scholarly journals Introduction of rubella-containing-vaccine to Madagascar: implications for roll-out and local elimination

2016 ◽  
Vol 13 (117) ◽  
pp. 20151101 ◽  
Author(s):  
Amy Wesolowski ◽  
Keitly Mensah ◽  
Cara E. Brook ◽  
Miora Andrianjafimasy ◽  
Amy Winter ◽  
...  

Few countries in Africa currently include rubella-containing vaccination (RCV) in their immunization schedule. The Global Alliance for Vaccines Initiative (GAVI) recently opened a funding window that has motivated more widespread roll-out of RCV. As countries plan RCV introductions, an understanding of the existing burden, spatial patterns of vaccine coverage, and the impact of patterns of local extinction and reintroduction for rubella will be critical to developing effective programmes. As one of the first countries proposing RCV introduction in part with GAVI funding, Madagascar provides a powerful and timely case study. We analyse serological data from measles surveillance systems to characterize the epidemiology of rubella in Madagascar. Combining these results with data on measles vaccination delivery, we develop an age-structured model to simulate rubella vaccination scenarios and evaluate the dynamics of rubella and the burden of congenital rubella syndrome (CRS) across Madagascar. We additionally evaluate the drivers of spatial heterogeneity in age of infection to identify focal locations where vaccine surveillance should be strengthened and where challenges to successful vaccination introduction are expected. Our analyses indicate that characteristics of rubella in Madagascar are in line with global observations, with an average age of infection near 7 years, and an impact of frequent local extinction with reintroductions causing localized epidemics. Modelling results indicate that introduction of RCV into the routine programme alone may initially decrease rubella incidence but then result in cumulative increases in the burden of CRS in some regions (and transient increases in this burden in many regions). Deployment of RCV with regular supplementary campaigns will mitigate these outcomes. Results suggest that introduction of RCV offers a potential for elimination of rubella in Madagascar, but also emphasize both that targeted vaccination is likely to be a lynchpin of this success, and the public health vigilance that this introduction will require.

2009 ◽  
Vol 138 (4) ◽  
pp. 469-481 ◽  
Author(s):  
M. KARHUNEN ◽  
T. LEINO ◽  
H. SALO ◽  
I. DAVIDKIN ◽  
T. KILPI ◽  
...  

SUMMARYIt has been suggested that the incidence of herpes zoster may increase due to lack of natural boosting under large-scale vaccination with the varicella vaccine. To study the possibility and magnitude of such negative consequences of mass vaccination, we built a mathematical model of varicella and zoster epidemiology in the Finnish population. The model was based on serological data on varicella infection, case-notification data on zoster, and new knowledge about close contacts relevant to transmission of infection. According to the analysis, a childhood programme against varicella will increase the incidence of zoster by one to more than two thirds in the next 50 years. This will be due to increase in case numbers in the ⩾35 years age groups. However, high vaccine coverage and a two-dose programme will be very effective in stopping varicella transmission in the population.


2013 ◽  
Vol 368 (1623) ◽  
pp. 20120141 ◽  
Author(s):  
M. J. Ferrari ◽  
B. T. Grenfell ◽  
P. M. Strebel

The global reduction of the burden of morbidity and mortality owing to measles has been a major triumph of public health. However, the continued persistence of measles infection probably not only reflects local variation in progress towards vaccination target goals, but may also reflect local variation in dynamic processes of transmission, susceptible replenishment through births and stochastic local extinction. Dynamic models predict that vaccination should increase the mean age of infection and increase inter-annual variability in incidence. Through a comparative approach, we assess national-level patterns in the mean age of infection and measles persistence. We find that while the classic predictions do hold in general, the impact of vaccination on the age distribution of cases and stochastic fadeout are mediated by local birth rate. Thus, broad-scale vaccine coverage goals are unlikely to have the same impact on the interruption of measles transmission in all demographic settings. Indeed, these results suggest that the achievement of further measles reduction or elimination goals is likely to require programmatic and vaccine coverage goals that are tailored to local demographic conditions.


2015 ◽  
Vol 20 (7) ◽  
Author(s):  
H Levine ◽  
E Kopel ◽  
E Anis ◽  
N Givon-Lavi ◽  
R Dagan

Data on long-term impact of universal national vaccination programmes against hepatitis A are lacking. We aimed at evaluating the impact on hepatitis A incidence of the Israeli toddlers-only universal routine two-dose vaccination programme against hepatitis A initiated in 1999. All hepatitis A episodes reported to the national surveillance system from 1993 to 2012 were analysed in relation to the vaccination programme and coverage. Mean vaccine coverage in Israel between 2003 and 2010 was 92% for the first dose, given at 18 months of age, and 88% for the second dose, given at 24 months. The annual hepatitis A incidence declined from a mean of 50.4 per 100,000 in the period between 1993 and 1998 to a mean of?<1.0, during the period from 2008 to 2012, representing a reduction of?>98%. The decline was evident in all ages and ethnicity groups, including unvaccinated populations. Of the 1,247 cases reported nationwide between 2002 and 2012, the vaccination status could be ascertained in 1,108 (89%). Among them, only 20 (2%) were reported be vaccinated with one dose and three (<1%) received two doses. The sustained results of this long-term impact study suggest that a toddlers-only universal routine two-dose vaccination programme is highly effective and practical. These findings underscore the importance of sustainability in both the surveillance systems and vaccination programmes and will aid to determine vaccination policies.


2021 ◽  
Author(s):  
Ghina R Mumtaz ◽  
Fadi El-Jardali ◽  
Mathilda Jabbour ◽  
Aya Harb ◽  
Laith J Abu-Raddad ◽  
...  

Background: Amidst a very difficult economic and political situation, and after a large first SARS-CoV-2 wave near the end of 2020, Lebanon launched its vaccination campaign on 14 February 2021. To date, only 6.7% of the population have received at least one dose of the vaccine, raising serious concerns over the speed of vaccine roll-out and its impact in the event of a future surge. Objective: Using mathematical modeling, we assessed the short-term impact (by end of 2021) of various vaccine roll-out scenarios on SARS-CoV-2 epidemic course in Lebanon. Results: At current immunity levels in the population, estimated by the model at 40% on 15 April 2021, a large epidemic wave is predicted if all social distancing restrictions are gradually eased and variants of concern are introduced. Reaching 80% vaccine coverage by end of 2021 will flatten the epidemic curve and will result in a 37% and 34% decrease in the peak daily numbers of severe/critical disease cases and deaths, respectively; while reaching intermediate coverage of 40% will result in only 10-11% decrease in each. Reaching 80% coverage by end of 2021 will avert 3 times more hospitalizations and deaths over the course of this year compared with 40% coverage. Impact of vaccination was substantially enhanced with rapid scale-up. Reaching 80% vaccine coverage by August would prevent twice as many severe/critical disease cases and deaths than if it were reached by December. Finally, a longer duration over which restrictions are eased resulted in a more favorable impact of vaccination. Conclusion: For vaccination to have an impact on the predicted epidemic course and associated disease burden in Lebanon, vaccination has to be rapid and reach high coverage (at least 70%), while sustaining social distancing measures during roll-out. At current vaccination pace, this is unlikely to be achieved. Concerted efforts need to be put to overcome local challenges and substantially scale up vaccination to avoid a surge that the country, with its multiple crises and limited health-care capacity, is largely unprepared for.


2018 ◽  
Vol 146 (13) ◽  
pp. 1699-1706 ◽  
Author(s):  
Joaquin M. Prada ◽  
C. Jessica E. Metcalf ◽  
Matthew J. Ferrari

AbstractMeasles is a target for elimination in all six WHO regions by 2020, and over the last decade, there has been considerable progress towards this goal. Surveillance is recognised as a cornerstone of elimination programmes, allowing early identification of outbreaks, thus enabling control and preventing re-emergence. Fever–rash surveillance is increasingly available across WHO regions, and this symptom-based reporting is broadly used for measles surveillance. However, as measles control increases, symptom-based cases are increasingly likely to reflect infection with other diseases with similar symptoms such as rubella, which affects the same populations, and can have a similar seasonality. The WHO recommends that cases from suspected measles outbreaks be laboratory-confirmed, to identify ‘true’ cases, corresponding to measles IgM titres exceeding a threshold indicative of infection. Although serological testing for IgM has been integrated into the fever–rash surveillance systems in many countries, the logistics of sending in every suspected case are often beyond the health system's capacity. We show how age data from serologically confirmed cases can be leveraged to infer the status of non-tested samples, thus strengthening the information we can extract from symptom-based surveillance. Applying an age-specific confirmation model to data from three countries with divergent epidemiology across Africa, we identify the proportion of cases that need to be serologically tested to achieve target levels of accuracy in estimated infected numbers and discuss how this varies depending on the epidemiological context. Our analysis provides an approach to refining estimates of incidence leveraging all available data, which has the potential to improve allocation of resources, and thus contribute to rapid and efficient control of outbreaks.


2014 ◽  
Vol 143 (9) ◽  
pp. 1858-1867 ◽  
Author(s):  
B. MAO ◽  
K. CHHENG ◽  
K. WANNEMUEHLER ◽  
E. VYNNYCKY ◽  
S. BUTH ◽  
...  

SUMMARYSignificant gaps in immunity to polio, measles, and rubella may exist in adults in Cambodia and threaten vaccine-preventable disease (VPD) elimination and control goals, despite high childhood vaccination coverage. We conducted a nationwide serological survey during November–December 2012 of 2154 women aged 15–39 years to assess immunity to polio, measles, and rubella and to estimate congenital rubella syndrome (CRS) incidence. Measles and rubella antibodies were detected by IgG ELISA and polio antibodies by microneutralization testing. Age-structured catalytic models were fitted to rubella serological data to predict CRS cases. Overall, 29·8% of women lacked immunity to at least one poliovirus (PV); seroprevalence to PV1, PV2 and PV3 was 85·9%, 93·4% and 83·3%, respectively. Rubella and measles antibody seroprevalence was 73·3% and 95·9%, respectively. In the 15–19 years age group, 48·2% [95% confidence interval (CI) 42·4–54·1] were susceptible to either PV1 or PV3, and 40·3% (95% CI 33·0–47·5) to rubella virus. Based on rubella antibody seroprevalence, we estimate that >600 infants are born with CRS in Cambodia annually. Significant numbers of Cambodian women are still susceptible to polio and rubella, especially those aged 15–19 years, emphasizing the need to include adults in VPD surveillance and a potential role for vaccination strategies targeted at adults.


2019 ◽  
Vol 24 (45) ◽  
Author(s):  
Ausenda Machado ◽  
Clara Mazagatos ◽  
Frederika Dijkstra ◽  
Irina Kislaya ◽  
Alin Gherasim ◽  
...  

Background To increase the acceptability of influenza vaccine, it is important to quantify the overall benefits of the vaccination programme. Aim To assess the impact of influenza vaccination in Portugal, Spain and the Netherlands, we estimated the number of medically attended influenza-confirmed cases (MAICC) in primary care averted in the seasons 2015/16 to 2017/18 among those ≥ 65 years. Methods We used an ecological approach to estimate vaccination impact. We compared the number of observed MAICC (n) to the estimated number that would have occurred without the vaccination programme (N). To estimate N, we used: (i) MAICC estimated from influenza surveillance systems, (ii) vaccine coverage, (iii) pooled (sub)type-specific influenza vaccine effectiveness estimates for seasons 2015/16 to 2017/18, weighted by the proportion of virus circulation in each season and country. We estimated the number of MAICC averted (NAE) and the prevented fraction (PF) by the vaccination programme. Results The annual average of NAE in the population ≥ 65 years was 33, 58 and 204 MAICC per 100,000 in Portugal, Spain and the Netherlands, respectively. On average, influenza vaccination prevented 10.7%, 10.9% and 14.2% of potential influenza MAICC each season in these countries. The lowest PF was in 2016/17 (4.9–6.1%) with an NAE ranging from 24 to 69 per 100,000. Conclusions Our results suggest that influenza vaccination programmes reduced a substantial number of MAICC. Together with studies on hospitalisations and deaths averted by influenza vaccination programmes, this will contribute to the evaluation of the impact of vaccination strategies and strengthen public health communication.


Vaccines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 697
Author(s):  
Ghina R. Mumtaz ◽  
Fadi El-Jardali ◽  
Mathilda Jabbour ◽  
Aya Harb ◽  
Laith J. Abu-Raddad ◽  
...  

Four months into the SARS-CoV-2 vaccination campaign, only 10.7% of the Lebanese population have received at least one dose, raising serious concerns over the speed of vaccine roll-out and its impact in the event of a future surge. Using mathematical modeling, we assessed the short-term impact of various vaccine roll-out scenarios on SARS-CoV-2 epidemic course in Lebanon. At current population immunity levels, estimated by the model at 40% on 15 April 2021, a large epidemic wave is predicted if all social distancing restrictions are gradually eased and variants of concern are introduced. Reaching 80% vaccine coverage by the end of 2021 will flatten the epidemic curve and will result in a 37% and 34% decrease in the peak daily numbers of severe/critical disease cases and deaths, respectively; while reaching intermediate coverage of 40% will result in only a 10–11% decrease in each. Reaching 80% vaccine coverage by August would prevent twice as many severe/critical disease cases and deaths than if it were reached by December. Easing restrictions over a longer duration resulted in more favorable vaccination impact. In conclusion, for vaccination to have impact in the short-term, scale-up has to be rapid and reach high coverage (at least 70%), while sustaining social distancing measures during roll-out. At current vaccination pace, this is unlikely to be achieved. Concerted efforts need to be made to overcome local challenges and substantially scale up vaccination to avoid a surge that the country, with its multiple crises and limited health-care capacity, is largely unprepared for.


2020 ◽  
Vol 11 (SPL1) ◽  
pp. 1026-1033
Author(s):  
Nivedha Valliammai Mahalingam ◽  
Abilasha R ◽  
Kavitha S

Enormous successes have been obtained against the control of major epidemic diseases, such as SARS, MERS, Ebola, Swine Flu in the past. Dynamic interplay of biological, socio-cultural and ecological factors, together with novel aspects of human-animal interphase, pose additional challenges with respect to the emergence of infectious diseases. The important challenges faced in the control and prevention of emerging and re-emerging infectious diseases range from understanding the impact of factors that are necessary for the emergence, to development of strengthened surveillance systems that can mitigate human suffering and death. The aim of the current study is to assess the awareness of symptomatic differences between viral diseases like COVID-19, SARS, Swine flu and common cold among dental students that support the prevention of emergence or re-emergence. Cross-sectional type of study conducted among the undergraduate students comprising 100 Subjects. A questionnaire comprising 15 questions in total were framed, and responses were collected in Google forms in SPSS Software statistical analysis. The study has concluded that dental students have an awareness of the symptomatic differences between infectious viral disease. The study concluded that the awareness of symptomatic differences between viral diseases like COVID-19, SARS, Swine flu, Common cold is good among the dental students who would pave the way for early diagnosis and avoid spreading of such diseases. A further awareness can be created by regular webinars, seminars and brainstorming sessions among these healthcare professionals.


2020 ◽  
Vol 20 (3) ◽  
pp. 284-290
Author(s):  
Jocelyn Chan ◽  
Yue Wu ◽  
James Wood ◽  
Mohammad Muhit ◽  
Mohammed K. Mahmood ◽  
...  

Background and Objectives: Congenital Rubella Syndrome (CRS) is the leading cause of vaccine-preventable congenital anomalies. Comprehensive country-level data on the burden of CRS in low and middle-income countries, such as Bangladesh, are scarce. This information is essential for assessing the impact of rubella vaccination programs. We aim to systematically review the literature on the epidemiology of CRS and estimate the burden of CRS in Bangladesh. Methods: We conducted a systematic review of existing literature and transmission modelling of seroprevalence studies to estimate the pre-vaccine period burden of CRS in Bangladesh. OVID Medline (1948 – 23 November 2016) and OVID EMBASE (1974 – 23 November 2016) were searched using a combination of the database-specific controlled vocabulary and free text terms. We used an age-stratified deterministic model to estimate the pre-vaccination burden of CRS in Bangladesh. Findings: Ten articles were identified, published between 2000 and 2014, including seven crosssectional studies, two case series and one analytical case-control study. Rubella seropositivity ranged from 47.0% to 86.0% among all age population. Rubella sero–positivity increased with age. Rubella seropositivity among women of childbearing age was 81.0% overall. The estimated incidence of CRS was 0·99 per 1,000 live births, which corresponds to approximately 3,292 CRS cases annually in Bangladesh. Conclusion: The estimated burden of CRS in Bangladesh during the pre-vaccination period was high. This will provide important baseline information to assess the impact and cost-effectiveness of routine rubella immunisation, introduced in 2012 in Bangladesh.


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