Scientists discover new tick-borne virus after testing thousands of patients with mysterious illnesses
New Tick‑Borne Virus Discovered in China, Raising Calls for Better Diagnosis
Researchers in China have identified a previously unknown tick‑borne virus that can cause flu‑like illness, low platelet counts and liver inflammation.
In a study released this week in the New England Journal of Medicine, scientists from Beijing’s State Key Laboratory of Pathogen and Biosecurity reported finding the Asian longhorned tick nairovirus (ALTNV) in more than 10 % of patients who had been bitten by ticks. The virus, part of the orthonairovirus group, is genetically distinct from the Dabie bandavirus (DBV), a tick‑borne hemorrhagic fever that has been responsible for most severe cases in the region.
Symptoms and Clinical Course
Patients infected with ALTNV typically present with symptoms that mimic the flu: fever, muscle aches, fatigue and sometimes respiratory symptoms. Many also experience gastrointestinal upset. Laboratory tests frequently show thrombocytopenia—reduced platelet counts—as well as evidence of liver cell injury or inflammation.
Dr. Sharon Nachman, chief of pediatric infectious diseases at Stony Brook Children’s Hospital in New York, explained that “thrombocytopenia is low platelet count, so those patients bled, and it had about a 30 % mortality, which is quite high.” However, the study did not link ALTNV alone to severe bleeding or deaths. Fatalities occurred in patients who were co‑infected with DBV, a virus that can cause severe fever with thrombocytopenia syndrome.
In the group of patients who had both ALTNV and DBV, 18.4 % (seven patients) died. The co‑infection was also associated with increased respiratory problems and kidney complications, highlighting the danger of overlapping tick‑borne viruses.
Need for Improved Diagnosis
The authors of the study emphasized that the presence of both viruses in the same geographic areas, combined with a shared tick vector, “underscores the need for improved differential diagnosis between infections with these viruses in regions where SFTS is endemic.” They called for clinicians to consider multiple tick‑borne pathogens when evaluating patients with unexplained fever and thrombocytopenia.
Dr. Nachman noted, “The big picture is that ticks carry lots of viruses. We're getting smarter at identifying those viruses. And when one blood sample is negative, it's important to say, ‘Maybe there was a new virus there, and let's look for it.’”
Treatment and Prevention
Because effective antiviral drugs exist for influenza but not for many tick‑borne viruses—including the newly identified ALTNV—most patients receive supportive care to manage symptoms. “We certainly don't want to use antibiotics because those only work for bacteria, not for viruses,” Dr. Nachman said.
Preventing tick bites remains the best strategy. She advises wearing long pants tucked into socks, applying tick repellents to skin or clothing, and checking the skin for ticks after outdoor activities. “The longer the tick is on your skin, the more it’s engorged, the more it’s likely to pass an infection to you,” she explained. Removing a tick promptly after hiking or beach walks is critical.
ALTNV has not yet been detected in the United States. While the Asian longhorned tick is not present here, the country harbors many other tick species that carry diverse diseases. Dr. Nachman cautioned that “it’s not really about the ticks. It’s about the patient—who are you? What underlying illnesses do you have? How old are you, and how healthy are you?” These factors determine the severity of tick‑borne illnesses.
The discovery of ALTNV adds to the growing catalog of viruses carried by ticks worldwide. As research continues, public health authorities and clinicians will need to refine diagnostic tools and surveillance systems to keep pace with the evolving landscape of tick‑borne diseases.
