Abstract:
Crimean–Congo haemorrhagic fever virus (CCHFV) is the causative agent of CCHF, a
fatal viral haemorrhagic fever disease in humans. The maintenance of CCHFV in the ecosystem
remains poorly understood. Certain tick species are considered as vectors and reservoirs of the
virus. Diverse animals are suspected as amplifiers, with only scarce knowledge regarding rodents
in virus epidemiology. In this study, serum samples from febrile patients, asymptomatic livestock
(cattle, donkeys, sheep, and goats), and peridomestic rodents from Baringo (Marigat) and Kajiado
(Nguruman) counties within the Kenyan Rift Valley were screened for acute CCHFV infection by
RT-PCR and for CCHFV exposure by ELISA. RT-PCR was performed on all livestock samples in
pools (5–7/pool by species and site) and in humans and rodents individually. CCHFV seropositivity
was significantly higher in livestock (11.9%, 113/951) compared to rodents (6.5%, 6/93) and humans
(5.9%, 29/493) (p = 0.001). Among the livestock, seropositivity was the highest in donkeys (31.4%,
16/51), followed by cattle (14.1%, 44/310), sheep (9.8%, 29/295) and goats (8.1%, 24/295). The
presence of IgM antibodies against CCHFV was found in febrile patients suggesting acute or recent
infection. CCHFV RNA was detected in four pooled sera samples from sheep (1.4%, 4/280) and four
rodent tissues (0.83%, 4/480) showing up to 99% pairwise nucleotide identities among each other.
Phylogenetic analyses of partial S segment sequences generated from these samples revealed a close
relationship of 96–98% nucleotide identity to strains in the CCHFV Africa 3 lineage. The findings
of this study suggest active unnoticed circulation of CCHFV in the study area and the involvement
of livestock, rodents, and humans in the circulation of CCHFV in Kenya. The detection of CCHF
viral RNA and antibodies against CCHFV in rodents suggests that they may participate in the viral
transmission cycle.
Description:
DATA AVAILABILITY STATEMENT : The metadata supporting the results of this study are available upon request from the authors. The data are not publicly accessible due to the privacy of the research participants, especially the febrile patients and livestock farmers. The partial sequences of the S segment were deposited in GenBank under the accession numbers: OQ357265-OQ357272.