the-human-condition/2010/06/09/malaria-idol-in-senegal-using-music-to-send-a-message.html

Are bednets the solution?



Not everyone agrees that bednets should be the main focus of our malaria eradication campaign. This video raises a number of very good points, particularly that the western world eliminated malaria via the use of DDT, a tool we now deny to other countries.

For further reading on the issue of using pesticides such as DDT check out Tina Rosenberg's controversial article in the New York Times: What the world needs now is DDT.

Also, it is interesting to note that even Rachel Carson, whose book Silent Spring sounded the alarm on the environmental dangers of DDT, did not call for a total ban on DDT:

Practical advice should be "Spray as little as you possibly can" rather than "Spray to the limit of your capacity."

Unfortunately because we did the latter we eventually saw environmental consequences and ultimately banned DDT, but only after we had eliminated malaria. Is it right to deny this tool to other countries, even its appropriate use, because we screwed up?

Comedians Fight Malaria


In this new campaign by Malaria No More, comedians including Elizabeth Banks and Aziz Ansari come together to end malaria deaths in Africa by 2015. Listen to the luminaries share their childhood dreams in this PSA.

View the 1 minute campaign clip for a light-hearted yet inspirational step in the cause of putting a stop to malaria.
http://www.youtube.com/watch?v=ybNEsrh2eIE&feature=player_embedded

Then take a look at the Malaria No More webpage--a site promoting the Malaria No More campaign. Malaria is a preventable and treatable disease and recent progress shows that malaria's days are numbered — but our help is needed. Together, we can make malaria no more. As seen in the video clip, Hollywood icons are using their powerful voices to make a difference. As part of the campaign, a large group of them are hosting "Hollywood Bites Back!," a live comedy show on April 16 at Nokia Theatre in L.A. to benefit Malaria No More.
http://www.malarianomore.org/

Wednesday, March 2, 2011

Malaria & Malnutrition

Young children are more likely to fall victim to food shortages and thereby malnutrition, which increases their susceptibility to infectious disease, including an increase in mortality due to malaria. Severely malnourished children with a malarial infection may have no fever and show few or none of the classic signs of the disease, making it much more difficult to diagnosis & treat effectively. The World Health Organization suggests that all malnourished children in regions where malaria is endemic be screened proactively for malaria weekly even when they show no symptoms.

Depressing Polls

At the end of today's class I showed you some poll data on the public's opinion on cutting foreign aid. This result has been fairly consistent across a variety of polls.. For example Gallup repeat some of their polls on a yearly basis and this year's data, which has just been released, is no exception.

(A) majority of Americans said they favor cutting U.S. foreign aid, but more than 6 in 10 opposed cuts to education, Social Security, and Medicare. Smaller majorities objected to cutting programs for the poor, national defense, homeland security, aid to farmers, and funding for the arts and sciences.

One of the explanations for this rather ungenerous attitude is that the US public vastly over estimates how much money the government actually gives in foreign aid. This, again, has been shown by several research polls and seems to be a fairly consistent result. (Interestingly, and perhaps logically, people greatly underestimate how much of the US budget goes to other sources such as Medicare/Medicaid and defence.)

The only good news I can give you is that according to Kaiser Family Foundation 2010 Survey of Americans on the U.S. Role in Global Health when the specific purpose of the foreign aid is explained it is more likely to be supported.

When it comes to U.S. foreign aid in general, six in 10 Americans (61%) say the U.S. spends too much, and four in 10 incorrectly think that foreign aid is one of the two biggest areas of spending in the federal budget.  In comparison, when asked about “improving health in developing countries,” 28 percent say the U.S. spends too much, while nearly two thirds say such spending is too little (23%) or about right (42%).

“The old canard that most Americans do not support ‘foreign aid’ is a misunderstanding of how the public really feels,” said Kaiser President and CEO Drew Altman.  “When the specific purposes of spending abroad are put before the public, Americans are more supportive of health and development funding.”

Tuesday, March 1, 2011

Mechanics of Malaria: Elasticity of Red Blood Cells

The researcher from Brown and MIT are coming closer to finding valuable information that could lead to a cure for malaria, mainly cerebral malaria. The researchers are studying the effects of Plasmodium falciparum, the parasite causing cerebral malaria, on red blood cells. This form of malaria mainly affects children and is one of the deadliest forms of malaria.

The main goal of this research was to examine the features of this disease from a mechanical point of view. Through their research the team has discovered that the red blood cells that are affected by the parasite Plasmodium falicparum were far stiffer and more adhesive than healthy red blood cells. They stretched the cells in order to examine their elastic properties and saw that these infected cells were 10-20 times stiffer than normal cells.

Since red blood cells have to be fast messengers, traveling quickly through the capillaries, these stiffer cells cannot travel at the same speed. Also, since the cells become adhesive they tend to travel closer to the walls of the arteries while healthy red blood cells travel through the center. These two characteristics of the infected blood cells cause these red blood cells to stick to the capillaries in the brain, thus causing them to not reach the spleen. The spleen is responsible for filtering parasites from the blood. These infected red blood cells are unable to transport nutrients and oxygen to the rest of the body.

These discoveries could provide information extremely valuable to treating malaria.

http://www.browndailyherald.com/mechanical-view-sheds-light-on-malaria-1.2459334

Malaria Site: All About Malaria


While searching for something malaria-related to post on the blog this week I stumbled upon this site: Malaria Site. The website has numerous fascinating sections dedicated to the history of malaria including reports on the earliest written descriptions of malaria dating back thousands of years ago to Babylonian cuneiform tablets which attribute the disease to Nergal, the Babylonian god of destruction and pestilence (described as a double-winged, insect).

The site even has a section dedicated to "Famous Victims" which include notable figures such as Italian author Dante, Oliver Cromwell, Lord Byron, and a list of 8 American president's who suffered from the disease (though none of them died).

There is a lot of neat stuff on the website that I would advise you to check out if you're interested: Malaria Site.

Fighting Malaria with Candy


A spoonful of sugar may help the medicine go down, but why bother when you could just give patients chocolate? That's what Bill Gates wants to do.

Through the Bill & Melinda Gates Foundation, he's given $100,000 in grants each to scientists who want to use candy to diagnose and treat malaria. UCLA doctoral candidate Andrew Fung received a grant to use gum to detect malaria indicators in saliva, making the test painless. Steven Maranz, a researcher at Weill Cornell Medical College will use his money to study the effects of chocolate, which binds to and removes the cholesterol the malaria parasite needs to survive from the bloodstream. Maranz thinks chocolate may be able to kill most parasites while leaving enough in the blood to help children develop a lifetime resistance. The five-year grants for malaria are part of the foundation's Grand Challenges Exploration program, which also gave $100,000 to 74 other unconventional approaches to world problems.

from an article dated October 2009

Walter Reed: Physician, Researcher, Soldier

From the Military Health System website at the Department of Defense a short video about Major Walter Reed’s contributions to military medicine, which include discoveries that paved the way for health care modernization at the dawn of the 20th century.