Originally from Central Asia and Africa, this “Hyalomma marginatum” tick, larger than normal ticks, is advancing more and more in France and the Mediterranean basin, and in addition to Lyme disease, can transmit Crimean hemorrhagic fever. Congo, potentially fatal for humans.
It measures 8 mm, larger than the 1 to 5 mm of our most common ticks: “Hyalomma marginatum”, nicknamed the “giant tick”, is progressing in France as in the Mediterranean countries.
A hemorrhagic fever dangerous for humans
This new tick, in addition to the “classic” Lyme disease, can carry the Crimean-Congo hemorrhagic fever virus (CCHF), a potentially fatal disease for humans, and can cause fever, chills, digestive disorders and, in rare cases, serious forms with uncontrolled bleeding or organ failure, reports Public Health France.
Although no deaths have been recorded in humans in France, around ten human cases have been recorded and deaths noted in Spain, where the tick has been present since 2013, according to ANSES. Fortunately, cases are rare, because its mortality rate is high in humans (around 10% to 40%, on average 3 cases of contamination out of 10 are fatal). Given its dangerousness, this virus can only be handled in a P4 type laboratory.
Proven establishment or detected presence, 20 departments concerned
In France, where “Hyalomma marginatum” has been present since 2015 via Corsica, samples of these ticks were taken from cattle in the Pyrénées-Orientales. As of May 23, the presence of this giant tick was confirmed in 11 departments, including 4 in Occitanie, i.e. two more than in August 2023 :
- Alpes-Maritimes,
- Ardèche,
- Aude,
- Bouches-du-Rhône,
- South Corsica,
- Drome,
- Gard,
- Upper Corsica,
- Hérault,
- Eastern Pyrenees,
- Var
Public health France
According to Ouest France, its presence has been detected in at least 9 other departments, including two in Occitanie:
- Alpes de Haute Provence
- High mountains
- Lozere
- Tarn
- Landes
- Charente
- Indre-et-Loire
- Loiret
- Ain
Recognizable by its two-colored legs, this giant tick adapts better than other ticks to more humid climates and temperature variations, notes UFC Que Choisir. Its expansion in France means that the risk of emergence of Crimean-Congo hemorrhagic fever in the territory is “real”, warns ANSES.
