Stanley Prusiner

There's also an interview with Prusiner at the Nobel Prize website.

The rise and fall of kuru

Historical research carried out by Michael Alpers (see below) on the Fore suggests that the epidemic may have originated around 1900 from a single individual who lived on the edge of Fore territory, who is thought to have spontaneously developed Creutzfeldt-Jakob Disease (CJD).

Cannibalism, and possibly other funeral practices then led this single case to become an epidemic.

When cannibalism was outlawed in the 1950's Kuru began to decline although cases continued to appear for several decades more - suggesting a potentially very long incubation period.

The last kuru sufferer died in 2005 and active field surveillance was continued until 2010. It appears that Kuru has died out and the epidemic is finally over.

In recent years scientists have been studying the survivors of the Kuru epidemic and have found that some individuals have a strong genetic resistance to the disease. This could be very valuable in suggesting treatments for other prion diseases.

"Kuru comes from the same disease family as CJD, so the discovery of this powerful resistance factor opens up new areas for research taking us closer to understanding, treating and hopefully preventing of a range of prion diseases."

The Science and the Sorcery

Kuru: The Science and the Sorcery

Australian scientist Michael Alpers dedicated over 50 years to researching Kuru, an obscure and incurable brain disease unique to the Fore people of New Guinea. Kuru was once thought to be a psychosomatic illness, an infection, a genetic disorder, even a sorcerer's curse, but Alpers' findings pointed to cannibalism as the culprit. Yet a recent discovery has proven to be even more disturbing: the malady is linked to mad cow disease and its human equivalent, variant CJD. With a decades-long incubation period, could a larger outbreak be on its way?

Disease Sleuths

I've posted about Google's flu tracker and how Twitter is being used to track diseases before but I thought NPR's little animation was nice. The article: Disease Sleuths Surf for Outbreaks Online expands on it and is also interesting. This type of tracking is not suitable for all diseases:

In the early days of the cholera outbreak, Twitter and HealthMap data closely matched official reports. After 100 days online activity dropped off even though the epidemic raged on. Disease is easiest to detecte when it is out of the ordinary. Regularly recurring maladies like malaria are hard to follow online.

But it's a hot topic at the moment and even has a new name 'Webidemiology'. I hadn't realized that Google had expanded its surveillance to include Dengue Fever.

Suicide rats

I found this video from the Australian Broadcasting Corporation (ABC - nothing to do with the ABC network in America). It looks like Catalyst is a regular science show on the network. This show on Toxoplasmosis is from 2007. The tone is a little odd for something so horrific but they get quite a bit of interesting science across in 5 minutes.

Toxoplasmosis, suicide and brain cancer

In addition to the effects I mentioned in class Toxoplamsosis has also been linked to increased rates of suicide: Toxoplasma gondii Seropositivity and Suicide Rates in Women
In conclusion, the results suggest that a positive relationship between rates of infection with T. gondii and suicide is apparent in women of postmenopausal age. Prospective studies are necessary to further confirm this association predictively and to explore mechanisms mediating this relationship.

and brain cancer -
Incidence of adult brain cancers is higher in countries where the protozoan parasite Toxoplasma gondii is common.
Infection with T. gondii was associated with a 1.8-fold increase in the risk of brain cancers across the range of T. gondii prevalence in our dataset (4–67%). These results, though correlational, suggest that T. gondii should be investigated further as a possible oncogenic pathogen of humans.

Both these papers are from 2011. It's pretty clear there's something going on even if we don't know exactly what it is.

Illusory superiority

I was curious what proportion of road accidents were caused by driver error rather than, say, brake failure. Although I suspected the proportion would be high I was surprised it was as high as 93%. In fact the majority of accidents are solely due to driver error.

What is alarming is that numerous surveys have revealed that whilst, in reality we are all only human (and get distracted, make mistakes and fall asleep), most of us believe we are brilliant drivers.

In the United States for example, when asked to compare their driving safety and skill to other people 93% of people put themselves in the top 50%. This is apparently known as 'Illusory Superiority'.

I wonder how long it will be before someone tries to use Toxoplasmosis infection as a defense against a charge or reckless driving or something similar. It's really not that different to the Twinkie defence.