Risk factors associated to bovine brucellosis seroprevalence in the eastern region of Paraguay

Amaias Avalos; Benoit Durand; Felipe Mendoza; Carlos Ramirez; Victor Maldonado; Gina Zanella

doi:10.1016/j.prevetmed.2023.105979

Risk factors associated to bovine brucellosis seroprevalence in the eastern region of Paraguay

Prev Vet Med. 2023 Sep:218:105979. doi: 10.1016/j.prevetmed.2023.105979. Epub 2023 Jul 26.

Authors

Amaias Avalos¹, Benoit Durand², Felipe Mendoza³, Carlos Ramirez⁴, Victor Maldonado⁴, Gina Zanella⁵

Affiliations

¹ Paris-Est University, Anses, Laboratory for Animal Health, Epidemiology Unit, Maisons-Alfort, 94700, France; Université Paris-Saclay, Faculté de Médecine, 94270, Le Kremlin-Bicêtre, France.
² Paris-Est University, Anses, Laboratory for Animal Health, Epidemiology Unit, Maisons-Alfort, 94700, France.
³ National University of Asuncion, Faculty of Veterinary Sciences, Paraguay.
⁴ National Animal Health and Quality Service (SENACSA), General Directorate of Animal Health, Identity and Traceability, Paraguay.
⁵ Paris-Est University, Anses, Laboratory for Animal Health, Epidemiology Unit, Maisons-Alfort, 94700, France. Electronic address: gina.zanella@anses.fr.

PMID: 37544080
DOI: 10.1016/j.prevetmed.2023.105979

Abstract

In Paraguay, whose main economic activity is cattle raising, bovine brucellosis is an endemic disease. Between May 2019 and October 2020, a national prevalence survey was implemented by the Paraguayan Veterinary Services. In the frame of that survey, a cross-sectional study was conducted in the eastern region of Paraguay to identify the risk factors that could be associated with brucellosis-positive farms and to estimate the bovine brucellosis seroprevalence and farmers' awareness about the disease. A questionnaire was administered to farmers to collect data on potential risk factors for bovine brucellosis as well as awareness on the disease. A logistic regression model was used to identify the risk factors associated with a farm brucellosis positive status. Blood samples were collected from 2551 cattle on 133 farms. The overall apparent seroprevalence was 27.8 % (95 % CI: 20.4-36.3 %) at the farm level, and 5.5 % (95 % CI: 4.7-6.5 %) at the animal level. Among 18 potential risk factors, four were associated with a farm brucellosis positive status. Farm size was associated with a higher risk of positive status in medium (20-80 cows) and large farms (>80 cows), compared with small farms (<20 cows). Barn disinfection had a protective effect on the risk of positive status. Conversely, presence of dogs and not incinerating/burying aborted material increased this risk. Even if 89 % of the farmers acknowledged being aware of the bovine brucellosis transmission to humans, only 46% of these farmers declared using protective gloves during calving or when handling abortions. The findings of this study emphasize the importance of implementing biosecurity measures and proper disposal of aborted material to control the disease. Therefore, to control the disease in Paraguay, vaccination campaigns should be accompanied by awareness campaigns addressing good farm management practices to minimize the risk of introduction and maintenance of brucellosis as well as the risk of human infection.

Keywords: Brucella; Brucellosis; Cattle; Paraguay; Prevalence; Risk factors.