Increased detection of rabies virus in bats in Ceará State (Northeast Brazil) after implementation of a passive surveillance programme

The intensification of dog, cat and livestock vaccination campaigns significantly reduced rabies cases in humans and domestic animals in Ceará State, Brazil. However, sylvatic animals—bats (order Chiroptera), wild canids, raccoons and non‐human primates— remain as reservoirs for the virus. Our hypothesis is that surveillance and monitoring of rabies virus in bats, especially passive surveillance, is of fundamental importance, besides the implementation of health education and strengthening of surveillance actions in humans exposed to aggressions. Thus, we assessed the occurrence of rabies virus in animals focusing on bats, before and after launching of the Sylvatic Rabies Surveillance Program in 2010. Surveillance data from the 184 municipalities of Ceará State were analysed, collected during the periods 2003–2010 (active surveillance) and 2011–2016 (passive surveillance), respectively. A total of 13,543 mammalian samples were received for rabies diagnosis from 2003 to 2016. Of these, 10,960 were from dogs or cats (80.9%), 1,180 from bats (8.7%), 806 from other sylvatic animals (foxes, marmosets, raccoons; 6.0%) and 597 from herbivores (cattle, goats, sheep, equines, pigs; 4.4%). A total of 588 (4.3%) samples were positive for rabies. About 8.4% (99/1,180) of the bat samples were infected with rabies virus, 92 (92.9%) of these were from non‐haematophagous bat species and 7 (7.1%) from haematophagous species. The number of bat samples received and infection rates increased considerably, after a shift from active surveillance (9/355 [2.5%] samples positive), to passive surveillance (90/825 [10.9%] samples positive). Surveillance of rabies virus in bats is fundamental for human and domestic animal health in Ceará State. Bats have to be considered as targets in surveillance and control programmes. Virus lineages should be characterized to increase knowledge on transmission dynamics of sylvatic rabies virus to domestic animals and the human population, and to provide additional evidence for planning and implementation of improved control measures.     

Evaluating the public health response to a mass bat exposure—Wyoming, 2017

Mass bat exposures (MBEs) occur when multiple people are exposed to a bat or a bat colony, often over an extended period. In August 2017, a public health investigation was started in response to an MBE that occurred during May–August 2017 at a national park research station in Wyoming. We identified 176 people who had slept primarily in two lodges (Lodges A and B) at the research station, and successfully contacted 165 (93.8%) of these individuals. Risk assessments (RAs) were administered to all 165 individuals to determine degree and type of exposures to bats (e.g., biting or scratching). Exposure status for research station guests was classified as “non‐exposed,” “low risk” or “high risk,” and counselling was provided to guide post‐exposure prophylaxis (PEP) recommendations. Prior to public health notification and intervention, 19 persons made the decision to pursue PEP. The healthcare‐seeking behaviours of this group were taken to represent outcomes in the absence of public health intervention. (These persons received a RA, and their risk classification was retrospectively assigned.) Approximately 1–2 weeks after conducting the RAs, we conducted a follow‐up survey to determine whether recommendations regarding PEP were ultimately followed. The proportion of individuals that unnecessarily pursued PEP was higher among the 19 individuals that sought health care prior to receiving the RA (p < 0.00001). Among those receiving the RA first, all persons classified as high risk followed public health guidance to seek PEP treatment. Despite this, upon re‐interview, only 21/79 (26.6%) of guests could accurately recall their risk classification, with most people (55.7%) overestimating their risk. Study findings demonstrate that early public health interventions such as RAs can reduce unnecessary use of PEP and that messaging used during rabies counselling should be clear.     

Avoiding bites and scratches? Understanding the public health implication of human–bat interactions in Ghana

Zoonotic pathogens cause an estimated 70% of emerging and re‐emerging infectious diseases in humans, affecting various aspects of human development on a global scale. The significance of bats as a source of emerging infectious diseases is being progressively appreciated. This study was undertaken post‐Ebola virus disease in West Africa and assessed the public health implications of human–bat interactions by exploring the reasons for contact between humans and bats, as well as reported actions taken upon experiencing bat bites or scratches. The paper highlights the nuances of human–bat interactions, stressing zoonotic disease risk awareness as well as the sources of information. The study used questionnaires to solicit information from 788 respondents in five communities with significant bat populations. We show that bat consumption was one of the main reasons for human–bat interactions. More men across the various communities ate bat meat. Only a small number of respondents (4.4%) reported being bitten by a bat, and 6.1% had been scratched by a bat. More than 21% had come into direct contact with bat blood. An even lower number went to the hospital after been bitten or scratched by bats. There was little knowledge on post‐exposure management. The most common places human–bat interactions occurred were at home and on farms. Seventy‐three per cent of the respondents believed that bats carried diseases, with Ebola virus disease being the most mentioned. Respondents indicated that the way they interacted with bats had not changed, even though they believed bats carried diseases and 46% stated that they had not changed the way they interacted with bats over the last two years. Apart from providing information on avoiding bites and scratches, a more holistic framework is needed to reduce human–bat interactions. The paper recommends a comprehensive and coordinated approach to optimizing an effective response to a potential bat‐borne zoonotic disease spillover.     

Prevention educational program of human rabies transmitted by bats in rain forest preserved area of southern Brazilian coast

Guaraqueçaba city is a rain forest environmental protected area located on the southern coast of Brazil. Recently, the local Animal Health Service has noticed haematophagous bats feeding from humans and domestic animals, as well as bat colonies located in houses and public schools. In 2007, two non‐haematophagous bats were tested positive by direct immunofluorescence for rabies in a nearby city. Native fauna and environmental laws protect non‐haematophagous bats in Brazilian preserved areas such as Guaraqueçaba, making non‐haematophagous bat population control almost impossible. Accordingly, the aim of this study was to evaluate a simple and feasible educational protocol applied by a multi‐institutional task force in local elementary schools to prevent rabies transmitted by bats. Information was transmitted to children by video, lectures and oral question–answer section; evaluation was made by written questionnaires to teachers and students. Interinstitutional task force included public and animal health public services, a federal university and the city secretary of environment, of education, of agriculture and of animal health, and also participation of local community. Information was effectively absorbed by children when evaluated just after being given. As important, questionnaires showed that handling and playing with bats at day time was common in several elementary school students, exposing themselves to what may represent higher risk of rabies transmission than haematophagous bat feeding directly from humans. Training of teachers and students may effectively prevent rabies by bats in such communities. Insertion of this subject into science content of local elementary school educational programme was proposed in order to establish a continuing education programme on rabies transmitted by bats in environmental preserved areas.     

Identification of focus areas for Australian Bat Lyssavirus potential exposure prevention in the Metro North Hospital and Health Service region

Australian Bat Lyssavirus (ABLV) is a fatal rabies‐like disease spread to humans from bats. All people who report bat bites or scratches in Queensland are considered potentially exposed to ABLV and are followed up and treated to prevent ABLV. Preventing members of the public intentionally interacting with bats will reduce the number of potential exposures to ABLV. In order to target public health messaging, this study examines the epidemiology of potential ABLV exposures in Metro North Hospital and Health Service (HHS), a region of Queensland that encompasses metro and rural areas in the south‐east of the state. People who intentionally handled bats during the study period were more likely to be adult (93%), male (60%), scratched (51%) by a megabat (72%) and been potentially exposed while rescuing the bat when it was trapped or injured (72%). The number of potential exposures reported in Queensland has increased since 2013; the same year, a Queensland child died of ABLV. Seasonally, exposures are more common during bat breeding and nursing periods when bats are more active (summer to autumn). Although there were more notifications in a band stretching north from the inner city to northern metro suburbs, notification rates were higher in large rural statistical areas in the north of the HHS. These data will be used to develop geographically targeted ABLV prevention messaging for the general public.     

Faeces as a novel material to estimate lyssavirus prevalence in bat populations

Rabies is caused by infection with a lyssavirus. Bat rabies is of concern for both public health and bat conservation. The current method for lyssavirus prevalence studies in bat populations is by oral swabbing, which is invasive for the bats, dangerous for handlers, time‐consuming and expensive. In many situations, such sampling is not feasible, and hence, our understanding of epidemiology of bat rabies is limited. Faeces are usually easy to collect from bat colonies without disturbing the bats and thus could be a practical and feasible material for lyssavirus prevalence studies. To further explore this idea, we performed virological analysis on faecal pellets and oral swabs of seven serotine bats (Eptesicus serotinus) that were positive for European bat 1 lyssavirus in the brain. We also performed immunohistochemical and virological analyses on digestive tract samples of these bats to determine potential sources of lyssavirus in the faeces. We found that lyssavirus detection by RT‐qPCR was nearly as sensitive in faecal pellets (6/7 bats positive, 86%) as in oral swabs (7/7 bats positive, 100%). The likely source of lyssavirus in the faeces was virus excreted into the oral cavity from the salivary glands (5/6 bats positive by immunohistochemistry and RT‐qPCR) or tongue (3/4 bats positive by immunohistochemistry) and swallowed with saliva. Virus could not be isolated from any of the seven faecal pellets, suggesting the lyssavirus detected in faeces is not infectious. Lyssavirus detection in the majority of faecal pellets of infected bats shows that this novel material should be further explored for lyssavirus prevalence studies in bats.     

Evidence of Australian bat lyssavirus infection in diverse Australian bat taxa

Historically, Australia was considered free of rabies and rabieslike viruses. Thus, the identification of Australian bat lyssavirus (ABLV) in 1996 in a debilitated bat found by a member of the public precipitated both public health consternation and a revision of lyssavirus taxonomy. Subsequent observational studies sought to elaborate the occurrence and frequency of ABLV infection in Australian bats. This paper describes the taxonomic diversity of bat species showing evidence of ABLV infection to better inform public health considerations. Blood and/or brain samples were collected from two cohorts of bats (wild‐caught and diagnostic submissions) from four Australian states or territories between April 1996 and October 2002. Fresh brain impression smears were tested for ABLV antigen using fluorescein‐labelled anti‐rabies monoclonal globulin (CENTOCOR) in a direct fluorescent antibody test; sera were tested for the presence of neutralising antibodies using a rapid fluorescent focus inhibition test. A total of 3,217 samples from 2,633 bats were collected and screened: brain samples from 1,461 wild‐caught bats and 1,086 submitted bats from at least 16 genera and seven families, and blood samples from 656 wild‐caught bats and 14 submitted bats from 14 genera and seven families. Evidence of ABLV infection was found in five of the six families of bats occurring in Australia, and in three of the four Australian states/territories surveyed, supporting the historic presence of the virus in Australia. While the infection prevalence in the wild‐caught cohort is evidently low, the significantly higher infection prevalence in rescued bats in urban settings represents a clear and present public health significance because of the higher risk of human exposure.     

Outbreaks of attacks by hematophagous bats in isolated riverine communities in the Brazilian Amazon: a challenge to rabies control

Human rabies has re-emerged in Latin America due to bat associated transmission. We present data related to attacks by hematophagous bats in three riverine communities in the Rio Negro basin, Brazilian Amazon. A cross-sectional survey was carried out to obtain demographic and epidemiological data through interviews with 201 inhabitants. A total of 721 bat attacks with bites took place from 2004 to 2006, 238 (33%) reported by residents in Campinas do Rio Preto, 329 (46%) in águas Vivas and 154 (21%) in the community of Malalahá. Incidence density among surveyed inhabitants was 84 attacks/100 persons-years in Campinas do Rio Preto, 249 attacks/100 persons-years in águas Vivas and 81 attacks/100 persons-years in Malalahá. The proportion of surveyed inhabitants bled by bats at least once was 67% (63/94) in Campinas do Rio Preto, 96% (42/44) in águas Vivas and 62% (39/63) in Malalahá. Among subjects bled by bats, the average number of bites was 4.6 ± 4.2 standard deviations (SD) in Campinas do Rio Preto, 8 ± 6 SD in águas Vivas and 4.1 ± 3.9 SD in Malalahá. Regarding houses, 67% (26/39) had animals in the peridomestic environment (chickens and/or dogs) and all were vulnerable to bats due to gaps in the walls and/or in the windows and doors. In 13 dwellings, rudimentary protection against bats through the fixation of fishing nets and/or straw nets to the windows and other openings was observed. Among dwellers reporting attacks, 48% (68/144) received the full post-exposure anti-rabies vaccination protocol with five doses of diploid human cell vaccine, 28% (39/144) received an incomplete schedule (1-4 doses), and 26% (37/144) did not receive any dose. No cases of rabies were reported during the study; however, regular pre-exposure vaccination in the studied populations must be considered.     

Bat rabies in alberta 1979-1982

The infection rate among eight species of bats submitted for rabies diagnosis in Alberta during 1979-82 was 4.6%. Prevalence of rabies was greatest (24%) for hoary bats Lasiurus cinereus, while the big brown bat Eptesicus fuscus was the species in which rabies was most commonly diagnosed, and the species submitted most frequently for rabies diagnosis was the little brown bat Myotis lucifugus. The rabies infection rate among male hoary bats was significantly greater than in either sex of all other submitted species. The frequency of rabies diagnosis in hoary bats submitted during 1979-82 was also significantly higher than in those submitted between 1971 and 1978. There has been a significant decrease in the rabies prevalence or infection rate of little brown bats since 1971-78.     

Characteristics of bat rabies in Alberta.

Rabies in bats was monitored in Alberta from 1971 to 1978 Big brown bats replaced silver-haired bats as the species most frequently reported rabid during these years. Rabies infection was comparatively high among little brown bats in central Alberta in 1973 and has subsequently declined. Only one rabid little brown bat was discovered in southern Alberta which is populated by a different subspecies. Outbreaks of rabies in little brown and big brown bat colonies tended to be brief events. Observations of free-ranging bats with probable furious rabies suggested that bats do not generally identify humans as targets for attack. Independent trends in infection rates suggested that spread of rabies is primarily intraspecific but there is evidence that migratory bats play a role in introduction and maintenance of rabies in northern temperate bat communities. The dynamics of bat rabies in Alberta are discussed.     

Trends in national surveillance for rabies among bats in the United States (1993-2000)

OBJECTIVE: To describe surveillance trends and epidemiologic features of rabies in bats in the United States, focusing on 3 bat species primarily associated with variants of the rabies virus that affect humans. DESIGN: Retrospective study. ANIMALS: 31,380 bats. PROCEDURE: Data on rabies for bats identified to species and reported by state laboratories from 1993 to 2000 were analyzed, focusing on silver-haired, eastern pipistrelle, and Brazilian free-tailed bats. Categoric variables were derived from other provided information. RESULTS: Data were reported from 37 states during the study interval; complete species-specific data were not reported by any state for the entire interval. Bats primarily associated with rabies virus variants affecting humans were more likely to yield positive test results for rabies (22.7%), compared with all other bats (5.5%) in most seasons and from most regions of the United States. However, certain other bat species had higher percentages of positive results. Risk of positive results was highest in the fall and highest among bats originating in the southwestern United States. CONCLUSIONS AND CLINICAL RELEVANCE: Increased risk of rabies among certain groups of bat species was consistently found across seasons and most geographic regions of the United States. Results were in general agreement with those of previous studies conducted within smaller geographic regions. There are ongoing efforts to improve surveillance of rabies in bats, although surveillance is incomplete in some regions.     

Detection of European bat lyssavirus 2 (EBLV-2) in a Daubenton's bat (Myotis daubentonii) from Magdeburg, Germany

In Europe bat rabies in Daubenton's bats (Myotisdaubentonii) and in Pond bats (Myotis dasycneme) caused by the European bat lyssavirus 2 (EBLV-2) has been confirmed in less than 20 cases to date. Here we report the second encounter of this virus species in Germany. A Daubenton's bat found grounded in the zoological garden in Magdeburg died shortly after. In the frame of a retrospective study the bat carcass was eventually transferred to the national reference laboratory for rabies at the Friedrich-Loeffler-Institute for rabies diagnosis. Lyssavirus was isolated and characterized as EBLV-2.     

First Isolation of a Rabid Bat Infected with European Bat Lyssavirus in Luxembourg

Rabid bats are regularly reported in Europe, especially in countries that have implemented a bat surveillance network. In May 2013, bat rabies was evidenced for the first time in Luxembourg (southern city of Differdange). The rabies virus, an EBLV‐1b strain, was diagnosed in a serotine bat that bit a 29‐year‐old male person while he was asleep. The man received rapidly a post‐exposure RABV treatment and was put under strict medical supervision.     

Potential exposure to Australian bat lyssavirus is unlikely to prevent future bat handling among adults in South East Queensland

Despite ongoing public health messages about the risks associated with bat contact, the number of potential exposures to Australian bat lyssavirus (ABLV) due to intentional handling by members of the general public in Queensland has remained high. We sought to better understand the reasons for intentional handling among these members of the public who reported their potential exposure to inform future public health messages. We interviewed adults who resided in a defined geographic area in South East Queensland and notified potential exposure to ABLV due to intentional handling of bats by telephone between 1 January 2012 and 31 December 2013. The participation rate was 54%. Adults who reported they had intentionally handled bats in South East Queensland indicated high levels of knowledge and perception of a moderately high risk associated with bats with overall low intentions to handle bats in the future. However, substantial proportions of people would attempt to handle bats again in some circumstances, particularly to protect their children or pets. Fifty‐two percent indicated that they would handle a bat if a child was about to pick up or touch a live bat, and 49% would intervene if a pet was interacting with a bat. Future public health communications should recognize the situations in which even people with highrisk perceptions of bats will attempt to handle them. Public health messages currently focus on avoidance of bats in all circumstances and recommend calling in a trained vaccinated handler, but messaging directed at adults for circumstances where children or pets may be potentially exposed should provide safe immediate management options.     

Knowledge,Attitudes and Practices of Law Enforcement Officers on Rabies and Animal Control Issues in Kansas

Rabies is a deadly zoonoses endemic in the United States, including Kansas. Animal control programmes that emphasize vaccination of dogs and cats, removal of stray animals and enforcement of licensure programmes have historically been essential in reducing the risk of rabies exposures to humans (Beran, 1991). Kansas does not mandate the use of animal control officers [ACOs] and in areas where there is no designated animal control officer, law enforcement officers [LEOs] are required to fill that role. Little is known about LEOs' knowledge of rabies, their current practices in responding to animal‐related calls or if they receive any specialized training to perform the duties of an ACO. A web‐based, voluntary and anonymous survey was sent to law enforcement officers in Kansas in January 2014. The survey included questions about animal control practices and a self‐assessment of rabies knowledge. The response rate was 16.2%. All respondents indicated LEOs will respond to animal‐related calls, even if there was an ACO available in their department or jurisdiction. A majority of respondents indicated they had not received training on safe animal handling (62.9%, 61/97) or zoonoses prevention (85.6%, 83/97), even though a strong majority considered such training important (89.7% and 79.4%, respectively). Most respondents (>80%) were able to correctly identify animals capable of transmitting rabies but were less aware of how rabies was transmitted or the severity of rabies in humans. Our results demonstrate that Kansas LEOs perform animal control duties, many without the proper training, even though most consider such training to be important to be able to perform their duties safely. Training on safe animal handling and zoonoses prevention should be provided to all LEOs in Kansas to enable them to safely execute their duties and provide timely and accurate information to citizens regarding rabies prevention.     

Zoonotic pathogens isolated from wild animals and environmental samples at two California wildlife hospitals

During 2010, 48 states and Puerto Rico reported 6,154 rabid animals and 2 human rabies cases to the CDC, representing an 8% decrease from the 6,690 rabid animals and 4 human cases reported in 2009. Hawaii and Mississippi did not report any laboratory-confirmed rabid animals during 2010. Approximately 92% of reported rabid animals were wildlife. Relative contributions by the major animal groups were as follows: 2,246 raccoons (36.5%), 1,448 skunks (23.5%), 1,430 bats (23.2%), 429 foxes (6.9%), 303 cats (4.9%), 71 cattle (1.1 %), and 69 dogs (1.1 %). Compared with 2009, number of reported rabid animals decreased across all animal types with the exception of a 1 % increase in the number of reported rabid cats. Two cases of rabies involving humans were reported from Louisiana and Wisconsin in 2010. Louisiana reported an imported human rabies case involving a 19-year-old male migrant farm worker who had a history of a vampire bat (Desmodus rotundus) bite received while in Mexico. This represents the first human rabies case reported in the United States confirmed to have been caused by a vampire bat rabies virus variant. Wisconsin reported a human rabies case involving a 70-year-old male that was confirmed to have been caused by a rabies virus variant associated with tri-colored bats (Perimyotis subflavus).     

Veterinary surgeon's guide to Australian bat lyssavirus

Veterinary surgeons in Australia must be aware of the emerging viral diseases and their potential effects on public health generally and, more specifically, on the veterinary profession. Australian bat lyssavirus was identified in 1996 and causes rabies-like disease in bats and humans. Two humans from Queensland have died of Australian bat lyssavirus encephalitis. Surveillance has shown that all Australian bats must be considered carriers of this new virus, therefore protective apparel should be used when handling bats. The pre-exposure regimen of inactivated rabies vaccine (Pasteur Mérieux) provides protection against infection. As part of the preventive regimen, at risk groups, such as veterinary surgeons, should seriously consider pre-exposure rabies vaccination. The post-exposure protocol involves administration of human rabies immunoglobulins and five intramuscular injections of the inactivated rabies vaccine.     

Experimental infection of Artibeus intermedius with a vampire bat rabies virus

Experimental infection of Artibeus intermedius, the great fruit-eating bat, was performed with vampire bat rabies isolates. Bats (n = 35) were captured in the wild and quarantined prior to experimental infection. No rabies antibodies were detected by rapid fluorescent focus inhibition test (RFFIT) prior to infection. Three doses of rabies virus (RV) and three different routes of infection were used. One out of 35 bats died without showing any clinical signs at day 14 and was positive for rabies. None of the 34 other bats showed clinical signs for rabies, but high antibody titers were detected post-inoculation, suggesting either innate immune response to the vampire bat rabies virus or possible pre-exposure to RV and inoculation leading to a booster effect. Rabies virus was detected by hemi-nested RT-PCR (hnRT-PCR) in the brain (n = 3), stomach (n = 1) of bats that were negative by immunofluorescence and that survived rabies infection. The bat that died on day 14 was positive by hnRT-PCR on the brain, heart and liver. These results suggest that either previous non-lethal exposure to RV or natural low susceptibility to vampire bat viruses somehow protected Artibeus intermedius from clinical rabies infection leading to a marginal lethality effect on this bats species population in the wild.