A comparison of population estimation techniques for individually unidentifiable free-roaming dogs

Evaluation of Dynamics, Demography and Estimation of Free-Roaming Dog Population in Herat City, Afghanistan

FRDs pose a serious challenge in countries where dog-bite-related rabies is endemic. Understanding the size and core demographic characteristics of FRD populations is essential for the planning and implementation of effective dog-population and canine-rabies-control programmes. The photographic sight-resight method was used to estimate the FRD population and evaluate its demographic characteristics in Herat city. A total of 928 free-roaming dogs (FRD) were identified through 3172 sightings, and the total free-roaming population was estimated to amount to 1821 (95% CI: 1565-2077), which led to the estimation of 10 dogs/km² and the human-to-FRD ratio of 315:1. The male-to-female ratio was 2.85:1. The majority of them were healthy, with an ideal body score. Although the FRD density is considered low, it is still a concern and significant, since the majority of the people are unaware of the importance of canine populations in the transmission of zoonotic diseases such as rabies, and there were no specific measures for managing and controlling FRD populations. The information gained can be useful in animal health planning to design effective dog-population-control programmes, and for the planning of national rabies-prevention programmes.

A Review and Analysis of the National Dog Population Management Program in Chile

Free-roaming dogs are a worldwide problem, with Chile having some of the highest human-to-dog ratios in the world. In 2017, Law 21.020 was promulgated and the federal government developed a national responsible pet ownership program. The objectives of this article are to describe and discuss the dog-related components of the program, to design a tool for determining human-to-dog ratios in Chile, and to make recommendations to managers to improve the program outcomes. The overarching goal of the program was to mitigate the conflict between humans and dogs, but many of the interventions were animal-focused and the indicators did not consider the perception of the Chilean public. Using human density data and known dog populations, we found that as the human density increased, there were fewer dogs per person. Veterinary services and sterilizations were the mainstay of the program and were offered for free to citizens. Education was offered to all ages through public events, as well as municipality and organization activities. The identification of dogs was obligatory for dog owners. Enforcement was not included in the program. The recommendations are to conduct preintervention baseline data collections and to tailor interventions and indicators appropriately; to use dog population size estimates determined at the local level rather than a country-wide estimate; to replace free veterinary services with low-cost sterilization campaigns; to create sustainable plans for education; and to create enforcement teams in communities.

Spatial Distribution and Population Estimation of Dogs in Thailand: Implications for Rabies Prevention and Control

Poor management of dog populations causes many problems in different countries, including rabies. To strategically design a dog population management, certain sets of data are required, such as the population size and spatial distribution of dogs. However, these data are rarely available or incomplete. Hence, this study aimed to describe the characteristics of dog populations in Thailand, explore their spatial distribution and relevant factors, and estimate the number of dogs in the whole country. First, four districts were selected as representatives of each region. Each district was partitioned into grids with a 300-m resolution. The selected grids were then surveyed, and the number of dogs and related data were collected. Random forest models with a two-part approach were used to quantify the association between the surveyed dog population and predictor variables. The spatial distribution of dog populations was then predicted. A total of 1,750 grids were surveyed (945 grids with dog presence and 805 grids with dog absence). Among the surveyed dogs, 86.6% (12,027/13,895) were owned. Of these, 51% were classified as independent, followed by confined (25%), semi-independent (21%), and unidentified dogs (3%). Seventy-two percent (1,348/1,868) of the ownerless dogs were feral, and the rest were community dogs. The spatial pattern of the dog populations was highly distributed in big cities such as Bangkok and its suburbs. In owned dogs, it was linked to household demographics, whereas it was related to community factors in ownerless dogs. The number of estimated dogs in the entire country was 12.8 million heads including 11.2 million owned dogs (21.7 heads/km²) and 1.6 million ownerless dogs (3.2 heads/km²). The methods developed here are extrapolatable to a larger area and use much less budget and manpower compared to the present practices. Our results are helpful for canine rabies prevention and control programs, such as dog population management and control and rabies vaccine allocation.

Free-roaming dog population dynamics in Ranchi, India

Rabies causes approximately 20,000 human deaths in India each year. Nearly all of these occur following dog bites. Large-scale, high-coverage dog rabies vaccination campaigns are the cornerstone of rabies elimination strategies in both human and dog populations, although this is particularly challenging to achieve in India as a large proportion of the dog population are free-roaming and unowned. Further, little is known about free-roaming dog ecology in India which makes defining optimum vaccination strategies difficult. In this study, data collected using a mobile phone application during three annual mass vaccination and neutering (surgical sterilisation of both males and females) campaigns of free-roaming dogs in Ranchi, India (during which a total of 43,847 vaccinations, 26,213 neuter surgeries and 28,172 re-sight observations were made) were interrogated, using two novel approaches to estimate the proportion of neutered dogs that were lost from the city (assumed due to mortality or migration) between campaign years. Analysis revealed high losses of neutered dogs each year, ranging from 25.3% (28.2-22.8) to 55.8% (57.0-54.6). We also estimated that the total population declined by 12.58% (9.89-15.03) over the three-year period. This demonstrates that there is a high turnover of free-roaming dogs and that despite neutering a large number of dogs in an annual sterilisation campaign, the decline in population size was modest over a three-year time period. These findings have significant implications for the planning of rabies vaccination campaigns and population management programmes as well as highlighting the need for further research into the demographics of free-roaming, unowned dogs in India.

Owned and free-roaming dogs in the North West of Tunisia: estimation, characteristics and application for the control of dog rabies

Understanding the structure of dog population and the evaluation of the accessibility of dogs to vaccination is essential to succeed in the fight against dog rabies and to adapt the strategy of its control. We studied the characteristics of the unowned and owned dogs using the beck method during a rabies vaccination campaign in randomly selected sectors (urban and rural sites) in the North West of Tunisia. During a door-to-door investigation of households, data on owned dogs were collected to describe the owned population dog. A photographic-recapture method was used to characterize and estimate the size of the unowned dogs. A total of 1432 households accounting for 5403 inhabitants were interviewed during the survey (1298 (90.6%) in the urban site and 134 (9.3%) in the rural site). The dog-owning households were significantly higher in the rural site (76.1% (102/134)) compared to the urban site (17.8% (231/1298)) (P < 0.000000). Of the 17.8% dog-owning households in urban site, 58.4% owned one dog and 9% between 4 and 8 dogs. While, of the 76.1% dog-owning households in rural site, 24.5% owned one dog and 32.3% owned between 4 and 10 dogs. The dog: human ratio was 1:11 in the urban site and 1:1.6 in the rural site. The dog population density was estimated at 16 dogs/km2 and 4 dogs/km2 in the urban and rural sites, respectively. The confinement practices varied significantly among the urban and rural sites (P < 0.000000). The percentage of free-roaming owned dogs was 51.1% in the rural site and 31.4% in the urban site. More than 60.0% of the owned dogs in the urban site were confined. The majority of dogs in the rural site were born in the house, although, a high percentage (56.7%) of owned dogs in the urban site was adopted from neighbours, others sectors, or countries. The vaccination coverage findings indicated that 77.8% and 84.2% of the owned dog were vaccinated in the urban and rural sites, respectively. The estimated size of the free-roaming dogs was 72 dogs in the urban site (Kalaat Senan) and 16 dogs in the rural site (Sod el Khir).

Towards rabies elimination in the Asia-Pacific region: From theory to practice

Rabies is a major neglected zoonotic disease and causes a substantial burden in the Asian region. Currently, Pacific Oceania is free of rabies but enzootic areas throughout southeast Asia represent a major risk of disease introduction to this region. On September 25-26, 2019, researchers, government officials and related stakeholders met at an IABS conference in Bangkok, Thailand to engage on the topic of human rabies mediated by dogs. The objective of the meeting was focused upon snowballing efforts towards achieving substantial progress in rabies prevention, control and elimination within Asia by 2030, and thereby to safeguard the Pacific region. Individual sessions focused upon domestic animal, wildlife and human vaccination; the production and evaluation of quality, safety and efficacy of existing rabies biologics; and the future development of new products. Participants reviewed the progress to date in eliminating canine rabies by mass vaccination, described supportive methods to parenteral administration by oral vaccine application, considered updated global and local approaches at human prophylaxis and discussed the considerable challenges ahead. Such opportunities provide continuous engagement on disease management among professionals at a trans-disciplinary level and promote new applied research collaborations in a modern One Health context.