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.     

Bats, cats, and rabies in an urban community

Bats are the primary vectors of rabies in humans in the United States. In the urban environment they generally are found within buildings where they may bite people or be attacked by cats or dogs. Given the high probability that any bat that bites a person may be rabid, antirabies prophylaxis should be administered as soon as possible after the incident. This should not be delayed pending laboratory results on the bat. Children should be taught to avoid contact with moribund bats. Cats are more likely to be involved with rabid bats than dogs, but they are less likely to be vaccinated against rabies. The occasional rabid cat in an urban community may have acquired its infection from a bat. Therefore, it is vital that communities enforce rabies vaccination for cats as well as dogs.     

Chromosomal abnormalities and tumor development: from genes to therapeutic mechanisms

PURPOSE: To summarize the epidemiologic, diagnostic, and clinical features of the 32 laboratory-confirmed cases of human rabies diagnosed in the United States from 1980 to 1996. DATA SOURCES: Data were obtained from case reports of human rabies submitted to the Centers for Disease Control and Prevention by state or local health authorities. STUDY SELECTION: All cases of human rabies reported in the United States from 1980 to 1996 in which infection with rabies virus was confirmed by laboratory studies. DATA EXTRACTION: Patients were reviewed for demographic characteristics, exposure history, rabies prophylaxis, clinical presentation, treatment, clinical course, diagnostic laboratory tests, identification of rabies virus variants, and the number of medical personnel or family members who required postexposure prophylaxis after coming in contact with an exposed person. DATA SYNTHESIS: 32 cases of human rabies were reported from 20 states. Patients ranged in age from 4 to 82 years and were predominantly male (63%). Most patients (25 of 32) had no definite history of an animal bite or other event associated with rabies virus transmission. Of the 32 cases, 17 (53%) were associated with rabies virus variants found in insectivorous bats, 12 (38%) with variants found in domestic dogs outside the United States, 2 (6%) with variants found in indigenous domestic dogs, and 1 (3%) with a variant found in indigenous skunks. Among the 7 patients with a definite exposure history, 6 cases were attributable to dog bites received in foreign countries and 1 was attributable to a bat bite received in the United States. In 12 of the 32 patients (38%), rabies was not clinically suspected and was diagnosed after death. In the remaining 20 cases (63%), the diagnosis of rabies was considered before death and samples were obtained specifically for laboratory confirmation a median of 7 days (range, 3 to 17 days) after the onset of clinical signs. Of the clinical differences between patients in whom rabies was diagnosed before death and those in whom it was diagnosed after death, the presence of hydrophobia or aerophobia was significantly associated with antemortem diagnosis (odds ratio, 11.0 [95% CI, 1.05 to 273.34]). The median number of medical personnel or familial contacts of the patients who received postexposure prophylaxis was 54 per patient (range, 4 to 179). None of the 32 patients with rabies received postexposure prophylaxis before the onset of clinical disease. CONCLUSIONS: In the United States, human rabies is rare but probably underdiagnosed. Rabies should be included in the differential diagnosis of any case of acute, rapidly progressing encephalitis, even if the patient does not recall being bitten by an animal. In addition to situations involving an animal bite, a scratch from an animal, or contact of mucous membranes with infectious saliva, postexposure prophylaxis should be considered if the history indicates that a bat was physically present, even if the person is unable to reliably report contact that could have resulted in a bite. Such a situation may arise when a bat bite causes an insignificant wound or the circumstances do not allow recognition of contact, such as when a bat is found in the room of a sleeping person or near a previously unattended child.     

Postexposure treatment of rabies in Pakistan

To evaluate compliance with current World Health Organization (WHO) guidelines for postexposure treatment (PET) of rabies, we interviewed all animal bite victims seeking treatment on the same day of each week from 28 December 1994 through 18 January 1995 at the Civil Hospital of Karachi (Pakistan), a major referral center. Of the 143 patients studied, 109 (76%) sustained bleeding transdermal bites (WHO category III). Overall, wounds were not washed with soap or an antiseptic in 69% of victims. All victims received 5% sheep brain-derived vaccine, and only three of the 109 victims with category III bites received rabies immune globulin. PET of rabies in Karachi was deficient by all WHO standards. Although there is a great urgency to improve PET, it will remain a costly and inefficient method of controlling rabies. Reduction of rabies reservoirs is required to decrease human deaths due to rabies in Pakistan and other developing countries in which canine rabies is endemic.     

Protective activity of a murine monoclonal antibody against European bat lyssavirus 1 (EBL1) infection in mice

A mouse model was designed to test in vivo the efficacy of rabies immune globulins and specific neutralizing monoclonal antibodies to prevent European bat lyssavirus 1 infection. Human or equine rabies immune globulins previously found to contain variable amounts of neutralizing bat lyssavirus crossreactive antibodies were passively transferred to mice receiving intramuscularly a lethal dose of bat lyssavirus type 1. Immune globulins did not protect mice well against bat lyssavirus 1 whereas they reduced the mortality caused by rabies virus. In contrast, mice inoculated with bat lyssavirus 1 or rabies virus survived when passively immunized with bat lyssavirus 1 specific monoclonal antibody (mAb 8-2). This monoclonal antibody, an IgG2 alpha, recognized an epitope located in the antigenic site IIa of rabies glycoprotein. A mutation replacing the lysine 198 by glutamate in a rabies variant abrogated sensitivity to this neutralizing antibody. Because of its broad neutralizing spectrum against wild virus isolates, including European bat lyssaviruses, this monoclonal antibody should be a good candidate for rabies immune globulin replacement. It could improve efficacy of rabies vaccination, used either alone or in conjunction with human rabies immune globulins or monoclonal antibody cocktail to supplement their lack of crossreactivity to European bat lyssavirus 1.     

The Inventory of Functional Status-Dialysis: development and testing

Pet and wildlife populations are a potential source of various public health problems, and injuries and complications due to animal bites and scratches are the most obvious. As no population based data on the frequency of animal bites were available at a national level in Switzerland, a study was conducted by the Swiss Sentinel Surveillance Network. The objectives of this study were to estimate the incidence of medical consultations due to bite and scratch injuries in humans caused by vertebrate animals, to identify possible risk factors, and to assess bite management habits in primary health care. An annual bite and scratch incidence rate of 325 per 100,000 population was estimated. Consultations peaked during the summer months and geographical differences in the reported incidence were observed. Dogs accounted for more than 60% and cats for about 25% of all cases reported. Animal bites and scratches were frequent in persons under 20 years of age. In most ages, the incidence was higher among women than among men, but not in children under the age of ten years. The incidence of cat bites was especially high in adult women. Bites to the head and neck were most frequent in infants and young children and accounted for approximately one third of the reported cases in this age group. Patients sought medical care principally for primary wound care (52.0%) and for vaccination advice (29.6%). Rabies postexposure prophylaxis was initiated in 1.1% of patients. Wound infection was reported in 10.9% of cases, with cat bites/scratches being more often infected than injuries due to dogs. Hospitalization was reported in 0.3 % of patients. Data from the emergency department of two district hospitals showed that head and neck injuries were more frequent in out-patients and a higher proportion of persons presented with wound infections (14.1%). The hospitalization rate for emergency department visits was 4.7%. Animal bites and scratches are common events in Switzerland. They represent a public health issue of growing importance due to the steadily increasing pet population. A practice based sentinel surveillance system may be an appropriate tool to monitor national trends in animal bites and scratches.     

Rabies surveillance in the United States during 1997

In 1997, 49 states, the District of Columbia, and Puerto Rico reported 8,509 cases of rabies in nonhuman animals and 4 cases in human beings to the Centers for Disease Control and Prevention. Nearly 93% (7,899) were wild animals, whereas 7% (610) were domestic species. The total number of reported cases increased 19.4% from that of 1996 (7,128 cases). Increases were apparent in each of the major species groups, with the exception of cattle. The relative contributions of these groups to the total reported for 1997 were as follows: raccoons (50.5%; 4,300 cases), skunks (24.0%; 2,040), bats (11.3%; 958), foxes (5.3%; 448), cats (3.5%; 300), dogs (1.5%; 126), and cattle (1.4%; 122). The 958 cases of rabies reported in bats represented a 29.3% increase over the total reported for 1996 and the greatest number reported since 1984, with cases reported by 46 of the 48 contiguous states. The epizootic of rabies in raccoons expanded into Ohio in 1997 and now includes 19 states and the District of Columbia. Thirteen states, where rabies in raccoons is enzootic, reported increases over 1996 in total numbers of reported cases. New York (1,264 cases), North Carolina (879), Virginia (690), and Maryland (619) reported the greatest numbers of cases [corrected]. Five states reported increases that exceeded 50%, compared with cases reported in 1996: Ohio (673.3%; 15 cases in 1996 to 116 in 1997). Massachusetts (144.3%; 115 to 281), South Carolina (97.9%; 96 to 190), Connecticut (97.4%; 274 to 541), and Maine (86.3%; 131 to 244). Cases of rabies associated with foci of rabies in foxes in west central Texas and in dogs and coyotes in southern Texas continued to decline, with this state reporting 78.3% fewer rabid foxes (13 cases), 26.7% fewer rabid dogs (11), and 63.2% fewer rabid coyotes (7) during 1997, compared with 1996. Reported cases of rabies in cats (300) and dogs (126) increased 12.8% and 13.5%, respectively, whereas cases in cattle (122) decreased by 6.9%. Thirty states, the District of Columbia, and Puerto Rico reported increases in rabies in animals during 1997, compared with decreases reported by 31 states and the District of Columbia in 1996. One state (Mississippi; 5 cases) remained unchanged. Hawaii was the only state that did not report a case of rabies in 1997. Four indigenously acquired cases of rabies reported in human beings were the result of infection with rabies virus variants associated with bats.     

Neural computations for sound pattern recognition: evidence for summation of an array of frequency filters in an echolocating bat

Microchiropteran bats use an auditory sonar system for orientation and prey capture. Many bats use highly structured constant-frequency (CF) and frequency-modulated (FM) sonar orientation signals. Mechanisms for sound pattern recognition are important for the perception of these and other types of auditory signals. The processing and recognition of FM sound components appears to be important for certain complex perceptual tasks, including target distance perception. I have conducted behavioral studies using artificial echoes to simulate the conditions of a bat flying toward a target. An innate vocalization response of the bat to the simulated approaching target was used to assess the ability of the bat to analyze the structure of and extract distance information from different types of synthetic FM sound patterns. The bat's performance depended on the structure of the artificial echo. The pattern recognition performance of the bats was similar when they were presented with either a naturally structured artificial CF/FM echo or an artificial CF/FM echo containing an FM component consisting of a series of pure tone steps. The ability of the bats to recognize appropriately the structure of an FM signal constructed from a sequence of pure tones depended on the number of pure tone steps in the series. Noctilio was able to recognize FM sound patterns containing 99 or greater pure tone steps. The minimum required number of pure tone steps could be distributed over different frequency ranges. The bats were able to resolve individual tone steps in the series that were separated by at least 100 Hz.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dog bites in children admitted to Pennsylvania trauma centers

Dog bites are a major public health problem in the pediatric population, requiring emergency treatment for wound repair and possible hospitalization in a trauma center. Data from the Pennsylvania Trauma Outcome Study were analyzed, and the records of 183 pediatric dog bite patients from 1990 to 1995 were evaluated. Dog bites were found to constitute a very small proportion of the total pediatric admissions to Pennsylvania trauma centers; however, the findings were similar to other reported studies.     

Clinical and histopathologic correlation of midge bites

Many species of files viciously bite humans and animals. I had the opportunity to observe such bites by the gnat Leptoconops torrens during a recent epidemic that occurred in an inland desert area of California. The bite may produce an urticarial wheal, but, more characteristically, it induces formation of a hard, indolent, pruritic papule. In biopsy specimens taken within three days after the bite, the superficial infiltrate was composed or lymphocytes and histiocytes, while eosinophils were the preponderant cell found in the deeper dermis and subcutaneous fat. These clinical and histopathologic findings are similar to those reported for the bite of the blackfly, Simulium.     

Complex sound analysis in the FM bat Eptesicus fuscus, correlated with structural parameters of frequency modulated signals

Big brown bats, Eptesicus fuscus, were presented with artificial frequency modulated (FM) echoes that simulated an object becoming progressively closer to the bat. A stereotyped approach phase behavioral response of the bat to the virtual approaching target was used to determine the ability of the bat to analyze FM signals for target distance information. The degree to which the bats responded with approach phase behavior to a virtual approaching target was similar when they were presented with either a naturally structured artificial FM echo or an artificial FM echo constructed from a series of brief pure tone steps. The ability of the bats to respond to an FM signal structured from a sequence of pure tone elements depended on the number of pure tone steps in the series; the bats required the presentation of tone-step FM signals containing about 83 or greater pure tone elements. Moreover, the duration of the individual tone steps of the tone-step FM signals could not exceed a specific upper limit of about 0.05 ms. Finally, it appears that the bats were able to independently resolve individual tone steps within the tone-step FM signals that were separated by about 450 Hz or more.     

Acute necrotizing cutaneous streptococcal infection following bites or scratch by dog or cat

INTRODUCTION: Domestic animal bites or scratches are quite frequent. Among banal bacteria isolated from infected bites or scratches, group A streptococcus seems to be frequently associated with severe infections. CASE REPORTS: Three cases of acute necrotizing cutaneous streptococcal infections, following cat or dog bite or scratch are reported. Twice, group A streptococcus was isolated from cutaneous swabs. In the third case, previous antibiotic therapy had sterilised bacteriological samples. Diagnosis was ascertained on the basis of clinical presentation and significant antistreptococcal antibodies elevation. Skin necrosis around the inoculation area was observed in the 3 cases. Cicatrisation required an average of two months under appropriate treatment. DISCUSSION: An evolution towards cutaneous necrosis localized to the initially injured area is common to these three cases. This peculiar evolution is worth to be known in order to choose an effective anti streptococcal antibiotherapy whenever domestic animals bites and scratches are to be treated.     

The rattlesnake is not more dangerous than the viper

The article consists of a comparison of the effects of snakebites inflicted by North American rattlesnakes and those of European vipers, based on a review of series of snake bite victims reported in the literature since 1980. The two groups of snakebites were found to manifest close similarity, even regarding the currently low fatality rates. Whereas local reactions seem to be more extensive after rattlesnake bites, circulatory symptoms including severe hypotension appear to be more common after viper bites. It is concluded that the two groups of snakes may be regarded as equally dangerous.     

Characterisation of a novel lyssavirus isolated from Pteropid bats in Australia

A novel lyssavirus isolated from Pteropid bats in Australia (Australian Bat Lyssavirus, ABLV) has been characterised using gene sequence analyses, electron microscopy and a panel of monoclonal antibodies. Electron microscopic examination of Pteropid bat and mouse brain material as well as virus isolated from tissue culture medium, showed the presence of bullet-shaped rhabdovirus particles and structures characteristic of lyssavirus. Analysis using nucleocapsid (N) specific monoclonal antibodies, showed a strong relationship between this new lyssavirus and serotype 1 rabies. The nucleotide sequence of the prototype strain of ABLV was determined from the initiator methionine codon for the nucleocapsid protein (N protein) to the amino terminus of the polymerase gene (L protein), a distance of 5344 nucleotides. Comparisons of the deduced N, phosphoprotein (P), matrix protein (M), and glycoprotein (G) proteins showed that ABLV was more closely related to serotype 1 classic rabies viruses than to other members of the Lyssavirus genus. The percent relatedness of the ABLV proteins when compared to the cognate proteins of PV (Pasteur vaccine strain) rabies was 92, 75, 87 and 75% for the N, P, M and G proteins, respectively. Phylogenetic studies of N protein sequences showed clearly that ABLV is an unrecognised member of the Lyssavirus genus and represents a new genotype, genotype 7.     

Base-compositional biases and the bat problem. III. The questions of microchiropteran monophyly

Using single-copy DNA hybridization, we carried out a whole genome study of 16 bats (from ten families) and five outgroups (two primates and one each dermopteran, scandentian, and marsupial). Three of the bat species represented as many families of Rhinolophoidea, and these always associated with the two representatives of Pteropodidae. All other microchiropterans, however, formed a monophyletic unit displaying interrelationships largely in accord with current opinion. Thus noctilionoids comprised one clade, while vespertilionids, emballonurids, and molossids comprised three others, successively more closely related in that sequence. The unexpected position of rhinolophoids may be due either to the high AT bias they share with pteropodids, or it may be phylogenetically authentic. Reanalysis of the data with varying combinations of the five outgroups does not indicate a rooting problem, and the inclusion of many bat lineages divided at varying levels similarly discounts long branch attraction as an explanation for the pteropodid-rhinolophoid association. If rhinolophoids are indeed specially related to pteropodids, many synapomorphies of Microchiroptera are called into question, not least the unitary evolution of echolocation (although this feature may simply have been lost in pteropodids). Further, a rhinolophoid-pteropodid relationship--if true--has serious implications for the classification of bats. Finally, among the outgroups, an apparent sister-group relation of Dermoptera and Primates suggests that flying lemurs do not represent the ancestors of some or all bats; yet, insofar as gliding of the type implemented in dermopterans is an appropriate model for the evolution of powered mammalian flying, the position of Cynocephalus in our tree indirectly strengthens the argument that true flight could have evolved more than once among bats.     

Computer assisted neurophysiology by a distributed Java program

The mere appearance of a tubular, epithelially-covered, bilateral structure, no matter how minuscule, on the anteroventral nasal septum of tetrapods, is generally called the vomeronasal organ (of Jacobson). However, considering the functionality of this chemosensory structure, the presence of a non-cilated (microvillar) neuroepithelium (and not just any odd type of epithelium) encased in a variously shaped vomeronasal cartilage, along with vomeronasal nerve bundles and above all an accessory olfactory bulb connected to the limbic vomeronasal amygdala, are the absolute essential neurostructural characteristics and anatomic requirement for a functional VNO and the accessory olfactory system in any tetrapod. The distribution of the vomeronasal organ is reported here in two mammalian orders: Chiroptera and Primates. An impressive data pool on the vomeronasal organ of bats is now available, pointing to the fact that at this time bats may be the only group in which this organ system is extremely variable, ranging from total absence (even in the embryo) to spectacular development with numerous intervening stages in different chiropteran species. Of the eighteen bat families, only one family of New World leaf-nosed bats, family Phyllostomidae, exhibits functional vomeronasal organs. The vespertilionid bat Miniopterus, and the mormoopid bat Pteronotus, present exceptions to this rule. Among Primates, very few species have been rigorously studied. As a result, developmental variability of the vomeronasal organ is almost unknown; either the vomeronasal organ is well developed (such as in New World monkeys) or absent (as in Old World monkeys and great apes) in the adult. The concept whether adult humans or embryonic and fetal forms are endowed with this so-called sixth sense, is a controversial one and is under intense study in our laboratory and by others. The general phylogenetic implications based on our cladistic analysis of bats are that the vomeronasal organ complex has evolved several times. Among the prosimians and platyrrhine primates, the organ is well developed, although to a varying degree. Among catarrhine primates, its loss has occurred only once, as it is generally absent in the adult forms.     

Babesia sp. in Colombian bats (Microchiroptera)

Two leaf-chinned bats (Mormoops megalophylla) collected in 1963 in central Colombia were heavily infected with Babesia sp., probably Babesia vesperuginis. Both bats had pronounced splenomegaly. This is the first report of a Babesia sp. infection of a bat in the Americas.     

Transitional cell carcinoma of the ureteral stump 13 years after nephrectomy for benign disease

OBJECTIVE: To estimate the magnitude of the dog bite problem in the US. METHODS: Data on dog bites were gathered as part of a 1994 national telephone survey of 5,238 randomly dialed households. Data were weighted to provide national estimates. RESULTS: The weighted total number of dog bites was 4,494,083 (estimated incidence = 18/1,000 population); of these, 756,701 persons sustained bites necessitating medical attention (incidence rate = 3/1,000). Children had 3.2 times higher medically attended bite rates than adults (6.4/1,000 children v 2/1,000 adults). CONCLUSIONS: More attention and research needs to be devoted to the prevention of dog bites. Potential prevention strategies include: educational programs on canine behavior, especially directed at children; laws for regulating dangerous or vicious dogs; enhanced animal control programs; and educational programs regarding responsible dog ownership and training. Unfortunately, the relative or absolute effectiveness of any of these strategies has not been assessed. Continuing surveillance for dog bites will be needed if we are to better understand how to reduce the incidence of dog bites and evaluate prevention efforts.     

Red-back spider bites to Perth children, 1979-1988

The aim of this study was to describe the pattern of illness caused by red-back spider bites to children in Perth, Western Australia, over a 10 year period, and to compare it with that in adults. The case-notes of 241 (89%) of the 271 children admitted to Princess Margaret Hospital and Fremantle Hospital with suspected red-back spider bite from 1979 to 1988 were available for analysis. A definite bite was defined as a definite bite by a positively identified red-back spider, positive identification of a red-back spider with no definite bite but the later development of typical symptoms or no definite history of red-back spider bite but strong clinical evidence and complete recovery after administration of antivenom. Systemic envenomation was accepted if there were symptoms of vomiting, generalized pain or sweating, or abdominal pain. Sixty-five per cent of children were definitely bitten. As found in previous adult and mixed studies, there was a peak incidence in the warmer months with a male preponderance (68%); 81% of bites were to the extremities and 83% of bites occurred in the daytime. The syndrome produced in children was usually similar to that seen in adults. Twenty-one per cent of children received antivenom, a rate comparable to previous studies in older age groups; however, no child received more than one ampoule. Compared with data extracted from a previously published study at Fremantle Hospital, in which 37% of adults treated with antivenom received more than one ampoule, these findings suggest that contrary to current opinion children may not be at an increased risk of morbidity from latrodectism.     

Rhabdomyolysis in European viper bite

The case of a child who presented with severe rhabdomyolysis associated with renal failure after a viper bite is reported. Rhabdomyolysis is a serious complication resulting from systemic envenomation and is uncommon after viper bites in Europe. It may be due to oedema, myotoxic agents and haemorrhagic factors and may be responsible for two types of potentially fatal complications, i.e. acute renal failure and hyperkalaemia. The present case highlights the need to investigate routinely for rhabdomyolysis after viper bites. Antivenom therapy is recommended as soon as signs of envenomation are present, without waiting for the onset of complications.