A Countrywide Seroepidemiological Survey of Rift Valley Fever in Livestock, Uganda, 2017
Author:
Nyakarahuka Luke12, Kyondo Jackson1, Telford Carson3, Whitesell Amy3, Tumusiime Alex1, Mulei Sophia1, Baluku Jimmy1, Cossaboom Caitlin M.3, Cannon Deborah L.3, Montgomery Joel M.3, Lutwama Julius J.1, Nichol Stuart T.3, Balinandi Stephen1, Klena John D.3, Shoemaker Trevor R.3
Affiliation:
1. Department of Arbovirology, Emerging and Reemerging Infectious Diseases, Uganda Virus Research Institute, Entebbe, Uganda; 2. Department of Biosecurity, Ecosystems and Veterinary Public Health, Makerere University, Kampala, Uganda; 3. Viral Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, US Centers for Disease Control and Prevention, Atlanta, Georgia
Abstract
ABSTRACT.
In 2016, an outbreak of Rift Valley fever was reported in the Kabale District in Uganda for the first time in 48 years. Three human cases were confirmed by polymerase chain reaction, and subsequent serological investigations revealed an overall IgG seropositivity of 13% in humans and 13% in animals. In response to this reemergence, we designed a countrywide survey to determine the seropositivity of anti-Rift Valley fever virus (RVFV) IgG antibodies in livestock. Samples were collected from 27 districts and tested for RVFV anti-IgG antibodies. A total of 3,181 livestock samples were tested, of which 54.4% were cattle (1,732 of 3,181), 34.3% were goats (1,091 of 3,181), and 11.3% were sheep (358 of 3,181). Overall RVFV seropositivity was 6.9% (221 of 3,181). Seroprevalence was greater in cattle (10.7%) compared with goats (2.6%) and sheep (2.0%), among females (7.5%) compared with males (5.2%), and among adults (7.6%) compared with juveniles (4.9%) and nurslings (6.4%). Exotic breeds and animals with a history of abortion or stillbirth also had greater odds of RVFV seropositivity. Animals grazed under tethering and paddocking had greater RVFV seropositivity compared with animals that grazed communally, and livestock in the western and eastern regions had the greatest seroprevalence. In a multivariate regression model, animal species (odds ratio [OR], 6.4; 95% CI, 3.5–11.4) and age (OR, 2.3; 95% CI, 1.4–3.6) were associated significantly with RVFV seropositivity. This study could be important in developing risk-based surveillance for early outbreak detection to limit the spread of RVFV in both human and animal populations.
Publisher
American Society of Tropical Medicine and Hygiene
Subject
Virology,Infectious Diseases,Parasitology
Reference22 articles.
1. Rift Valley fever virus epidemic in Kenya, 2006/2007: the entomologic investigations;Sang,2010 2. Epidemiology and serological detection of Rift Valley fever disease in farm animals in southern Egypt;Mahmoud,1877 3. Rift Valley fever seroprevalence and abortion frequency among livestock of Kisoro district, South Western Uganda (2016): a prerequisite for zoonotic infection;Budasha,2018 4. Seroprevalence of Rift Valley fever in cattle along the Akagera–Nyabarongo rivers, Rwanda;Gafarasi,2017 5. First laboratory-confirmed outbreak of human and animal Rift Valley fever virus in Uganda in 48 years;Shoemaker,2019
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