F A Ramadhan, G P Omondi, P A Otiende, C Mutisya, M N Wanjira, I O Akhulunya, J Parsein, I L Lekolool, E M Kingori, E A Cook, B Bett, C O Oyieng', H K Njaanake
High CCHFV seroprevalence in cattle indicates its endemicity in pastoral regions and the associated risks to communities due to their unique sociocultural practices. Furthermore, these findings reveal an increased occupational risk for abattoir workers from the silent circulation of CCHF. Our results underscore the importance of abattoir-based surveillance and highlight the need for targeted interventions through a One Health approach.
INTRODUCTION: Crimean-Congo Haemorrhagic Fever Virus (CCHFV) is a tick-borne virus of significant public health concern, especially in endemic regions such as East Africa. Despite its zoonotic potential, there is a paucity of data on its occurrence and risk factors among high-risk populations in Kenya. This study aimed to determine the seroprevalence of CCHFV among cattle and workers at an abattoir, and to characterize putative risk factors and CCHF spatial distribution in Kenya.
METHODS: We conducted a cross-sectional study testing 366 cattle from Dagoretti slaughterhouses and 313 archived human serum samples for anti-CCHFV antibodies using the ID Screen CCHF Double Antigen Multispecies ELISA kit. For cattle, we collected metadata on source counties, sex, ownership, body condition score and breed, while for human participants, additional metadata included occupational exposures, safety and health training and personal protective equipment use. We used multivariable logistic regression to examine the association between seropositivity and potential risk factors and choropleth maps to visualize cattle seropositivity across source counties.
RESULTS: The overall CCHFV seroprevalence was 42.6% (95% CI: 37.7%, 47.9%) in cattle and 4.8% (95% CI: 2.7%, 7.8%) in slaughterhouse workers. Among cattle, seroprevalence was highest in animals from pastoral counties (43.8%, 95% CI: 37.9%, 49.9%) and among crossbreeds (52.4%, 95% CI: 29.8%, 74.3%). In humans, seropositivity was slightly higher in males (5.2%, 95% CI: 2.7%, 9.0%) and older age groups (7.4%, 95% CI: 3.7%, 12.8%). Use of overalls was significantly associated with reduced odds of seropositivity (aOR = 0.199, 95% CI: 0.051-0.978, p = 0.027). Spatial analysis revealed high seroprevalence in cattle originating from arid and semi-arid counties.
CONCLUSIONS: High CCHFV seroprevalence in cattle indicates its endemicity in pastoral regions and the associated risks to communities due to their unique sociocultural practices. Furthermore, these findings reveal an increased occupational risk for abattoir workers from the silent circulation of CCHF. Our results underscore the importance of abattoir-based surveillance and highlight the need for targeted interventions through a One Health approach.