Rabies in Southeast Asia: a systematic review of its incidence, risk factors and mortality

Communication channel preference for raising rabies awareness among dog owners in Thailand: A nationwide study

Rabies is a severe zoonotic disease with potentially fatal consequences. Effective communication channels are crucial for disseminating key rabies prevention and control messages to target populations. This study examined how dog owners' demographic factors influenced communication channels in Thailand. We distributed a questionnaire survey to retrieve general demographic data of participants and the ranks of their communication channels. We used the mean ranking score to assess the most accessible and commonly used platforms. Univariate and multiple logistic regression methods were used to determine the association between each demographic feature and the preference for communication. In total, 476 participants were involved across all regions of Thailand. Village health volunteers represented the most selected channel, as identified by the mean ranking (3.32), followed by public loudspeaker (3.30) and television (2.93). Age, occupation, region, and cat ownership significantly influenced how people chose the channels. Moreover, farmers likely received information from various sources, and elderly individuals generally preferred to receive information about rabies from administrative authorities, such as village heads. These results can benefit policymakers aiming to enhance communication strategies in public health. This study enhances rabies risk communication and aligns with global health initiatives to eliminate dog-mediated rabies by 2030.

Long-term spatio-temporal trends in global rabies burden and its association with animal rabies vaccination during 1990-2019

Rabies remains a major public health issue. Yet, trends in rabies burden associated with age, period, and cohort effects remain unknown, and the association between animal rabies vaccination and rabies burden is unclear. We aimed to understand the long-term spatio-temporal trends in global rabies burden, the impacts of age, periods, and birth cohorts, and the association between animal rabies vaccination and burden. Rabies burden data were extracted from Global Burden of Disease Study 2019. We used joinpoint regression to assess temporal trends in rabies burden and age-period-cohort model to evaluate age, period, and cohort effects on rabies incidence and mortality. Animal rabies vaccination data were obtained from World Animal Health Information System. The association between the ratio of vaccinated animals and age-standardized incidence rate was explored. From 1990 to 2019, the global rabies incident cases, deaths, and disability-adjusted life years (DALYs) decreased by 43.12%, 47.20%, and 54.59%, respectively. Age-standardized rates of incidence, mortality, and DALYs declined in all socio-demographic index (SDI) regions, yet consistently remained the highest in low SDI region. The highest rabies incidence rate and mortality rate were observed in children aged 0-9 years. Population living during 1990-1994 had the highest rabies incidence and mortality risks. Countries and territories with high rabies age-standardized incidence rate generally had low ratios of vaccinated animals. Globally, rabies burden decreased over past 30 years, yet disparities in rabies burden regarding gender, age, period, cohort and SDI region existed. Targeted strategies are needed, especially in low SDI region and among children aged 0-9 years.

Incidence, risk factors, and control of Rabies in Ethiopia: A systematic review and meta-analysis

BACKGROUND

Globally, rabies is found in several geographical areas, with tens of thousands of deaths annually, mainly in developing countries. However, though Ethiopia is highly endemic for rabies, the overall risk of rabies has not yet been estimated. Hence, this systematic review and meta-analysis aimed at estimating a pooled incidence rate of human exposure to suspected rabid animals as well as the incidence rates of rabies in humans and other domestic animals.

METHODS

Published articles search was systematically performed through PubMed, Scopus, Embase, and Web of Science databases to identify the available studies on rabies until October 2023. The Joanna Brigg's Institute (JBI) critical appraisal checklists were used for assessing the quality of the studies. The PRISMA 2020 guideline was followed. A qualitative synthesis was made describing the characteristics of the included studies. The quantitative synthesis was performed with a random effects model using Comprehensive Meta-Analysis (CMA) version 3.0 software. The Q statistic quantified by I2 was used to check for heterogeneity among the included studies. To explain the source of heterogeneity, subgroup analysis was performed. Egger's regression test was used to evaluate publication biases. This study is registered with PROSPERO, CRD42023468791.

RESULTS

For this study, a total of 439 articles were retrieved; of which fifteen studies were included in the final review. The annual pooled incidence rate of human exposure to suspected rabid animals was 33.65 (95% CI: 31.82 to 35.49) per 100,000 humans. The suspected rabies deaths in humans were also estimated to be 4.57 (95% CI: 2.93 to 6.21) per one million humans annually. In both cases, considerable heterogeneities were presented across the included studies, and obvious publication biases were detected using Egger's regression test. Among animals, the highest combined estimate per 100,000 population was recorded in dogs, 120.99 (95% CI: 46.29 to 195.69), followed by equines and cattle, with pooled incidence rates of 19.57 (95% CI: -1.85 to 40.98) and 18.08 (95% CI: 1 to 35.15), respectively. It was also described that human exposure to rabid animals and human rabies deaths were more common among children.

CONCLUSIONS

The current study showed a high pooled incidence rate of human exposure to rabid animals. Significant overall incidence rates of rabies in humans and animals were also indicated. Therefore, strengthening intersectoral and transdisciplinary collaborations through one health approach are key components for rabies prevention and control.

An Implementation Science Framework to Understand Low Coverage in Mass Dog Rabies Vaccination

Background

Dog-mediated human rabies has been greatly reduced in the Americas and eliminated from most high-income countries. However, many countries in Africa, Asia, and parts of Latin America are still struggling with this gruesome disease. Mass dog vaccination, a One Health strategy, is the primary approach for elimination. However, achieving and sustaining appropriate vaccination coverage in endemic areas remains a challenge. Our objective was to apply the Consolidated Framework for Implementation Research (CFIR) in Arequipa, Peru as a guiding tool to understand the barriers faced by different stakeholders.

Methods

Seven focus groups with 56 participants were conducted to capture community perspectives on rabies and vaccination. A workshop was conducted with two groups of public health personnel (n= 69): mass dog vaccination campaign (MDVC) implementers and authorities, in charge of dog rabies control. With these stakeholders we explored factors contributing to the decrease in MDVC post COVID-19. We used the CFIR approach to understand barriers within five different domains: innovation, outer setting, inner setting, individuals, and implementation.

Findings

Barriers within the community included insufficient communication, a short vaccination schedule, and fragmented collaboration between system coordinators. At the individual level, a decreased perception of rabies risk occurred as both people and their dogs spent more time indoors due to the COVID-19 pandemic (in urban areas). Dog vaccination was deprioritized compared to COVID protection, with individuals focusing on their own vaccinations and avoiding crowded spaces. In peri-urban areas, longer work hours due to the pandemic's financial impact left less time for dog vaccinations on weekends. Participants reported confusion caused by private veterinarians, who claimed that government-subsidized vaccines were of poor quality. Among implementers and authorities, the main barriers included insufficient MDVC materials and equipment, unclear responsibilities, and a lack of time to evaluate the campaign after activities. Importantly, financial constraints and fragmented commitment from higher-level institutions posed challenges for proper planning and implementation.

Conclusions

We identified barriers and co-designed strategies to improve MDVC participation including strengthening municipal alliances, virtual and physical publicity for events within districts, adequate training for vaccinators, reinforcing vaccinators to remain in fixed spots, and expanding vaccination campaign hours.

Rabies epidemiology in Malaysia (2015-2023): A cross-sectional insights and strategies for control

BACKGROUND

Malaysia currently faces significant challenges in controlling the spread of dog-mediated human rabies, as evidenced by recurrent outbreaks in newly affected areas and increasing human fatalities.

MATERIALS AND METHODS

A cross-sectional study was conducted to analyse surveillance data from 2015 to 2023 to examine the epidemiological characteristics of rabies in Malaysia. Data from multiple sources were used, and descriptive statistics, incidence rates, and reproductive numbers were calculated. QGIS software was used to map the distribution of rabies cases, and statistical methods were employed to evaluate associations between rabies incidence, vaccination coverage, and risk factors. We further explored the effectiveness of vaccination campaigns and public health interventions in reducing rabies transmission.

RESULTS

Our findings revealed 995 confirmed rabies cases in animals. Sarawak reported the highest proportion of rabies cases at 97.99 %, showing a significant correlation between location and rabies cases (p < .001). Dogs comprised 89.35 % of confirmed cases, while the average annual vaccination rate was only 16.66 %, far below the 59.05 % needed for herd immunity. Moreover, human rabies cases reported in Sarawak had an alarmingly high fatality rate of 90.28 %, highlighting the urgent need for improved public health measures and surveillance.

CONCLUSION

This research provides critical insights for policymakers and health officials to improve rabies control strategies in Malaysia.

Combatting rabies outbreaks in Vietnam: High time to enforce restrictions on dog meat farming, a key source of transmission

In Vietnam, farming dogs for meat is not illegal but is increasingly marginalized as dog meat consumption comes under heightened social scrutiny. This loosely regulated practice likely increases the risk of rabies transmission to humans. At a time when human-wildlife conflict has become a major discussion point for global health, stray dogs escaping or being deliberately released from dog farms is a cause for serious concern. The first half of 2024 saw a significant spike in the incidence of human rabies cases, occurring in not just rural hot spots but also urban conurbations. Bites from rabid feral dogs are the primary source of infection, the distribution of which often clusters in the vicinity of battery farms or slaughterhouses that have recently downscaled or closed their business. Addressing this risk requires pursuing a One Health strategy that focuses on catching and euthanizing rabid dogs, vaccinating healthy dogs, implementing safety measures during dog slaughtering, and regulating dog meat trade. By robust enforcement of this comprehensive plan, it is hoped to prevent rabies outbreaks and protect public health. Hanoi is already taking the lead in introducing measures to avert a rabies crisis in the Vietnamese capital.

Levonorgestrel enhanced Toxoplasma gondii infection risk via progesterone receptor upregulation

The numerous stray cats and dogs worldwide pose a huge burden on local governments, keeping residents safe and healthy, and maintaining clean cities with good traffic situations. To effectively control the populations of these stray animals, while considering animal welfare, researchers have suggested the use of levonorgestrel (LNG) as a contraceptive method. However, the potential side effects of LNG on these animals need to be evaluated before widespread application. Since dogs and cats play important roles in the transmission of Toxoplasma gondii as intermediate and definitive hosts, respectively, it is critical to assess the safety of LNG from the perspective of its effect on Toxoplasma susceptibility. In this study, the susceptibility of mice to T. gondii infection was investigated in vivo and in vitro with the presence of LNG. As a result, LNG increased the risk of infection, which was probably associated with the downregulation of IFN-γ levels, but not with the alteration of host sex hormone levels. Concurrently, the presence of LNG enhanced the expression of its ligand, the progesterone receptor (PGR), on the host cells. The promotional effect of LNG on T. gondii infection was attenuated when the PGR gene was knocked down. This investigation represents the inaugural study of LNG's side effects on T. gondii infection in mice, underscoring the significance of choosing or developing suitable contraceptive drugs for stray animals.

Randomized Controlled Trial of the Immunogenicity and Safety of a Serum-Free Purified Vero Rabies Vaccine (PVRV-NG2) Using a Simulated Postexposure Zagreb Regimen With Human Rabies Immunoglobulin in Adults in Thailand

Background

A serum-free, highly purified Vero rabies vaccine-next generation (PVRV-NG2) is under development. We conducted a phase III trial to describe the safety and immunogenicity profile of PVRV-NG2 compared with those of licensed purified Vero rabies vaccine (PVRV) in a simulated rabies postexposure prophylaxis (PEP) Zagreb regimen in Thailand.

Methods

Healthy adults aged ≥18 years (n = 201) were randomized in a 2:1 ratio to receive PVRV-NG2 or PVRV in a rabies PEP Zagreb (days 0, 7, 21 [2-1-1]) regimen, with concomitant human rabies immunoglobulin (HRIG) at day 0. Immunogenicity end points included the proportion of participants with rabies virus-neutralizing antibody (RVNA) titers ≥0.5 IU/mL at days 0, 14, and 35. Safety outcomes were also assessed.

Results

A total of 199 participants completed the study (PVRV-NG2 n = 133, PVRV n = 66). In the PVRV-NG2 group and PVRV group, respectively, 91.0% (95% CI, 84.1%-95.6%) and 94.6% (95% CI, 85.1%-98.9%) had RVNA titers ≥0.5 IU/mL at day 14, increasing to 100% (95% CI, 96.8%-100%) and 100% (95% CI, 93.5%-100%) by day 35. The vaccines had similar safety profiles, and there were no safety concerns.

Conclusions

PVRV-NG2 showed acceptable safety and immunogenicity profiles when co-administered with HRIG in a simulated PEP Zagreb regimen in healthy adults in Thailand.

Machine learning to improve the understanding of rabies epidemiology in low surveillance settings

In low and middle-income countries, a large proportion of animal rabies investigations end without a conclusive diagnosis leading to epidemiologic interpretations informed by clinical, rather than laboratory data. We compared Extreme Gradient Boosting (XGB) with Logistic Regression (LR) for their ability to estimate the probability of rabies in animals investigated as part of an Integrated Bite Case Management program (IBCM). To balance our training data, we used Random Oversampling (ROS) and Synthetic Minority Oversampling Technique. We developed a risk stratification framework based on predicted rabies probabilities. XGB performed better at predicting rabies cases than LR. Oversampling strategies enhanced the model sensitivity making them the preferred technique to predict rare events like rabies in a biting animal. XGB-ROS classified most of the confirmed rabies cases and only a small proportion of non-cases as either high (confirmed cases = 85.2%, non-cases = 0.01%) or moderate (confirmed cases = 8.4%, non-cases = 4.0%) risk. Model-based risk stratification led to a 3.2-fold increase in epidemiologically useful data compared to a routine surveillance strategy using IBCM case definitions. Our study demonstrates the application of machine learning to strengthen zoonotic disease surveillance under resource-limited settings.

Factors associated with the spatiotemporal distribution of dog rabies in Tunisia

Despite continuous efforts of veterinary services to control rabies in dogs since 1982, rabies remains a cause of death in Tunisia, with more than five reported human cases in 2022. As little is known on the determinants of transmission of rabies in dogs, better understand which factors contribute to its spatial heterogeneity in Tunisia is critical for developing bespoke mitigation activities. In this context, we developed Bayesian Poisson mixed-effect spatio-temporal model upon all cases of rabid dogs reported in each delegation during the period from 2019 to 2021. The best fitting model highlighted the association between the risk of rabies and the mean average monthly temperature, the density of markets and the density of dogs in delegations. Interestingly, no relationship was found between intensity of vaccination in dogs and the risk of rabies. Our results provided insights into the spatio-temporal dynamics of dog rabies transmission and highlighted specific geographic locations where the risk of infection was high despite correction for associated explanatory variables. Such an improved understanding represent key information to design bespoke, cost-efficient, rabies prevention and control strategies to support veterinary services activities and policymaking.

Myocardial infarction with nonobstructive coronaries (MINOCA) following rabies postexposure prophylaxis: A case report

Key Clinical Message

This case underscores the importance of considering myocardial infarction with nonobstructive coronary arteries (MINOCA) in patients experiencing acute chest pain following rabies vaccination, emphasizing the need for heightened awareness and further research into the association between MINOCA and Rabies vaccination.

Abstract

Rabies is a vaccine-preventable deadly viral disease prevalent in Asia and Africa that causes thousands of deaths annually. Rabies pre (PrEP) and postexposure prophylaxis (PEP) is highly effective in annulling rabies-associated deaths. The adverse reactions following rabies vaccination are typically mild. Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a rare condition, and its association with rabies vaccination is unprecedented. We present a case of a 43-year-old male with MINOCA following Rabies PEP. A 43-year-old male, nonsmoker and nonalcoholic, presented to the ER with complaints of acute onset left sided chest pain following the completion of the third dose of intradermal rabies vaccine, whose clinical features, ECG changes and lab reports were suggestive of acute presentation of inferior wall MI. Coronary angiography was performed, which however revealed normal coronaries with only slow flow being noted in the left anterior descending (LAD) artery. Echocardiography later showed a normal study with no other relevant diagnosis unveiled on further investigations. Hence a diagnosis of vaccine-induced MINOCA was made. Treatment included antiplatelet therapy, statins, and beta-blockers. MINOCA following rabies vaccination is an unprecedented finding. The clear etiology behind this couldn't be ascertained. The patient's treatment was conventional, emphasizing the need for further research and clinical trials in MINOCA diagnosis and management. This case highlights the need for clinicians to consider MINOCA in patients with acute chest pain post-rabies vaccination. Further research is essential to unravel the association between MINOCA and rabies vaccination, paving the way for optimal management strategies.

Time-series analysis of meteorological factors and emergency department visits due to dog/cat bites in Jinshan area, China

Background

Meteorological factors play an important role in human health. Clarifying the occurrence of dog and cat bites (DCBs) under different meteorological conditions can provide key insights into the prevention of DCBs. Therefore, the objective of the study was to explore the relationship between meteorological factors and DCBs and to provide caution to avoid the incidents that may occur by DCBs.

Methods

In this study, data on meteorological factors and cases of DCBs were retrospectively collected at the Shanghai Climate Center and Jinshan Hospital of Fudan University, respectively, in 2016-2020. The distributed lag non-linear and time series model (DLNM) were used to examine the effect of meteorological elements on daily hospital visits due to DCBs.

Results

A total of 26,857 DCBs were collected ranging from 1 to 39 cases per day. The relationship between ambient temperature and DCBs was J-shaped. DCBs were positively correlated with daily mean temperature (rs = 0.588, P < 0.01). The relative risk (RR) of DCBs was associated with high temperature (RR = 1.450; 95% CI [1.220-1.722]). Female was more susceptible to high temperature than male. High temperature increased the risk of DCBs.

Conclusions

The extremely high temperature increased the risk of injuries caused by DCBs, particularly for females. These data may help to develop public health strategies for potentially avoiding the occurrence of DCBs.

Knowledge, attitudes and prevention practices related to dog-mediated rabies in Ethiopia: a systematic review and meta-analysis of observational epidemiological studies from inception to 2023

Background

Rabies is a horrific and neglected zoonotic disease that kills thousands of people worldwide each year and continues to pose threats to public health. Prevention and control of dog-transmitted rabies require mapping the level of understanding, perception, and existing practices to minimize its impacts on health. Therefore, we undertook this systematic review and meta-analysis to pool evidence from available data on knowledge, attitudes, and prevention practices regarding the disease from studies conducted in various areas of Ethiopia.

Methods

Articles were searched in electronic bibliographic medical databases such as the Excerpta Medica database, PubMed, Web of Science, African Journals Online, Google Scholar, and Scopus. We used Microsoft Excel spreadsheets and STATA software version 16 for the data excerption and analysis, respectively. The variability among studies was evaluated via Higgins and Thompson's I2 statistics and the x2 test (significant at p ≤ 0.1). The Dersimonian and Laird random-effect meta-analysis model was used to estimate the pooled effect at a 95% uncertainty interval (UI). Visual inspection and Egger's test (significant at p ≤ 0.05) were used to identify the presence of small-study effects.

Results

The search identified 1,249 electronic records. Of them, 27 studies involving 11,150 participants met the inclusion criteria. The pooled prevalence of a good level of knowledge was 62.24% (95% UI: 48.56, 75.92). Furthermore, the pooled prevalence of a favorable level of attitudes towards rabies and a good level of rabies prevention practices was only 56.73% (95% UI: 47.16, 66.29) and 52.73% (95% UI: 43.32, 62.15), respectively.

Conclusion

The study revealed credible gaps in attitudes and prevention practices, though some level of knowledge about dog-mediated rabies was demonstrated. Therefore, we call for country-wide cross-sectoral collaboration to allow for the realization of a global elimination strategy for dog-mediated human rabies.