Estimating the effectiveness of vaccine programs in dog populations

Abstract 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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Modeling vaccination strategies in an Excel spreadsheet: Increasing the rate of vaccination is more effective than increasing the vaccination coverage for containing COVID-19

PLoS ONE ◽

10.1371/journal.pone.0254430 ◽

2021 ◽

Vol 16 (7) ◽

pp. e0254430

Author(s):

Mario Moisés Alvarez ◽

Sergio Bravo-González ◽

Grissel Trujillo-de Santiago

Keyword(s):

Simple Model ◽

Vaccination Coverage ◽

Urban Areas ◽

Local Governments ◽

Rational Design ◽

Cost Effective ◽

Excel Spreadsheet ◽

Social Distancing ◽

Vaccination Strategies ◽

Vaccination Campaigns

We have investigated the importance of the rate of vaccination to contain COVID-19 in urban areas. We used an extremely simple epidemiological model that is amenable to implementation in an Excel spreadsheet and includes the demographics of social distancing, efficacy of massive testing and quarantine, and coverage and rate of vaccination as the main parameters to model the progression of COVID-19 pandemics in densely populated urban areas. Our model predicts that effective containment of pandemic progression in densely populated cities would be more effectively achieved by vaccination campaigns that consider the fast distribution and application of vaccines (i.e., 50% coverage in 6 months) while social distancing measures are still in place. Our results suggest that the rate of vaccination is more important than the overall vaccination coverage for containing COVID-19. In addition, our modeling indicates that widespread testing and quarantining of infected subjects would greatly benefit the success of vaccination campaigns. We envision this simple model as a friendly, readily accessible, and cost-effective tool for assisting health officials and local governments in the rational design/planning of vaccination strategies.

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Modeling the effect of vaccination strategies in an Excel spreadsheet: The rate of vaccination, and not only the vaccination coverage, is a determinant for containing COVID-19 in urban areas

10.1101/2021.01.06.21249365 ◽

2021 ◽

Author(s):

Mario Moises Alvarez ◽

Sergio Bravo-Gonzalez ◽

Grissel Trujillo-de Santiago

Keyword(s):

Simple Model ◽

Vaccination Coverage ◽

Urban Areas ◽

Local Governments ◽

Rational Design ◽

Cost Effective ◽

Excel Spreadsheet ◽

Social Distancing ◽

Vaccination Strategies ◽

Vaccination Campaigns

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Maximization of Livestock Anthrax Vaccination Coverage in Bangladesh: An Alternative Approach

Vaccines ◽

10.3390/vaccines8030435 ◽

2020 ◽

Vol 8 (3) ◽

pp. 435

Author(s):

M. Shahjahan A. Sarker ◽

Mohamed E. El Zowalaty ◽

M. Ahosanul Haque Shahid ◽

M. Asaduzzaman Sarker ◽

M. Bahanur Rahman ◽

...

Keyword(s):

Vaccination Coverage ◽

Mass Vaccination ◽

Vaccination Program ◽

Cattle Population ◽

Focus Group Discussions ◽

Group Discussions ◽

Vaccination Programs ◽

Alternative Approach ◽

Vaccination Campaigns ◽

Livestock Census

Low vaccination coverage of livestock is one of the major challenges to control anthrax in Bangladesh. This study was conducted to assess an alternate approach to maximize vaccination coverage. The method included traditional vaccination campaigns, livestock census, interviews, focus group discussions of cattle farmers, vaccination and livestock personnel, and validation workshops. It was observed that a mass vaccination program covered only 44% of the cattle population. It was found that 54.1% of the respondents did not bring their cattle to mass vaccination programs due to the difficulties of handling cattle and that there was no male member in the household. Only 12.5% of respondents acknowledged that they were not aware of the vaccine, and 3% of the respondents claimed that they ignored vaccination due to cost. All of the respondents from livestock personnel agreed that manpower was not enough to cover the total area. Further, 20% of vaccinators mentioned that they did not get enough vaccines. For an effective vaccination program, 58.33% of respondents recommended door-to-door service, and 54.16% of respondents suggested to arrange regular vaccination campaigns in six-month intervals. Thus, regular campaigns with door-to-door vaccination services are suggested to control anthrax outbreaks in Bangladesh.

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New Rabies Vaccines for Use in Humans

Vaccines ◽

10.3390/vaccines7020054 ◽

2019 ◽

Vol 7 (2) ◽

pp. 54 ◽

Cited By ~ 5

Author(s):

Hildegund C. J. Ertl

Keyword(s):

Cost Effective ◽

Central American ◽

Human Rabies ◽

Clinical Testing ◽

Vaccination Programs ◽

Rabies Control ◽

Surveillance Programs ◽

Vaccination Campaigns ◽

Animal Vaccination ◽

Rabid Animal

Although vaccines are available, rabies still claims more than 55,000 human lives each year. In most cases, rabies vaccines are given to humans after their exposure to a rabid animal; pre-exposure vaccination is largely reserved for humans at high risk for contacts with the virus. Most cases of human rabies are transmitted by dogs. Dog rabies control by mass canine vaccination campaigns combined with intensive surveillance programs has led to a decline of human rabies in many countries but has been unsuccessful in others. Animal vaccination programs are also not suited to control human rabies caused by bat transmission, which is common in some Central American countries. Alternatively, or in addition, more widespread pre-exposure vaccination, especially in highly endemic remote areas, could be implemented. With the multiple dose regimens of current vaccines, pre-exposure vaccination is not cost effective for most countries and this warrants the development of new rabies vaccines, which are as safe as current vaccines, but achieve protective immunity after a single dose, and most importantly, are less costly. This chapter discusses novel rabies vaccines that are in late stage pre-clinical testing or have undergone clinical testing and their potential for replacing current vaccines.

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BRaVE Project: processing an evidence-based tool to develop and evaluate vaccination strategies

European Journal of Public Health ◽

10.1093/eurpub/ckaa165.038 ◽

2020 ◽

Vol 30 (Supplement_5) ◽

Author(s):

E Carini ◽

G E Calabrò ◽

A Tognetto ◽

S Mancinelli ◽

L Sarnari ◽

...

Keyword(s):

Vaccination Coverage ◽

Vaccination Strategy ◽

Evidence Based ◽

Organizational Strategies ◽

Vaccine Preventable Diseases ◽

Face To Face ◽

Vaccination Strategies ◽

The Face ◽

Original Grid ◽

New Strategies

Abstract Introduction Deaths and epidemics due to vaccine-preventable diseases still occur even though there are effective vaccines available. Albeit recommendations released by the Italian Ministry of Health, vaccination coverages remain unsatisfactory. An improvement is therefore needed and new strategies are deserved in order to increase coverage. Nevertheless, neither a validated tool nor an institutional guideline to plan and/or evaluate vaccination strategies are available. The aim of BRaVE project was to build an evidence-based tool to develop and assess them. Methods In May 2019, a scoping review in MEDLINE and a search of ECDC and WHO websites were performed to look for validated tools to plan and/or evaluate vaccination strategies. The results of the search and the four phases of the Deming cycle (Plan, Do, Check, Act) were used to develop a grid. A multiprofessional panel of 7 experts validated the items included in the grid through a Delphi process followed by a face-to-face meeting. Results The original grid submitted to the panel of experts included 30 items (13 planning, 7 implementation, 4 check, 4 act, 2 other). The first round of Delphi led to the suggestion of 11 additional items and to the amendment of 4 out of 30 original items. During the second round of the Delphi the 41 items proposed were approved. At the end of the face-to-face meeting, 1 item was split. Seven items belonging to “Planning” (Plan) and “Implementation” (Do) were labelled as requisites for launching a vaccination strategy and the remaining 35 as items to be considered in their evaluation (15 planning, 11 implementation, 8 check, 4 act, 4 other). Conclusions Despite its importance, vaccination coverage is low. Evidence shows possible improvement in coverage, if innovative vaccination strategies are put in place. The developed grid is proposed as an organizational instrument which could improve and standardize vaccination strategies fostering their success and transferability. Key messages Novel organizational strategies could be a useful answer to improve vaccination coverage. The proposed grid could be used for the development and assessment of vaccination strategies.

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Using Novel, Agent-Based Periodic Mobility Model with Super Spreaders to Analyze Vaccination Strategies for COVID-19

10.1101/2021.08.09.21261809 ◽

2021 ◽

Author(s):

Mathew K Jacob ◽

Eva Xueyao Guo

Keyword(s):

Vaccination Strategy ◽

Human Movement ◽

The Elderly ◽

Mobility Model ◽

Limited Resources ◽

Agent Based ◽

Vaccination Strategies ◽

Periodic Movement ◽

Vaccine Availability ◽

Novel Agent

Background: With the innovation of vaccines to fight against the COVID-19 pandemic, following an effective vaccination strategy is crucial in mitigating deaths and hospitalizations and offering the greatest protection to a community or locality within the early months of vaccine-availability, when resources may be scarce. By using a novel agent-based periodic mobility model that captures periodic movement, which attempts to model human movement patterns, super spreaders, and ICU hospitalizations, this study attempts to find the best strategy for vaccinating individuals to mitigate the damage of COVID-19. Results: This study found that a vaccination strategy that first vaccinates the elderly would be most effective at mitigating deaths and lowering the ICU hospitalization peak during the first two months of vaccine rollout. Conclusion: For communities that are early in their vaccine campaign or that have limited resources for vaccination, we recommend that they prioritize vaccinating the elderly who are more susceptible to COVID-19 first.

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The impact of COVID-19 vaccination campaigns accounting for antibody-dependent enhancement

PLoS ONE ◽

10.1371/journal.pone.0245417 ◽

2021 ◽

Vol 16 (4) ◽

pp. e0245417

Author(s):

Nessma Adil Mahmoud Yousif ◽

Henri Christian Junior Tsoungui Obama ◽

Yvan Jordan Ngucho Mbeutchou ◽

Sandy Frank Kwamou Ngaha ◽

Loyce Kayanula ◽

...

Keyword(s):

Vaccination Coverage ◽

Disease Incidence ◽

Case Fatality ◽

Decision Support Tool ◽

Economic Damage ◽

Support Tool ◽

Antibody Dependent Enhancement ◽

Vaccination Strategies ◽

Vaccination Campaigns ◽

The Impact

Background COVID-19 vaccines are approved, vaccination campaigns are launched, and worldwide return to normality seems within close reach. Nevertheless, concerns about the safety of COVID-19 vaccines arose, due to their fast emergency approval. In fact, the problem of antibody-dependent enhancement was raised in the context of COVID-19 vaccines. Methods and findings We introduce a complex extension of the model underlying the pandemic preparedness tool CovidSim 1.1 (http://covidsim.eu/) to optimize vaccination strategies with regard to the onset of campaigns, vaccination coverage, vaccination schedules, vaccination rates, and efficiency of vaccines. Vaccines are not assumed to immunize perfectly. Some individuals fail to immunize, some reach only partial immunity, and—importantly—some develop antibody-dependent enhancement, which increases the likelihood of developing symptomatic and severe episodes (associated with higher case fatality) upon infection. Only a fraction of the population will be vaccinated, reflecting vaccination hesitancy or contraindications. The model is intended to facilitate decision making by exploring ranges of parameters rather than to be fitted by empirical data. We parameterized the model to reflect the situation in Germany and predict increasing incidence (and prevalence) in early 2021 followed by a decline by summer. Assuming contact reductions (curfews, social distancing, etc.) to be lifted in summer, disease incidence will peak again. Fast vaccine deployment contributes to reduce disease incidence in the first quarter of 2021, and delay the epidemic outbreak after the summer season. Higher vaccination coverage results in a delayed and reduced epidemic peak. A coverage of 75%–80% is necessary to prevent an epidemic peak without further drastic contact reductions. Conclusions With the vaccine becoming available, compliance with contact reductions is likely to fade. To prevent further economic damage from COVID-19, high levels of immunization need to be reached before next year’s flu season, and vaccination strategies and disease management need to be flexibly adjusted. The predictive model can serve as a refined decision support tool for COVID-19 management.

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Pneumococcal Serotype Identification by Capsular Sequence Typing (CST): A Modified Novel Approach for Serotyping Directly in Clinical Samples

Diagnostics ◽

10.3390/diagnostics11122353 ◽

2021 ◽

Vol 11 (12) ◽

pp. 2353

Author(s):

Nektarios Marmaras ◽

Athanasia Xirogianni ◽

Anastasia Papandreou ◽

Efthymia Petinaki ◽

Vana Papaevangelou ◽

...

Keyword(s):

Vaccination Strategy ◽

Cost Effective ◽

Clinical Samples ◽

Pneumococcal Serotypes ◽

Conjugate Vaccines ◽

Vaccination Programs ◽

Epidemiological Monitoring ◽

Novel Approach ◽

Cost Effective Method ◽

Serotype Identification

As almost 60–70% of Invasive Pneumococcal Disease (IPD) is identified by nonculture methods in Greece, serotyping is of high importance for the better monitoring of pneumococcal serotypes due to the availability of conjugate vaccines. The aim of the study was the modification and direct application of the Capsular Sequence Typing (CST) assay in clinical samples in order to serotype Streptococcus pneumoniae culture-negative, Polymerase Chain Reaction (PCR_-positive samples, followed by CST group specific single-tube PCR assays. A two-step PCR modified assay was applied on a total of 306 samples (such as CSF, blood, pleural and middle ear fluids, isolates) obtained from 283 patients with IPD. The overall performance permits a rapid, accurate and cost-effective method for nonculture pneumococcal serotyping. As the management of IPD is closely related to the continuous monitoring of pneumococcal serotypes, the proposed approach proved to be a valuable tool for the typing and epidemiological monitoring of S. pneumoniae, for the evaluation of the overall impact of vaccination programs in the era of pneumococcal conjugate vaccines, in order to initiate the appropriate vaccination strategy.

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The impact of COVID-19 vaccination campaigns accounting for antibody-dependent enhancement

10.1101/2021.01.04.425198 ◽

2021 ◽

Author(s):

Nessma Adil M. Y. ◽

Henri Christian Junior Tsoungui Obama ◽

Jordan Ngucho Yvan Mbeutchou ◽

Sandy Frank Kwamou Ngaha ◽

Loyce Kayanula ◽

...

Keyword(s):

Vaccination Coverage ◽

Disease Incidence ◽

Case Fatality ◽

Decision Support Tool ◽

Economic Damage ◽

Support Tool ◽

Antibody Dependent Enhancement ◽

Vaccination Strategies ◽

Vaccination Campaigns ◽

The Impact

Background: COVID-19 vaccines are approved, vaccination campaigns are launched, and worldwide return to normality seems within close reach. Nevertheless, concerns about the safety of COVID-19 vaccines arose, due to their fast emergency approval. In fact, the problem of antibody-dependent enhancement was raised in the context of COVID-19 vaccines. Methods and findings: We introduce a complex extension of the model underlying the pandemic preparedness tool CovidSim 1.1 (http://covidsim.eu/) to optimize vaccination strategies with regard to the onset of campaigns, vaccination coverage, vaccination schedules, vaccination rates, and efficiency of vaccines. Vaccines are not assumed to immunize perfectly. Some individuals fail to immunize, some reach only partial immunity, and -- importantly -- some develop antibody-dependent enhancement, which increases the likelihood of developing symptomatic and severe episodes (associated with higher case fatality) upon infection. Only a fraction of the population will be vaccinated, reflecting vaccination hesitancy or contraindications. We parameterized the model to reflect the situation in Germany and predict increasing incidence (and prevalence) in early 2021 followed by a decline by summer. Assuming contact reductions (curfews, social distancing, etc.) to be lifted in summer, disease incidence will peak again. Fast vaccine deployment contributes to reduce disease incidence in the first quarter of 2021, and delay the epidemic outbreak after the summer season. Higher vaccination coverage results in a delayed and reduced epidemic peak. A coverage of 75% - 80% is necessary to prevent an epidemic peak without further drastic contact reductions. Conclusions: With the vaccine becoming available, compliance with contact reductions is likely to fade. To prevent further economic damage from COVID-19, high levels of immunization need to be reached before next year's flu season, and vaccination strategies and disease management need to be flexibly adjusted. The predictive model can serve as a refined decision support tool for COVID-19 management.

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Comparison of vaccination strategies for the control of dog rabies in Machakos District, Kenya

Epidemiology and Infection ◽

10.1017/s0950268802006957 ◽

2002 ◽

Vol 129 (1) ◽

pp. 215-222 ◽

Cited By ~ 62

Author(s):

P. M. KITALA ◽

J. J. McDERMOTT ◽

P. G. COLEMAN ◽

C. DYE

Keyword(s):

Field Data ◽

Deterministic Model ◽

Reproduction Number ◽

Vaccination Rate ◽

Confidence Limits ◽

Vaccination Strategies ◽

Model Predictions ◽

The Stability ◽

Vaccination Campaigns ◽

The Impact

Demographic and epidemiological field data were used in a deterministic model to describe dog rabies transmission in Machakos District, Kenya and to predict the impact of potential vaccination strategies for its control. The basic reproduction number (R0) was estimated to be 2.44 (1.52–3.36, 95% confidence limits). There were three key model predictions. The first was that a threshold dog density (KT) of 4.5 dogs km−2 (3.8–5.2 dogs km−2, 95% confidence limits) was required to maintain transmission. The second was that the estimated annual vaccination rate of 24% failed to decrease incidence and actually increased the stability of transmission and may be counter-productive. Thirdly, to control rabies, it was predicted that 59% (34%–70%, 95% confidence limits) of dogs should be vaccinated at any one time. This requires approximately 70% coverage for annual but only 60% coverage for semi-annual vaccination campaigns. Community-level vaccination trials are needed to test these predictions.

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