Malaria in the US

A fascinating map of malaria in the USA in 1870 from the Library of Congress digital history collection (click here for a zoomable version).

Even though malaria was never a massive problem in the US as a whole it was certainly a problem in parts of the South as this map indicates. The darkest red color indicates a malaria mortality of over 1,400 per 10,000 - ie 1 in 7 people were dying of malaria.

In the US Civil War, where much of the action took place in these malarious states, large numbers of soldiers contracted Malaria and tens of thousands were killed.

The most shocking fact is that in 1870 no-one yet realized that mosquitoes were transmitting the disease.

Here's an excerpt from a Scientific American article entitled The Civil War and Malaria.

THE SCIENTIFIC AMERICAN’S ADVICE TO OUR SOLDIERS--MALARIA AND ITS REMEDIES
It is difficult for us to realize the fact, but we all know that any soldier is in five times more danger of dying from malarious disease than of being killed in battle.
WHERE MALARIA EXISTS
What malaria is nobody knows. It may consist of organisms, either animal or vegetable, too minute for even the microscope to detect or it may be some condition of the atmosphere in relation to electricity, or temperature, or moisture; or it may be a gas evolved in the decay of vegetable matter. The last is the most common hypothesis, but it is by no means proved, and it has some stubborn facts against it. There is no doubt, however, that malaria is some mysterious poison in the atmosphere, and that it is confined strictly to certain localities.

Global Malaria burden

Here's an article from the Guardian newspaper about some recent revisions to the number of people estimated to die from malaria each year.

Malaria deaths country by country: how many are there?
What we thought we knew about Malaria deaths is wrong: the reality is much, much worse. See what the new detailed data says.
Whilst the good news is that the current estamted total number of deaths is still down from a high of nearly 2 million people per year, the bad news is that it nearly doubles some other estimated figures. The discrepancy largely comes about from a difference in adult deaths.

Malaria proof mosquitoes

A 'malaria proof' mosquito' would be an valuable tool in the fight against malaria. It looks like scientists have created just such a mosquito - through a combination of disrupting the parasite development and reducing the mosquitoes lifesapn (as we discussed in class). Now all we need is a way to give such mosquitoes a competitive edge so that they replace the
 native mosquitoes...

Activation of Akt Signaling Reduces the Prevalence and Intensity of Malaria Parasite Infection and Lifespan in Anopheles stephensi Mosquitoes. PLoS Pathogens, 2010;

It was known that the Akt enzyme is involved in the mosquito's growth rate and immune response, among other things," Riehle said. "So we went ahead with this genetic construct to see if we can ramp up Akt function and help the insects' immune system fight off the malaria parasite."
The second rationale behind this approach was to use Akt signaling to stunt the mosquitoes' growth and cut down on its lifespan.
"In the wild, a mosquito lives for an average of two weeks," Riehle explained. "Only the oldest mosquitoes are able to transmit the parasite. If we can reduce the lifespan of the mosquitoes, we can reduce the number of infections."

Rinderpest @ number 2

The eradication of smallpox (certified by the WHO in 1979) led to a period of optimism that other diseases would be soon vanquished. I don't think anyone expected that it would be over three decades before another disease fell - Rinderpest declared extinct by the WHO in 2011.

A number of newspapers had nice articles describing both the historical importance of Rinderpest and also the eradication program.

The New York Times made the point that with the disease is relatively unknown in America because with the exception of a brief, contained outbreak in Brazil in 1920, it never reached the Americas. (Rinderpest, Scourge of Cattle, Is Vanquished.)

The Washington Post explains that three things made rinderpest eradicable. Animals that survived infection became immune for life. A vaccine developed in the 1960s by Walter Plowright, an English scientist who died last year at 86, provided equally good immunity. And even though the virus could infect wild animals, it did not have a reservoir of host animals capable of carrying it for prolonged periods without becoming ill. (Rinderpest, or ‘cattle plague,’ becomes only second disease to be eradicated.)

Swimming in sick seas

There was a session on ocean health at last month's Annual Meeting of the American Association for the Advancement of Science (AAAS) in Vancouver, Canada.


A number of news outlets picked up on the news that pathogens of terrestrial animals are killing ocean mammals: Iconic Marine Mammals Are 'Swimming in Sick Seas' of Terrestrial Pathogens

Parasites and pathogens infecting humans, pets and farm animals are increasingly being detected in marine mammals such as sea otters, porpoises, harbour seals and killer whales along the Pacific coast of the U.S. and Canada, and better surveillance is required to monitor public health implications, according to a panel of scientific experts from Canada and the United States.

Between 1998 and 2010, nearly 5,000 marine mammal carcasses were recovered and necropsied along the British Columbia and Pacific Northwest region of the U.S., including whales, dolphins and porpoises, sea lions and otters.

"Infectious diseases accounted for up to 40 per cent of mortalities of these marine animals," says Stephen Raverty, a veterinary pathologist with the Animal Health Centre in the British Columbia Ministry of Agriculture and Lands, and an adjunct professor in UBC's Marine Mammal Research Unit.

"In many cases, the diseases found in these marine mammals have similar or genetically identical agents as those infecting pets and livestock. We don't yet know how these diseases are affecting the health of marine mammals" says Raverty.

After the Rinderpest

Bill Knight 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.

You can download a free 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.

Sperm bank shortage

One of the oddest consequences of the United Kingdom's BSE epidemic of the 1990's has been the United States ban on sperm from Scandinavia.

In September 2003 the Food and Drug Administration banned the import of donor sperm from 30 countries, where Mad Cow disease has been detected in cattle - despite the fact that most scientists believe it is virtually impossible for vCJD to be spread through sperm.

Up until this point Scandinavian sperm had, apparently, been the most popular choice for US sperm bank customers who frequently seek blond haired blue eyed babies. Although the ban was enacted in 2003 it didn't really attract much attention until 2007 and 2008 when sperm banks ran out of their stocks of Scandinavian sperm.