Snippets: Disease X, Bird Flu, and the 7,000-year affair

‘Disease X’

WHO revealed that 10 of the 12 samples taken from those ill with ‘Disease X’ in Kwango province tested positive for malaria. Testing continues. But given that, as previously mentioned, this is a region with a lot of malnutrition and where respiratory virus rates are rising, it’s looking more likely that this is not an ‘outbreak’ at all, but rather an unfortunate confluence of events. Look at it this way: the problem was noted in November, and it’s partially solved already. That’s great news: public health systems are working!

When sapiens met neanderthalensis

Two different papers, one in Nature and one in Science conclude from study of aDNA (that is, genetic data from ancient remains) that when modern humans left Africa a small group of them interbred with a small number of Neanderthal groups over a roughly 7,000-year period. The Nature paper showed that Neanderthal DNA found in almost all ancient and present-day non-Africans came from one “pulse” of interbreeding that happened somewhere around 45,000 to 49,000 years ago. In other words, most of those H. sapiens groups that left Africa and did not interbreed did not survive—did Neanderthal genes confer some evolutionary advantage or was it just that most groups, including so me that had interbred, died and so our ancestors were just lucky?

That’s part of what the Science paper sought to answer. They “analyzed genomic data from 59 ancient individuals sampled between 45,000 and 2200 years before present and 275 diverse present-day individuals to study the evolutionary history of Neanderthal ancestry throughout time” and the result “suggests that the gene flow occurred from a single or multiple closely related Neanderthal groups. By contrast, the earliest modern humans […] possess substantial unique Neanderthal ancestry and a distinct matching profile to the sequenced Neanderthals, indicating that some Neanderthal ancestry in these early individuals is not shared with modern humans after 40,000 years.” When they looked at the frequency of Neanderthal ancestry across the genome and over time, they “uncovered new candidates of adaptive introgression, including regions that were immediately adaptive for modern humans and some that became adaptive more recently from introgressed standing variation.” The conclude, “We found strong support for a single extended period of Neanderthal gene flow into the common ancestors of all non-Africans that occurred between 50,500 and 43,500 years ago […] The majority of natural selection—positive and negative—on Neanderthal ancestry happened very quickly after the gene flow and left clear signals in the genetic diversity of the earliest modern humans outside Africa.”

Livescience has a pretty good explainer.

H5N1

So, one more time for the people in the back: DO NOT CONSUME RAW MILK OR RAW MILK PRODUCTS. EVER. See the last three points:

A study published this week suggest that cats can serve as mixing vessels for reassortment of avian and mammalian flu.Another study indicates Mongolian horse herds are (super scientific term) positively seething with H5N1 antibodies but seem to be asymptomic. Which means it could be spreading madly but no one thought to look. Until now.A child in California who drank raw milk may have been sick with H5N1. They tested positive for influenza A (which includes H5N1). Testing could not show H5N1, though, so it’s not being added to the national registry. Their symptoms were fever and vomiting. Fortunately, they have recovered.In Los Angeles County, two cats developed symptoms after consuming milk from Raw Farms. They tested positive for influenza A (which is rare in cats) and testing is ongoing. Their symptoms included appetite loss, fever, and neurologic signs. Both died after their symptoms worsened.In Arizona, animals at the Wildlife World Zoo near Phoenix fed raw milk died: a cheetah, a mountain lion, swamp hen, an Indian goose, and a kookaburra. An infected white tiger appears to be improving after treatment. (Oh, and, according to APHIS—US Department of Agriculture’s Animal and Plant Health Inspection Service, that has a nifty map here, infections have also been confirmed in a coyote and a polar bear.)

Those last three piss me off. If you’re an adult and you choose to drink raw milk, then I think you’re a fool but it doesn’t make me angry. Kill yourself in whatever way you fancy. But children? And animals who have no choice? I hope whoever fed them that milk suffers eternal haemorrhoids.