High Seroprevalence and Risk Factors of Crimean-Congo Hemorrhagic Fever Virus in Camels at Livestock Markets in Border Regions, Nigeria, 2023-2024.

BACKGROUND

Crimean-Congo hemorrhagic fever (CCHF) is a highly fatal, tick-borne zoonosis in humans for which no licensed vaccines exist. Camels are important hosts of Hyalomma ticks, yet data on their role in CCHF epidemiology in Nigeria are limited. This study assessed seroprevalence and risk factors of the CCHF virus (CCHFV) in camels from major livestock markets in northern Nigeria.

MATERIALS AND

METHODS

From June 2023 to July 2024, 812 camels were sampled during 54 weekly visits to Maiduguri (Borno), Maigatari (Jigawa), and Illela (Sokoto) livestock markets. Epidemiological data (sex, age, origin, and tick infestation) were recorded for each sampled camel. Serum samples were tested using ID Screen CCHF double antigen Enzyme-linked immunosorbent assay (ELISA) kits. Descriptive statistics and logistic regression were applied to identify predictors of seropositivity (p < 0.05).

RESULTS

CCHFV antibodies were detected in 89.4% of camels (95% CI: 87.1-91.4%). Prevalence was highest in Maiduguri (94.2%), followed by Maigatari (92.0%) and Illela (80.4%). Females (94.1%) had higher seropositivity than males (84.9%), and adults (>48 months) exceeded younger camels (94.3% vs. 81.7%). Tick infestation was strongly associated with seropositivity. Multivariable analysis showed younger age (OR = 0.35, 95% confidence intervals [CI]: 0.19-0.66), male sex (OR = 0.33, 95% CI: 0.18-0.60), and absence of ticks (OR = 0.45, 95% CI: 0.26-0.81) were significantly linked to reduced odds of seropositivity.

CONCLUSION

The very high seroprevalence observed in camels suggests that they may contribute to the epidemiology of CCHF in northern Nigeria. Although cultural practices such as consumption of raw camel milk and urine are common, their role in CCHFV transmission remains uncertain; therefore, further studies are recommended to investigate their potential epidemiological significance. Strengthening One Health-based surveillance, vector control, and public education is critical to reducing zoonotic transmission and protecting human and animal health.