Tick-borne viruses are gaining increasing attention as their geographic range expands and previously unrecognized pathogens continue to be discovered. While established pathogens, like tick-borne encephalitis virus and Crimean Congo haemorrhagic fever virus each cause approximately 12,000 symptomatic human infections yearly, numerous novel tick-borne viruses have recently been identified, but little is known about their circulation and clinical relevance. Among those is the Jingmen virus group, often referred to as “Flavi-like viruses”, because their non-structural proteins closely resemble those of classical flaviviruses. Unlike flaviviruses, however, Jingmen viruses possess a segmented RNA genome. One member of this group, Alongshan virus (ALSV), was first isolated in 2017 from a patient presenting with tick-borne-encephalitis-like illness in Alongshanzhen, China, and was subsequently detected in 85 additional patients with a history of tick bites from the same region. Since its discovery, surveillance studies have identified ALSV in ticks across an increasing number of countries, including Russia, Finland, Germany, Switzerland, France, and more recently Poland, Spain, Italy and the United Kingdom. As reports accumulated, we asked ourselves whether ALSV was also present in Austria, and, if so, how long it had been circulating unnoticed. Equally important, has virus circulation also resulted in human infections? To answer these questions, we investigated the distribution and persistence of ALSV in Austria and searched for evidence of human exposure.
Screening approximately 4,800 ticks collected throughout the country revealed ALSV RNA in around 20 samples from multiple regions, showing that the virus is widely distributed. The retrospective analysis of archived tick samples then revealed that Alongshan virus was already present in Austria in 2005. Virus sequences obtained from the same region in western Austria in 2005 and 2024 showed high similarity, indicating longstanding local circulation for at least twenty years. We next looked for evidence of human infection. Although virus RNA was not detected in any of the nearly 2,000 samples collected from individuals following tick bites, two individuals had high titers of Alongshan virus specific IgG-antibodies in the absence of detectable IgM, consistent with prior, previously unrecognized infection.
Together, these findings show that ALSV has circulated unnoticed in Austria for a long period and provide the first evidence of human exposure to ALSV outside China. They also underscore the need for advanced diagnostics for novel tick-borne and other arboviruses, including highly specific serological assays. Such diagnostic tools will be essential for strengthening surveillance and preparedness for future emerging viruses.
Original article:
Florian, David M.; Jetzinger, Paul; Schötta, et al. Widespread circulation of Alongshan virus in Austria and serological evidence for infection in humans: a nationwide molecular and serological observational study. The Lancet Microbe. Volume 7, Issue 8101404August 2026. 10.1016/j.lanmic.2026.101404