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Seroprevalence of Rift Valley fever in cattle of smallholder farmers in Kwilu Province in the Democratic Republic of Congo

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Abstract

Rift Valley fever (RVF) is a zoonotic mosquito-borne disease caused by RVF virus (RVFV) that causes abortions and high mortalities in livestock and is also associated with acute and fatal disease in humans. In the Democratic Republic of Congo (DRC), information on the epidemiology of RVF is limited, particularly among cattle reared by smallholder farmers. This cross-sectional study was conducted to investigate the seroprevalence of RVF in cattle raised by smallholder farmers in Kwilu Province of DRC, which has not yet reported an RVF epidemic. A total of 677 cattle sera were collected from four territories and tested for anti-RVFV antibodies using immunofluorescent assay and enzyme-linked immunosorbent assay. The overall seroprevalence of anti-RVFV IgG was 6.5% (44/677) (95% CI 4.81–8.7). There was a statistically significant difference in the seroprevalence among the territories (χ2 = 28.79, p < 0.001). Territory seroprevalences were as follows: Idiofa 14.08% (95% CI 9.78–19.76), Bulungu 4.14% (95% CI 1.83–8.68), Gungu 3.21% (95% CI 1.41–6.78), and Masi-Manimba 1.19% (95% CI 0.06–7.37). Seroprevalence differed significantly among age categories (p = 0.0017) and ecosystem (p < 0.001). The seroprevalence of animals aged between 1 and 2 years was 20.0% (95% CI 8.4–39.13) and was higher than group aged <1 year, between 2 and 3 years, and > 3 years. Forest area (18.92% (95% CI 12.35–27.7)) had higher seropositivity than savannah area (4.06% (95% CI 2.65–6.12)). Sex difference was not significant (χ2 = 0.14, p = 0.704). These findings indicate that cattle in Kwilu Province had been exposed to RVFV, which represents a significant risk for both livestock and human health.

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Acknowledgments

We would like to thank the Ministry of Agriculture Breeding and Fisheries of the Democratic Republic of Congo for their support in carrying out this study. We are also grateful to officials of the Provincial Ministry of Agriculture, Fisheries and Livestock and to cattle farmers in Kwilu Province for their support.

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Author notes

  1. Abdel-Amir Dib Halawi and Ngonda Saasa contributed equally to this work.

Authors and Affiliations

  1. Department of Biology, Faculty of Sciences, National Pedagogic University, Matadi/Liberation Street, Ngaliema, Kinshasa, Democratic Republic of Congo

    Abdel-Amir Dib Halawi, Mutambel Hity & Luamba Lua Nsembo

  2. Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia

    Ngonda Saasa, Ayato Takada, Aaron S Mweene & Edgar Simulundu

  3. Division of Global Epidemiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan

    Boniface Lombe Pongombo, Masahiro Kajihara & Ayato Takada

  4. Central Veterinary Laboratory, Wangata Street, Gombe, Kinshasa, Democratic Republic of Congo

    Boniface Lombe Pongombo

  5. Faculty of Veterinary Medicine, National Pedagogic University, Matadi/Liberation Street, Ngaliema, Kinshasa, Democratic Republic of Congo

    Boniface Lombe Pongombo

  6. Department of Veterinary Services, Ministry of Fisheries and Livestock, Chilanga, Zambia

    Herman Moses Chambaro

  7. Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, 001-0020, Japan

    Herman Moses Chambaro & Hirofumi Sawa

  8. Department of Microbiology, Division of Life Science, Regional Center for Nuclear Studies, University of Kinshasa, Kinshasa, 11-868, Democratic Republic of Congo

    Mutambel Hity

  9. Global Station for Zoonosis Control, Global Institution for Collaborative Research and Education (GI-CORE), Hokkaido University, Sapporo, Japan

    Hirofumi Sawa & Ayato Takada

  10. Global Virus Network, Baltimore, MD, USA

    Hirofumi Sawa

  11. Africa Centre of Excellence of Infectious Diseases of Humans and Animals, University of Zambia, Lusaka, Zambia

    Aaron S Mweene

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  1. Abdel-Amir Dib Halawi
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Correspondence to Abdel-Amir Dib Halawi.

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This study was approved by the Ministry of Agriculture, Fisheries and Livestock, Local Politico-Administrative Authorities. Consent for blood sample collection using conventional methods from cattle herds was obtained from owners.

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Halawi, AA.D., Saasa, N., Pongombo, B.L. et al. Seroprevalence of Rift Valley fever in cattle of smallholder farmers in Kwilu Province in the Democratic Republic of Congo. Trop Anim Health Prod 51, 2619–2627 (2019). https://doi.org/10.1007/s11250-019-01978-z

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