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Objective: Mathematical models are vital tools to understand transmission dynamics and assess the impact of interventions to mitigate COVID‐19. However, historically, their use in Africa has been limited. In this scoping review, we assess how mathematical models were used to study COVID‐19 vaccination to potentially inform pandemic planning and response in Africa. Methods: We searched six electronic databases: MEDLINE, Embase, Web of Science, Global Health, MathSciNet and Africa‐Wide NiPAD, using keywords to identify articles focused on the use of mathematical modelling studies of COVID‐19 vaccination in Africa that were published as of October 2022. We extracted the details on the country, author affiliation, characteristics of models, policy intent and heterogeneity factors. We assessed quality using 21‐point scale criteria on model characteristics and content of the studies. Results: The literature search yielded 462 articles, of which 32 were included based on the eligibility criteria. Nineteen (59%) studies had a first author affiliated with an African country. Of the 32 included studies, 30 (94%) were compartmental models. By country, most studies were about or included South Africa (n = 12, 37%), followed by Morocco (n = 6, 19%) and Ethiopia (n = 5, 16%). Most studies (n = 19, 59%) assessed the impact of increasing vaccination coverage on COVID‐19 burden. Half (n = 16, 50%) had policy intent: prioritising or selecting interventions, pandemic planning and response, vaccine distribution and optimisation strategies and understanding transmission dynamics of COVID‐19. Fourteen studies (44%) were of medium quality and eight (25%) were of high quality. Conclusions: While decision‐makers could draw vital insights from the evidence generated from mathematical modelling to inform policy, we found that there was limited use of such models exploring vaccination impacts for COVID‐19 in Africa. The disparity can be addressed by scaling up mathematical modelling training, increasing collaborative opportunities between modellers and policymakers, and increasing access to funding. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID-19) pandemic is a global threat, challenging health services' provision and utilization. This study aimed to assess compulsory vaccination coverage in 12 Sub-Saharan African countries two years following the COVID-19 pandemic using the Health Belief Model. A cross-sectional survey was conducted from November 1 to December 15, 2022. Multivariate logistic regression was conducted to identify the determinants of vaccination coverage. Among the 5032 respondents, 73.1% reported that their children received compulsory vaccination. The lowest coverage was observed in Ghana (36.5%), while the highest was in Burkina Faso and Congo (92.0%). Factors associated with non-vaccination included older mothers (adjusted odds ratio (AOR) = 1.04, 95%CI: 1.03–1.05), lower mothers' education, older children (AOR = 0.76, 95%CI: 0.60–0.96), children with chronic illnesses (AOR = 0.55, 95%CI: 0.45–0.66), and difficult accessibility to healthcare facilities (AOR = 11.27, 95%CI: 9.48–13.44). Low perceived risk, in which non-vaccinated children were believed to be at no higher risk for infectious diseases and the disease severity would not worsen among non-vaccinated children, increased the likelihood of non-vaccination (AOR = 2.29, 95%CI: 1.75–2.99 and AOR = 2.12, 95%CI: 1.64–2.73, respectively). Perceiving vaccines as unnecessary, and needless for breastfed babies increased the probability of non-vaccination (AOR = 1.38, 95%CI: 1.10–1.73 and AOR = 1.69, 95%CI: 1.31–2.19, respectively). Higher odds of non-vaccination were found when the provision of vaccine information did not motivate parents to vaccinate their children (AOR = 4.29, 95%CI: 3.15–5.85). Conversely, believing that vaccines were safe for children decreased the odds of non-vaccination (AOR = 0.72, 95%CI: 0.58–0.88). Parental perceptions and concerns should be considered in interventions aiming to increase compulsory vaccine acceptance and coverage. [ABSTRACT FROM AUTHOR]

Background: The persistently high out-of-pocket health spending (OOPHE) in Africa raise significant concern about the prospect of reaching SDG health targets and UHC. The study examines the convergence hypothesis of OOPHE in 40 African countries from 2000 to 2019. Methods: We exploit the log t , club clustering, and merging methods on a panel of dataset obtained from the World Development Indicators, the World Governance Indicators, and the World Health Organization. Then, we employ the multilevel linear mixed effect model to examine whether countries' macro-level characteristics affect the disparities in OOPHE in the African regional economic communities (RECs). Results: The results show evidence of full panel divergence, indicating persistent disparities in OOPHE over time. However, we found three convergence clubs and a divergent group for the OOPHE per capita and as a share of the total health expenditure. The results also show that convergence does not only occur among countries affiliated with the same regional economic grouping, suggesting disparities within the regional groupings. The findings reveal that countries' improved access to sanitation and quality of governance, increased childhood DPT immunization coverage, increased share of the elderly population, life expectancy at birth, external health expenditure per capita, and ICT (information and communication technology) significantly affect within-regional groupings' disparities in OOPHE per capita. The results also show that an increasing countries' share of elderly and younger populations, access to basic sanitation, ICT, trade GDP per capita, life expectancy at birth, childhood DPT immunization coverage, and antiretroviral therapy coverage have significant impacts on the share of OOPHE to total health expenditure within the regional groupings. Conclusion: Therefore, there is a need to develop policies that vary across the convergence clubs. These countries should increase their health services coverage, adopt planned urbanization, and coordinate trade and ICT access policies. Policymakers should consider hidden costs associated with access to childhood immunization services that may lead to catastrophic health spending. [ABSTRACT FROM AUTHOR]

Background: Vaccine inequity is a reality facing the Sub-Saharan Africa region as vaccine nationalism from high-income countries (HICs) leads to limited access to the lifesaving vaccines needed to end the pandemic. In Africa, a significant portion of the population has yet to be vaccinated against Covid-19; however, the barriers to accessing such vaccines, including capacity challenges, still persist despite the implementation of the COVAX facility meant to support the lower- and middle-income countries (LMICs) to boost vaccination. Methods: This study involved a systemic narrative review where literature search was conducted using the NCBI's PMC and BMC databases based on defined keywords. Three authors were involved in the literature search and consensus was applied to settle disagreements and validate the findings. Results: In this systematic narrative review, we report that vaccine nationalism remains a challenge for LMICs as HICs still hoard vaccines and even bypass COVAX to procure doses directly from the manufacturers. Factors that promote vaccine hesitancy in Africa include misinformation regarding the Covid-19 vaccine, a lack of trust in politicians and the pharmaceutical industry, and concerns about vaccine safety and efficacy. The policies implemented to enhance vaccine coverage in Africa, such as mandates, community engagement, and partnerships, all seek to promote equity of vaccination and ending Covid-19. Conclusion: Covid-19 vaccine inequity persists and contributes to prolonged pandemic in LMICs. In response, African governments have taken certain measures to enhance vaccine uptake but more needs to be done to address resistance to vaccines. [ABSTRACT FROM AUTHOR]

• There is a global need for broadly protective group A streptococcal vaccines. • M protein-based subunit vaccines elicit M-type cross-reactive antibodies. • Structure-based design of multivalent vaccines improves potential coverage. • A 32-valent vaccine could prevent the majority of group A streptococcal infections. The M protein of group A streptococci (Strep A) is a major virulence determinant and protective antigen. The N-terminal region of the M protein is variable in sequence, defines the M/emm type, and contains epitopes that elicit opsonic antibodies that protect animals from challenge infections. Although there are >200 M types of Strep A, there is now evidence that structurally related M proteins can be grouped into clusters and that immunity may be cluster-specific in addition to M type-specific. This observation has led to recent studies of structure-based design of multivalent M peptide vaccines to select peptides predicted to cross-react with heterologous M types to improve vaccine coverage. In the current study, we have applied a refined series of peptide structural algorithms to predict immunological cross-reactivity among 117 N-terminal M peptides representing the most prevalent M types of Strep A. Based on the results of the structural analyses, in combination with global M type prevalence data, we constructed a 32-valent vaccine containing 19 cross-reactive vaccine candidates predicted to cross-react with 37 heterologous M peptides to which were added 13 type-specific M peptides. The 4-protein recombinant vaccine was immunogenic in rabbits and elicited significant levels of antibodies against 31/32 (97%) vaccine peptides and 28/37 (76%) peptides predicted to cross-react. The vaccine antisera also promoted opsonophagocytic killing of vaccine and cross-reactive M types of Strep A. Based on a recent analysis of M type prevalence of Strep A, the potential global coverage of the 32-valent vaccine is ∼90%, ranging from 68% in Africa to 95% in North America. Our results indicate the utility of structure-based design that may be applied to future studies of broadly protective M peptide vaccines. [ABSTRACT FROM AUTHOR]

Objectives: The Coronavirus Disease 2019 (COVID-19) vaccine coverage rates for various countries were analyzed to observe how the rates varied across continents as of May 6, 2023. We also aimed to determine their correlation with COVID-19 statistics (cases/fatalities/tests). Methods: The "Our World in Data" website was searched to extract the vaccine coverage rates as of 1 July 2021, 1 January 2022, 1 July 2022, 1 January 2023, and 6 May 2023 for each country included in the study. Data on COVID-19 were obtained from the "Worldometer" website. Statistics were presented both cumulatively and yearly. Results: This analysis included 180 countries. The analysis of variance test showed a statistically significant difference in the COVID-19 vaccine coverage rates and COVID-19 data, except for the Case-fatality rate (CFR), between continents, with Africa having the lowest. The Independent t-test showed that countries with 50% or higher vaccination coverage had higher rates of cases, deaths, and tests but a lower CFR in 2022, higher median age, and higher Gross Domestic Product. Similarly, in early 2023 (till May 5), there was a notable difference in the rate of cases and deaths. Furthermore, there was a clear positive correlation between vaccine coverage rates and all other data, except for CFRs, which had a negative correlation. Conclusions: Inconsistencies in COVID-19 data, including vaccination coverage, across continents emphasize the importance of establishing uniform standards for identifying and diagnosing cases, ensuring fair vaccine distribution, and equipping all countries with essential diagnostic resources to prepare for future emergencies. [ABSTRACT FROM AUTHOR]

Objectives: Africa has become the focus of attention of the world, as it has been the least affected continent by the Coronavirus-19 Disease (COVID-19) pandemic. This study used COVID-19 data to examine the COVID-19 prevalence across Africa by the end of 2022 based on income and geographic division. Methods: COVID-19 data, including the vaccination coverage rates, for each African country, were obtained from well-known publicly online websites. The analysis of variance (ANOVA) test and an Independent Samples t-Test was used to determine how much COVID-19 differs across the continent. Results: By the end of 2022, Africa's share of global COVID-19 cases, deaths, and tests was 1.92%, 3.85%, and 1.62%, respectively. There was a significant difference in the means of median age, the vaccination coverage rate (the 2021 end), cases per million, deaths per million, and tests per population where low-income African countries had lower values than middle-income ones. Across Africa's five regions, Southern Africa was the most affected. In contrast, Central Africa was the least affected, with 2,337 cases per million and 35 deaths per million. Conclusions: Although the impact of the COVID-19 pandemic on Africa was the least compared to other continents, the impact across Africa has been inconsistent. Low-income African countries were affected less than middle-income African countries. Moreover, COVID-19 statistics were uneven across the five parts of Africa. The inadequate testing capacity possibly plays an essential role in such inconsistency. Africa's experience with the COVID-19 pandemic must remain an open book to document mistakes made and lessons learned. [ABSTRACT FROM AUTHOR]

Whilst the largely limited health system and funds are already overstretched while responding to multiple epidemics, ongoing vaccine-preventable diseases (VPD) including polio and measles continue to be a public health threat and expose the weaknesses of the public health system in many African countries. The surge in VPD outbreaks during epidemics appears to be a common trend in Africa, often due to reduced vaccination coverage. The World Health Organization reported that, in 2021, nearly 25 million children missed their first measles dose, 5 million more than in 2019. The drop in childhood immunizations was partly attributed to the COVID-19 pandemic which has caused significant interruption in public health services delivery and reduced vaccination coverage. Vaccines help reduce the incidence of VPD. Therefore, effective VPD outbreak response mechanisms and strategies that include ramping up catch-up campaigns for immunization during epidemic troughs including the provision of vaccines outside clinics as well as assessing newer vaccine delivery models during pandemics are essential to minimize the impact of VPD outbreaks during emerging epidemics. Ensuring access to vaccines to address outbreaks and provide supplemental vaccination is essential if we are to be a VPD-free region. [ABSTRACT FROM AUTHOR]

Africa bears the brunt of diarrheal mortality globally. Rotavirus vaccination rates are high across the continent and demonstrate impact on diarrheal disease reduction. Nevertheless, there is room for significant improvement in managing rotavirus vaccine coverage, in access to recognized public services such as appropriate medical care, including oral rehydration therapy and improved water and sanitation. [ABSTRACT FROM AUTHOR]

Historical cultural practices that no longer exist can have modern day effects. Because communism has been linked with distrust of government, it was hypothesized that (a) historical communism would be negatively associated with COVID-19 vaccination rates, and (b) trust in government would mediate the association. Two studies assessed these hypotheses. Study 1 tested the hypotheses among European, Asian, and African countries, while Study 2 focused on East and West Germany within Europe. All samples except Africa found support for an association between historical communism and lower COVID-19 vaccination rates. However, trust in government did not mediate the association in Study 1, though a significant indirect effect did emerge within Germany in Study 2. Associations held controlling for GDP and age of population. Together, the studies suggest that historical communism in Europe and Asia is associated with real-world behavior today, and that trust in government might be partly responsible for the effect within Germany but less likely within Europe as a whole. [ABSTRACT FROM AUTHOR]

Despite vaccination being one of the most effective public health interventions, there are persisting inequalities and inequities in immunisation. Understanding the differences in subnational vaccine impact can help improve delivery mechanisms and policy. We analyse subnational vaccination coverage of measles first-dose (MCV1) and estimate patterns of inequalities in impact, represented as deaths averted, across 45 countries in Africa. We also evaluate how much this impact would improve under more equitable vaccination coverage scenarios. Using coverage data for MCV1 from 2000–2019, we estimate the number of deaths averted at the first administrative level. We use the ratio of deaths averted per vaccination from two mathematical models to extrapolate the impact at a subnational level. Next, we calculate inequality for each country, measuring the spread of deaths averted across its regions, accounting for differences in population. Finally, using three more equitable vaccination coverage scenarios, we evaluate how much impact of MCV1 immunisation could improve by (1) assuming all regions in a country have at least national coverage, (2) assuming all regions have the observed maximum coverage; and (3) assuming all regions have at least 80% coverage. Our results show that progress in coverage and reducing inequality has slowed in the last decade in many African countries. Under the three scenarios, a significant number of additional deaths in children could be prevented each year; for example, under the observed maximum coverage scenario, global MCV1 coverage would improve from 76% to 90%, resulting in a further 363(95%CrI:299–482) deaths averted per 100,000 live births. This paper illustrates that estimates of the impact of MCV1 immunisation at a national level can mask subnational heterogeneity. We further show that a considerable number of deaths could be prevented by maximising equitable access in countries with high inequality when increasing the global coverage of MCV1 vaccination. [ABSTRACT FROM AUTHOR]

Background: Malaria has been strongly linked to the transmission and pathophysiology of some viral diseases. Malaria and vaccine-preventable diseases often co-exist in endemic countries but the implication of their co-existence on their transmission dynamics and control is poorly understood. The study aims to evaluate the relationships between the incidence of malaria and cases of measles and yellow fever in Africa. Methods: The malaria incidence, death due to malaria, measles and yellow fever data were sourced from the WHO database. Poisson and zero-inflated time-trend regression were used to model the relationships between malaria and the two vaccine-preventable diseases. P-values <0.05 were considered statistically significant. Results: A significant negative relationship existed between malaria incidence and measles cases (P<0.05), however, malaria showed a positive relationship with yellow fever (P<0.05). The relationships between death due to malaria and measles/yellow fever cases followed similar trends but with a higher level of statistical significance (P<0.001). Conclusions: Malaria varied negatively with measles cases but positively with yellow fever. The relationships observed in this study could be important for the management of malaria and the studied vaccine-preventable diseases. Increase vaccination coverage and/or malaria treatment could modulate the direction of these relationships. [ABSTRACT FROM AUTHOR]

The accelerated development of coronavirus disease (COVID-19) candidate vaccines is intended to achieve worldwide immunity. Ensuring COVID-19 vaccination is crucial to stemming the pandemic, reclaiming everyday life, and helping restore economies. However, challenges exist to deploying these vaccines, especially in resource-limited sub-Saharan Africa. In this article, we highlight lessons learned from previous efforts to scale up vaccine distribution and offer considerations for policymakers and key stakeholders to use for successful COVID-19 vaccination rollout in Africa. These considerations range from improving weak infrastructure for managing data and identifying adverse events after immunization to considering financing options for overcoming the logistical challenges of vaccination campaigns and generating demand for vaccine uptake. In addition, providing COVID-19 vaccination can be used to promote the adoption of universal healthcare, especially in sub-Saharan Africa countries. [ABSTRACT FROM AUTHOR]

Country of origin might affect vaccine uptake in children born to immigrants. We aimed to evaluate differences in childhood vaccination coverage (VC) and timeliness by macro-area of origin of foreign mothers residing in Italy. Multicentre retrospective birth cohorts. We analysed data of 23,287 children born in 2009–2014 to foreign women in the cities of Rome, Turin and Treviso. We retrieved data through record-linkage of the population, vaccination and birth registries. We estimated VCs at different ages for vaccines against tetanus, measles and meningococcal group-C, using the Kaplan–Meier method. Factors associated with vaccine uptake were evaluated using multilevel Poisson models. Estimates of VC at any age and for all antigens were significantly lower in children born to women from Asia and higher in children born to women from Africa, as compared to other macro-areas. Similar differences by area of origin were observed for timeliness; independently of mother's sociodemographic characteristics and neonatal outcomes, the probability of delay vaccination after 2 years of age for each antigen was highest in children born to women from Asia. The risk of missed vaccination for all antigens was significantly higher in children born to younger and unemployed women. Factors related to area of origin (e.g., cultural habits, language skills) are likely to affect parents' decision to vaccinate their children. These factors, as well as sociodemographic characteristics, should be adequately investigated and addressed to increase vaccine uptake in foreign children, especially those born to Asian women. [ABSTRACT FROM AUTHOR]

Fake vaccines trafficking is a recent but growing phenomenon, which represents a severe threat to public health. During the Covid-19 pandemic, anti-Covid vaccines have been a prime target for traffickers, but all types of vaccines are falsified by profit-hungry criminals. The consequences of falsification on global health are serious: decline in vaccination coverage, loss of control of epidemics which will claim yet more victims, and resurgence of diseases that were under control. Fake vaccines also fuel the mistrust of populations towards science and authorities. In order to tackle this scourge, a general and coordinated mobilization of all actors concerned is urgently needed: health professionals, political decision-makers, police and customs forces, judges and prosecutors, without forgetting the crucial awareness-raising of public opinion. [ABSTRACT FROM AUTHOR]

COVID-19 continues to strain, stress, and stretch health systems globally. With the development of the COVID-19 vaccines, there are many issues still lurking behind the widespread coverage; one of which is COVID-19 vaccine nationalism and African countries are not exempted from these issues. This is evident in that many countries in the African region missed the earlier targets set by World Health Organization (WHO) for COVID-19 vaccination coverage. The WHO further set a target of 70% coverage of the COVID-19 vaccines for all countries by June 2022. In this article, we discuss the possible reasons why many African countries are struggling and may not achieve the COVID-19 vaccination target in 2022. With the fundamental issues facing COVID-19 vaccination ranging from nationalism to hesitancy, it is important that stakeholders continue to work harder to ensure that the continent is not left behind in the race to keep the world free and safe from the sting of the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Adolescents refer to individuals in the age group 10 to 19 years. Vaccination of people in this age group offers an opportunity to catch-up on vaccinations missed during childhood, boost waning immunity from childhood vaccines, and provide primary immunity with new vaccines. Vaccination coverage among adolescents is suboptimal worldwide, especially in African countries, and it is unclear which interventions could improve the situation. We focus this commentary on a recent Cochrane review that assessed the effects of interventions to increase vaccination coverage among adolescents. The authors conducted a comprehensive search in multiple peer-reviewed and grey literature databases and identified 16 eligible studies, mostly conducted in high-income countries. The most effective interventions for improving adolescent vaccination coverage included: education of adolescents and their parents about the importance of vaccinations; mandatory vaccination, whereby government enacts laws requiring adolescents to be vaccinated as a pre-condition for school enrolment; and providing a complementary package of educational interventions to adolescents and their parents and healthcare workers. Implementing the evidence from this review would improve adolescent vaccination coverage in Africa. However, given that only one eligible study was conducted in an African country, there is need for African researchers to invest on research in this topic. [ABSTRACT FROM AUTHOR]

Recurrent respiratory papillomatosis (RRP) is a chronic condition caused by Human papillomavirus six (HPV-6) and HPV-11 that involves the respiratory tract. Disease severity ranges from mild (hoarseness), through to severe (stridor, respiratory distress and airway emergencies). Africa has the fastest growing and youngest population of all the continents. It also has the greatest burden of cervical cancer. There is an association with infection of the oncogenic HPV strains and the strains responsible for RRP. It is reasonable to conclude that although RRP may be underestimated in low-to-middle-income countries, it poses a considerable health risk to Africa. The primary aim of this project was to assess the suitability of HPV vaccination coverage on the African continent. A prospective study was designed to consist of an online survey. It was distributed to 135 African otolaryngologists. Questions focussed on HPV vaccination programmes; whether they were government directed; and their rollout. Information from countries that had multiple otolaryngologists respond to the survey were compared. Additionally, data review and corroboration were performed. There were 58 (43%) participants from 19 countries. Nine countries reported a national vaccination programme (NVP), five used Cervarix; four used quadrivalent Gardasil. Collateral data revealed 18 of 54 countries had NVP in Africa and 26 countries had completed HPV vaccine pilot or demonstration projects. HPV vaccination in Africa should be urgently re-evaluated to include the HPV-6 and HPV-11 strains that cause JORRP, which have not been recognised during national vaccination programme planning. [ABSTRACT FROM AUTHOR]

Background: Rabies still poses a significant human health problem throughout most of Africa, where the majority of the human cases results from dog bites. Mass dog vaccination is considered to be the most effective method to prevent rabies in humans. Our objective was to systematically review research articles on dog rabies parenteral vaccination coverage in Africa in relation to dog accessibility and vaccination cost recovery arrangement (i.e.free of charge or owner charged). Methodology/Principal Findings: A systematic literature search was made in the databases of CAB abstracts (EBSCOhost and OvidSP), Scopus, Web of Science, PubMed, Medline (EBSCOhost and OvidSP) and AJOL (African Journal Online) for peer reviewed articles on 1) rabies control, 2) dog rabies vaccination coverage and 3) dog demography in Africa. Identified articles were subsequently screened and selected using predefined selection criteria like year of publication (viz. ≥ 1990), type of study (cross sectional), objective(s) of the study (i.e. vaccination coverage rates, dog demographics and financial arrangements of vaccination costs), language of publication (English) and geographical focus (Africa). The selection process resulted in sixteen peer reviewed articles which were used to review dog demography and dog ownership status, and dog rabies vaccination coverage throughout Africa. The main review findings indicate that 1) the majority (up to 98.1%) of dogs in African countries are owned (and as such accessible), 2) puppies younger than 3 months of age constitute a considerable proportion (up to 30%) of the dog population and 3) male dogs are dominating in numbers (up to 3.6 times the female dog population). Dog rabies parenteral vaccination coverage was compared between "free of charge" and "owner charged" vaccination schemes by the technique of Meta-analysis. Results indicate that the rabies vaccination coverage following a free of charge vaccination scheme (68%) is closer to the World Health Organization recommended coverage rate (70%) than the achieved coverage rate in owner-charged dog rabies vaccination schemes (18%). Conclusions/Significance: Most dogs in Africa are owned and accessible for parenteral vaccination against rabies if the campaign is performed "free of charge". Author Summary: Rabies is one of the most fatal diseases in both humans and animals. A bite by a rabid dog is the main cause of human rabies in Africa. Parenteral mass dog vaccination is the most cost-effective tool to prevent rabies in humans. Our main objective was to review research articles on the parenteral dog rabies vaccination coverage in Africa. We aimed to review published research articles on percentage of dogs owned and percentage of dogs vaccinated against rabies, and on the relation between vaccination coverage and cost recovery. We followed the standard procedures of a systematic literature review resulting in a final review of 16 scientific articles. Our review results indicate that only a small percentage of African dogs is ownerless. Puppies younger than 3 months of age constitute a considerable proportion of the African dog population. There are considerably more male dogs than female dogs present within the dog population. The dog rabies parenteral vaccination coverage following a "free of charge" vaccination scheme (68%) is closer to World Health Organization recommended threshold coverage rate (70%) compared to the coverage rate achieved in "owner-charged" dog rabies vaccination schemes (18%). In conclusion, most dogs in Africa are owned and accessible for vaccination once the necessary financial arrangements have been made. [ABSTRACT FROM AUTHOR]

Background: Human outbreaks of Ebola virus (EBOV) are a serious human health concern in Central Africa. Great apes (gorillas/chimpanzees) are an important source of EBOV transmission to humans due to increased hunting of wildlife including the 'bush-meat' trade. Cytomegalovirus (CMV) is an highly immunogenic virus that has shown recent utility as a vaccine platform. CMV-based vaccines also have the unique potential to re-infect and disseminate through target populations regardless of prior CMV immunity, which may be ideal for achieving high vaccine coverage in inaccessible populations such as great apes. Methodology/Principal Findings: We hypothesize that a vaccine strategy using CMV-based vectors expressing EBOV antigens may be ideally suited for use in inaccessible wildlife populations. To establish a 'proof-of-concept' for CMV-based vaccines against EBOV, we constructed a mouse CMV (MCMV) vector expressing a CD8+ T cell epitope from the nucleoprotein (NP) of Zaire ebolavirus (ZEBOV) (MCMV/ZEBOV-NPCTL). MCMV/ZEBOV-NPCTL induced high levels of long-lasting (>8 months) CD8+ T cells against ZEBOV NP in mice. Importantly, all vaccinated animals were protected against lethal ZEBOV challenge. Low levels of anti-ZEBOV antibodies were only sporadically detected in vaccinated animals prior to ZEBOV challenge suggesting a role, at least in part, for T cells in protection. Conclusions/Significance: This study demonstrates the ability of a CMV-based vaccine approach to protect against an highly virulent human pathogen, and supports the potential for 'disseminating' CMV-based EBOV vaccines to prevent EBOV transmission in wildlife populations. Author Summary: Human outbreaks of hemorrhagic disease caused by Ebola virus (EBOV) are a serious health concern in Central Africa. Great apes (gorillas/chimpanzees) are an important source of EBOV transmission to humans. Candidate EBOV vaccines do not spread from the initial vaccinee. In addition to being highly immunogenic, vaccines based on the cytomegalovirus (CMV) platform have the unique potential to re-infect and disseminate through target populations. To explore the utility of CMV-based vaccines against EBOV, we constructed a mouse CMV (MCMV) vector expressing a region of nucleoprotein (NP) of Zaire ebolavirus (ZEBOV) (MCMV/ZEBOV-NPCTL). MCMV/ZEBOV-NPCTL induced high levels of long-lasting CD8+ T cells against ZEBOV NP in mice. Importantly, all vaccinated animals were protected against lethal ZEBOV challenge. The absence of ZEBOV neutralizing and only low, sporadic levels of total anti-ZEBOV IgG antibodies in protected animals prior to ZEBOV challenge indicate a role, albeit perhaps not exclusive, for CD8+ T cells in mediating protection. This study demonstrates the ability of a CMV-based vaccine approach to protect against ZEBOV, and provides a 'proof-of-concept' for the potential for a 'disseminating' CMV-based EBOV vaccine to prevent EBOV transmission in wild animal populations. [ABSTRACT FROM AUTHOR]

Background: Canine rabies causes many thousands of human deaths every year in Africa, and continues to increase throughout much of the continent. Methodology/Principal Findings: This paper identifies four common reasons given for the lack of effective canine rabies control in Africa: (a) a low priority given for disease control as a result of lack of awareness of the rabies burden; (b) epidemiological constraints such as uncertainties about the required levels of vaccination coverage and the possibility of sustained cycles of infection in wildlife; (c) operational constraints including accessibility of dogs for vaccination and insufficient knowledge of dog population sizes for planning of vaccination campaigns; and (d) limited resources for implementation of rabies surveillance and control. We address each of these issues in turn, presenting data from field studies and modelling approaches used in Tanzania, including burden of disease evaluations, detailed epidemiological studies, operational data from vaccination campaigns in different demographic and ecological settings, and economic analyses of the cost-effectiveness of dog vaccination for human rabies prevention. Conclusions/Significance: We conclude that there are no insurmountable problems to canine rabies control in most of Africa; that elimination of canine rabies is epidemiologically and practically feasible through mass vaccination of domestic dogs; and that domestic dog vaccination provides a cost-effective approach to the prevention and elimination of human rabies deaths. Author Summary: Elimination of canine rabies has been achieved in some parts of the world, but the disease still kills many thousands of people each year in Africa. Here we counter common arguments given for the lack of effective canine rabies control in Africa presenting detailed data from a range of settings. We conclude that (1) rabies substantially affects public and animal health sectors, hence regional and national priorities for control ought to be higher, (2) for practical purposes domestic dogs are the sole maintenance hosts and main source of infection for humans throughout most of Africa and Asia and sufficient levels of vaccination coverage in domestic dog populations should lead to elimination of canine rabies in most areas, (3) the vast majority of domestic dog populations across sub-Saharan Africa are accessible for vaccination with community sensitization being of paramount importance for the success of these programs, (4) improved local capacity in rabies surveillance and diagnostics will help evaluate the impact of control and elimination efforts, and (5) sustainable resources for effective dog vaccination campaigns are likely to be available through the development of intersectoral financing schemes involving both medical and veterinary sectors. [ABSTRACT FROM AUTHOR]

Objectives To analyse coverage of childhood vaccinations in a rural South African population and investigate whether maternal HIV status is associated with children’s vaccination status. Methods 2 431 children with complete information, 12–23 months of age at some point during the period January 2005 through December 2006 and resident in the Africa Centre Demographic Surveillance Area at the time of their birth were investigated. We examined the relationship between maternal HIV status and child vaccination status for five vaccinations [Bacillus Calmette-Guérin (BCG), diphtheria-tetanus-pertussis (DTP3), poliomyelitis (polio3), hepatitis B (HepB3), and measles] in multiple logistic regressions, controlling for household wealth, maternal age, maternal education and distances to roads, fixed and mobile clinics. Results Coverage of the five vaccinations ranged from 89.3% (95% CI 81.7–93.9) for BCG to 77.3% (67.1–83.6) for measles. Multivariably, maternal HIV-positive status was significantly associated with lower adjusted odds ratios (AOR) of child vaccination for all vaccines [(AOR) 0.60–0.74, all P ≤ 0.036] except measles (0.75, P = 0.073), distance to mobile clinic was negatively associated with vaccination status (all P ≤ 0.029), household wealth was positively (all P ≤ 0.013) and distance to nearest road negatively (all P ≤ 0.004) associated with vaccination status. Conclusion Positive maternal HIV status independently reduces children’s probability to receive child vaccinations, which likely contributes to the morbidity and mortality differential between children of HIV-positive and HIV-negative mothers. As a means of increasing vaccination coverage, policy makers should consider increasing the number of mobile clinics in this and similar communities in rural Africa. [ABSTRACT FROM AUTHOR]

Abstract: Effective vaccination campaigns need to reach a sufficient percentage of the population to eliminate disease and prevent future outbreaks, which for rabies is predicted to be 70%, at a cost that is economically and logistically sustainable. Domestic dog rabies has been increasing across most of sub-Saharan Africa indicating that dog vaccination programmes to date have been inadequate. We compare the effectiveness of a variety of dog vaccination strategies in terms of their cost and coverage in different community settings in rural Tanzania. Central-point (CP) vaccination was extremely effective in agro-pastoralist communities achieving a high coverage (>80%) at a low cost (US$5/dog) and inadequate (<20% coverage); combined approaches using CP and either house-to-house vaccination or trained community-based animal health workers were most effective with coverage exceeding 70%, although costs were still high (>US$6 and >US$4/dog, respectively). No single vaccination strategy is likely to be effective in all populations and therefore alternative approaches must be deployed under different settings. CP vaccination is cost-effective and efficient for the majority of dog populations in rural Tanzania and potentially elsewhere in sub-Saharan Africa, whereas a combination strategy is necessary in remote pastoralist communities. These results suggest that rabies control is logistically feasible across most of the developing world and that the annual costs of effective vaccination campaigns in Tanzania are likely to be affordable. [Copyright &y& Elsevier]