Risk of Crimean Congo haemorrhagic fever virus (CCHFV) introduction and spread in CCHF-free countries in southern and Western Europe: A semi-quantitative risk assessment

Abstract

Crimean-Congo hemorrhagic fever (CCHF) is a severe tick-borne viral zoonotic disease caused by Crimean-Congo hemorrhagic fever virus (CCHFV). The disease is usually asymptomatic in domestic and wild animals, both of which may act as reservoirs of the virus. CCHF is endemic in parts of Africa, Asia, the Middle East and Eastern Europe. During the last decade, the emergence or re-emergence of CCHF was described in several countries in the Eastern Mediterranean Region, with an increasing risk of extension into new areas. Given the public health importance, this study undertakes a semi-quantitative risk assessment to analyse the likelihood of entry and exposure of CCHFV into 9 CCHF-free countries in Southern and Western Europe. Based on a framework outlining the probability of the virus entry and exposure, the risk estimates were assessed for each individual country. The risk assessment was performed using information from public databases and the available scientific literature. The likelihood of entry was conducted considering 3 main pathways: infected tick vectors, wildlife and livestock. The likelihood of exposure was assessed considering the probability of survival of the infected ticks once introduced in CCHF-free countries (depending on abiotic and biotic factors), and the exposure of resident uninfected susceptible ticks to infected imported wildlife and livestock. The risk estimates (combined CCHFV introduction and exposure) were low for the majority of the countries (Austria, Belgium, Germany, Luxembourg, Netherlands, Slovenia and Switzerland) and medium for France and Italy, if accounting only for animal health consequences. Considering the public health consequences only, the risks were rated low for all the countries, except for Italy where it was assessed to be medium.

Multisectoral Perspectives on Global Warming and Vector-borne Diseases: a Focus on Southern Europe

“…tick, it is not difficult to see the link between the high prevalence of Q fever in Southern Europe and GW. Crimean-Congo hemorrhagic fever (CCHF) is also another TBDs that have emerged or re-emerge in some countries in Southern Europe with sign showing an expansion of the disease to new area in line with warmer climate due to GW [ 95 , 96 ].…”

“…Their expansion from the Mediterranean region of France to colder part of France (Northern) can be attributed to GW as Northern France is witnessing warmer climate than before due to CC. In a study by Fanelli and Buonavoglia [ 95 ], France is one country at high risk of entry of CCHF, a TBD transmitted by Hyalomma marginatum species. Though this risk of entry was attributed to migratory birth [ 82 , 99 ].…”

Crimean-Congo hemorrhagic fever: a growing threat to Europe

“…Although, France and Italy have not yet reported human cases of CCHFV, high CCHFV seroprevalence has been reported in livestock in Corsica [30] and CCHFV RNA has been detected in a tick from a migratory bird in Italy [31]. Importantly, both countries were estimated to be at medium risk for introduction and exposure to CCHFV [32].…”

“…Bien que la France et l'Italie n'aient pas encore signalé de cas humains de CCHFV, une séroprévalence élevée du CCHFV a été signalée chez le bétail en Corse [30] et l'ARN du CCHFV a été détecté dans une tique provenant d'un oiseau migrateur en Italie [31]. Il est important de noter que les deux pays ont été estimés à un risque moyen d'introduction et d'exposition au CCHFV [32].…”

Viral hemorrhagic fevers - a recurrent public health threat

“…The slaughtering and butchering of slaughtered animals poses a particular risk of virus transmission to humans [23]. The area where the infectious disease occurs is wide and includes Europe (Balkans), Africa (mainly central and northeastern) and Asia (western areas of China, Pakistan, Afghanistan, Middle East) [27][28][29]. In Europe, human cases of infection have been reported in Albania, Armenia, Bulgaria, Kazakhstan, Kosovo, Russia, Serbia, Tajikistan, Turkey, Turkmenistan, Ukraine and Uzbekistan.…”