RESUMO
In 2021, the 88th General Session of the World Assembly of National Delegates to the World Organisation for Animal Health (OIE) recognized the estates of Acre, Paraná, the Rio Grande do Sul, and Rondônia as being free of foot-and-mouth disease (FMD) without vaccination. The certification was also extended to some cities in Amazonas and Mato Grosso. The new national strategic plan for 2026, which focuses on creating and maintaining sustainable conditions to expand FMD-free zones without vaccination, imposes new challenges and requires continuous evaluation of the FMD surveillance system. The objective of this research was to evaluate the FMD surveillance system in Brazil using quantitative models through Bayesian network approaches. The research was conducted using the Continental Surveillance and Information System (SivCont) database for Official Veterinary Services in Brazil, which refers to notified vesicular syndromes. The data on states, reported diseases, source of notification, disease confirmation, and timeliness (TL in days) of the delay by owners in notifying (TL.1) after a suspected case of the disease, and the response of Brazilian Veterinary Services after being notified (TL.2), were analysed. The collected data were analysed using Bayesian networks. It was observed that diseases with symptoms identical to FMD are the most notified events. TL.1 was long (mean of 18.96, CI: 18.33-19.59), and a low number of notifications was observed throughout the study period, which increases the chances of disseminating FMD in the population. Meanwhile, TL.2 suggests appropriate effectiveness of the Veterinary Services responding to suspected cases of FMD with interventions in less than 24 h (mean of 1, CI: 0.68-1.31). This study evaluated the performance of Brazilian Veterinary Services facing the report of vesicular diseases in the period 2004-2018. The results can help the states improve the surveillance system and the transition to the vaccination stop. Furthermore, the analytical method presented in the paper could serve as a model for other countries to evaluate the effectiveness of FMD surveillance systems.
Assuntos
Vírus da Febre Aftosa , Febre Aftosa , Animais , Teorema de Bayes , Brasil/epidemiologia , Surtos de Doenças/veterinária , Febre Aftosa/epidemiologia , Febre Aftosa/prevenção & controle , Saúde Global , Vacinação/veterináriaRESUMO
Animal health surveillance programmes should be reliable and informative to ensure their effective implementation. As such, the regular assessment of those aiming to demonstrate the absence of disease, as well as the ability to detect outbreaks on time, is of vital importance. Several criteria make it possible to assess the performance of surveillance systems, including timeliness, which represents the speed between steps in a surveillance system. Therefore, the objective of this study was to evaluate the variability in the timeliness, within and between states, of the surveillance programme of the Brazilian Veterinary Services (BVS) for foot-and-mouth disease (FMD), for the notification of vesicular disease. A total of 14 years (2004-2017) of data relating to vesicular syndromes from the Brazilian Continental Information and Surveillance System (SivCont) were included. A categorical variable was created with four classes to group the notified vesicular processes in the SivCont, according to two criteria, the similarity of the symptoms of the diseases reported with FMD and aetiology (viral, bacterial, fungal and non-infectious). The three timeliness values (TL-1, TL-2 and TL-3) related to different portions of the FMD surveillance system were analysed as a response in a generalized linear model in which the states of Brazil were the explanatory variables. The analyses were performed separately for each notification class (FMD, vesicular stomatitis, similar symptoms and similar non-infectious symptoms) and included comparisons within and between states. The study results provide an understanding and evaluation of the timeliness of the Brazilian FMD surveillance system, thereby providing a base of knowledge from which involved agents and decision-makers can evaluate BVS and reinforce surveillance measures in the states with poorer timeliness than permitted.