CCHFV detected in Hyalomma ticks in western Spain with 1.54% infection rate

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Frontiers in Medicine Published April 4, 2026 Medically reviewed April 26, 2026 Study authors: Patricia Sánchez-Mora, Miguel A. Habela, Teresa del Peso, Ana Candela Grande Ávila, Ana María García… DOI ↗ By Dr. Amelia Tan, PhD · Internal Medicine & Chronic Disease

Key Takeaway

Note CCHFV circulation in Hyalomma ticks in western Spain; supports surveillance in endemic areas.

A retrospective surveillance study analyzed 3,183 ticks, grouped into 1,569 pools, collected from wild ungulates, livestock, domestic animals, and vegetation in central and southern Cáceres, western Spain. The study aimed to detect and genetically characterize Crimean-Congo hemorrhagic fever virus (CCHFV).

CCHFV was exclusively detected in Hyalomma lusitanicum ticks. The overall infection rate was 1.54% (95% CI: 1.14–2.03). Most positive pools originated from wild ungulates, with red deer being a notable source. Genetic analysis revealed the circulation of two CCHFV genotypes, predominantly genotype III.

Safety and tolerability data were not reported for this ecological study. Key limitations, including potential sampling biases or methodological constraints, were also not reported. The study did not involve a human or clinical intervention, so direct patient-level safety conclusions cannot be drawn.

The practice relevance is restrained to public health surveillance. The authors emphasize the need for continuous monitoring in endemic areas to assess animal and public health risks. This study provides baseline ecological data on viral presence and diversity but does not establish human infection risk or clinical outcomes.

Study Details

Study typeCohort

EvidenceLevel 3

PublishedApr 2026

View Original Abstract ↓

Crimean-Congo hemorrhagic fever virus (CCHFV) was first detected in Spain in ticks collected from red deer in southwestern Cáceres. Since then, this region, established as endemic, has been the focus of several surveillance studies. However, updated data on viral circulation in this area remain limited. We conducted a retrospective surveillance study to assess the presence and genetic diversity of CCHFV in ticks collected in central and southern Cáceres over multiple years (2017 and 2020–2024). A total of 3,183 ticks, grouped into 1,569 pools, were collected from wild ungulates, livestock, domestic animals and vegetation, and analyzed by two PCR methods. Positive pools were characterized by Sanger sequencing. CCHFV was exclusively detected in Hyalomma lusitanicum ticks, with an overall infection rate of 1.54% (95% CI: 1.14–2.03). Most positive pools originated from wild ungulates, particularly red deer. Genetic analysis revealed the circulation of two CCHFV genotypes, predominantly genotype III. The detection of CCHFV in ticks collected over multiple years supports the sustained circulation of the virus in southwestern Cáceres. Our findings also reinforce the key role of H. lusitanicum as the main vector maintaining the virus in wild ungulates and underscore the genetic diversity of circulating strains and the importance of using multiple molecular methods. These results emphasize the need for continuous surveillance in endemic areas to monitor viral circulation and assess animal and public health risks.