Epidemiological surveillance of capybaras and ticks on warning area for Brazilian spotted fever

Abstract

Aim:The vulnerability of tropical developing countries to the emerging disease constitutes a critical phenomenon in which the invasion of wild niches by human hosts, contributes to expansion of zoonotic diseases, such as the Brazilian spotted fever (BSF). This study performed a diagnosis of species occurrence of their hosts (Hydrochoerus hydrochaeris) and vectors (Amblyomma sculptum and Amblyomma dubitatum) on the warning area for this reemerging disease in Brazil.Materials and Methods:The study was conducted in a warning area for BSF in the city of Americana, São Paulo state. The occurrence of capybaras was registered by use of binoculars and GPS equipment and 24 acarological researches were performed through 180 CO2 traps. Samples of adult ticks were dissected for salivary glands removal, DNA extraction, and evaluation by polymerase chain reaction (PCR) being tested by initial gltA-PCR, ompA-PCR, and Rickettsia bellii-specific PCR, with the positive samples subjected to sequencing.Results:Eleven clusters of capybaras (total of 71 individuals), were observed along the riparian of Ribeirão Quilombo and 7,114 specimens of A. sculptum and 7,198 specimens of A. dubitatum were collected in this same area. About 568 samples of adult ticks were dissected for salivary glands removal, DNA extraction and evaluation by gltA-PCR, with results of 1.94% (11/568) of positive samples. Results for the initial gltA-PCR indicated none positive sample to Rickettsia species into A. sculptum and 11 positive samples to A. dubitatum. These samples were negative to the ompA-PCR and positive to the Rickettsia bellii-specific PCR protocol and subjected to DNA sequencing, whose result indicated 100% similarity to Rickettsia bellii. The distribution of tick species A. sculptum and A. dubitatum was configured regarding to the biotic potential of the riparian areas, measuring the risks for BSF in peri-urban areas of Americana.Conclusion:These results confirmed a status of epidemiological warning with a strong association of the amplifiers hosts of Rickettsia and tick vectors for the transmission of BSF to humans in this region.

Febre Maculosa No Brasil: Situação Epidemiológica Atual E a Distribuição Geográfica De Carrapatos Em Cenários De Mudanças Climáticas

“…Amblyomma cajennense foi por muitos anos considerado uma única espécie com ampla distribuição nas Américas e relacionado à transmissão da febre maculosa na região Sudeste do Brasil (Labruna, 2009 Outras espécies já foram assinaladas como importantes para a manutenção do ciclo enzoótico de riquétsias em áreas endêmicas da FM como A. dubitatum (Almeida et al, 2011;Brites-Neto et al, 2015), espécie parasita de capivaras e Rhipicephalus sanguineus conhecido como carrapato do cão (Gehrke et al, 2009;Cunha et al, 2009;de Almeida et al, 2013). Popularmente conhecido por "carrapato-estrela", "rodoleiro", "micuim" ou "vermelhinho" essa espécie é parasita preferencial de cavalos, antas, capivaras e porcos (Labruna, 2009) e a presença desses hospedeiros em ambiente é associada a infestações consideráveis por este vetor.…”

“…(Szabo et al, 2013;Barbieri et al, 2014;Vizzoni et al, 2016;Krawczak et al, 2016c). (Souza et al 2006;Souza et al, 2008;Almeida et al, 2011;Brites-Neto et al, 2015). Os cavalos podem atuar também como hospedeiros de A. sculptum em áreas endêmicas (Del Guercio et al, 1997;Labruna et al, 2001;Freitas et al, 2010;Batista et al, 2010;Meira et al, 2013).…”

“…Amblyomma sculptum e capivaras são responsáveis pela manutenção da FM causada pela R. rickettsii na região Sul e Sudeste do Brasil (Labruna, 2009;Szabo et al, 2013;Nasser et al, 2015;Souza et al, 2015;Brites-Neto et al, 2015).…”

Bats used as hosts by Amblyomma sculptum (Acari: Ixodidae) in Northeastern Brazil and its implications on tick-borne diseases

“…Horses and capybaras are the primary hosts for these ticks (Sangioni et al 2005, Labruna 2009). However, A. sculptum also feeds on many domestic and wild terrestrial mammals (Garcia et al 2013, Brites-Neto et al 2015.…”

>b<Study on the perspective of population control of capybaras (>i<Hydrochoerus hydrochaeris>/i<) by reversible immunocontraceptive method>/b<

“…: "febre maculosa"). Capybara are considered an amplifying host for this emerging vector-borne zoonosis caused by the potentially deadly bacterium Rickettsia rickettsii, which is spread by ticks of the genera Amblyomma ssp (Brites- Neto, Brasil, & Roncato Duarte, 2015;Fortes et al, 2011;…”