Significantly increased number of Hantavirus infections in Baden-Württemberg
Hantaviruses are probably rather unknown to most Germans and usually only a few hundred people in Germany develop an infection each year. In some years, however, the spread of viruses has increased significantly, which is accompanied by a massive increase in the number of infections reported.
The Robert Koch Institute (RKI) has currently noticed a significant increase in Hantavirus infections compared to the previous year, with individual regions such as Baden-Württemberg being particularly badly affected. The number of reported hantavirus infections there increased more than fivefold in the first quarter compared to the previous year. According to the RKI, the number of registrations has increased significantly across Germany.
Fluctuating virus activity of the hantaviruses
While 2016 was a rather positive year with 282 reported hantavirus infections, a total of 2,824 infections were reported to the RKI in 2012. This shows the fluctuations in virus activity. In 2017, the experts from the Baden-Württemberg State Health Office now expect the spread of infections to increase again. In a special Hanta prediction model, 2,447 Hantavirus infections were forecast for Baden-Württemberg alone.
Dramatic increase in the number of cases
In the first eleven weeks of 2017, the RKI had more than 134 Hanta virus infections, compared to 38 infections in the same period last year. The State Health Office of Baden-Württemberg expects Hantavirus activity to increase significantly in the coming weeks. With 66 cases (as at the end of March), a drastic increase compared to the previous year can already be seen (13 infections in the same period).
Causes of the increased virus activity
According to the State Health Office, the beech forests in many regions of Baden-Württemberg form an "endemic area for hantaviruses and have experienced several hantavirus epidemics in the past few years." This is where the main transmitters of the viruses, the red vole (other types of mouse also serve as the hosts). . These feed preferably on beech nuts. If there are a particularly large number of beech nuts in a year, the mice can then reproduce extremely and with them the Hantaviruses. "The frequency of the disease varies from year to year and is probably dependent on the density and the contamination of the local rodent population", explains the RKI.
Infections from rodent excretions
Humans usually become infected through the excretions of the animals, which can be inhaled, for example, with whirled up dust. The pathogens common in this country cause flu-like symptoms when infected, with high fever, headache, abdominal pain and back pain, reports the RKI. In the further course, a drop in blood pressure and finally kidney dysfunction can also lead to acute kidney failure, the experts warn. However, fatalities are rather rare among the European Hantavirus types, in contrast to the virus variants that are common in North and South America.
Viruses are relatively stable in the environment
According to the RKI, hantaviruses are generally found worldwide. The name is derived from the Korean border river Hantan, where during the Korean War in the early 1950s, more than 3,000 soldiers fell ill with a severe hemorrhagic fever. The virus was finally isolated for the first time in 1977. Various rodents are considered to be the natural hosts of the viruses, and the RKI reports that the infected rodents excrete the viruses via saliva, urine and faeces. The viruses are relatively stable in the environment and therefore no direct contact with the rodents is necessary to infect them.
Hantaviruses are distributed in different ways in Germany
According to the RKI, Hantaviruses that cause illness are transmitted to humans primarily from red vole and fire mice. Possible other virus reservoirs include yellow-necked mice, field mice, earth mice and the rat. There is probably no human-to-human transmission. The infections can be found in all age groups, although middle-aged men are affected more often than women, and Hantavirus infections are not equally common in Germany, reports the RKI. According to the RKI, areas in which there is an increased risk of being infected with Hantaviruses include “the Swabian Jura, the Osnabrück area, Lower Franconia, the Odenwald, Upper Swabia, the Franconian Jura, the Bavarian Forest, East Hesse and West Thuringia. "(Fp)