Doctors spoke about new tick-borne infections that appeared in Russia

Spring is the time when ticks become active, carrying a number of dangerous infections. According to statistics, every second Muscovite during the warm period will spend all his free time outside the city, where the risk of meeting with blood-sucking parasites is much higher. However, today ticks have spread in city parks. “MK” learned about what new tick-borne infections appeared in the country.

Every year, about half a million Russians (the figure fluctuates with a difference of plus or minus 20%) go to various medical institutions in the country about tick bites. In Moscow, 15-16 thousand calls are recorded per year. The peak of tick activity is in April-July, but you can meet with bloodsuckers in the forests near Moscow from February to November. This year, the ticks are more active due to the high snow cover, which allowed them to spend the winter in complete comfort.

“It has become warmer outside, the snow has melted, the vegetation is blooming – and the tick comes into an active state and begins to hunt for us,” says Gennady Onishchenko, the country’s former chief health officer. “Fortunately, there are not so many tick-borne infections, but often they are severe, with disability.”

The most terrible infection today is tick-borne encephalitis. The disease is transmitted through an infected tick, the first symptoms develop 7-12 days after the bite. The virus attacks the CNS. The onset of the disease is acute, with a sharp increase in body temperature up to 38-39 degrees, severe headache, nausea, and vomiting. There may be pain in the muscles, mainly in the neck, shoulders, thoracic and lumbar back, legs and arms. Much depends on the tick subtype – if it is Siberian or Far Eastern (they are mostly common in our country), the central nervous system will be affected in 50% of cases of infection, and if it is European (it is less common in our country) – in most cases the patient will get off with fever. Those who are constantly in the forest are most at risk of becoming infected: foresters, geologists, builders, hunters, tourists – for professional groups, vaccination against TBE is mandatory.

Onishchenko recommends that before going out into nature, ask if the region is endemic according to CE and whether anti-tick treatment of the territory of your SNT has been carried out. The bulk of the bites are recorded in the European part of Russia – but only because there is a high population density. Three districts of the Ivanovo region are endemic for CE in Russia, two in the Moscow region (Taldom and Dmitrovsky districts), 12 out of 37 in Tver, 18 out of 23 in Yaroslavl, 20 out of 25 in Arkhangelsk, 13 out of 18 in the Kaliningrad regions. The Vologda Oblast, Kaliningrad, Leningrad and Novgorod Oblasts are completely endemic. There are 48 endemic regions in total, mainly from St. Petersburg to the Far East, Altai and Kamchatka.

…Meanwhile, Russian scientists spoke about fundamentally new tick-borne infections that researchers have discovered in recent years. According to Lyudmila Karan, head of the scientific group for the development of new methods for diagnosing natural focal diseases of the Central Research Institute of Epidemiology, scientists all over the world are constantly studying both the ticks themselves and the materials of the patients they have attached to, in search of new infections. And regularly make sensational discoveries. Among the potentially dangerous newly detected tick-borne infections, Lyudmila Karan names the Jingman virus, the Alangshan virus, the Nuomin virus (aka the Forest virus), the Ezo virus and the Yamaguchi virus: “If a new virus is described somewhere in the world, and we have those species ticks that can be its carriers, we take it to work. We have a large collection of ticks collected from the western borders to the Far East – we analyze them for new infections. We can work with museum samples and even go back 20 years to make sure the virus is not entirely new.”

Yezo Virus first described in Japan in 2021 in two patients with symptoms of fever, and subsequently found in China in a patient material. All developed symptoms after being bitten by ticks. In 2023, a publication appeared on data from a study of 400 blood samples from people who fell ill after a tick bite in Mongolia: Ezo virus RNA was found in one sample. The patient had symptoms of fever, headache, shortness of breath, dizziness. Today it is known that about 4% of mites of the genus Hemophysalis in Japan are infected with a new virus, we also have such arthropods in the Far East and Siberia. A study conducted in different regions of Russia among more than 2.2 thousand ticks did not detect the Ezo virus, however, in the 2006 collection from the Kemerovo region, it was found in 1.5% of samples, and in samples from the Khabarovsk Territory, up to 4% of ticks contained this virus. Moreover, the Khabarovsk Ezo was almost the same as in Japan and China, and the Kemerovo turned out to be a separate line. Epidemiologists note that it is necessary to study the intermediate territories between the Far East and Western Siberia, especially the Altai Territory. “We are the third country to have confirmed a new virus. Perhaps this is not yet a very common infection, and so far, fortunately, we see only a feverish form. But a low percentage of infection does not mean that the proportion of patients is insignificant, ”the expert notes.

Virus Nuomin was almost simultaneously described in Japan and in Karelia, where it received the name “Forest”. In Japan, it was confirmed in 54 patients in 2017-2019. After that, the study of ticks began: it turned out that for different types of infection ranged from 2 to 8%, which is quite a lot. Studies carried out on the border between Russia and Mongolia showed that more than 60% of those infected with this virus are people 40-60 years old, and mostly men engaged in agriculture. Symptoms of the disease: fever, headache, loss of appetite, nausea, rash, aches, vomiting. Recently, in Russia, the virus has been found in 11 to 55% of ticks (for example, in the Kemerovo region – 30%). Tick ​​infection is said to be very high.

Jingman virus discovered in China in 2014 during the genome sequencing of ticks, today it has attracted great attention all over the world, it is being studied by many scientific teams. It has been found both in ticks and in the material of patients – today it has been found on all continents. For example, it was found in the blood of patients from the Rostov region – not yet massively, but research continues.

Longshan virus also first described in China, in 2017 – it causes a febrile illness in humans, very similar to that caused by Nuomin. “We explored Karelia, the Ulyanovsk region, Tatarstan, the Volga region – in all places, Alongshan was found in 6-8% of infected ticks. However, this virus has not yet been found in hospitalized patients after tick bites, although a group of patients with symptoms has been described in China, ”continues Karan.

Yamaguchi virus detected by the Japanese in 1.5-2% of ticks. While there is no evidence of human disease, the virus can be transmitted to mammals. It has not yet been found in Russian ticks.

Be that as it may, experts recommend protection. When going to the forest, Onishchenko advises to cover bare skin as much as possible, especially the neck. Upon arrival from a walk, conduct an examination of yourself and the children. “Women love to bring these bunches of flowering grass into the house. No need! A tick in the house will feel you and suck on you!” – the ex-sanitary doctor warns. If the tick still sticks, Onishchenko advises to remove it from the body as soon as possible and take it to the laboratory for analysis. Although modern doctors do not see any point in such an analysis – and are advised to monitor the symptoms.

And experts advise never to crush a tick – out of harm’s way. Some infections are transmitted in this way.