The spatial pattern of human exposure to Crimean–Congo haemorrhagic fever virus is not consistent with red deer‐based risk predictions

Abstract

The objective of this study was to evaluate the spatial risk of exposure to Crimean-Congo haemorrhagic fever virus (CCHFV) infection of healthy blood donors in an enzootic region with a predicted risk gradient based on a virus-animal interaction risk model. We designed a cross-sectional study to test if the exposure pattern of the human population to CCHFV spatially matches the predicted risk. We randomly selected 1384 donors from different risk gradients and analyzed their sera searching for CCHFV antibodies. None of the selected blood donors showed exposure to CCHFV.This study shows that exposure risk spatial patterns, as predicted from animal-tickvirus models, does not necessarily match the pattern of human-infected tick interactions leading to CCHFV infection and CCHF cases, at least in a region of predicted moderate infection risk. The findings suggest that future studies should bear the potential drivers of tick-human encounter rates into account to more accurately predict risks.

Determinants of Crimean–Congo haemorrhagic fever virus exposure dynamics in Mediterranean environments

“…Some of the first questions to be solved after the emergence of human cases of CCHF in Spain and the resulting alarm, such as the distribution and presence of CCHFV, have been resolved (Cuadrado‐Matías et al., 2022 ; Frías et al., 2022 ; Monsalve Arteaga et al., 2021 ; Moraga‐Fernández et al., 2021 ; Sánchez‐Seco et al., 2022 ). However, many aspects of the ecology of the virus remain unresolved and they are essential to prevent CCHF cases.…”

Animal Exposure Model for Mapping Crimean-Congo Hemorrhagic Fever Virus Emergence Risk

“…If risk for infection is higher for an animal in a territory, it is also higher for a person in that territory because the virus is transmitted mainly by tick bites to animals and humans. The factors that predispose human contact with infected ticks or animals will determine the actual risk for CCHFV infection ( 12 ), although risk will be greater in areas more environmentally favorable for virus transmission. Our results provide public health authorities with information about which areas of Andalusia have the highest risk for CCHFV transmission for anyone linked to small ruminant production.…”

“…Identifying spatiotemporal virus transmission hotspots may provide information for surveillance and prevention strategies to reduce exposure to CCHFV. Although the likelihood of virus exposure within the general population is low ( 12 ) because of a predominantly urban lifestyle, greater accuracy in risk prediction may lead to more effective preventive measures for the at-risk population ( 13 ).…”