A new tick-borne virus, named Asian longhorned tick nairovirus (ALTNV), has been identified in China, with cases reported in four provinces including Hubei, the origin of the COVID-19 outbreak. Scientists detected the virus in 329 patients who suffered from severe flu-like symptoms, including gastrointestinal issues and low platelet counts.
The Asian longhorned tick, identified as the primary carrier of ALTNV, is an invasive species that has been reported across 21 states in the U.S., particularly in the Northeast and South. It is currently unclear if the virus has also made its way to the U.S.
Discovery and Symptoms
Researchers in Beijing analyzed samples from over 3,000 individuals who presented with fever after a tick bite. Of these, 10.4 percent tested positive for ALTNV. The study, published in the New England Journal of Medicine, found that among patients infected solely with ALTNV, the most common symptoms after fever were fatigue (84 percent) and gastrointestinal issues (80 percent). Thrombocytopenia, a low platelet count that can lead to fatal internal bleeding, was present in 38 percent of these patients.
Scientists also investigated the coinfection of ALTNV with dabie bandavirus (DBV), also known as severe fever with thrombocytopenia syndrome. DBV is a serious infection with a fatality rate of approximately 15 percent. In a group of 38 patients coinfected with both viruses, seven individuals, or 18.4 percent, died. These coinfected patients were more likely to experience severe symptoms, including respiratory problems and kidney impairment.
The earliest documented case of ALTNV dates back to 2009. While none of the patients infected only with ALTNV died, seven patients who had ALTNV along with another virus did not survive. Researchers noted that tick-borne viruses can prompt immune cells to destroy platelets, which are essential for blood clotting.
Tick Presence and Transmission
Further analysis of approximately 47,000 ticks collected from 15 provinces in China revealed that 1.3 percent tested positive for ALTNV, with 1.75 percent of Asian longhorned ticks carrying the virus. Laboratory studies have shown that Asian longhorned ticks can transmit the virus to mice, suggesting a potential for human transmission.
The Asian longhorned tick was first identified in the U.S. in November 2017 in Hunterdon County, New Jersey. Since then, it has been found in states ranging from New York to Georgia and as far west as Missouri. The tick has also established itself in countries like Australia and New Zealand.
There are no specific treatments for either ALTNV or DBV. Patients with DBV are typically treated with intravenous fluids and blood transfusions. Researchers continue to monitor the spread and impact of ALTNV in affected regions.