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Lima, Peru, has not had a case of canine rabies since 1999. However, Lima remains at risk of rabies reintroduction due to the free movement of dogs from nearby rabies-endemic areas. In Latin America, rabies vaccination campaigns must reach 80% of dogs to halt transmission, but estimates of vaccine coverage are often unavailable, unreliable, or inaccurate. Quantifying virus neutralizing antibodies (VNA) allows monitoring of the immunological status of the canine population, evaluation of the degree of humoral protection to the virus, and assessing, partially, the population response to vaccination. We evaluated the dog population's immunity level against the rabies virus before a mass vaccination campaign in Lima. We collected 141 canine blood samples in the district of Surquillo and quantified rabies virus neutralizing antibody titers using the fluorescent antibody virus neutralization test). We surveyed dogs owners to reconstruct canine vaccination histories. Among dogs previously vaccinated, 73.9% exceeded the seroconversion threshold of > 0.5 IU/mL. Among all dogs, only 58.2% reached the titer limit for seroconversion. Dogs ≤ 1 year old constituted 26.2% of the total canine population and had lower levels of VNA than dogs > 1 year old (χ2 = 9.071; P = 0.028). Importantly, dogs vaccinated with single-pathogen vaccines had higher levels of VNA than those who received combined-pathogen vaccines (χ2 = 7.721; P = 0.005). We provide an important and timely glimpse to the immunity status of the dog population in urban areas of Lima, a metropolis near a dog rabies-endemic region.

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Pneumonia caused by Mycoplasma (M.) hyopneumoniae is one of the major respiratory diseases in swine production. Commercial vaccines for M. hyopneumoniae are widely used in weaned piglets to reduce lung lesions and clinical signs in the downstream flow; however, no information regarding the effect of mass immunization of the breeding herd is available. The aim of this work was to evaluate a mass vaccination protocol for M. hyopneumoniae on the humoral response of sows and their offspring 24 h post-partum (trial registration number 40156). A total of 52 sows from two different farms (13 primiparous and 13 multiparous sows on each farm), one with mass vaccination (MVF) and one without mass vaccination against M. hyopneumoniae (control farm (CF)) were enrolled in this study. Five piglets from each litter were selected, resulting in 260 piglets. Blood was collected from sows and piglets 24 h post-partum for M. hyopneumoniae antibody detection by ELISA. The results showed that primiparous sows from MVF had higher antibody titers compared to multiparous sows of the same farm, and multiparous and primiparous sows from the CF. Similar results were evidenced in their offspring. The findings of this study suggest that mass vaccination results in a more robust serologic response on primiparous sows, which could be the main target of vaccination strategies for the breeding herd.

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In Latin America, there has been tremendous progress towards eliminating canine rabies. Major components of rabies elimination programs leading to these successes have been constant and regular surveillance for rabid dogs and uninterrupted yearly mass dog vaccination campaigns. Unfortunately, vital measures to control COVID-19 have had the negative trade-off of jeopardizing these rabies elimination and prevention activities. We aimed to assess the effect of interrupting canine rabies surveillance and mass dog vaccination campaigns on rabies trends. We built a deterministic compartment model of dog rabies dynamics to create a conceptual framework for how different disruptions may affect rabies virus transmission. We parameterized the model for conditions found in Arequipa, Peru, a city with active rabies virus transmission. We examined our results over a range of plausible values for R0 (1.36-2.0). Also, we prospectively evaluated surveillance data during the pandemic to detect temporal changes. Our model suggests that a decrease in canine vaccination coverage as well as decreased surveillance could lead to a sharp rise in canine rabies within months. These results were consistent over all plausible values of R0. Surveillance data from late 2020 and early 2021 confirms that in Arequipa, Peru, rabies cases are on an increasing trajectory. The rising rabies trends in Arequipa, if indicative to the region as whole, suggest that the achievements made in Latin America towards the elimination of dog-mediated human rabies may be in jeopardy.

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BACKGROUND: Rabies is a viral zoonosis that imposes a substantial disease and economic burden in many developing countries. Dogs are the primary source of rabies transmission; eliminating dog rabies reduces the risk of exposure in humans significantly. Through mass annual dog rabies vaccination campaigns, the national program of rabies control in Mexico progressively reduced rabies cases in dogs and humans since 1990. In 2019, the World Health Organization validated Mexico for eliminating rabies as a public health problem. Using a governmental perspective, we retrospectively assessed the economic costs, effectiveness, and cost-effectiveness of the national program of rabies control in Mexico, 1990-2015. METHODOLOGY: Combining various data sources, including administrative records, national statistics, and scientific literature, we retrospectively compared the current scenario of annual dog vaccination campaigns and post-exposure prophylaxis (PEP) with a counterfactual scenario without an annual dog vaccination campaign but including PEP. The counterfactual scenario was estimated using a mathematical model of dog rabies transmission (RabiesEcon). We performed a thorough sensitivity analysis of the main results. PRINCIPAL FINDINGS: Results suggest that in 1990 through 2015, the national dog rabies vaccination program in Mexico prevented about 13,000 human rabies deaths, at an incremental cost (MXN 2015) of $4,700 million (USD 300 million). We estimated an average cost of $360,000 (USD 23,000) per human rabies death averted, $6,500 (USD 410) per additional year-of-life, and $3,000 (USD 190) per dog rabies death averted. Results were robust to several counterfactual scenarios, including high and low rabies transmission scenarios and various assumptions about potential costs without mass dog rabies vaccination campaigns. CONCLUSIONS: Annual dog rabies vaccination campaigns have eliminated the transmission of dog-to-dog rabies and dog-mediated human rabies deaths in Mexico. According to World Health Organization standards, our results show that the national program of rabies control in Mexico has been highly cost-effective.

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We conducted a cross-sectional survey to better understand the barriers to attendance at canine rabies vaccination campaigns in Haiti. A structured community-based questionnaire was conducted over a 15-day period during May-June 2017, focused on socio-economic status correlated with participation at canine rabies vaccination campaigns. Questions phrased as a bidding game were asked to determine individuals' willingness to pay (WTP) for dog rabies vaccination and willingness to walk (WTW) to fixed-point vaccination campaigns. The Kaplan-Meier estimator was applied to determine relationships between survey variables. Logistic regression was used to examine factors associated with participants' WTP and WTW. A total of 748 households from eight communities were surveyed. Respondents were predominantly female (54.4%) and had a median age of 45 years. The total number of owned dogs reported from households was 926, yielding a human-to-dog ratio in dog-owning households of 5.2:1. The majority of dogs (87.2%) were acquired for security, and 49% were allowed to roam freely; 42.0% of dog owners reported that they were unable to manage (or restrain) their dogs using a leash. Seventy per cent of dog owners were willing to pay up to 15.9 gourdes (0.25 USD) and/or walk up to 75 m to vaccinate their dogs. Households that owned free-roaming dogs, owned dogs for the purpose of companionship and owned dogs that they were unable to walk on a leash were associated with a higher WTP for vaccination. Living in Artibonite Department, having a middle or higher household income, and owning a dog for security purpose were associated with a higher WTW for vaccination. Low leash use and propensity for dogs to roam freely are barriers to successful fixed-point vaccination methods in Haiti, and alternative methods such as door to door (DD), capture-vaccinate-release (CVR) or oral vaccination should be explored. There may be some prospect for fee-for-service vaccination in Haiti; however, this programme should be introduced as a supplement, rather than a replacement for free rabies vaccination programmes so that mass dog vaccination is not discouraged.

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To control and prevent rabies in Latin America, mass dog vaccination campaigns (MDVC) are implemented mainly through fixed-location vaccination points: owners have to bring their dogs to the vaccination points where they receive the vaccination free of charge. Dog rabies is still endemic in some Latin-American countries and high overall dog vaccination coverage and even distribution of vaccinated dogs are desired attributes of MDVC to halt rabies virus transmission. In Arequipa, Peru, we conducted a door-to-door post-campaign survey on >6,000 houses to assess the placement of vaccination points on these two attributes. We found that the odds of participating in the campaign decreased by 16% for every 100 m from the owner's house to the nearest vaccination point (p = 0.041) after controlling for potential covariates. We found social determinants associated with participating in the MDVC: for each child under 5 in the household, the odds of participating in the MDVC decreased by 13% (p = 0.032), and for each decade less lived in the area, the odds of participating in the MDVC decreased by 8% (p<0.001), after controlling for distance and other covariates. We also found significant spatial clustering of unvaccinated dogs over 500 m from the vaccination points, which created pockets of unvaccinated dogs that may sustain rabies virus transmission. Understanding the barriers to dog owners' participation in community-based dog-vaccination programs will be crucial to implementing effective zoonotic disease preventive activities. Spatial and social elements of urbanization play an important role in coverage of MDVC and should be considered during their planning and evaluation.

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Dogs harbor numerous zoonotic pathogens, many of which are controlled through vaccination programs. The delivery of these programs can be difficult where resources are limited. We developed a dynamic model to estimate vaccination coverage and cost-per-dog vaccinated. The model considers the main factors that affect vaccination programs: dog demographics, effectiveness of strategies, efficacy of interventions and cost. The model was evaluated on data from 18 vaccination programs representing eight countries. Sensitivity analysis was performed for dog confinement and vaccination strategies. The average difference between modelled vaccination coverage and field data was 3.8% (2.3%-5.3%). Central point vaccination was the most cost-effective vaccination strategy when >88% of the dog population was confined. More active methods of vaccination, such as door-to-door or capture-vaccinate-release, achieved higher vaccination coverage in free-roaming dog populations but were more costly. This open-access tool can aid in planning more efficient vaccination campaigns in countries with limited resources.

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Although the use of vaccines has controlled enteric diseases in dogs in many developed countries, vaccine coverage is still under optimal situation in Brazil. There is a large population of nonimmunized dogs and few studies about the identification of the viruses associated with diarrhea. To address this situation, stool samples from 325 dogs were analyzed by polymerase chain reaction for the detection of common enteric viruses such as Canine adenovirus (CAdV), Canine coronavirus (CCoV), Canine distemper virus (CDV), Canine rotavirus (CRV) and Carnivorous protoparvovirus 1 (canine parvovirus 2; CPV-2). At least one of these species was detected in 56.6% (184/325) of the samples. The viruses detected most frequently in either diarrheic or nondiarrheic dog feces were CPV-2 (54.3% of the positive samples), CDV (45.1%) and CCoV (30.4%), followed by CRV (8.2%) and CAdV (4.9%). Only one agent was detected in the majority of the positive samples (63%), but co-infections were present in 37% of the positive samples and mainly included CDV and CPV-2. The data presented herein can improve the clinical knowledge in regions with low vaccine coverage and highlight the need to improve the methods used to control these infectious diseases in domestic dogs.(AU)

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Through national efforts and regional cooperation under the umbrella of the Regional Program for the Elimination of Rabies, dog and human rabies have decreased significantly in Latin America and Caribbean (LAC) countries over the last three decades. To achieve this decline, LAC countries had to develop national plans, and consolidate capabilities such as regular mass dog vaccination, opportune post-exposure prophylaxis and sensitive surveillance. This paper presents longitudinal data for 21 LAC countries on dog vaccination, PEP and rabies surveillance collected from the biannual regional meeting for rabies directors from 1998-2014 and from the Regional Epidemiologic Surveillance System for Rabies (SIRVERA). Differences in human and dog rabies incidence rates and dog vaccination rates were shown between low, middle and high-income countries. At the peak, over 50 million dogs were vaccinated annually in national campaigns in the countries represented. The reported number of animal exposures remained fairly stable during the study period with an incidence rate ranging from 123 to 191 reported exposures per 100,000 people. On average, over 2 million doses of human vaccine were applied annually. In the most recent survey, only 37% of countries reported that they had sufficient financial resources to meet the program objectives. The data show a sufficient and sustained effort of the LAC countries in the area of dog vaccination and provide understanding of the baseline effort required to reduce dog-mediated rabies incidence.

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Conocer la estructura, el tamaño y la dinámica de la población canina de un local es importante para planear programas de control de zoonosis. Uno de esos programas es respecto a las campañas de vacunación contra la Rabia en perros, que en la ciudad de Botucatu, São Paulo, Brasil, se realizan desde 1968. En este estúdio, fueron estimados parâmetros relacionados a la dinámica de la población canina en la ciudad para perros vacunados contra la Rabia durante la realización de diez campañas anuales contra la Rabia, en el período de 2005 a 2014. Los datos para las evaluaciones fueron obtenidos de fichas cadastrales de los perros vacunados en las campañas. Para el análisis estadístico se utilizaron test no paramétricos de Mann-Whitney e Kruskal-Wallis. Los estúdios permitieron concluir: 1) a um número mayor de animales entre 1 a 5 años de edad; 2) los dueños llevan sus animales para vacunar en las campañas, por lo tanto tardan en entender la importancia de la primer vacunación, con el tempo tienen conciencia de la necesidad de la vacunación anual; 3) la comparación de la categoria sexo en los perros no tiene diferencia estadística; 4) cuando evaluado el porcentaje de vacunación durante los últimos diez años, el año de 2014 fue el que presentó porcentaje menor, con 64% de perros vacunados. Los parâmetros de la dinâmica de la población canina es este estúdio podran auxiliar para la elaboración de programas de control de zoonosis transmitidas por perros en Botucatu, São Paulo, Brasil.

Knowing the structure, size and dynamics of the canine population of a town is important for planning the zoonoses control programs. One of these programs the vaccination campaigns against rabies in dogs performed in the city of Botucatu, Brazil, since 1968. In this study, we estimated parameters related to the canine population dynamics in the Botucatu for dogs vaccinated against rabies during the performance of 10 anti-rabies campaign in the period from 2005 to 2014. The data for the evaluations were obtained from the records of entries of dogs vaccinated in the campaign. Mann-Whitney and Kruskal-Wallis non-parametric tests were used for the statistical analysis. The used tests allowed the following conclusions: 1) the majority of the animals are in between 1 and 5 year-old; 2) the owners have taken their animals to be vaccinated on the campaigns but the population usually delays to be aware of the primary vaccination; with the past of time, dog owners become aware of the importance of the annual vaccinations; 3) the comparison among the dog gender is not statistically significant; 4) 2014 was the year with the smallest vaccination coverage (64%) in the past ten years. The parameters of the canine population dynamics in this study provide the aid for the development of programs for the control of zoonoses transmited from dogs in Botucatu.

Conhecer a estrutura, o tamanho e a dinâmica da população canina de uma localidade é importante para o planejamento de programas de controle de zoonoses. Um desses programas diz respeito às campanhas de vacinação contra a Raiva de cães que, no município de Botucatu, SP, são realizadas desde 1968. No presente estudo, foram estimados parâmetros relacionados à dinâmica populacional canina no Município para cães vacinados contra a Raiva durante a realização de dez campanhas anuais contra a Raiva, no período de 2005 a 2014. Os dados para as avaliações foram obtidos a partir das fichas de cadastro dos cães vacinados nas campanhas. Para análise estatística foram utilizados testes não paramétricos de Mann-Whitney e Kruskal-Wallis. Os estudos realizados permitiram as seguintes conclusões: 1) há um maior número de animais entre 1 a 5 anos de idade; 2) os proprietário tem levado seus animais para serem vacinados nas campanhas porém a população normalmente demora a se conscientizar da importância da primovacinação; com o passar do tempo, os donos dos cães vão tomando consciência da necessidade das vacinações anuais; 3) a comparação entre a categoria sexo dos cães não é estatisticamente significativa; 4) quando avaliada a cobertura vacinal durante os últimos dez anos, o ano de 2014 foi que o que apresentou uma menor cobertura vacinal, 64% dos cães vacinados. Os parâmetros da dinâmica populacional canina neste estudo servirão de auxílio para a elaboração de programas de controle de zoonoses transmitidas pelos cães em Botucatu.

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