The staff of the TSU Biological Institute, in joint research with the Federal Service for Supervision of Consumer Rights Protection and Human Well-Being “Vector”, has found a rare and poorly studied Altai hantavirus in the Tomsk Region for the first time. The carrier of the hantavirus was a type of shrew. Hantaviruses are fraught with the danger of hemorrhagic fever. In 2019, an outbreak of this infection occurred in the Saratov Region, where 1,500 people fell ill. During the new field season, TSU biologists will continue to study potential carriers of hantaviruses, in order to prevent mass diseases in people.
- The Altai hantavirus was detected in biomaterial collected in 2019. The analysis was carried out by the specialists of the Federal Service “Vector” (Novosibirsk), says Alexander Zhigalin, a member of the Laboratory of Biodiversity Monitoring, associate professor at the TSU Biological Institute. - Traditionally, the red vole and field mouse are considered the main carrier of hantaviruses in Russia. However, other mammals are able to spread these pathogens, so in 2019 we began to conduct a targeted study of insectivores for the presence of hantaviruses.
The material collected during the fieldwork will highlight the rare virus genome and describe it. This is necessary to understand the origin of the pathogen, to develop testing systems, and most importantly, to find ways to treat the infection that it can cause.
Hantavirus infection occurs through contact with small mammals and their waste products. As a rule, human infection in Eurasia ends with the development of hemorrhagic fever with renal (HFRS) or pulmonary (HPS) syndrome . Hantavirus infections are widespread in the northern hemisphere, but in 2019, the largest outbreak of hemorrhagic fever in the 21st century occurred in Russia in the Saratov region. HFRS cases were recorded in other regions of the country.
- The risk group includes residents of summer cottages and private houses, pickers of wild plants, fishermen, hunters, tourists, and those who often relax in nature,- explains Alexander Zhigalin. -However, last year’s outbreak showed the vulnerability of the townspeople, as the mass reproduction of the carriers of the infection occurred due to the lack of proper attention of the authorities to the improvement of the urban environment, in particular, to the uncontrolled appearance and growth of unauthorized dumps.
More than 40 species of hantaviruses are currently known. Their methods of penetrating the human body are similar to those of coronaviruses; however, these are different families wjith different structures. Moreover, only isolated cases of transmission of hantaviruses from person to person have been recorded, but for coronaviruses that is the main route.
For many years, rodents - voles, mice, rats, and others - played a leading role in the spread of hantaviruses (the most common viruses in Russia are Puumala and Hantaan). However, studies by TSU biologists found that shrews can significantly contribute to maintaining focal hantavirus infections. Samples collected in several areas of the Tomsk Region showed that up to 50% of these insectivores can be carriers.
Shrews are as widespread as rodents. They often settle in summer cottages, in private houses, or on the first floors of apartment buildings, gravitating to places of mass accumulation and breeding of insects. This creates the prerequisites for infection in various categories of people.
The TSU scientists’ results suggest the need for further research not only for fundamental science but also to obtain objective information about the spread of viruses that cause mass outbreaks and lead to deaths. However, such work requires significant funding for expeditionary work and laboratory analysis.
- Now all pathogens have remained in the shadow of the coronavirus, so it’s very difficult to get financing from scientific funds,- says Alexander Zhigalin. - At the same time, it is long-term studies that help us not only to identify the general level of vector infection in advance but also to monitor the emergence of new pathogens. The foci of natural infections are extremely dynamic and require constant close attention. Only by possessing information about their functioning can researchers and doctors prevent both local outbreaks of infections and those that can spread to large areas.
In the current field season, biologists intend not only to continue the study of insectivores but also to begin the study of bats. According to scientists, in 2019-2020 the number of shrews increased markedly. Warm winters also contributed to population growth.
Most often, outbreaks of diseases from hantavirus infections occur in spring, summer, and early autumn, when the number of carriers of the pathogen increases. To prevent infection, it is necessary to observe personal hygiene measures: work at the summer cottage or outdoors with gloves on, wash hands after working, and use a respirator or mask when work is related to the formation of aerosols (a mixture of air with dust or soil).
Owners of summer cottages and private houses must carry out landscaping and prevent clutter. Deadwood, foliage, and debris create the prerequisites for the active reproduction of rodents and insectivores. Also, such conditions contribute to an increase in the number of ticks, which increases the risk of tick-borne infections.