Microorganisms in the ticks Amblyomma dissimile Koch 1844 and Amblyomma rotundatum Koch 1844 collected from snakes in Brazil.

Knowledge about ticks (Acari) and screening of ticks parasitizing various hosts are necessary to understand the epidemiology of tick-borne pathogens. The objective of this study was to investigate tick infestations on snakes (Reptilia: Squamata: Serpentes) arriving at the serpentarium at the Institute Vital Brazil, Rio de Janeiro. Some of the identified ticks were individually tested for the presence of bacteria of the genera Rickettsia (Rickettsiales: Rickettsiaceae), Borrelia (Spirochaetales: Spirochaetaceae), Coxiella (Legionellales: Coxiellaceae), Bartonella (Rhizobiales: Bartonellaceae), Ehrlichia (Rickettsiales: Anaplasmataceae), Anaplasma (Rickettsiales: Anaplasmataceae), and Apicomplexa protozoa of the genera Babesia (Piroplasmida: Babesiidae) and Hepatozoon (Eucoccidiorida: Hepatozoidae). A total of 115 hard ticks (Ixodida: Ixodidae) were collected from 17 host individuals obtained from four Brazilian states. Two species of tick were identified: Amblyomma dissimile Koch 1844 (four larvae, 16 nymphs, 40 adults), and Amblyomma rotundatum Koch 1844 (12 nymphs, 43 adults). Rickettsia bellii was found in A. rotundatum and A. dissimile ticks and Rickettsia sp. strain Colombianensi, Anaplasma-like and Hepatozoon sp. in A. dissimile ticks. Among the tested ticks, no DNA of Borrelia, Bartonella, Coxiella or Babesia was found. The present findings extend the geographic range of Rickettsia sp. strain Colombianensi in Brazil and provide novel tick-host associations.

Hantavirus pulmonary syndrome in a highly endemic area of Brazil.

Hantavirus pulmonary syndrome (HPS) is the most frequently reported fatal rodent-borne disease in Brazil, with the majority of cases occurring in Santa Catarina. We analysed the clinical, laboratory and epidemiological data of the 251 confirmed cases of HPS in Santa Catarina in 1999-2011. The number of cases ranged from 10 to 47 per year, with the highest incidences in 2004-2006. Gastrointestinal tract manifestations were found in >60% of the cases, potentially confounding diagnosis and leading to inappropriate therapy. Dyspnoea, acute respiratory failure, renal failure, increased serum creatinine and urea levels, increased haematocrits and the presence of pulmonary interstitial infiltrate were significantly more common in HPS patients who died. In addition, we demonstrated that the six cases from the midwest region of the state were associated with Juquitiba virus genotype. The case-fatality rate in this region, 19·2%, was lower than that recorded for other mesoregions. In the multivariate analysis increase of serum creatinine and urea was associated with death by HPS. Our findings help elucidate the epidemiology of HPS in Brazil, where mast seeding of bamboo can trigger rodent population eruptions and subsequent human HPS outbreaks. We also emphasize the need for molecular confirmation of the hantavirus genotype of human cases for a better understanding of the mortality-related factors associated with HPS cases in Brazil.

A cluster of Rickettsia rickettsii infection at an animal shelter in an urban area of Brazil.

Rickettsia rickettsii infection is being increasingly recognized as an important cause of fatal acute illness in Brazil, where this tick-borne disease is designated Brazilian spotted fever (BSF). In this study we report five fatal cases of BSF in employees of an animal shelter in an urban area in the municipality of Rio de Janeiro in southeast Brazil after a natural disaster on 11 January 2011. Four of the cases occurred from 27 January to 11 April 2011, while the fifth fatal case was identified in April 2012. Three cases were confirmed by molecular analysis and two by epidemiological linkage. An investigation of BSF was performed in the animal shelter, and blood samples were collected from 115 employees and 117 randomly selected dogs. The presence of high levels (1024-4096) of antibodies against spotted fever group rickettsiae was found in three (2·6%) employees and 114 (97·5%) dogs. These findings emphasize the need to consider BSF as a possible cause of undifferentiated febrile illness, especially dengue and leptospirosis, in patients occupationally exposed to dogs heavily infested by ticks, mainly working at kennels and animal shelters that have inadequate space for the animals housed and frequently providing an environment conducive to exposure to pathogens such as R. rickettsii.

Regional variations and time trends of hantavirus pulmonary syndrome in Brazil.

Hantavirus pulmonary syndrome (HPS) is a zoonosis and a public health concern in the Americas due to its high fatality rate. Since the first cases were identified in USA in 1993, HPS has been observed over a wide area of the American continents. Over 1600 HPS cases have been confirmed in Brazil since 1993, and different genotypes of hantavirus have been identified in several biomes in this country of continental dimensions. We performed a retrospective study of data from 2001 to 2011 that encompassed all notified cases of HPS in the National Disease Notification System (SINAN) of Brazil to determine the regional differences and temporal trends of the disease. During the study period, 1486 cases were reported, and analyses of the temporal trends of the disease revealed that the number of cases in Brazil increased over this period (P < 0·01). The frequency distributions of the cases stratified by region revealed different patterns of seasonality; however, these patterns were not statistically significant with the exception of the South region (P < 0·05). We found regional differences in the occurrence of the disease throughout the year and a trend towards an increasing number of cases. These findings reinforce the necessity of adjusting surveillance tools and control policies to respond effectively to this public health problem.