What is Alongshan?

The first time the Alongshan virus (ALS virus or ALSV for short) was detected was in 2017 in a hospital in Inner Mongolia. The patient was bitten by a tick and exhibited symptoms typical of TBE infection. However, neither the TBE virus nor its antibodies could be detected in the blood. After further testing, the patient was found to have the novel ALSV. In 2019, ALSV was also discovered in Finland and finally in Switzerland in late 2022.

Alongshan virus belongs to the flavivirus family, which also includes the TBE virus, dengue virus, Zika virus, and many more. Symptoms usually seem to present themselves similarly to those of a cold or at the beginning of a TBE infection:

• Headache
• Fever
• Fatigue
• Muscle pain
• Joint pain

Skin or brain inflammation is typical for TBE, but does not seem to be characteristic for an ALSV infection. In addition, all results indicate that the disease is transmitted by ticks, but mosquitoes cannot be excluded as vectors. ALSV RNA was detected in mosquitoes in Jilin Province in northeastern China. This RNA was found to be related to the RNA found in the ticks examined.

Alongshan virus detected in Swiss ticks

On December 6, 2022, a research team at the Vetsuiss Faculty of the University of Zurich announced that they were able to detect ALSV in Swiss ticks for the first time. They were also able to isolate the complete viral genome sequence, a necessary step for the development of a diagnostic test.

The tick samples were collected in between 2021 and 2022 in different regions of Switzerland, which means that the tick virus has been spreading in Switzerland for some time. The ALS virus was even detected more frequently than the TBE virus.

However, there is still no data on the number of cases in Switzerland, because the symptoms are very similar to those of a TBE infection and testing for ALSV is difficult. Even so, Prof. Dr. Cornel Fraefel, Director of the Virological Institute of the Vetsuisse Faculty at the University of Zurich, states that a sudden increase in the number of cases is unlikely.

Detection in blood is difficult

The first choice for detecting a virus in the blood is usually the PCR method, which is now familiar to everyone through COVID. Depending on the virus, the blood is examined for RNA or DNA, i.e. the virus genome.

However, since viruses in blood are often very unstable, direct detection is difficult and a negative PCR does not necessarily mean that no infection has occurred. Therefore, Prof. Fraefel's research team is currently working on a more reliable diagnostic procedure: an antibody test. This involves testing the blood for virus-specific antibodies, which the body produces as soon as it comes into contact with a virus. This procedure can often be simpler and faster to use.

Once the test is established, screenings are performed on patient samples. If ALS virus-specific antibodies or nucleic acids are indeed detected, diagnostic laboratories in Switzerland will also test for ALS virus in the future as part of TBE virus diagnostics.

How can you protect yourself?

Since there is currently neither a standardized detection method nor a vaccine against ALSV, the best way to protect yourself is to tackle the problem at its source and try to prevent tick bites from the beginning. When venturing out into nature, no matter for how short an amount of time, we recommend wearing long clothing and spraying yourself with tick sprays for skin and clothing.

In addition, we strongly recommend to get vaccinated against TBE or to check if the vaccination needs to be refreshed. Even though the TBE vaccine was not developed for the ALSV, you should at least make sure you are protected against one of the viruses. After all, you definitely don't want to fall ill with both at the same time.

If you are unsure whether you need to refresh your TBE vaccination or whether the vaccination is even an option for you, please feel free to contact us for a consultation. To do so, please book an appointment for "Just-a-Shot".

You can find more information about protection from annoying bites in our blog post about Mosquito and Tick Protection.