Spotted fever in Brazil: a seroepidemiological study and description of clinical cases in an endemic area in the state of São Paulo.

Lemos, Elba Regina Sampaio de; Alvarenga, F B; Cintra, Maria Letícia; Ramos, Marisa; Paddock, Christopher D.; Ferebee, Tara; Zaki, Sherif R.; Ferreira, Fernanda Cambraia; Ravagnani, R C; Machado, Raúl; Guimarães, Maria Angélica Arpon Marandino; Coura, José Rodrigues

doi:10.4269/ajtmh.2001.65.329

Cited by 78 publications

(94 citation statements)

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“…41 confirmed BSF cases of have been reported since 1985 (CVE 2006). The clinical severity (including high lethality), serological analyses, and isolation of Rickettsia from clinical samples of these cases were compatible with R. rickettsii (Lemos et al 2001, Angerami et al 2006. The presence of R. bellii and R. parkeri (strain Cooperi) was reported infecting the capybara tick Amblyomma dubitatum ), whereas R. felis was reported infecting fleas Ctenocephalides felis felis .…”

Section: Methodsmentioning

confidence: 87%

Rickettsia infection in five areas of the state of São Paulo, Brazil

Horta

Labruna

Pintér

et al. 2007

Mem. Inst. Oswaldo Cruz

181

129

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This study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of São Paulo. Eight flea species (Adoratopsylla antiquorum antiquorum, Ctenocephalides felis felis, Polygenis atopus, Polygenis rimatus, Polygenis roberti roberti, Polygenis tripus, Rhopalopsyllus lugubris, and Rhopalopsyllus lutzi lutzi), and five tick species (Amblyomma aureolatum, Amblyomma cajennense, Amblyomma dubitatum, Ixodes loricatus, and Rhipicephalus sanguineus) were collected from dogs, cats, and opossums. Rickettsia felis was the only rickettsia found infecting fleas, whereas Rickettsia bellii was the only agent infecting ticks, but no animal or human blood was shown to contain rickettsial DNA. Testing animal and human sera by indirect immunofluorescence assay against four rickettsia antigens (R. rickettsii, R. parkeri, R. felis, and R. bellii), some opossum, dog, horse, and human sera reacted to R. rickettsii with titers at least four-fold higher than to the other three rickettsial antigens. These sera were considered to have a predominant antibody response to R. rickettsii. Using the same criteria, opossum, dog, and horse sera showed predominant antibody response to R. parkeri or a very closely related genotype. Our serological results suggest that both R. rickettsii and R. parkeri infected animals and/or humans in the studied areas.Key words: Rickettsia -spotted fever -fleas -ticks -opossum -domestic animals Rickettsiae are obligate intracellular bacteria that have been classically divided into two groups: the typhus group (TG), composed of Rickettsia prowazekii and Rickettsia typhi, which are associated with lice and fleas, respectively; and the spotted fever group (SFG), which includes more than 20 valid species, mostly associated with ticks (e.g., Rickettsia rickettsii, Rickettsia parkeri), and at least one species associated with fleas (Rickettsia felis). Other species, such as Rickettsia bellii and Rickettsia canadensis, both associated with ticks, have been considered a distinct group sharing antigenic, genetic and ecological characters with both TG and SFG rickettsiae (Parola et al. 2005b). Since all SFG Rickettsia share common outer membrane antigens, conventional serological assays employing a single Rickettsia antigen (e.g., R. rickettsii) allow detecting a SFG infection, but they do not identify the Rickettsia species responsible for the infection, even in the presence of high titers (La Scola & Raoult 1997). For a more specific serological diagnosis, it is recommended techniques such as testing serum against all known Rickettsia species present in a given area, or serum cross-absorption tests (La Scola & Raoult 1997, Parola et al. 2005b).For many years, SFG rickettsiosis in the Americas was thought to be caused only by R. rickettsii, transmitted by ticks (Weiss & Moulder 1984). This rickettsia has been reported in several countries from North, Central, and South America causing an acute, highly lethal febrile disease receiving different names according to the country...

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Section: Methodsmentioning

confidence: 87%

Rickettsia infection in five areas of the state of São Paulo, Brazil

Horta

Labruna

Pintér

et al. 2007

Mem. Inst. Oswaldo Cruz

181

129

View full text Add to dashboard Cite

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“…As compared with other Brazilian seroprevalence studies the rate found here for R. rickettsii was low. Lemos et al (1994Lemos et al ( , 2001), Del Guercio et al (1997), and Galvão et al (2002) found respectively 7.14, 4.2, 5.3, and 10.1% seroprevalence rates in different serosurveys. Despite this low seroprevalence rate, spotted fever group rickettsioses have been increasing in the studied region with an incidence of over 0.5/100,000 inhabitants-year (Costa 2004) compatible with the ongoing epidemic expansion recently reported from some Brazilian southeast regions (Rozental et al 2002, Galvão et al 2003.…”

Section: Discussionmentioning

confidence: 99%

Antibodies to Rickettsia rickettsii, Rickettsia typhi, Coxiella burnetii, Bartonella henselae, Bartonella quintana, and Ehrlichia chaffeensis among healthy population in Minas Gerais, Brazil

Costa

Brigatte

Greco

2005

Mem. Inst. Oswaldo Cruz

100

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Rickettsial diseases except those belonging to spotted fever group rickettsioses are poorly studied in South America particularly in Brazil where few epidemiological reports have been published. We describe a serosurvey for Rickettsia rickettsii, R. typhi, Coxiella burnetii, Bartonella henselae, B. quintana, and Ehrlichia chaffeensis in 437 healthy people from a Brazilian rural community. The serum samples were tested by indirected micro-immunoflourescence technique and a cutoff titer of 1:64 was used. The seroprevalence rates for R. rickettsii, R. typhi, C. burnetii, B. henselae, B. quintana, and E. chaffeensis were respectively 1.6% (7 samples (WHO 1993, Rozental et al. 2002, Walker 2004a. Until recently the rickettsiales order comprised the genus Rickettsia, Coxiella, Bartonella, Orientia, Anaplasma, and Ehrlichia (Raoult & Roux 1997) and despite of the resulting withdraw of some of them from this order especially due to 16S rRNA studies, they all can be functionally considered rickettsial agents (Raoult & Roux 1997, Walker 2004b.Most of the available publications of Brazilian rickettsial infections have focused on spotted fever group rickettsioses especially R. rickettsii infections (Lemos et al. 1994, Del Guercio et al. 1997, Rozental et al. 2002, Galvão et al. 2003. This issue has been extensively reviewed recently by Galvão (2004). Despite of the fact that new rickettsial agents have been described more recently in Brazil (Oliveira et al. 2002), the whole scenario of rickettsial infections still have black holes reinforcing the nonexistence concept for such infections in this part of the world.The Piau county as well as the southern part of the state of Minas Gerais had been considered free of any rickettsial diseases until 1994 when a family cluster of Brazilian spotted fever was reported (Hallack et al. 1996). Thereafter reports of Brazilian spotted fever have been Given these above mentioned facts and the much-appropriated local ecologic conditions for rickettsial infections we choose this particular region for studying the seroprevalence rates for R. typhi, C. burnetii, B. henselae, B. quintana, and E. chaffeensis as well as R. rickettsii infections among healthy individuals from a Brazilian rural community. MATERIALS AND METHODSSerum samples from 437 healthy individuals of both sexes aged from 5 to 92 years old, living in the county of Piau, state of Minas Gerais, Brazil were tested for the presence of R. rickettsii, R. typhi, C. burnetii phase I and phase II, B. henselae, B. quintana, and E. chaffeensis IgG and IgM antibodies. This county (Fig. 1), located at latitude 21º30'34''S and longitude 43º19'25''W, has 3008 inhabitants, 58% of them living in the small village and the remainders scattered throughout the county, mostly in small farms. The local economics is somehow linked to cattle farming and the entire population has continuous contact with several domestic animals. Tick attack history is widespread affecting roughly 100% of the population. From March to April 2001, health officials offe...

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“…Therefore, these cases cannot be considered confirmed cases of R. rickettsii infection. However, the severe clini- cal signs, high fatality rate and epidemiological data suggest that most of these cases were caused by R. rickettsii (Lemos et al 2001, Angerami et al 2006a. In fact, a few of these infections were investigated more thoroughly using molecular methods and were confirmed to be caused by R. rickettsii (Nascimento et al 2005, Rozental et al 2006, Lamas et al 2008).…”

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confidence: 99%