While for many global warming seems to be a harbinger of greater opportunity, such as the discovery of mineral and oil resources, for scientists in general it raises grave questions as to what those changes may wreak on the human species.
In Siberia, just as in Alaska, the permafrost layers have been melting at a frightening pace. In Alaska entire villages and islands are sinking into the ground or being swept away as the ice barriers have melted away.
In Siberia, the melting of deep ice layers and permafrost is also releasing a worrisome bounty. Corpses of dead from ancient and modern ages alike are likely to bring back pathogens long defeated by man, such as smallpox.
Some of the bodies have already surfaced, and are being harvested for scientific purposes. Covered in black soot from the frozen tundra and the centuries of entombment in the permafrost, the bodies have been wrapped in plastic and sometimes reburied in haste to avoid possible contamination.
One of the things that is becoming clear is that some of the bodies are of people who died of smallpox, a disease that was eradicated in the 1970s, thanks to a massive vaccination campaign, and could become the vehicle for a new epidemic, since many people are no longer vaccinated for the disease. Mass vaccinations stopped in the mid 1970s making entire generations vulnerable to the disease.
The virus, in fact, can survive the cold of the icy Siberian ground, and could very easily be let loose if some of the bodies are exposed and not found by researchers and disposed of properly.
In one particular area of the tundra, in the high latitudes, there are bodies scattered from what scientists believe was a smallpox epidemic. Since their number is not known, and precise locations are hard to determine, there is very real possibility that either animal or human could come in contact with them.
Smallpox was one of the deadliest and most dreaded disease in man's history. It has one of the highest mortality rates, and disfigures horribly anyone who survives it. It was such a scourge, that it produced the first vaccine ever made, in 1796, by scientist Edward Jenner, to combat it.
Even in recent times, smallpox killed an immense number of people, more than the black plague. Just in the 20th century, 300 million people died of smallpox before mass vaccinations ensued in the 1960s. The last known case of smallpox was in Ethiopia in the 1970s. Since then, only laboratories in the US, UK and Russian hold the last viable specimens.
Those labs that still have the limited stock of smallpox virus for research, are themselves a possible vehicle for infection, but a much less possible one when compared to the bodies lying in the Siberian tundra. At this moment, the only younger generations that have been vaccinated against the disease are the American armed forces personnel.
Twenty years ago, however, the first body was found near the Kolyma river. The headless corpse was found amidst the bucolic background of the Kolyma river, by people trying to find mammoth bones and other bounty that washes down from the river. When the headless body was found, scientist battled a swarm of mosquitoes ubiquitous in the tundra and immediately sent the alarm not to touch the corpse.
The finding of smallpox scarred corpses has happened before. Fortunately most of them have been handled properly, although one construction worker did contract it when demolition of a building that had housed smallpox patients centuries before released the virus into the air. That alone can give an indication of how resilient the virus is. And it is especially resilient when preserved in ice.
But as thawing accelerates through the effects of global warming, the possibility of the release of the virus into the population becomes ever greater. In fact scientists had observed as far back as the 1950s how Variola, the smallpox virus, was perfectly preserved at very low temperatures for a number of years.
In the 1980s a cache of frozen bodies was found and analyzed. Although fears were quelled when none of them presented positive for the virus, the analysis of the remains showed that some of the bodies carried antibodies to the virus.
There is much action presently aimed at destroying the remaining stockpiles of laboratory smallpox as we go farther away in time from the last mass vaccinations. Some cite the possible thawing of the tundra as a reason, while others advocate destroying the caches just on principle, since they too constitute a threat.
Although many scoff at the possibility that the virus survived for centuries in a frozen state, there is much evidence that bacteria and other organisms have survived for millions of years in a frozen state, especially in permafrost environments.
In Siberia alone, scientists have mapped an area twice the size of the state of California where the permafrost has thawed and given way to slumped, lake filled landscapes. Methane gases trapped in the tundra in turn accelerate global warming, and so on.
Some scientists think that warmer climates actually play in favor of the smallpox virus degrading and becoming unviable. That's because smallpox can only survive for a few days after being unfrozen. However, permafrost is not always the same in different localities. In some places permafrost is ice rich, while in other it is dry, where the bodies could be even better preserved.
Other scientists also contend that global warming will allow the spread of existing pathogens such as malaria and Leishmaniasis to previously temperate or colder climates.
While some think that a full blown epidemic of smallpox is not a reality due to the virus' slow progression and the fact that it is only infectious when the pustules are evident and open, others are not so sanguine.
The reality of global warming is yet to be written.
The reality of global warming is yet to be written.
Op-Ed
Source : Live Science: 3.10.14
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