A cluster ofRickettsia rickettsiiinfection at an animal shelter in an urban area of Brazil

Abstract

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.

Seroprevalence of Rickettsia rickettsii and Rickettsia parkeri in dogs during a Brazilian Spotted Fever outbreak in the State of Rio de Janeiro

“…(Gasser et al, 2001;Raoult and Parola, 2007), the titration of the samples was done. The titers obtained in this study are higher than others showed in studies previously done in areas with rickettsia circulation or in BSF outbreak areas (Horta et al, 2007;Pinter et al, 2008;Gazeta et al, 2009;Cunha et al, 2014;Rozental et al, 2015;Cordeiro et al, 2015). Of the dogs included in this study, 138/253 (54.55%) were classified as crossbreeds.…”

“…Data on SFGR dispersion are located in the southern region of Rio de Janeiro State (RJ) (Gazeta et al, 2009;Cunha et al, 2014;Rozental et al, 2015;Cordeiro et al, 2015), while other regions do not have any studies, despite reports of BSF-related deaths. In 2014, there were reports of several confirmed cases and human deaths due to the BSF in the cities of Natividade, Porciuncula and Varre-Sai, as well as various suspected cases.…”

Spotted Fever: Epidemiology and Vector-Rickettsia-Host Relationship in Rio de Janeiro State

“…However, the process of SF urbanization does not seem to be common throughout Brazil (Barros-Silva et al, 2014), but it is evident in the southeastern part of the country (Nasser et al, 2015; Souza et al, 2015). Some studies have reinforced the importance of areas experiencing urban expansion and deforestation, or places where work is done with mammals in confinement, and other environmental determinants in the epidemiological dynamics of SF (Gazeta et al, 2009; Labruna, 2009; Ogrzewalska et al, 2011; Moura-Martiniano et al, 2014; Rozental et al, 2014; Nasser et al, 2015). In fact, regions of higher density seem more conducive to the emergence of cases in southeastern Brazil, even in rural areas (Ribeiro et al, 2013).…”

“…In general, within the study area the disease is first diagnosed as leptospirosis or dengue, and when the case progresses to death, SF is suspected (Lamas et al, 2008; Moliterno, 2009; Monteiro et al, 2014; Rozental et al, 2014). …”

Antibodies for Rickettsia spp. in patients with negative serology for dengue virus, leptospirosis, and meningococcal disease in municipalities of São Paulo State, Brazil

“…In addition, a potential risk of transmission of BSF or other rickettsial infectionsviaparasitized dogs cannot be ruled out. In this respect, there is a recent report regarding a Rocky Mountain spotted fever outbreak among employees of an animal shelter, where the authors, despite the inability to confirm the involved tick species, point out the risk of infection to humans when in close contact with dogs (22) .…”