Outbreak of vampire bat biting in a Venezuelan village

An outbreak of 154 cases of vampire bat biting in a four-month period in the gold mine of Payapal, a Venezuelan village, is reported. All patients were bitten during the night and the most bites were on their toes. No complication attributed to the bite was reported. Diagnoses of rabies virus made by means of immunofluorescence were negative. A possible reason for this outbreak may been the development of mining areas, with the inhabitants providing an alternative food source for the bats.

Descriptive ecology of bat flies (Diptera: Hippoboscoidea) associated with vampire bats (Chiroptera: Phyllostomidae) in the cerrado of Central Brazil

We studied the ectoparasitic bat flies of three phyllostomid vampire bat species. Bats were collected monthly from April 2004-March 2005 in caves within the Cafuringa Environmental Protection Area in the Federal District of Brazil. A total of 1,259 specimens from six species in the Streblidae family were collected from 332 bats. High host affinity from the sampled bat fly species and high prevalence of bat flies confirms the primary fly-host associations (Strebla wiedemanni, Trichobius parasiticus and Trichobius furmani with Desmodus, Trichobius diaemi and Strebla diaemi with Diaemus and T. furmani with Diphylla). Male flies outnumbered females in several associations. Some of the observed associations (e.g., Strebla mirabilis with Desmodus and S. mirabilis, Trichobius uniformis and S. wiedemanni with Diphylla) were inconclusive and the causes of the associations were unclear. There are several explanations for these associations, including (i) accidental contamination during sampling, (ii) simultaneous capture of several host species in the same net or (iii) genuine, but rare, ecological associations. Although various species of vampire bats share roosts, have similar feeding habits and are close phylogenetic relatives, they generally do not share ectoparasitic streblid bat flies. T. diaemi and S. diaemi associations with Diaemus youngi have not been previously reported in this region.

Outbreak of aggressions and transmission of rabies in human beings by vampire bats in northeastern Brazil

Outbreaks of attacks upon human beings by vampire bats seems to be a common phenomenon in several regions of Latin America, but the occurrence of rabies infection among humans bled by vampires, is relatively low. In the present study, two outbreaks of human rabies transmitted by common vampire bats (Desmodus rotundus) are described from Bahia State, Northeasthern Brazil, in 1991 and 1992. The first was recorded in Aporá where 308 people were bled by vampire bats and three of these die from this zoonosis. The 2nd outbreak occurred in Conde where only five people were bled by vampires, and two deaths by rabies were registered. Our data suggest that rabies transmitted by bats basically depends on the presence of virus in the vampire bat population and not on the number of humans bled by them.

Antigenic typing of brazilian rabies virus samples isolated from animals and humans, 1989-2000

Animal and human rabies samples isolated between 1989 and 2000 were typified by means of a monoclonal antibody panel against the viral nucleoprotein. The panel had been previously established to study the molecular epidemiology of rabies virus in the Americas. Samples were isolated in the Diagnostic Laboratory of the Pasteur Institute and in other rabies diagnostic centers in Brazil. In addition to the fixed virus samples CVS-31/96-IP, preserved in mouse brain, and PV-BHK/97, preserved in cell culture, a total of 330 rabies virus samples were isolated from dogs, cats, cattle, horses, bats, sheep, goat, swine, foxes, marmosets, coati and humans. Six antigenic variants that were compatible with the pre-established monoclonal antibodies panel were defined: numbers 2 (dog), 3 (Desmodus rotundus), 4 (Tadarida brasiliensis), 5 (vampire bat from Venezuela), 6 (Lasiurus cinereus) and Lab (reacted to all used antibodies). Six unknown profiles, not compatible with the panel, were also found. Samples isolated from insectivore bats showed the greatest variability and the most commonly isolated variant was variant-3 (Desmodus rotundus). These findings may be related to the existence of multiple independent transmission cycles, involving different bat species.

First record of Desmodus rotundus in urban area from the city of Olinda, Pernambuco, Northeastern Brazil: a case report

The objective of this report is to describe the first record of Desmodus rotundus in urban area from the city of Olinda, Pernambuco State, Northeastern Brazil, and to draw attention to the possible risk of rabies transmission in this place. After the complaint of a dog owner who observed three bats attacking his dog, images registering attacks of D. rotundus were captured with a video camera. From 09:00 p.m. on 13 February 2004 to 04:00 a.m. of the next day, a high frequency of haematophagic activity and the presence of several bites on the dog's body were observed. This finding represents a serious risk to public health. Thus, it is necessary to further study the bat fauna, with special attention to their feeding behaviour in this place, in order to better know their biology and to adopt pertinent control measures. This is, to our knowledge, the first record of D. rotundus in urban area of Olinda.

Rabies surveillance in bats in Northwestern State of São Paulo

Introduction Rabies is an important zoonosis that occurs in mammals, with bats acting as Lyssavirus reservoirs in urban, rural and natural areas. Rabies cases in bats have been recorded primarily in urban areas in Northwestern State of São Paulo since 1998. This study investigated the circulation of rabies virus by seeking to identify the virus in the brain in several species of bats in this region and by measuring rabies-virus neutralizing antibody levels in the hematophagous bat Desmodus rotundus. Methods From 2008 to 2012, 1,490 bat brain samples were sent to the Universidade Estadual Paulista (UNESP) Rabies Laboratory in Araçatuba, and 125 serum samples from vampire bats that were captured in this geographical region were analyzed. Results Rabies virus was detected in the brains of 26 (2%) of 1,314 non-hematophagous bats using the fluorescent antibody test (FAT) and the mouse inoculation test (MIT). None of the 176 hematophagous bat samples were positive for rabies virus when a virus detection test was utilized. Out of 125 vampire bat serum samples, 9 (7%) had levels of rabies virus neutralization antibodies (RVNAs) that were higher than 0.5IU/mL; 65% (81/125) had titers between 0.10IU/mL and 0.5IU/mL; and 28% (35/125) were negative for RVNAs using the simplified fluorescent inhibition microtest (SFIMT) in BHK21 cells. The observed positivity rate (1.7%) was higher than the average positivity rate of 1.3% that was previously found in this region. Conclusions The high percentage of vampire bats with neutralizing antibodies suggests that recent rabies virus exposure has occurred, indicating the necessity of surveillance measures in nearby regions that are at risk to avoid diffusion of the rabies virus and possible rabies occurrences.

First report of rabies in vampire bats (Desmodus rotundus) in an urban area, Ubatuba, São Paulo state, Brazil

The purpose of this report is to record the first case of a hematophagous bat (Desmodus rotundus) infected with rabies virus in an urban area in Brazil. To the authors' knowledge, this is the first such case in Latin America. After discovering a bat in his garden at 10 o'clock in the morning, a resident of Ubatuba municipality asked the Zoonosis Control Center team to visit his home. The animal was caught alive on the same day and sent to the Pasteur Institute laboratory, where it was identified as a Desmodus rotundus specimen. Standard tests for rabies diagnosis were carried out (direct immunofluorescence and viral isolation), and the results were positive. The presence of different species of (primarily insectivorous) bats in urban areas represents a serious public health problem. This case, however, is indicative of a much greater risk because the species in question has hematophagous habits, what means this animals has a low energy reserves and, therefore, its need to feed daily.

Antigenic and genetic characterization of the first rabies virus isolated from the bat Eumops perotis in Brazil

Although the main transmitters of rabies in Brazil are dogs and vampire bats, the role of other species such as insectivorous and frugivorous bats deserves special attention, as the rabies virus has been isolated from 36 bat species. This study describes the first isolation of the rabies virus from the insectivorous bat Eumops perotis. The infected animal was found in the city of Ribeirão Preto, São Paulo. The virus was identified by immunofluorescence antibody test (FAT) in central nervous system (CNS) samples, and the isolation was carried out in N2A cell culture and adult mice. The sample was submitted to antigenic typing using a panel of monoclonal antibodies (CDC/Atlanta/USA). The DNA sequence of the nucleoprotein gene located between nucleotides 102 and 1385 was aligned with homologous sequences from GenBank using the CLUSTAL/W method, and the alignment was used to build a neighbor-joining distance-based phylogenetic tree with the K-2-P model. CNS was negative by FAT, and only one mouse died after inoculation with a suspension from the bat's CNS. Antigenic typing gave a result that was not compatible with the patterns defined by the panel. Phylogenetic analysis showed that the virus isolated segregated into the same cluster related to other viruses isolated from insectivorous bats belonging to genus Nyctinomops ssp. (98.8% nucleotide identity with each other).

Rabies in the insectivorous bat Tadarida brasiliensis in Southeastern Brazil

This is the first recorded case of rabies in the insectivorous bat Tadarida brasiliensis in the State of S. Paulo, Southeastern Brazil. The infected bat was found in the afternoon while hanging on the internal wall of an urban building. This observation reinforces the notion as to the caution one must exercise regarding bats found in unusual situations.

Bat rabies in the north-northwestern regions of the state of São Paulo, Brazil: 1997-2002

OBJECTIVE: Reports on bat rabies in Brazil are sporadic and isolated. This study aimed at describing the detection of rabies virus in bats in the state of São Paulo. METHODS: A total of 7,393 bats from 235 municipalities of the north and northwestern areas of the state of São Paulo, Southeastern Brazil, were assessed according to their morphological and morphometric characteristics from 1997 to 2002. Fluorescent antibody test and mice inoculation were used for viral identification. RESULTS: Of all samples examined, 1.3% was rabies virus positive, ranging from 0.2% in 1997 to 1.6% in 2001. There were found 98 bats infected, 87 in the urban area. Fluorescent antibody test was detected in 77 positive samples, whereas 92 produced rabies signs in mice; incubation period ranging from 4 to 23 days. In 43 cities at least one rabid bat was observed. The highest proportion (33.7%) of rabies virus was found in Artibeus lituratus. Eptesicus and Myotis were the most frequent positive species (24.5%) of the Vespertilionidae family. The species Molossus molossus and Molossus rufus showed 14.3% positive bats. There were no differences in the distribution of positive rabies between females (33; 48.5%) and males (35; 51.5%). CONCLUSIONS: Rabies-infected bats were found in environments that pose a risk to both human and domestic animal population and there is a need for actions aiming at the control of these species and public education.

An outbreak of bat-transmitted human rabies in a village in the Brazilian Amazon

During 45 days without electrical power, 57 individuals (8.7% of the population) from the village of Antônio Dino (municipality of Turiaçu, Northeastern Brazil) were attacked by bats and 16 died from human rabies. The aim of the study was to analyze the factors associated with bat attacks and the development of human rabies. Of the 46 individuals, who suffered bat attacks, 36 (78.3%) were under 17 years of age. The risk factors associated with bat attacks were age under 17 years, having observed bats inside the bedroom and having been without electrical power in the house. Age under 17 years and having been without electrical power in the house were factors associated with human rabies.

Updated list of bat species positive for rabies in Brazil

This paper presents an updated list of bat species positive for rabies in Brazil. It was developed based on database research via the internet, of international and national literature and annals of the most important technical and scientific meetings related to rabies and chiroptera in Brazil from 1996 to 2009. The new list of rabies positive bats consists of 41 species, belonging to 25 genera and three families: Phyllostomidae 43.9%, Vespertilionidae 29.3% and Molossidae 26.8%. In addition, questions were raised regarding the lack of data, including sex, age, circumstances and location of bat capture and incomplete and outdated species identification. Results of genetic and antigenic studies performed on Brazilian rabies positive bats were shown.

BAT-BORNE RABIES IN LATIN AMERICA

The situation of rabies in America is complex: rabies in dogs has decreased dramatically, but bats are increasingly recognized as natural reservoirs of other rabies variants. Here, bat species known to be rabies-positive with different antigenic variants, are summarized in relation to bat conservation status across Latin America. Rabies virus is widespread in Latin American bat species, 22.5%75 of bat species have been confirmed as rabies-positive. Most bat species found rabies positive are classified by the International Union for Conservation of Nature as “Least Concern”. According to diet type, insectivorous bats had the most species known as rabies reservoirs, while in proportion hematophagous bats were the most important. Research at coarse spatial scales must strive to understand rabies ecology; basic information on distribution and population dynamics of many Latin American and Caribbean bat species is needed; and detailed information on effects of landscape change in driving bat-borne rabies outbreaks remains unassessed. Finally, integrated approaches including public health, ecology, and conservation biology are needed to understand and prevent emergent diseases in bats.

Growth and differentiation on a trypanosome of the subgenus Schizotrypanum from the bat Phyllostomus hastatus

The effects of temperature, pH, osmolarity and aeration on the growth and differentiation of a trypanosome ofthe subgenus Schizotrypanum isolatedfrom the bat Phyllostomus hastatus were studied. In general, the growth characteristics ofthe flagellate were similar to those of Trypanosoma (Schizotrypanum) cruzi. However, the parasite did not growth at 33 or 37C. Increase in the osmolarity and aeration promoted growth at 33C. Significant metacyclogenesis was detected only in the growth condition where maximal growth occured (28C, pH 7.3, 380m0s/kg, in tissue cullure flasks), at the end ofthe exponential growth phase. The begining of the metacyclogenesis process was coincident with most glucose utilization and lowest pH. During metacyclogenesis both culture medium pH and osmolarity increased steadly.

Cat infected by a variant of bat rabies virus in a 29-year disease-free urban area of southern Brazil

INTRODUCTION: After 29 years, rabies was detected in a cat in Curitiba, southern Brazil. METHODS: The fluorescent antibody test (FAT) and mouse inoculation test (MIT) were performed on central nervous system (CNS) samples. RESULTS: Direct immunofluorescence was negative, but the biological test was positive and rabies virus was characterized as variant 4 (from Tadarida brasiliensis). CONCLUSIONS: Reappearance of rabies in domestic animals warns of sylvatic-aerial risk of infection and the necessity of monitoring bats in historically rabies-free areas.