Pre-Exposure Prophylaxis to Prevent Hematophagous Bat-Mediated Rabies Outbreaks in Remote Amazon Communities: Lessons from a Pilot for Public Health Policy.

In 2018, an outbreak of human rabies caused by the hematophagous bat Desmodus rotundus hit the Brazilian Amazon Basin community of Melgaço, Brazil, resulting in the death of 10 people, 9 of them children. The incidence of rabies has been on the rise among populations in conditions of vulnerability in this ecosystem due to human expansion into sylvatic environments and limited access to public health services. To address this issue, in September 2019, a collaborative effort from national, local, and international institutions promoted and executed a pilot for pre-exposure prophylaxis of a population in high-risk areas for hematophagous bat-mediated rabies. This measure is usually only implemented in response to outbreaks. The pilot was conducted in Portel, in a nearby location to the previous outbreak, with the use of fluvial transportation, and 2987 individuals in 411 dwellings were successfully vaccinated. It established a methodology for pre-exposure prophylaxis for populations in conditions of vulnerability, identifying logistics and costs, as well as characterizing the target riverine population regarding risk factors associated with bites by hematophagous bats. This approach offers a proactive measure to prevent future outbreaks and provides valuable insights into how to address the issue of rabies in remote and difficult-to-reach areas.

Establishing an anesthetic protocol for refinement of intracerebral inoculation procedure

Mouse inoculation test (MIT) is a technique widely used for rabies diagnosis and must be liable to refinement due to animal welfare. The present study aims to compare five different anesthetic associations to stablish a protocol to improve the MIT procedure suitable for animal welfare and safe for a routine of viral isolation in newly weaned mice (3 weeks of age). 80 Swiss-Webster mice (Mus musculus) - 40 females and 40 males, 3-week-old, weight ranging from 11 to 14 grams ­ were used to conduct all procedures. Five anesthetic associations were tested: KX (Ketamine 100 mg/kg and Xylazine 10 mg/kg), KXA (Ketamine 80 mg/kg, Xylazine 5 mg/kg, and Acepromazine 1 mg/kg), KXT (Ketamine 80 mg/kg, Xylazine 5 mg/kg, and Tramadol 5 mg/kg), KXAT (Ketamine 100 mg/kg, Xylazine 10 mg/kg, Acepromazine 2 mg/kg and Tramadol 5 mg/kg) and ATI (Acepromazine 1 mg/kg + Tramadol 5 mg/kg + Isoflurane 5% - 0.5 L/min for induction and 2.5% - 0.5L/min for maintenance). Injectable anesthesia was administered intraperitoneally. We monitored the respiratory rate and body temperature. Response to anesthesia was evaluated according to the induction, surgical anesthesia, and recovery periods. The KXAT and ATI protocols induced surgical anesthesia, with the ATI protocol being the most appropriate and safe to perform the MIT procedure with 100% efficiency, absence of mortality, and rapid recovery of respiratory rate and temperature in the period after the procedure.

Reservatórios silvestres do vírus da raiva: um desafio para a saúde pública / Wildlife reservoirs of rabies virus: a new challenge to a public health

Estima-se que 55.000 óbitos humanos sejam causados pela raiva transmitida pelo cão, anualmente, em especial na Ásia e África. Na América Latina, onde a raiva canina era endêmica até 1980, houve, recentemente, uma redução do número de casos em cães e, conseqüentemente, em humanos. Com o desenvolvimento do Plano de Ação para Eliminação da Raiva Urbana, a raiva em animais silvestres assumiu maior importância, especialmente porque nos anos 2004-2005 o morcego hematófago (Desmodus rotundus) passou a ser o principal transmissor da raiva humana no continente (68%). Além das três espécies de morcegos hematófagas nas quais há relatos de isolamento do vírus da raiva, 33 outras espécies de morcegos também já foram infectadas e identificadas com o mesmo vírus. Juntamente com os morcegos (Ordem Chiroptera), os canídeos (Ordem Carnivora) são considerados os principais reservatórios silvestres do vírus da raiva. No Nordeste do Brasil a doença tem sido cada vez mais freqüente em Cerdocyon thous (cachorro do mato) e há um outro ciclo epidemiológico da raiva em Callithrix jacchus (sagüi do tufo branco), espécie em que a distribuição da doença é desconhecida. Os autores descrevem características da doença em quirópteros e carnívoros, estratégias de controle e ressaltam a importância dos estudos antigênicos e genéticos como instrumento da vigilância epidemiológica.