Abstract
In 2016, an outbreak of anthrax killing thousands of reindeer and affecting dozens of humans occurred on the Yamal peninsula, Northwest Siberia, after 70 years of epidemiological situation without outbreaks. The trigger of the outbreak has been ascribed to the activation of spores due to permafrost thaw that was accelerated during the summer heat wave. The focus of our study is on the dynamics of local environmental factors in connection with the observed anthrax revival. We show that permafrost was thawing rapidly for already 6 years before the outbreak. During 2011–2016, relatively warm years were followed by cold years with a thick snow cover, preventing freezing of the soil. Furthermore, the spread of anthrax was likely intensified by an extremely dry summer of 2016. Concurrent with the long-term decreasing trend in the regional annual precipitation, the rainfall in July 2016 was less than 10% of its 30-year mean value. We conclude that epidemiological situation of anthrax in the previously contaminated Arctic regions requires monitoring of climatic factors such as warming and precipitation extremes.
Highlights
We analyzed the behavior of active layer thickness (ALT) from three Circumpolar Active Layer Monitoring (CALM) sites closest (200– 400 km) to the outbreak location (Novy Port, Fig. 1a): one to the north (Vaskiny Dachi, continuous permafrost), one to the south (Nadym, discontinuous permafrost) and one to the west (Vorkuta, discontinuous permafrost)
The dynamics of the active layer in Vaskiny Dachi show general agreement with the behavior of the mean annual air temperature (MAAT, see Methods) (Fig. 2b), as expected for the cold sites underlain by continuous permafrost (Smith and Riseborough 2002)
How Climatic Factors Contribute to the Anthrax Outbreak: An Outline
Summary
Anthrax has been known since ancient times with the first descriptions dating back to Hippocrates, fifth century BC (Schwartz 2009), and it is endemic to all the continents except Antarctica (Dragon and Rennie 1995; WHO 2008; Malkhazova et al 2019; Carlson et al 2019). The bacteria are sensitive to the moisture, acidity and organic content of soils, and their life cycles are influenced by climatic factors, such as ambient temperature and precipitation (Dragon and Rennie 1995; WHO 2008; Waits et al 2018; Walsh et al 2018; Malkhazova et al 2019; Carlson et al 2019). In the regions endemic for anthrax, high incidences occur during dry and warm periods following intensive precipitation, explaining localities of the major outbreaks in countries with warm climates such as Turkey, Ethiopia, South Africa etc. The vast geographical range of anthrax and risk of recurrence after years or even decades (Dragon and Rennie 1995) is due to high resistivity of spores to unfavorable conditions and their ability to effectively reproduce themselves (Driks 2009)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
