Trop Med Infect Dis
August 2024
In 2018, an outbreak of human rabies caused by the hematophagous bat 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.
View Article and Find Full Text PDFRabies is a contagious viral disease that can be easily transmitted by the saliva and brain/nervous system tissues of the infected animals, causing severe and fatal encephalitis in both animals and humans. Vaccination campaigns are crucial to combat and prevent rabies's spread in dogs and humans. The Modified Fuenzalida & Palicios vaccines have been widely used since the 70s and have proven effective in producing a solid serological response.
View Article and Find Full Text PDFRabies virus is recognized as one of the most fatal zoonotic agents affecting all mammals. Wild boars (Sus scrofa), classified as a large-size exotic invasive species in Brazil with nationwide hunting permitted, may serve as an extra blood source for the common vampire bat (Desmodus rotundus). Our aim was to document wild boar exposure to vampire bats to determine the seroprevalence of rabies virus antibodies in wild boars and to determine the immune status of hunters in southern and central-western Brazilian regions.
View Article and Find Full Text PDFWe evaluated the presence of antibodies for rabies virus in 177 serum samples from 125 wild lowland tapirs (Tapirus terrestris) from three different Brazilian biomes. The rapid fluorescent focus inhibition test was performed. No antibody titers suggesting the circulation of the rabies virus in tapir habitat were detected.
View Article and Find Full Text PDFThe direct rapid immunohistochemical test (dRIT) has been recommended for laboratorial diagnosis of rabies, especially in developing countries. The absence of commercial primary antibodies, however, still represents a major limitation to its wider use in testing. We describe here the development of a biotinylated polyclonal antibody against Rabies lyssavirus (RABV) ribonucleoprotein (RNP) and its use as a primary reagent in dRIT.
View Article and Find Full Text PDFHere, we compared the growth kinetics, cell-to-cell spread, and virus internalization kinetics in N2a cells of RABV variants isolated from vampire bats (V-3), domestic dogs (V-2) and marmosets (V-M) as well as the clinical symptoms and mortality caused by these variants. The replication rate of V-3 was significantly higher than those of V-2 and V-M. However, the uptake and spread of these RABV variants into N2a cells were inversely proportional.
View Article and Find Full Text PDFBackground: Rabies is an incurable neglected zoonosis with worldwide distribution characterized as a lethal progressive acute encephalitis caused by a lyssavirus. Animal venoms and secretions have long been studied as new bioactive molecular sources, presenting a wide spectrum of biological effects, including new antiviral agents. Bufotenine, for instance, is an alkaloid isolated from the skin secretion of the anuran Rhinella jimi that inhibits cellular penetration by the rabies virus.
View Article and Find Full Text PDFIntroduction: In Brazil, various isolates of rabies virus (RABV) show antigenic profiles distinct from those established by the reduced panel of eight monoclonal antibodies (MAbs) determined by the Centers for Disease Control and Prevention (CDC), utilized for the antigenic characterization of RABV in the Americas. The objective of this study was to produce MAbs from RABV isolates from insectivorous bats with an antigenic profile incompatible with the pre-established one.
Methodology: An isolate of RABV from the species Eptesicus furinalis that showed an antigenic profile incompatible with the panel utilized was selected.
Objective: To evaluate the humoral immune response to the pre-exposure schedule of human rabies vaccination through intradermal and intramuscular routes, as well as the need for serological monitoring.
Methods: A randomized and controlled intervention study was carried out in São Paulo, Southeastern Brazil, from 2004-2005. There were 149 volunteers, of which 127 completed the vaccination schedule (65 intradermal and 62 intramuscular) and underwent humoral immune response evaluation at ten, 90 and 180 days post-vaccination.
The laboratory tests recommended by the World Health Organization for detection of rabies virus and evaluation of specific antibodies are performed with fluorescent antibodies against the virus, the ribonucleoproteins (RNPs), or by monoclonal antibodies. In this study, we purified the rabies virus RNPs for the production of a conjugate presenting sensibility and specificity compatible with commercial reagents. The method employed for the purification of RNPs was ultracentrifugation in cesium chloride gradient, the obtained product being used for immunizing rabbits, from which the hyperimmune sera were collected.
View Article and Find Full Text PDFThe immunogenicity and safety of a new human rabies vaccine, produced in Vero cells by a process that does not require supplementation with human or animal derived components in production, were assessed. Thus, the objective is to produce a safer vaccine at a lower cost. A total of 296 volunteers was divided into two groups: Group 1, which received the study vaccine, and Group 2, which received the Vero cells vaccine produced by Sanofi Pasteur.
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