Scientists have identified a new tick-borne virus, named Wetland virus (WELV), which can infect humans and, in some cases, impact the brain. The virus was first detected in a patient from Jinzhou, China, in June 2019, who experienced fever, headache, and vomiting after a park visit in Inner Mongolia, where he had been bitten by ticks.
Discovery and Spread:
– The patient’s condition did not improve with antibiotics, suggesting a non-bacterial infection. Subsequent analysis of his blood revealed a previously unknown orthonairovirus, a group that includes several tick-borne viruses like the one causing Crimean-Congo hemorrhagic fever. – WELV had not been seen in either animals or humans before this case. Researchers began a search for the virus in ticks and animals from the park and surrounding areas, collecting nearly 14,600 ticks. About 2% of these tested positive for WELV genetic material, with the highest detection rates in the Haemaphysalis concinna tick species. – The virus was also found in some sheep, horses, pigs, and Transbaikal zokor rodents, though not in dogs or cattle. However, some of these animals had antibodies against the virus, indicating past exposure.
Human Impact and Research Findings:
– Blood tests of forest rangers and hospital patients revealed WELV antibodies in a small percentage of samples. In patients who developed fevers after tick bites, 20 tested positive for WELV. Symptoms included fever, dizziness, headache, and in severe cases, coma. Lab results showed tissue damage and blood clotting in many cases. – In laboratory mice, WELV caused severe infections affecting multiple organs, including the brain, supporting the notion that the virus can lead to serious neurological conditions in humans.
The researchers conclude that WELV is pathogenic to humans and circulates among humans, ticks, and various animals in northeastern China. Enhanced surveillance and detection of emerging orthonairoviruses are essential for better understanding their impact on human health.
