Novel Spotted Fever Group Rickettsiosis, Brazil

Abstract

We report a clinical case of spotted fever group rickettsiosis acquired in São Paulo, Brazil. Definitive diagnosis was supported by seroconversion between acute-phase and convalescent-phase serum samples. Molecular analysis of skin samples indicated the agent was a novel spotted fever group strain closely related to Rickettsia africae, R. parkeri, and R. sibirica.

Spotted fever group Rickettsia infecting ticks (Acari: Ixodidae) in the state of Santa Catarina, Brazil

“…The two cases of human spotted fever caused by R. parkeri strain Atlantic rainforest in SP (Spolidorio et al 2010) and BA (Silva et al 2011) were clinically similar to the dozens of spotted fever cases that have been reported in SC ). These cases were characterised by milder haemorrhagic manifestations and no lethality.…”

“…Herein, we considered the Atlantic rainforest strain to belong to the species R. parkeri based on the gene sequence-based criteria recently proposed for identification of new Rickettsia isolates (Fournier et al 2003), as discussed by Spolidorio et al (2010). However, we are aware that the species definition for Rickettsia remains a controversial issue, without a major consensus among rickettsiologists (Walker & Ismail 2008, Fournier & Raoult 2009, Goddard 2009).…”

“…This strain is considered to be pathogenic for humans and it was recently found to be the causative agent of two cases of spotted fever in humans in Brazil, one in SP (Spolidorio et al 2010) and another in the state of Bahia (BA) (Silva et al 2011). In addition, in SP, Sabatini et al (2010) reported that the Atlantic rainforest strain was present in 13.6% and 1.9% of A. ovale and R. sanguineus ticks, respectively, collected from dogs, and in 8.8% of A. ovale ticks collected from vegetation.…”

Detecção de proteínas imunorreativas de Rickettsia sp. cepa Mata Atlântica

“…Apenas em 2004 foi classificada como responsável por causar Febre Maculosa em humanos, sendo considerada agente de uma leve ou moderada doença em muitos países do continente Americano (Paddock et al 2004). Uma nova riquetsiose humana foi descrita como causadora de FMB no Estado de São Paulo, apresentando um quadro clínico semelhante em infecções causadas por R. parkeri (Spolidorio et al 2010). Este novo agente riquetsial foi denominado de Rickettsia sp.…”

“…Este novo agente riquetsial foi denominado de Rickettsia sp. cepa Mata Atlântica devido a sua similaridade filogenética com as espécies R. parkeri, Rickettsia africae e Rickettsia sibirica (Spolidorio et al 2010). Além do Brasil, este novo agente foi identificado em outros países da América Latina, como Colômbia e Argentina, e na América Central (Lopes et al 2016, Parola et al 2013, Londoño et al 2014, Monje et al 2015.…”