Sunday, February 21, 2016

Hansen's disease in ShagriLa

AlJazeerah has a nice article about Nepal's busy Leprosy hospital.

Despite the very low risk of infection, the stigma surrounding the disease can be extreme in Nepal. Patients are often isolated and abandoned by their families and communities in a country where the law prohibits infected people from working or marrying. In some rural areas, the disease is considered a curse from God as a punishment for sins committed in a former life.
a similar stigma is found in India, and was present in Europe and in the Bible.

Why? It is not very infectious, but it spreads quickly to children by skin to skin contact, and it leads to deformities that are ugly.

the clinic was founded by a British nurse, but the head doctor now is a local whose parents had the disease and he was raised in a lepersarium.

the disease is easily treated as an outpatient in places like Africa, where the stigma is less, but there is a need for inpatient treatment due to comorbidity (secondary infections of their wounds of example) and need to insure folks take their medicine (similar reason for TB hospitals). They also need specialized rehab work for their injuries and medical problems.

I say only one (mild) case in Zimbabwe, where outpatient treatment wiped it out, but there were still imported cases from Mozambique.

But there might be another reason for isolation.
Sister Humberta, one of our older nurses, had worked in one sanitarium. Once, when I had a patient with ulcers etc. and I asked her opinion if it was Hansen's disease, and she said no: It didn't stink like Leprosy. (it turned out to be ulcerated Kaposi's sarcoma, probably from HIV, which back then was not yet known about).

And in Liberia, I knew the doctor who ran the Hanson disease outreach. She had gone into easier work after the stress of working as a surgeon through the Nigerian civil war, and gotten her PhD in public health. Her job was to go to villages and find cases and put them on treatment, and then check them every three months or so that they were taking the medicines etc.

The outreach was funded by the Knights of Malta, a group beloved by conspiracy theorists.

The truth is more mundane: They are an "independent country" (which is now a mansion in Rome) and they issue their own passports.  UKIndependent article about that group.

. The 118,500 members, employees and volunteers are now in the charity business, working or supporting aid projects in some 120 countries on an annual operating budget of more than £150million.
Haiti, the Democratic Republic of the Congo, and most recently the Philippines, have all been recipients of its emergency relief. Most recently, it even started projects in Turkey, many of which support Syrian refugees, meaning that the eight-pointed Maltese Cross has returned to the modern incarnation of its old enemy.

y es, but conspiracy theories are more fun!

Friday, February 19, 2016

for later reading (blame colombus?)

an article on syphillis.

I'm too fuzzy minded to read it now, but the historical tracing of the epidemic from Columbus' sailors to Italy to the soldiers of Charles via the lovely Napolian ladies is pretty clear.

True, there may have been isolated cases before then, but given the promiscuity of the medieval days one does wonder why no one noticed it.

On the other hand, syphillis is related to yaws, which used to be common in Africa and spread by ordinanry skin contact. No, I've never seen a case. But early syphillis was a lot more virulent in the first hundred or so years it was in Europe, and could be spread by fairly innocuous ways like kissing (not deep kissing, but the cheek to cheek contact common those days when one greeted another, presumably via saliva containing germs and open skin...a few cases of HIV have been spread this way).

So is it new or old or just mutated?

More recently, Zuckerman was also part of a team that published a 2011 paper in the Yearbook of Physical Anthropology reviewing 54 different reports of treponemal disease in pre-Columbian Europe. None of the cases, they argued, presented evidence strong enough—either in the dating of the bodies or the signs of syphilis they displayed— to validate the pre-Columbian hypothesis.

and remember: They have found female DNA in a few people in Norway.

And of course, the cod fishermen would fish off the coast of Canada, so presumably could have visited the lovely ladies there.

Or did the Mali navy who got blown off course to Brazil catch it and bring it to Africa, or maybe they took yaws to Brazil? Remember, the "pristine rain forest" of the Amazon was very populated in those days with millions of farmers.

finally, even a rare case in China or Japan might have managed to get there via polynesians or just sailors who got blown off course.

The presence of African sweet potatoes in Polynesia sugggests that there were some contacts.

Saturday, February 13, 2016

Neanderthal DNA linked disease?

I only have a link to a summary, but this article claims that Neanderthal DNA is associated with a lot of diseases.

NASHVILLE, TENNESSEE—Researchers from Vanderbilt University used a database of 28,000 anonymous individuals, whose DNA samples were linked to their electronic health records, to look for Neanderthal DNA variants and see if they could be connected to modern health problems. “Our main finding is that Neanderthal DNA does influence clinical traits in modern humans: We discovered associations between Neanderthal DNA and a wide range of traits, including immunological, dermatological, neurological, psychiatric, and reproductive diseases,” evolutionary geneticist John Capra said in a press release

Problem number one:

Association does not mean causation.
It could be coincidence. And unless one proves the Neanderthal DNA was in the part of the genome that was associated with the disease, the question of coincidence is likely.
one example can be found in the newspaper article stating that Neanderthals were redheads, so that would explain why some Europeans had red hair. A closer examination showed that the genes were different.

Problem two: Neanderthal DNA varies by race.

it is higher in East Asians than Europeans, but is almost non existent in Africans

didn't Vanderbilt have DNA from African Americans?
Depression and addiction and autoimmune disease are present in African Americans too.

But then I see: "Actinic keratoses" (pre skin cancer lesions). Uh, this merely means someone is pale and goes out in the sun a lot. Again a racial trait due to melatonin (and yes, African albinos get skin cancer too). So do neanderthal genes increase the risk, or is it higher in whites, and white Europeans have more Neanderthal genes? (skin color seems to be paler in northern climates, e.g. Korea...think VitaminD deficiency and ricketts..the exception is those who eat fatty fish like salmon...e.g. Eskimos...think cod liver oil).

The immune problem seems to be identified with the location of the gene in other studies, but the rest of these sound like junk science.

UKMail article. suggests the "interbreeding" stuff might be more complicated than earlier articles suggest.

but what is not clear when they say "x percent" of humans have neanderthal genes, if they mean X percent of the population, or if 100 percent of folks have x percent of the Neanderthal dna.

from Natgeo

Everyone living outside of Africa today has a small amount of Neanderthal in them, carried as a living relic of these ancient encounters. A team of scientists comparing the full genomes of the two species concluded that most Europeans and Asians have between 1 to 4 percent Neanderthal DNA. Indigenous sub-Saharan Africans have no Neanderthal DNA because their ancestors did not migrate through Eurasia.

so back to the original article: Did they actually check out the gene or not?

 For example, a Neanderthal variant that increases blood coagulation may have sealed wounds more quickly and prevented infections. 
John Hawks article on DNA in populations.
Wonder what the percentages would show for Mongolians/Koreans/Native Americans, who were from Siberia, not Han Chinese.

guess I'll have to do a bit more study into this area, because right now I'm confused at what is being claimed.