Frequency of leptospirosis in horses in Manaus and metropolitan region in Amazonas State, Brazil

Abstract

The occurrence of leptospirosis is significantly higher in the tropical climate than in temperate regions, especially in periods with high rainfall levels. In horses, leptospirosis can range from subclinical to asymptomatic but maintains an important role in the transmission of leptospirosis by eliminating the agent in the environment. Regarding horses, the Amazonas herd increased by 30% between 2004 and 2013. Thus, the study aimed to determine the serological prevalence of leptospirosis in horses in Manaus and metropolitan regions, in the State of Amazonas, Brazil as well as to assess the main serogroups involved in the infections of these animals. For this purpose, from August 2018 to July 2019, serum from 198 horses was evaluated through the microscopic agglutination test with a panel of 10 serogroups. As a result, 92 horses (44.46%) were found to be positive for one or more Leptospira serovars, with the highest prevalence of serogroups Icterohaemorrhagiae and Pyrogenes. Therefore, with the increase in the equine herd in the region and, consequently, greater interaction between breeders and animals, the identification of reagents to at least one serovar of Leptospira spp. signals the possible existence of reservoirs of pathogenic strains for other animals and man.

Seroepidemiology of leptospirosis in horses from Santarém, Pará

“…In a study performed in Bahia State, northeast Brazil by Gomes et al (17) also observed a higher prevalence of the serogroup Pyrogenes (24.0%), demonstrating the equal importance of this serogroup in serologic surveys of horses in different Brazilian regions. Moraes et al (11) , in Pará, and Sousa et al (12) , in Amazonas, also observed, as in this study, a high prevalence of the serogroup Pyrogenes in horses, which may suggest the maintenance of this serogroup in some domestic or wild animals of the Amazonic region. Abroad, the Pyrogenes serogroup has also been identified, with the highest seroprevalence in horses from Switzerland (18) .…”

“…Our results demonstrated that 58 horses (65.9%) were seropositive, indicating that these horses had direct or indirect contact with Leptospira spp. Research conducted in the last decade in Brazil showed considerable variation regarding the leptospirosis seroprevalence in horses (9,12) . The observed frequency in this study (65.9%) was similar to that found in studies performed in the State of Paraná (Brazil), which reported a 66.88% seropositivity (16) .…”

“…northern Brazil the seroprevalence of other serovars such as Australis, Autumnalis, and Pyrogenes, in addition to Bratislava and Icterohaemorrhagiae, were observed (10)(11)(12) . However, in northern Brazil, there are fewer studies regarding the current prevalence of leptospirosis in horses.…”

Soroepidemiologia de leptospirose em equinos da região de Santarém, Pará

“…Em equinos, a leptospirose é causada principalmente pelos sorovares Bratislava e Icterohaemorrhagiae (8) , porém a prevalência pode variar de acordo com a região (9) . Nesse sentido, em alguns estudos realizados no norte do Brasil foi observado a soroprevalência de outros sorovares como Australis, Autumnalis e Pyrogenes, além de Bratislava e Icterohaemorrhagiae (10)(11)(12) . No entanto, no norte do Brasil, há poucos estudos sobre a atual prevalência de leptospirose em equinos.…”

Occurrence of Leptospira spp. and factors associated with the infection in horses from a military contingent in the Rio Grande do Sul State, Brazil

“…In equine species, this infection has been neglected. But the recognition that the disease can cause major economic losses, mainly because of abortion and blindness in animals of high zootechnical value, has attracted greater attention to this disease (Adler, 2015;Castro et al, 2011;Sousa et al, 2020).…”