Deadly risks from new carriers This subtropical species of ticks is increasingly spreading

Dangerous subtropical tick species first detected in Austria

Health experts have reported increasing numbers of ticks in recent months. In the meantime, non-native species also appear here. In Austria, for the first time, a subtropical species of ticks has been detected that can transmit the life-threatening Crimean Congo fever virus. Even in Germany, the "giant ticks" have already been discovered.

Risk to public health

The World Health Organization (WHO) has for years been publishing a list of diseases and pathogens that "pose a risk to public health and for which there are no or inadequate countermeasures," as the organization writes on its website. For these diseases, "accelerated research is urgently needed given their potential to cause a public health emergency and the lack of effective drugs and / or vaccines". One of these diseases is the Crimean Congo fever. It can be infected by a species of ticks, which was now detected for the first time in Austria.

In Austria, the subtropical tick species Hyalomma marginatum has been detected for the first time. These ticks can transmit a deadly disease. They are significantly larger than native species. (Image: IMB / Lidia Chitimia-Dobler)

Carriers of life-threatening Crimean Congo fever virus

As the University of Veterinary Medicine Vienna writes in a statement, the tick species Hyalomma marginatum is mainly located in the Mediterranean, Asia and North Africa.

However, larvae and nymphs of the dangerous bloodsuckers are also transferred to northern Europe from their traditional range of migratory birds in the spring.

However, the prevailing climate in our latitudes prevented the further development of the transmitter of the life-threatening Crimean Congo fever virus.

The above-average warm summer, however, contributed to the fact that researchers from the University of Hohenheim in Stuttgart and their colleagues at the Institute for Microbiology of the German Armed Forces (IMB) in Munich this year have detected several specimens of this type of tick.

The comparatively large animals with the strikingly striped legs had appeared in the Hanover region, in Osnabrück and in the Wetterau, probably introduced via birds.

In a statement, the experts stated that they feared that the bloodsuckers could establish themselves here.

Sexually mature parasite found in Austria

In addition to babesia, single-celled, eukaryotic parasites, these ticks can also transmit dangerous bacteria such as Rickettsia aeschlimannii and viruses such as the Thogot virus or West Nile virus and the life-threatening Crimean Congo fever virus.

For the first time, a sexually mature parasite was found in Austria and confirmed by experts from Vetmeduni Vienna.

Although the subtropical bloodsucker had no Crimean Congo fever in the luggage, but according to a joint analysis of Vetmeduni Vienna, the Austrian Agency for Food Security (AGES) and the Meduni Vienna, the equally relevant bacteria Rickettsia aeschlimannii.

Human-relevant pathogen detected

According to the information, the find of the tick species was reported by attentive horse owners from the Melk area.

The confirmation of the species was first done by morphological examination under the microscope and by a specific DNA, as well as the following review for human-relevant pathogens.

The Crimean Congo fever virus could be excluded. Nevertheless, a human-relevant pathogen was detected with Rickettsia aeschlimannii.

"The above-average warm and dry conditions in summer and the also very warm autumn meant that the soaked nymphs could develop themselves into otherwise inappropriate areas to adult ticks, presumably still in too small numbers to establish itself fixed," said Georg Duscher from the Institute of Parasitology of the Vetmeduni Vienna.

"However, there is a good chance that the more developed and more robust adult animals can survive the winter. We will know more about this in the spring. The detection of even fewer adult ticks represents a potential hazard, as can be seen in the infection with rickettsia, "said the scientist.

No acute warning signal

Although a proof in combination with the fourth warmest heat period in Central Europe may not be an acute warning signal at first.

But it confirms that the adult parasites can evolve from the previous stages at a corresponding temperature profile in Central Europe. This should trigger a rethink, according to the experts.

"The connection with migratory birds should be given more attention. It is also important to establish a regulated screening and to have the right detection methods also for the possibly introduced pathogens. The same applies to therapy and control measures, "said Franz Allerberger of the AGES.

Because the dangerous thing about this species of ticks is undoubtedly that, in addition to Rickettsia or West Nile, it can transmit Crimean Congo fever viruses.

That's why AGES has set up a special website that informs about different types of ticks and the potential dangers they can pose.

Fatal outcome of the disease can be prevented

The Crimean Congo fever has recently attracted attention due to several cases in Turkey but also in Spain.

This disease is caused by a viral pathogen that belongs to the Arboviruses and causes a hemorrhagic fever. It is also important because there is no vaccine yet.

However, timely treatment with an anti-viral agent can prevent the fatal outcome of the disease.

"We were pleasantly surprised that pet owners have reacted so attentively. Hyalomma ticks can morphologically differ from their native ones, "said Duscher.

"However, it is unlikely that so much attention will be paid outside of expert circles," the scientist said.

"But we see this as a positive trend that both alertness and interest in the population are given. This makes it easier for us to screen for new and dangerous types of ticks and shows that information sharing works. "(Ad)