Last-mile delivery increases vaccine uptake in Sierra Leone.

Less than 30% of people in Africa received a dose of the COVID-19 vaccine even 18 months after vaccine development1. Here, motivated by the observation that residents of remote, rural areas of Sierra Leone faced severe access difficulties2, we conducted an intervention with last-mile delivery of doses and health professionals to the most inaccessible areas, along with community mobilization. A cluster randomized controlled trial in 150 communities showed that this intervention with mobile vaccination teams increased the immunization rate by about 26 percentage points within 48-72 h. Moreover, auxiliary populations visited our community vaccination points, which more than doubled the number of inoculations administered. The additional people vaccinated per intervention site translated to an implementation cost of US $33 per person vaccinated. Transportation to reach remote villages accounted for a large share of total intervention costs. Therefore, bundling multiple maternal and child health interventions in the same visit would further reduce costs per person treated. Current research on vaccine delivery maintains a large focus on individual behavioural issues such as hesitancy. Our study demonstrates that prioritizing mobile services to overcome access difficulties faced by remote populations in developing countries can generate increased returns in terms of uptake of health services3.

Coverage for pertussis vaccination during pregnancy with 4 models of vaccine delivery: a quasiexperimental, multicentre observational study.

BACKGROUND: Vaccination of pregnant people with a vaccine containing acellular pertussis (tetanus-diphtheria-acellular pertussis [Tdap]) has been recommended in Canada since 2018, and the evaluation of delivery models for efficient maternal Tdap administration is a priority for the Quebec Ministry of Health. We implemented 3 vaccine delivery models, in addition to the existing standard of practice model, and compared the vaccine coverage achieved by the 4 models in Quebec. METHODS: In this quasiexperimental, multicentre observational study, we recruited pregnant people at less than 21 weeks' gestation in 4 Quebec regions from April to October 2019. We compared 4 vaccine delivery models: local community service centres (centre local de services communautaires [CLSCs], baseline), family medicine groups (FMGs), obstetrics clinic and the oral glucose challenge test (OGCT). In addition to the CLSCs, 3 FMGs, 1 obstetric clinic and a hospital-based OGCT screening program participated. We determined vaccination status from a self-reported questionnaire, the Quebec Immunization Registry or medical charts. We compared model-specific (for participants recruited to a model and subsequently vaccinated within that model) and overall vaccine coverage (considering all vaccine delivery pathways) and used logistic regression to adjust for sociodemographic variables. RESULTS: Overall, 946 of 1000 recruited pregnant people were eligible for analyses. Vaccination via the FMGs achieved the highest model-specific vaccine coverage (67.8%, 95% confidence interval [CI] 60.5%-74.4%), but coverage was not significantly different from the CLSCs (63.8%, 95% CI 57.6%-69.6%). For overall vaccine coverage, the FMG (86.5%, 95% CI 80.6%-90.9%) and obstetrics models (85.9%, 95% CI 80.9%-89.7%) achieved significantly higher vaccine coverage than the CLSCs (66.3%, 95% CI 60.1%-71.9%). The OGCT model did not improve overall vaccine coverage (61.8%, 95% CI 56.1%-67.2%). INTERPRETATION: Compared with CLSCs, overall vaccine coverage was higher when Tdap was offered in FMGs or an obstetrics clinic providing prenatal care. Health professionals involved in pregnancy follow-up recommending and offering the vaccine may be a key factor in optimizing vaccine coverage.

Effect of the mandatory vaccination law on measles and rubella incidence and vaccination coverage in Italy (2013-2019).

Despite the introduction of the trivalent vaccine (measles, mumps, rubella) more than 20 years ago, measles outbreaks have occurred in Europe, including Italy, due to its underutilization. In Italy mandatory vaccination was established in 2017 (Decree Law 119/2017). This study aimed at evaluating the impact of mandatory vaccination and determining the trend in vaccination coverage for measles and rubella in Italy. We retrieved data from the Annual Status Update, a form sent annually by the Italian National Verification Committee to the Regional Verification Committee for Europe, from 1st January 2013 to 31st December 2019. Since the beginning of 2013, 14,788 cases of measles have been reported, ranging from 256 (3.9 x 1,000,000) to 5,397 (88.4 x 1,000,000) compared to 259 rubella cases for the same period. From 2013 to 2015, vaccination coverage decreased for the first dose of measles (90.4% to 85.3%) and rubella vaccine (90.3% to 85.2%), but then it increased significantly, reinforced by the Italian Decree Law, reaching 94.4% in 2019. The trend for the second dose showed a decrease from 2013 to 2016 (84.1% to 82.2% for measles and 83.7% to 82.0% for rubella), but then increased significantly and reached 90.2% in 2019 for measles and 90.0% for rubella. The mandatory vaccination law has resulted in a significant increase in vaccination coverage for measles and rubella in Italy, and demonstrates encouraging progress toward the 95% target and the restriction of measles transmission. Special attention should be paid to maintaining and further improving vaccination coverage.

Tetanus Toxoid Vaccination Coverage and Associated Factors among Childbearing Women in Ethiopia: A Systematic Review and Meta-Analysis.

BACKGROUND: Tetanus is a bacterial disease caused by the Clostridium tetani, which is a highly fatal, noncommunicable, and toxin-mediated disease. Globally, maternal and neonatal tetanus is a public health problem due to low maternal tetanus toxoid immunization. Ethiopia has the highest neonatal mortality and morbidity related to tetanus due to low tetanus toxoid immunization and the high number of home deliveries. The main objective of this systematic review and meta-analysis was to estimate the pooled coverage of at least two doses of tetanus toxoid immunization, and the pooled effect sizes of associated factors in Ethiopia. METHODS: Primary studies for this review were searched from the PubMed/MEDLINE online, ScienceDirect, Hinari, Google, and Google Scholar databases. Primary articles published from 2010 up to August 30, 2020, were included in this meta-analysis. Data were extracted in Microsoft Excel format and exported to STATA Version 14.0. A random-effects meta-analysis model was used to estimate the pooled coverage of two or more tetanus toxoid immunizations and its associated factors. Heterogeneity was evaluated by the I 2 test. Egger's weighted regression test was used to assess publication bias. RESULTS: We retrieved 212 records; of these, 199 articles were excluded for reasons. Finally, 14 studies were included in this meta-analysis. The pooled estimate of receiving at least two doses of tetanus toxoid immunization coverage in Ethiopia was 52.2% (95% CI: 42.47-61.93, I 2 = 98.4%). Antenatal care (OR = 7.8 (95% CI: 3.2, 19.2), I 2 = 96.3%), media exposure (OR = 8.3 (95% CI: 2.1, 33.3), I 2 = 98.1%), distance from the health facility (OR = 2.64 (95% CI: 1.1, 6.6), I 2 = 94.1%), educational status of women (OR = 4.7 (95% CI: 2.07, 9.56), I 2 = 94.2%), and educational status of husbands (OR = 2.995 (95% CI: 1.194, 7.512), I 2 = 92.5%) were factors significantly associated with receiving at least two doses of tetanus toxoid immunization coverage in Ethiopia. CONCLUSIONS: The coverage of tetanus toxoid immunization among childbearing women was low in Ethiopia. Strengthening maternal health service utilization (antinatal care and institutional delivery) to the nearest health facility even in health posts and empowering education for both women and their husbands is recommended to increase tetanus toxoid immunization coverage in Ethiopia.

An evaluation of strategies to achieve greater than 90% coverage of maternal influenza and pertussis vaccines including an economic evaluation.

BACKGROUND: Maternal immunisation is an essential public health intervention aimed at improving the health outcomes for pregnant women and providing protection to the newborn. Despite international recommendations, safety and efficacy data for the intervention, and often a fully funded program, uptake of vaccines in pregnancy remain suboptimal. One possible explanation for this includes limited access to vaccination services at the point of antenatal care. The aim of this study is to evaluate the change in vaccine coverage among pregnant women following implementation of a modified model of delivery aimed at improving access at the point of antenatal care, including an economic evaluation. METHODS: This prospective multi-centre study, using action research design, across six maternity services in Victoria, Australia, evaluated the implementation of a co-designed vaccine delivery model (either a pharmacy led model, midwife led model or primary care led model) supported by provider education. The main outcome measure was influenza and pertussis vaccine uptake during pregnancy and the incremental cost of the new model (compared to existing models) and the cost-effectiveness of the new model at each participating health service. RESULTS: Influenza vaccine coverage in 2019 increased between 50 and 196% from baseline. All services reduced their average cost per immunisation under the new platforms due to efficiencies achieved in the delivery of maternal immunisations. This cost saving ranged from $9 to $71. CONCLUSION: Our study demonstrated that there is no 'one size fits all' model of vaccine delivery. Future successful strategies to improve maternal vaccine coverage at other maternity services should be site specific, multifaceted, targeted at the existing barriers to maternal vaccine uptake, and heavily involve local stakeholders in the design and implementation of these strategies. The cost-effectiveness analysis indicates that an increase in maternal influenza immunisation uptake can be achieved at a relatively modest cost through amendment of maternal immunisation platforms.

Real-time geospatial analysis identifies gaps in COVID-19 vaccination in a minority population.

COVID-19 vaccination is being rapidly rolled out in the US and many other countries, and it is crucial to provide fast and accurate assessment of vaccination coverage and vaccination gaps to make strategic adjustments promoting vaccine coverage. We reported the effective use of real-time geospatial analysis to identify barriers and gaps in COVID-19 vaccination in a minority population living in South Texas on the US-Mexico Border, to inform vaccination campaign strategies. We developed 4 rank-based approaches to evaluate the vaccination gap at the census tract level, which considered both population vulnerability and vaccination priority and eligibility. We identified areas with the highest vaccination gaps using different assessment approaches. Real-time geospatial analysis to identify vaccination gaps is critical to rapidly increase vaccination uptake, and to reach herd immunity in the vulnerable and the vaccine hesitant groups. Our results assisted the City of Brownsville Public Health Department in adjusting real-time targeting of vaccination, gathering coverage assessment, and deploying services to areas identified as high vaccination gap. The analyses and responses can be adopted in other locations.

Impact of Vax-a-Million Lottery on COVID-19 Vaccination Rates in Ohio.

BACKGROUND: A decrease in coronavirus disease 2019 (COVID-19) vaccination rates has led some states to consider various incentives to boost demand for vaccines. On May 13, 2021, Ohio announced a free weekly lottery for individuals who received at least 1 COVID-19 vaccination. This study seeks to rigorously quantify the impact of Ohio's vaccination lottery. METHODS: A synthetic control consisting of a weighted combination of other states was used to approximate the demographic characteristics, new cases, and vaccination rates in Ohio prior to the lottery announcement. The difference in vaccination rates in Ohio and the synthetic control following the lottery announcement was then used to estimate the lottery's impact. RESULTS: Prior to the lottery announcement, Ohio and synthetic Ohio had similar demographic characteristics and new case rates. Ohio and synthetic Ohio also had identical first vaccination rates. By the final lottery enrollment date of June 20, the percentage of the population with first vaccinations increased to 47.41% in Ohio and 46.43% in synthetic Ohio for a difference of 0.98% (95% confidence interval [CI] 0.42-1.54). CONCLUSION: An additional 114,553 Ohioans received vaccinations as a result of the Vax-a-Million program (95% CI 49,094-180,012) at a cost of approximately $49 per Ohioan vaccinated (95% CI $31-$114). However, a majority of Ohioans remained unvaccinated by the end of the lottery, indicating that additional efforts are needed to address barriers to vaccination. This synthetic control approach may also be useful to evaluate other COVID-19 incentive programs.

Measles, mumps, rubella prevention: how can we do better?

INTRODUCTION: Measles, mumps, and rubella incidence decreased drastically following vaccination programs' implementation. However, measles and mumps' resurgence was recently reported, outbreaks still occur, and challenges remain to control these diseases. AREAS COVERED: This qualitative narrative review provides an objective appraisal of the literature regarding current challenges in controlling measles, mumps, rubella infections, and interventions to address them. EXPERT OPINION: While vaccines against measles, mumps, and rubella (including trivalent vaccines) are widely used and effective, challenges to control these diseases are mainly related to insufficient immunization coverage and changing vaccination needs owing to new global environment (e.g. traveling, migration, population density). By understanding disease transmission peculiarities by setting, initiatives are needed to optimize vaccination policies and increase vaccination coverage, which was further negatively impacted by COVID-19 pandemic. Also, awareness of the potential severity of infections and the role of vaccines should increase. Reminder systems, vaccination of disadvantaged, high-risk and difficult-to-reach populations, accessibility of vaccination, healthcare infrastructure, and vaccination services management should improve. Outbreak preparedness should be strengthened, including implementation of high-quality surveillance systems to monitor epidemiology. While the main focus should be on these public health initiatives to increase vaccination coverage, slightly more benefits could come from evolution of current vaccines.

PLAIN LANGUAGE SUMMARYWhat is the context?Measles, mumps, and rubella are highly contagious diseases associated with significant medical and societal burden. Effective vaccines against these diseases are available, and the implementation of vaccination programs drastically reduced disease incidence globally. However, reports of measles and mumps outbreaks in the last few years highlight remaining challenges to eliminate these diseases.What does the review highlight?We conducted a literature review to identify challenges associated with controlling measles, mumps, and rubella infections, and interventions needed to address them. We identified 11 challenges mainly related to low immunization coverage and vaccine characteristics. Societal challenges could be addressed by increasing awareness of disease severity and vaccines impact, targeting high-risk, unvaccinated, and under-vaccinated populations, improving vaccination access, setting up clear outbreak preparedness plans, and implementing country-specific vaccination policies. System weaknesses could be addressed through improving vaccination services and health infrastructure, implementing high-quality surveillance, patient invite, and reminder systems, ensuring vaccine implementation and long-term supply. Interventions related to vaccine characteristic challenges could include adaptation of vaccination schedules (shorter interval between doses, administration of a third dose) and development of vaccines against emerging strains.What is the take-home message?Policymakers should support the following strategies to increase vaccination coverage and reach elimination of measles, mumps, and rubella: strengthening health systems and vaccination access; raising awareness of disease severity and vaccination impact; limiting disease propagation owing to global changing environment and population dynamics (traveling, migration); improving surveillance systems to rapidly address the immunity gaps against disease resurgence.

The Challenge of Achieving Immunity Through Multiple-Dose Vaccines in Madagascar.

Administration of many childhood vaccines requires that multiple doses be delivered within a narrow time window to provide adequate protection and reduce disease transmission. Accurately quantifying vaccination coverage is complicated by limited individual-level data and multiple vaccination mechanisms (routine and supplementary vaccination programs). We analyzed 12,541 vaccination cards from 6 districts across Madagascar for children born in 2015 and 2016. For 3 vaccines-pentavalent diphtheria-tetanus-pertussis-hepatitis B-Haemophilus influenzae type b vaccine (DTP-HB-Hib; 3 doses), 10-valent pneumococcal conjugate vaccine (PCV10; 3 doses), and rotavirus vaccine (2 doses)-we used dates of vaccination and birth to estimate coverage at 1 year of age and timeliness of delivery. Vaccination coverage at age 1 year for the first dose was consistently high, with decreases for subsequent doses (DTP-HB-Hib: 91%, 81%, and 72%; PCV10: 82%, 74%, and 64%; rotavirus: 73% and 63%). Coverage levels between urban districts and their rural counterparts did not differ consistently. For each dose of DTP-HB-Hib, the overall percentage of individuals receiving late doses was 29%, 7%, and 6%, respectively; estimates were similar for other vaccines. Supplementary vaccination weeks, held to help children who had missed routine care to catch up, did not appear to increase the likelihood of being vaccinated. Maintaining population-level immunity with multiple-dose vaccines requires a robust stand-alone routine immunization program.

Ensuring High and Equitable COVID-19 Vaccine Uptake Among Patients With IBD.

The recent emergency use authorization of a third COVID-19 vaccine means that most patients with inflammatory bowel disease (IBD) will soon be eligible to be vaccinated. Gastroenterology clinicians should be prepared to address patients' concerns regarding safety and efficacy of vaccines. They should also strongly recommend that all their patients be vaccinated with a COVID-19 vaccine. Additionally, they should be prepared to educate patients about logistics that will result in successful vaccination completion. All these measures will be crucial to ensure high uptake among their patients with IBD.

Effects of engaging communities in decision-making and action through traditional and religious leaders on vaccination coverage in Cross River State, Nigeria: A cluster-randomised control trial.

BACKGROUND: Vaccination coverage levels fall short of the Global Vaccine and Action Plan 90% target in low- and middle- income countries (LMICs). Having identified traditional and religious leaders (TRLs) as potential public health change agents, this study aimed at assessing the effect of training them to support routine immunisation for the purpose of improving uptake of childhood vaccines in Cross River State, Nigeria. METHODS: A cluster-randomised controlled study was conducted between 2016 and 2019. Of the 18 Local Government Areas (LGA) in Cross River State, eight (four urban and four rural LGAs) were randomized into the intervention and control study arms. A multi-component intervention involving the training of traditional and religious leaders was implemented in the four intervention LGAs. Baseline, midline and endline surveys collected information on children aged 0-23 months. The effect of the intervention on outcomes including the proportion fully up-to-date with vaccination, timely vaccination for pentavalent and measles vaccines, and pentavalent 1-3 dropout rates were estimated using logistic regression models using random effects to account for the clustered data. RESULTS: A total of 2598 children at baseline, 2570 at midline, and 2550 at endline were included. The intervention was effective in increasing the proportion with at least one vaccine (OR 12.13 95% CI 6.03-24.41p<0.001). However, there was no evidence of an impact on the proportion of children up-to-date with vaccination (p = 0.69). It was effective in improving timeliness of Pentavalent 3 (OR 1.55; 95% CI: 1.14, 2.12; p = 0.005) and Measles (OR 2.81; 96% CI: 1.93-4.1; p<0.001) vaccination. The odds of completing Pentavalent vaccination increased (OR = 1.66 95% CI: 1.08,2.55). CONCLUSION: Informal training to enhance the traditional and religious leaders' knowledge of vaccination and their leadership role can empower them to be good influencers for childhood vaccination. They constitute untapped resources in the community to boost routine immunisation. Pan African Clinical Trial Registry (PACTR) PACTR202008784222254.

COVID-19 vaccines: what happened to evidence-based medicine?

The UK government recently decided to extend the interval between the first dose of the Pfizer BioNTech and AstraZeneca COVID-19 vaccines from 3 weeks to 12 weeks to maximise the number of people receiving the initial dose, despite the trials only providing vaccine efficacy data based on a schedule of 21 days between doses. This editorial discusses whether there is evidence to support this policy change.

Implementing WHO guidance on conducting and analysing vaccination coverage cluster surveys: Two examples from Nigeria.

In 2015, the World Health Organization substantially revised its guidance for vaccination coverage cluster surveys (revisions were finalized in 2018) and has since developed a set of accompanying resources, including definitions for standardized coverage indicators and software (named the Vaccination Coverage Quality Indicators-VCQI) to calculate them.-The current WHO vaccination coverage survey manual was used to design and conduct two nationally representative vaccination coverage surveys in Nigeria-one to assess routine immunization and one to measure post-measles campaign coverage. The primary analysis for both surveys was conducted using VCQI. In this paper, we describe those surveys and highlight some of the analyses that are facilitated by the new resources. In addition to calculating coverage of each vaccine-dose by age group, VCQI analyses provide insight into several indicators of program quality such as crude coverage versus valid doses, vaccination timeliness, missed opportunities for simultaneous vaccination, and, where relevant, vaccination campaign coverage stratified by several parameters, including the number of previous doses received. The VCQI software furnishes several helpful ways to visualize survey results. We show that routine coverage of all vaccines is far below targets in Nigeria and especially low in northeast and northwest zones, which also have highest rates of dropout and missed opportunities for vaccination. Coverage in the 2017 measles campaign was higher and showed less geospatial variation than routine coverage. Nonetheless, substantial improvement in both routine program performance and campaign implementation will be needed to achieve disease control goals.

Vaccines and routine immunization strategies during the COVID-19 pandemic.

Severe acute respiratory syndrome coronavirus 2 related disease (COVID-19) is now responsible for one of the most challenging and concerning pandemics. By August 2020, there were almost 20 million confirmed cases worldwide and well over half-million deaths. Since there is still no effective treatment or vaccine, non-pharmaceutical interventions have been implemented in an attempt to contain the spread of the virus. During times of quarantine, immunization practices in all age groups, especially routine childhood vaccines, have also been interrupted, delayed, re-organized, or completely suspended. Numerous high-income as well as low- and middle-income countries are now experiencing a rapid decline in childhood immunization coverage rates. We will, inevitably, see serious consequences related to suboptimal control of vaccine-preventable diseases (VPDs) in children concurrent with or following the pandemic. Routine pediatric immunizations of individual children at clinics, mass vaccination campaigns, and surveillance for VPDs must continue as much as possible during pandemic.

The vaccination coverage in dispensaries on Mayotte Island is lacking for natives and migrants alike.

OBJECTIVE: Assessing the vaccination coverage rate in Mayotte dispensaries. PATIENTS AND METHODS: Prospective study in three dispensaries from June to July 2019. RESULTS: Of the 162 patients included, 78% (126/162) were natives of the island and 19% (30/162) were from the Comoros Islands. Twenty-three percent (37/162) were up-to-date on their mandatory vaccinations, 45% (73/162) were not and 32% (52/162) had unknown vaccination status. There was no difference in relation to their origin. Some vaccinations were strictly followed (MMR, Hepatitis B…) others were not (HiB, meningitides…). The vaccination coverage rate and its traceability are altogether lacking whatever the age or origin of patients. Efforts must be made in order to increase the vaccination coverage rate among people who, from our experience, do not oppose vaccination in any way.

Influenza vaccination coverage at community pharmacies: Positioning, needs, expectations and involvement of community pharmacists in the Franche-Comté region.

INTRODUCTION: Influenza vaccination coverage currently remains below the 75% recommended threshold by the World Health Organization. To correct this situation, experiments have been successively carried out in France to enable community pharmacists to vaccinate at-risk populations. In this context, a study was conducted with pharmacists from the French Franche-Comté region to evaluate their positioning, needs and expectations regarding influenza vaccination at community pharmacies. MATERIALS AND METHODS: A survey was created and sent to licensed pharmacists in March of 2018. This consisted of 4 parts: characteristics of the community pharmacy; positioning of the pharmacist regarding vaccinations carried out at the pharmacy; training needs and expectations; and willingness to implement vaccinations. RESULTS: The participation rate in this survey was 32% (137/427). More than 90% of the pharmacists agreed that community pharmacies' assets were adequate for the implementation of these vaccinations (accessibility and availability), although 52% considered this complicated. Their main fears were reluctance from patients and conflicts of interest with other health professionals authorized to vaccinate (58%). The needs and expectations regarding pharmacy student training were essential for 94% of them as well as continuous training of practicing pharmacists (96%). The willingness of pharmacists to vaccinate stemmed from the fact that influenza vaccination coverage would increase for at-risk subjects (36%). CONCLUSION: This survey allowed us to assess the favorable positioning and the real interest of pharmacists from Franche-Comté regarding the influenza vaccination done at community pharmacies, given the proviso that they were given relevant training and allocated adequate resources.

COVID-19 outbreak: a potential threat to routine vaccination programme activities in Nigeria.

COVID-19 is an infectious disease caused by the most recently discovered coronavirus (SARS-CoV-2). The virus and disease were unknown before the outbreak began in the city of Wuhan, China, in December 2019. Nigeria and other sub-Sahara Africa countries like the rest of the world introduced several lockdown measures as part of their public health response to mitigate the spread of the virus. This, however, was not without the likelihood of consequences considering the weak health systems. The access and supply side of vaccination was more likely to have been affected by the lockdown measures. When vaccination services are disrupted even for brief periods during emergencies, the risk of outbreak-prone vaccine-preventable diseases increases, leading to excess morbidity and mortality. This highlights the importance of maintaining essential services such as vaccination in times of emergency. There is therefore an urgent need to ensure that children are protected against those diseases for which vaccines already exist. The COVID-19 outbreak has posed a new hindrance to vaccination activities in Nigeria and across Sub-Saharan Africa with associated threat to surveillance of vaccine-preventable diseases. Achieving and sustaining high levels of vaccination coverage during this period must, therefore, be a priority for all health systems.

Distemper, extinction, and vaccination of the Amur tiger.

Canine distemper virus (CDV) has recently emerged as an extinction threat for the endangered Amur tiger (Panthera tigris altaica). CDV is vaccine-preventable, and control strategies could require vaccination of domestic dogs and/or wildlife populations. However, vaccination of endangered wildlife remains controversial, which has led to a focus on interventions in domestic dogs, often assumed to be the source of infection. Effective decision making requires an understanding of the true reservoir dynamics, which poses substantial challenges in remote areas with diverse host communities. We carried out serological, demographic, and phylogenetic studies of dog and wildlife populations in the Russian Far East to show that a number of wildlife species are more important than dogs, both in maintaining CDV and as sources of infection for tigers. Critically, therefore, because CDV circulates among multiple wildlife sources, dog vaccination alone would not be effective at protecting tigers. We show, however, that low-coverage vaccination of tigers themselves is feasible and would produce substantive reductions in extinction risks. Vaccination of endangered wildlife provides a valuable component of conservation strategies for endangered species.