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25.08.2016

The Yamal authorities have been struggling with an outbreak of anthrax also known as “Siberian plague”. This dangerous disease was last seen in the region 75 years ago, and experts believe it has been triggered by unusually warm weather in the Arctic region. Experts also warn that global warming might not only unleash long-forgotten diseases of the 18th-19th centuries but also cause some new so-called paleo-infections, which a modern man has not encountered yet. The warmer climate has begun thawing the permafrost soil, and some lurking bacteria can be unlocked.

One of Russian leading experts in virology Sergey Netesov, Doctor of Biology, Professor, Corresponding Member of the Russian Academy of Sciences, the Head of the Laboratory of Bionanotechnologies at Novosibirsk National Research University (Novosibirsk, Russia) took part in the satellite TV link-up between Moscow, Saint Petersburg, Yakutsk and Novosibirsk organized by TASS. Specialists discussed possibilities of new infection threats caused by climate change. Sergey Netesov tells us about anthrax and ways of fighting it.

“We have several dozens of anthrax-like infections fixed with animals around the world – in France, Australia, Sweden and some countries of Africa and Asia. However, the outbreak of the disease in Russia is the biggest in the number of the dead animals and people infected. Any infection outbreak should be dealt with very seriously, with precautionary measures taken such as vaccination of the animals and the people who contacted them, utilizing the infected animals, burning their corpses at high temperatures in order to kill the bacteria, disinfecting the places where the animals were kept and, of course, warning people about the ways how the infection can spread and informing them on safety precautions.”

Anthrax is a rare infection spread by spores of the Bacillus anthracis bacteria, which occurs naturally and can be ingested by livestock and passed to humans, usually through skin contact, causing black lesions. If left untreated, it can be fatal. The recent outbreak of the disease in Yamal is considered to be caused by abnormally high temperatures in the region reaching +35C (95F). The warmer climate has begun thawing the permafrost soil and unleashing the bacteria spores, which infected the reindeer while grazing. The infection could spread from the corpses of long-buried infected reindeer that were uncovered as the permafrost melted. So far, 2,349 infected reindeer are reported to have been burned in the special operation to halt the spread of the outbreak, and about 160 people have been evacuated from the quarantine area. Ninety nomadic herders, including 53 children, were hospitalized in the town of Salekhard. So far 23 adults and children have been diagnosed with the disease with one 12-year-old boy having died. According to the Federal Service on Surveillance for Consumer rights protection and human well-being, the situation is under strict control.

Being a natural focal infectious disease, anthrax is sporadically fixed on the territories of more than 90% countries all over the world. It is spread not only through infected food and contacts with infected animals. One sheep collector from Scotland, for instance, got infected from the mort bought at an open-air market in Africa in order to use it for his musical instrument.

“About 15 years ago,” says Sergey Netesov, “a shepherd from Novosibirsk region had his cow grazing on the territory of an old anthrax burial site, where his cow got infected and died. The shepherd decided to sell the meat, and the slaughterer got infected with a cutaneous anthrax. Fortunately, it was diagnosed very quickly and the person recovered. Serious measures were taken in time. All the cattle were vaccinated and all the old burial sites were mapped again. Anthrax has not been fixed on those territories any longer.”

The disease is quite rare but very dangerous. The expert points out that people should have some kind of a behavior reflex. If they notice some symptoms of anthrax in their cattle, they should immediately call for a vet or an epidemiologist rather than trying to utilize the animal by themselves.

“Global warming can bring us some new diseases as well,” warns Sergey Netesov. “West Nile encephalitis is just one of the examples. It is at the door.”

His colleagues from Moscow share this view. Sergey Semenov, director of Russia’s Rosgidromet Institute of Global Climate and Ecology, relates this outbreak to the warmest spring and summer in the Arctic ever since systematic weather observations began. “Temperatures on Yamal climbed above 30 degrees Celsius, which was 8 degrees higher than normal. It differs a lot from previous years.”

Viktor Maleyev, deputy chief of Russia’s Central Research Institute of Epidemiology, considers the number of the people infected with anthrax exceptionally high. The usual number does not exceed one or two people per year. “Anyway, climate change causes the spread of diseases such as Zika fever, dengue, chikungunya fever and other exotic virus infections. Why does it happen? The main factor is the El Niño Southern Oscillation (commonly called ENSO), which is associated with a band of warm ocean water in the central and east-central equatorial Pacific. It causes global changes of both temperatures and rainfall and influences the number of mosquitoes which carry viruses around. By the way, the outbreaks of cholera that we witness from time to time are also caused by climate change.”

The recent trend in research done by specialists from the Central Research Institute of Epidemiology of the Federal Service on Customers' Rights Protection and Human Well-being Surveillance (Moscow) and other research institutes is to study not only human infections, but also infections spread among animals, insects, etc. Ticks or mosquitoes, for example, can carry several diseases at the same time. The expert says that before sending Russian sportsmen to the Olympic Games in Rio, scientists visited the site to check the insects for infections.

Victor Maleyev adds that infections spreading in the south may well move northwards, due to the climate change, and “settle” on new territories. “Apart from permafrost degradation, which seems to have caused the present outbreak, some other dangers are waiting to attack. There are some graveyards with people who died of smallpox or burial sites of mammoths with unknown diseases. Climate change is likely to surprise us in different ways, and we should be ready to face the challenge.”

Mikhail Grigoriev, Deputy Director of the Permafrost Studies Institute, SB RAS, blames the practices of burying infected animals as the main cause of the Yamal tragedy. “They didn’t bury deep because it’s hard to dig deep in permafrost,” he explained. He also suggested that an expert commission should be organized, which would investigate the case and try to minimize the consequences and the damage.

Boris Kershengoltz, chief of research at the Institute for Biological Problems of Permafrost Zone, SB RAS, warns that some very dangerous infections from the 18th-19th centuries may return with permafrost thawing. Sites where animals are buried are of special danger. Mammoths’ viruses’ pathology has not been studied yet, and nobody knows how those microorganisms can behave in new conditions.

He also emphasized that climate change and warming in the Arctic region as well as permafrost thawing are self-simulating processes. It is accompanied by methane outbursts, a strong greenhouse gas, with methane hydrate released not only in the north shelf but also in the Tundra. “What is going on Yamal is just a bell,” says the researcher.

Professor Valery Malinin, an oceanologist from Russia’s Hydrometeorological Institute, adds that it is the unbalanced climate that causes dangerous hydrometeorological processes. “The Arctic region is considered as the kitchen of global weather. I would say, the northern polar area is the kitchen of our climate. During the recent 20 years we can estimate the number of disasters causing great economic losses to increase twofold (e.g., floods in Krymsk in Krasnodar Krai, on the Amur River, in the Altai Mountains, as well as droughts in other areas).”

Summing the talk up, Sergey Netesov linked the success of fighting such outbreaks with financing science. “I hope, the situation on Yamal will make our authorities finance research of highly infectious diseases. In order to develop effective prevention, we should find out the real causes of the outbreak. We should be aware of tropical infections as well, as they will come sooner or later, and we should have diagnostic agents for them developed and proven.”

Text and photo prepared by Marina Moskalenko.

Last edit: 31.08.2016 10:17