Human Rabies Exposure Research Articles

Serological evidence of natural exposure to rabies in rural populations in Gabon.

Rabies is one of the oldest known zoonotic diseases, with dogs being the main reservoir for 99% of the cases of human rabies. However, wild animals may also be rabies vectors. In most cases, contact with a rabid animal results in rabies without pre- or post-exposure prophylaxis, and the disease is nearly always fatal. Nevertheless, a few studies have documented cases of rabies-specific antibodies detection in people with no history of vaccination, suggesting that individuals can be in contact with the virus without developing fatal rabies. To further investigate this possibility of non-lethal human rabies exposure, we carried out a retrospective serological analysis, using both immunoassays (ELISA) and seroneutralization assays (RFFIT), on 430 sera collected between 2005 and 2008 from rural unvaccinated Gabonese populations in the Estuaire and Ogooué-Ivindo provinces. Eleven (11) samples (2.5%) were positive for rabies-specific antibodies using both techniques: 1 in Estuaire and 10 in Ogooué-Ivindo. One of three positive people from the Ogooué-Ivindo province, resampled in early 2023, was still positive for rabies-specific antibodies, suggesting that some degree of immunity can be maintained over many years. Our results also show a marginally significant higher prevalence among hunters. This study demonstrates that rabies circulates actively in Gabon and some unvaccinated individuals living in rural environments can be exposed to the virus and survive, with the development of a significant and specific humoral response that can persist for more than 15 years. This passive seroprevalence survey underlines the need to establish a national surveillance system of rabies in both humans and animals in urban and rural areas, and to enhance access to pre- and post-exposure prophylaxis.

Mathematical model of rabies vaccination in the United States

Mathematical model of rabies vaccination in the United States

Rabies Exposure from Infected Horse Bite in an Urban Setting: A Case Study from Mongolia

Rabies is a highly fatal zoonotic disease that causes an estimated 60,000 human deaths each year, many of which occur in Africa and Asia where the disease is likely underreported. Uncontrolled transmission of rabies presents a major threat to public health in countries such as Mongolia, where 26% of the population lives a pastoralist lifestyle characterized by increased interaction with livestock animals. Here, we report a case of rabies exposure in a six-year-old male after being bitten by a horse in both the head region and the leg. At the suspicion of rabies, post-exposure prophylaxis (PEP) was initiated, with the patient receiving four doses of PEP vaccine as well as a single treatment of rabies immunoglobulin. The horse was later confirmed to be rabies-positive through rapid antigen testing and RT-PCR. Human rabies exposure from horses is unusual within Mongolia, given that historically over 70% of human rabies cases within the country are attributed to dogs, wolves, or foxes. This case further emphasizes the need for more routine vaccination of domestic animals within Mongolia. Additionally, animal bites, even from animals not frequently associated with rabies, should be treated as possible rabies exposure events.

Measuring the impact of an integrated bite case management program on the detection of canine rabies cases in Vietnam.

Dog-mediated rabies is enzootic in Vietnam, resulting in at least 70 reported human deaths and 500,000 human rabies exposures annually. In 2016, an integrated bite cases management (IBCM) based surveillance program was developed to improve knowledge of the dog-mediated rabies burden in Phu Tho Province of Vietnam. The Vietnam Animal Rabies Surveillance Program (VARSP) was established in four stages: (1) Laboratory development, (2) Training of community One Health workers, (3) Paper-based-reporting (VARSP 1.0), and (4) Electronic case reporting (VARSP 2.0). Investigation and diagnostic data collected from March 2016 to December 2019 were compared with historical records of animal rabies cases dating back to January 2012. A risk analysis was conducted to evaluate the probability of a rabies exposure resulting in death after a dog bite, based on data collected over the course of an IBCM investigation. Prior to the implementation of VARSP, between 2012 and 2015, there was an average of one rabies investigation per year, resulting in two confirmed and two probable animal rabies cases. During the 46 months that VARSP was operational (2016 - 2019), 1048 animal investigations were conducted, which identified 79 (8%) laboratory-confirmed rabies cases and 233 (22%) clinically-confirmed(probable) cases. VARSP produced a 78-fold increase in annual animal rabies case detection (one cases detected per year pre-VARSP vs 78 cases per year under VARSP). The risk of succumbing to rabies for bite victims of apparently healthy dogs available for home quarantine, was three deaths for every 10,000 untreated exposures. A pilot IBCM model used in Phu Tho Province showed promising results for improving rabies surveillance, with a 26-fold increase in annual case detection after implementation of a One Health model. The risk for a person bitten by an apparently healthy dog to develop rabies in the absence of rabies PEP was very low, which supports the WHO recommendations to delay PEP for this category of bite victims, when trained animal assessors are available and routinely communicate with the medical sector. Recent adoption of an electronic IBCM system is likely to expedite adoption of VARSP 2.0 to other Provinces and improve accuracy of field decisions and data collection.

Reservoir dynamics of rabies in south-east Tanzania and the roles of cross-species transmission and domestic dog vaccination.

Understanding the role of different species in the transmission of multi-host pathogens, such as rabies virus, is vital for effective control strategies. Across most of sub-Saharan Africa domestic dogs Canis familiaris are considered the reservoir for rabies, but the role of wildlife has been long debated. Here we explore the multi-host transmission dynamics of rabies across south-east Tanzania.Between January 2011 and July 2019, data on probable rabies cases were collected in the regions of Lindi and Mtwara. Hospital records of animal-bite patients presenting to healthcare facilities were used as sentinels for animal contact tracing. The timing, location and species of probable rabid animals were used to reconstruct transmission trees to infer who infected whom and the relative frequencies of within- and between-species transmission.During the study, 688 probable human rabies exposures were identified, resulting in 47 deaths. Of these exposures, 389 were from domestic dogs (56.5%) and 262 from jackals (38.1%). Over the same period, 549 probable animal rabies cases were traced: 303 in domestic dogs (55.2%) and 221 in jackals (40.3%), with the remainder in domestic cats and other wildlife species.Although dog-to-dog transmission was most commonly inferred (40.5% of transmission events), a third of inferred events involved wildlife-to-wildlife transmission (32.6%), and evidence suggested some sustained transmission chains within jackal populations.A steady decline in probable rabies cases in both humans and animals coincided with the implementation of widespread domestic dog vaccination during the first 6 years of the study. Following the lapse of this program, dog rabies cases began to increase in one of the northernmost districts. Synthesis and applications. In south-east Tanzania, despite a relatively high incidence of rabies in wildlife and evidence of wildlife-to-wildlife transmission, domestic dogs remain essential to the reservoir of infection. Continued dog vaccination alongside improved surveillance would allow a fuller understanding of the role of wildlife in maintaining transmission in this area. Nonetheless, dog vaccination clearly suppressed rabies in both domestic dog and wildlife populations, reducing both public health and conservation risks and, if sustained, has potential to eliminate rabies from this region.

The urgency of resuming disrupted dog rabies vaccination campaigns: a modeling and cost-effectiveness analysis

Dog vaccination is a cost-effective approach to preventing human rabies deaths. In Haiti, the last nation-wide dog vaccination campaign occurred in 2018. We estimated the number of human lives that could be saved by resuming dog vaccination in 2021 compared to 2022 and compared the cost-effectiveness of these two scenarios. We modified a previously published rabies transmission and economic model to estimate trends in dog and human rabies cases in Haiti from 2005 to 2025, with varying assumptions about when dog vaccinations resume. We compared model outputs to surveillance data on human rabies deaths from 2005 to 2020 and animal rabies cases from 2018 to 2020. Model predictions and surveillance data both suggest a 5- to 8-fold increase in animal rabies cases occurred in Haiti’s capital city between Fall 2019 and Fall 2020. Restarting dog vaccination in Haiti in 2021 compared to 2022 could save 285 human lives and prevent 6541 human rabies exposures over a five-year period. It may also decrease program costs due to reduced need for human post-exposure prophylaxis. These results show that interruptions in dog vaccination campaigns before elimination is achieved can lead to significant human rabies epidemics if not promptly resumed.

Human rabies exposure outbreak investigation in Tembaro district, Ethiopia, 2018

Human rabies exposure outbreak investigation in Tembaro district, Ethiopia, 2018

Human rabies exposure outbreak investigation in Tembaro district, Ethiopia, 2018

Human rabies exposure outbreak investigation in Tembaro district, Ethiopia, 2018

Risk Factors and Spatio-Temporal Patterns of Human Rabies Exposure in Northwestern Tigray, Ethiopia

Background:Rabies is a neglected tropical disease, which is economically important with great public health concerns in developing countries including Ethiopia. Epidemiological information can play an important role in the control and prevention of rabies, though little is known about the status of the disease in many settings of Ethiopia. The present study aimed to investigate the risk factors and spatio-temporal patterns of human rabies exposure in Northwestern Tigray, Ethiopia.Methods:A prospective study was conducted from 01 January 2016 to 31 December 2016 (lapsed for one year) at Suhul general hospital, Northern Ethiopia. Data of human rabies exposure cases were collected using a pretested questionnaire that was prepared for individuals dog bite victims. Moreover, GPS coordinate of each exposure site was collected for spatio-temporal analysis using hand-held Garmin 64 GPS apparatus. Later, cluster of human rabies exposures were identified using Getis-Ord Gi* statistics.Results:In total, 368 human rabies exposure cases were collected during the study year. Age group of 5 to 14 years old were highly exposed (43.2%; 95% CI, 38.2–48.3). Greater number of human rabies exposures was registered in males (63%; 95% CI, 58.0–67.8) than females (37%; 95% CI, 32.1–42.0). Residents of rural (85.6%; 95% CI, 81.6–88.8) areas were at greater risk to rabies than urban residents (14.4%; 95% CI, 11.2–18.4). Higher proportion of human rabies exposures were caused by unprovoked (96.5%; 95% CI, 94.0–98.0) and unvaccinated (85.9%; 95% CI, 81.9–89.1) dogs. All rabies exposures were exclusively caused by dog bites and the majority of them (80.4%; 95% CI, 76.0–84.2) were caused by stray dogs. Results of spatio-temporal analysis showed that Asgede Tsimbla, Endaselassie and Laelay Adiyabo districts experienced the highest burden of rabies exposure; identified as hot spots. Strong peaks of human rabies exposure occurred between March and July months.Conclusion:The present study provided basic epidemiological information on the potential risk factors associated with human rabies exposure. Moreover, our findings provided basis for understanding the spatio-temporal patterns of human rabies in Northwestern Tigray districts for the first time.

Impact of One-Health framework on vaccination cost-effectiveness: A case study of rabies in Ethiopia

Impact of One-Health framework on vaccination cost-effectiveness: A case study of rabies in Ethiopia

Vital Signs: Trends in Human Rabies Deaths and Exposures - United States, 1938-2018.

IntroductionEach year, rabies causes approximately 59,000 deaths worldwide, including approximately two deaths in the United States. Before 1960, dogs were a common reservoir of rabies in the United States; however, increasingly, species of wildlife (e.g., bats, raccoons) are the main reservoirs. This report characterizes human rabies deaths, summarizes trends in rabies mortality, and highlights current rabies risks in the United States.MethodsRabies trends in the United States during 1938–2018 were analyzed using national rabies surveillance data. Data from the Healthcare Cost and Utilization Project for 2006–2014 were used to estimate the number of postexposure prophylaxis (PEP) visits per 100,000 persons during 2017–2018. The Centers for Medicare & Medicaid Services’ average sales price data were used to estimate PEP costs.ResultsFrom 1960 to 2018, a total of 125 human rabies cases were reported in the United States; 36 (28%) were attributed to dog bites during international travel. Among the 89 infections acquired in the United States, 62 (70%) were attributed to bats. In 2018, approximately 55,000 persons sought PEP after contact with a potentially rabid animal.Conclusions and CommentsIn the United States, wildlife rabies, especially in bats, continues to pose a risk to humans. Travelers also might be exposed to canine rabies in countries where the disease is still present; increased awareness of rabies while traveling abroad is needed. Vaccinating pets, avoiding contact with wildlife, and seeking medical care if one is bitten or scratched by an animal are the most effective ways to prevent rabies. Understanding the need for timely administration of PEP to prevent death is critical.

Incidence of human rabies virus exposure in northwestern Amhara, Ethiopia

BackgroundClinical Rabies is a widely distributed almost 100% fatal viral zoonotic disease. Most human rabies cases occur in developing countries, especially in Asia and Africa. It can be prevented by immunization, post exposure prophylaxis. Ethiopia is assumed to be among African countries with high incidence of human rabies exposure cases. However, there is limited documented data on the incidence of human rabies exposure in the study area in particular and in Ethiopia in general. Thus, this study aimed to determine the Incidence of Human Rabies Virus exposure in Northwestern Amhara, Ethiopia.MethodsRetrospective cross-sectional study was conducted during August and September, 2017. The study was conducted at Addis Alem Hospital, a district level hospital in Bahir Dar. Data on human rabies exposure cases registered from September 1, 2015 to August 31, 2017 were collected from anti-rabies post exposure prophylaxis registration log book. Data was collected using a structured data collection questionnaire developed for this purpose. Descriptive statistics was used to describe relevant variables.The resultsA total of 924 human rabies exposure cases was recorded. The overall human rabies incidence per 100, 000 population was 6.5 in 2015 and 7.5 in 2016. Males (55.2%, 510/924) and children of age less than fifteen (46.3%, 428/924) were most affected groups. The majority of human rabies exposure cases (71.9%, 664/924) were from rural settings. Dogs were the principal sources of exposure (96.3%) followed by cat (1.5%) and donkey (1.3%). High incidence rate of rabies exposure was reported during spring (360, 39%) and summer (244, 26.4%) seasons. There was significant difference between rural and urban exposure cases (p = 0.001) in respect to the time of arrival to the hospital.ConclusionTaking these into account, a significant proportion of the population was exposed to rabies virus during the study years. There was high human rabies exposure rate in children and in the rural community.This shows the need for organizing preventive and control strategies and to build community awareness.

Improving systematic rabies surveillance in Cameroon: A pilot initiative and results for 2014-2016.

Canine rabies is endemic in Cameroon, but human rabies exposures and cases are likely underreported because of inadequate surveillance. In 2014, the surveillance network in the West region of Cameroon was reinforced by introducing a new anti-rabies center, a framework for data collection and evaluation, provisions for sample collecting and laboratory confirmation, and training for health professionals. The objective of this observational cohort study was to describe the incidence and characteristics of reported exposures and human and animal rabies cases following this reinforcement of the existing rabies surveillance system. The surveillance network consisted of local, regional, and national health and veterinary authorities in 11 of the 20 West region districts, and was completely integrated within the existing national rabies surveillance network. Animal exposures and suspected rabies exposures, the suspected rabid animals involved, and laboratory confirmation of human and animal rabies cases were recorded in a centralized information database. Between January 2014 and June 2016, the network recorded 1340 animal exposure cases for an overall incidence rate of 38.2 animal exposures per 100,000 people, four confirmed rabies-positive animals, and one confirmed human rabies case out of four clinically suspected cases. In contrast, 62 animal exposures and an overall incidence rate of 6.1 exposures per 100,000 people were reported for the West region districts not participating in the reinforced surveillance. Of the 925 animal exposure victims for whom a detailed case report form was completed, 703 were considered to be at risk of rabies and only 428 (61%) of these received any post-exposure prophylaxis in the form of rabies vaccine. Obstacles encountered within the network included low rates of animal sample submission and animal follow-up by veterinarians. Reinforced rabies surveillance in the West region of Cameroon has provided the most accurate estimate of the region’s disease and exposure burdens to date, and indicates that animal exposures are substantially underreported. The reinforced network also signaled that greater access to post-exposure prophylaxis is needed. Integration of regions not covered by the surveillance network and efforts to improve engagement of veterinary services will be needed to reveal the true burden of rabies in Cameroon.

Vaccination of dogs in an African city interrupts rabies transmission and reduces human exposure.

Despite the existence of effective rabies vaccines for dogs, dog-transmitted human rabies persists and has reemerged in Africa. Two consecutive dog vaccination campaigns took place in Chad in 2012 and 2013 (coverage of 71% in both years) in the capital city of N'Djaména, as previously published. We developed a deterministic model of dog-human rabies transmission fitted to weekly incidence data of rabid dogs and exposed human cases in N'Djaména. Our analysis showed that the effective reproductive number, that is, the number of new dogs infected by a rabid dog, fell to below one through November 2014. The modeled incidence of human rabies exposure fell to less than one person per million people per year. A phylodynamic estimation of the effective reproductive number from 29 canine rabies virus genetic sequences of the viral N-protein confirmed the results of the deterministic transmission model, implying that rabies transmission between dogs was interrupted for 9 months. However, new dog rabies cases appeared earlier than the transmission and phylodynamic models predicted. This may have been due to the continuous movement of rabies-exposed dogs into N'Djaména from outside the city. Our results show that canine rabies transmission to humans can be interrupted in an African city with currently available dog rabies vaccines, provided that the vaccination area includes larger adjacent regions, and local communities are informed and engaged.

Recognizing the Role of Skunks in Human and Animal Rabies Exposures in the Southwest.

Rabies is arguably the most important viral zoonotic disease worldwide with an estimated 55,000 human deaths each year. Globally, dogs are the primary animals affected. In the United States, especially on the East Coast, raccoons and bats are the primary reservoir. However, in the southwestern United States, skunk and bat rabies play a large role. We describe the epidemiology and environmental risk factors associated with rabies in the US Southwest using exposure data for 2004-2012 from one Arizona county as a case study. Unlike other parts of the country, here bats and skunks are the most commonly collected positive animals (62% and 32%, respectively). Even though most of the positive animals were bats, human and domestic animal exposures were primarily a result of skunk interactions (58% and 50%, respectively). Consequently, the majority of exposures occur early in the year, January and February, when the majority of skunk pickups also occur. Using public health surveillance data, our study highlights the importance of recognizing the role of skunks in human and animal exposures in the southwestern United States. Consistent with a "One Health" approach, our data show how wildlife and domestic animal and human exposures are associated and informative to one another.

Incidence of human rabies exposure and associated factors at the Gondar Health Center, Ethiopia: a three-year retrospective study.

BackgroundRabies is one of the oldest known and most feared human diseases. Epidemiological studies provide basic information about the burden of the disease and underline the importance of prevention and control interventions. However, there have been limited studies conducted regarding the incidence of rabies and associated factors in Ethiopia, in general, and in this study area, in particular. Therefore, the aim of this study was to assess the incidence of human rabies exposure and associated factors at the Gondar Health Center, Ethiopia.MethodsA retrospective cross-sectional study was conducted at the Gondar Health Center where post-exposure prophylaxis (PEP) for rabies was available for the whole population in the North Gondar Zone catchment area. Data of human rabies exposure cases between 2011 and 2013 were collected from the rabies PEP registration book using data abstraction sheets. The data was entered and analyzed using SPSS version 16 statistical software.ResultA total of 261 cases of human rabies exposure were reported to the Gondar Health Center from 2011 to 2013. The sex and age specific distribution showed that the majority of these cases were among males (142/226, 62.8%) and children under 15 years of age (87/226, 38.5%). A predominant number of cases were observed in individuals from rural areas (161/220, 73.2%), and during fall and winter seasons (67/222, 30.18%). A significant number of people exposed to rabies (23.2%) came to the health center for PEP two or more weeks after the injury. The incidence of human rabies exposure cases was 4.6, 2.61, and 1.27 per 100, 000 population in 2011, 2012, and 2013, respectively. Being male and living in an urban setting were found to be risk factors for human rabies exposure in 2011.ConclusionA significant number of human rabies exposure cases were reported to the Gondar Health Center. Being male and living in an urban setting were found to be associated with rabies exposure. A community-based follow-up study is recommended to more accurately estimate the incidence of human rabies exposure.Electronic supplementary materialThe online version of this article (doi:10.1186/2049-9957-4-3) contains supplementary material, which is available to authorized users.

Human Rabies Prevention (Comment From a Canine‐Rabies‐Endemic Region)

is a summaryof current human rabies exposure managementfrom the perspective of the developed world wherebiologicals are available, public health staff handle mostrabies-exposed subjects and mostly for free to thepatients. The situation is different in rabies-endemicregions where rabies vaccines and immunoglobulinsare often not available or affordable to the averagecitizen. The fear of rabies, the adverse side effectsfrom old brain-tissue-derived vaccines, the lengthypostexposure treatment schedules, and the dreadfuldeath are still remembered. They discourage somepatients from seeking professional help. This isparticularly true in countries where World HealthOrganization (WHO)-level treatment is only availableat private hospitals, which most victims cannot afford.The article by Sibunruang and colleagues

The Beneficial Auxiliary Role of Poison Information Centers: Stewardly Use of Rabies Post-Exposure Prophylaxis in a Time of Shortage

Background: During the one-year period from May 2008 to May 2009, a nationwide shortage developed which rabies vaccine was not being produced by the manufacturers. In order to manage existing supply, a protocol was established wherein an authorization was required from the regional poison center before vaccine could be administered to a patient. Methods: The Georgia Poison Center internal database was accessed for information pertaining to rabies exposure calls for the time of the restriction, as well as the years before and after. Results were examined for the total number of human rabies exposure calls received by the poison center, as well as the number of cases in which PEP was recommended. Results: During the restriction period, the number of rabies-related calls increased, while the percentage of cases in which PEP was recommended, remained consistent. The year following the restriction, the number of rabies related calls remained elevated. Conclusion: Our Regional Poison Center was able to make a positive impact by reducing unnecessary use of PEP in a time of shortage and thereby ensuring that all patients who needed the vaccine were able to receive it. This further shows the potential capacity of the poison information centers to optimize healthcare services.

Potential cost savings with terrestrial rabies control.

BackgroundThe cost-benefit of raccoon rabies control strategies such as oral rabies vaccination (ORV) are under evaluation. As an initial quantification of the potential cost savings for a control program, the collection of selected rabies cost data was pilot tested for five counties in New York State (NYS) in a three-year period.MethodsRabies costs reported to NYS from the study counties were computerized and linked to a human rabies exposure database. Consolidated costs by county and year were averaged and compared.ResultsReported rabies-associated costs for all rabies variants totalled $2.1 million, for human rabies postexposure prophylaxes (PEP) (90.9%), animal specimen preparation/shipment to laboratory (4.7%), and pet vaccination clinics (4.4%). The proportion that may be attributed to raccoon rabies control was 37% ($784,529). Average costs associated with the raccoon variant varied across counties from $440 to $1,885 per PEP, $14 to $44 per specimen, and $0.33 to $15 per pet vaccinated.ConclusionRabies costs vary widely by county in New York State, and were associated with human population size and methods used by counties to estimate costs. Rabies cost variability must be considered in developing estimates of possible ORV-related cost savings. Costs of PEPs and specimen preparation/shipments, as well as the costs of pet vaccination provided by this study may be valuable for development of more realistic scenarios in economic modelling of ORV costs versus benefits.

DIRECT AND INDIRECT COSTS OF RABIES EXPOSURE: A RETROSPECTIVE STUDY IN SOUTHERN CALIFORNIA (1998–2002)

The direct and indirect costs of suspected human rabies exposure were estimated for San Luis Obispo and Santa Barbara counties, California, USA. Clinic, hospital, and county public health records (1998-2002) were examined to determine direct costs for postexposure prophylaxis (PEP), and 55 (41%) former patients were contacted to voluntarily provide estimates of their indirect costs associated with receiving PEP. Additional costs due to public health and animal control personnel responses to rabid animals were collected, including diagnostic testing and wages. The mean total cost of a suspected human rabies exposure was $3,688, the direct costs per case were $2,564, and the indirect costs were $1,124 of that total. About one third of the total cost for suspected human rabies exposure was attributed to indirect costs (e.g., lost wages, transportation, and day-care fees), most of which were not reimbursable to the patient.