Short Report: Update on <scp>CCHFV</scp> Seroprevalence in Mauritanian Camels and Cattle Sampled Between 2020 and 2021

OBJECTIVES: Crimean-Congo hemorrhagic fever virus (CCHFV) is a zoonotic tick-borne virus causing severe and potentially fatal disease in humans, with case fatality rates of up to 30%. In contrast, domestic ruminants and camelids remain asymptomatic. Since the first reported case in Mauritania in 1983, CCHFV antibodies have been repeatedly detected in humans and animals. This study aimed to assess the local circulation of CCHFV in camels and cattle in southern Mauritania and in Nouakchott. METHODS: A total of 317 blood samples (174 cattle, 143 camels) were collected from southern regions bordering Mali and Senegal (n = 170) and from Nouakchott (slaughterhouse and animal market; n = 147). Sera were analyzed at the ONARDEP laboratory using the ID Screen CCHF Double Antigen Multi-species ELISA. The effects of age, species, sex and sampling year on seropositivity were evaluated using a generalized linear mixed-effects model (GLMM). RESULTS: Overall seroprevalence was 70% (222/317). Camels showed a higher seroprevalence (> 81%; 117/143) than cattle (> 60%; 105/174). Increasing age was significantly associated with higher seropositivity. Age and species had significant effects on CCHFV antibody status. Descriptive age-specific seroprevalence increased with age in both cattle and camels, whereas sex and sampling year showed no significant effect. CONCLUSIONS: Crimean-Congo haemorrhagic fever remains an endemic zoonosis and a significant public health threat in Mauritania and neighbouring countries. Our findings confirm high CCHFV seroprevalences in cattle and camels in the study area. However, important knowledge gaps remain regarding virus circulation and transmission dynamics. Strengthening diagnostic capacity, conducting integrated epidemiological studies across livestock, ticks and humans, and enhancing awareness and regional surveillance are essential for a better understanding and control of CCHFV spread.