Seroepidemiological monitoring in sentinel animals and vectors as part of arbovirus surveillance in the state of Mato Grosso do Sul, Brazil

Paulo Mira Batista,Jannifer Oliveira Chiang,Renato Andreotti,Pedro Fernando da Costa Vasconcelos,Milene Silveira Ferreira

doi:10.1590/s0037-86822012000200006

Abstract

From February-September 2010, seroepidemiological surveys were conducted on non-human primates and transmitter vector capture was used to investigate the possible circulation of arboviruses in the municipalities of Bonito, Campo Grande, and Jardim, State of Mato Grosso do Sul, Brazil. A total of 65 primates from the wild and captivity were used, and potential vectors were captured using Castro and dip nets. Serum samples were tested at the Instituto Evandro Chagas, State of Pará, using the hemagglutination inhibition test to detect total antibodies against 19 different arboviruses. Virus isolation was attempted from serum samples and arthropod suspensions using newborn mice and the C6/36 cell line clone. In addition, identification of the vector species was conducted. From the 19 serum samples from Campo Grande, 1 sample had a 1:20 titer for Flavivirus. From the 35 samples collected in Bonito, 17 samples had antibodies to arboviruses, 4 (11.4%) were positive for Alphavirus, and 5 (14.2%) were positive for Flavivirus. Monotypic reactions were observed for the Mayaro (n = 10) and Oropouche (n = 5) viruses, and 6 (17.1%) samples had titers for >1 virus. We captured 120 Culicidae individuals that were potential arbovirus transmitters in Jardim; however, all the samples were negative for the viruses. Mato Grosso do Sul has a variety of vertebrate hosts and transmission vectors, thereby providing ideal conditions for the emergence or reemergence of arboviruses, including some pathogenic to human beings.

Highlights

From February-September 2010, seroepidemiological surveys were conducted on non-human primates and transmitter vector capture was used to investigate the possible circulation of arboviruses in the municipalities of Bonito, Campo Grande, and Jardim, State of Mato Grosso do Sul, Brazil
The 11 serum samples collected from non-human primates captured in the town of Jardim and tested using the hemagglutination inhibition (HI) test were negative for the virus
From the 35 serum samples collected in Bonito, 17 (48.5%) showed evidence of antibodies for arboviruses, with 4 (11.4%) positive for Alphavirus and 5 (14.2%) positive for Flavivirus

Summary

INTRODUCTION

Arboviruses are almost completely maintained in the natural environment; people who have contact with enzootic foci are most at risk of acquiring infections that represent a public health problem[1]. Studies on arboviruses involve virology, serology, entomology, ecology, and zoology[3] Because they are usually diurnal arboreal species, non-human primates are more often infected by an arbovirus than other terrestrial animals; most of them have low hemagglutination inhibition antibody titers[4]. Serological studies on free-living or captive animals can determine antibody seropositivity rates, which often can lead to an understanding of virus circulation dynamics and host susceptibility; Batista PM et al - Arbovirus monitoring in Mato Grosso do Sul, Brazil susceptibility may be speculated upon even if the agent TABLE 1 - Distribution of the species and sex of free-ranging and captive non-human has not been isolated[4].

METHODS

Ethical considerations

RESULTS

DISCUSSION