Resurgent rotavirus diarrhoea outbreak five years after introduction of rotavirus vaccine in Botswana, 2018

INTRODUCTION

Botswana had a resurgent diarrhea outbreak in 2018, mainly affecting children under five years old. Botswana introduced rotavirus vaccine (RotarixTM) into the national immunization programme in July 2012. Official rotavirus vaccine coverage estimates averaged 77.2% over the five years following introduction.

MATERIALS AND METHODS

The outbreak was investigated using multiple data sources, including stool laboratory testing, immunization data review, water assessment, and vaccine storage assessment. We reviewed official reports of the routine immunization data from 2013 to 2017 and compared district-level rotavirus vaccine coverage with district-level attack rates during the outbreak.

RESULTS

During the outbreak, a total of 228 stool samples were tested at the national health laboratory and 152 (67%) of the specimens were positive for rotavirus. A portion of adequate samples (80) were selected for referral to the Regional Reference Lab. The laboratory testing of 80 samples at the Regional Reference Laboratory in South Africa showed that 91% of the stool samples were positive for rotavirus, and the dominant strain 47/80 (58.7%) was G3P[8]. The immunization data showed that rotavirus vaccine coverage varied widely among districts, and there was no correlation between districts with high attack rates and those with low immunization coverage. Water assessment showed that some water sources were contaminated with E Coli. There was no problem with vaccine storage.

CONCLUSION

The outbreak was caused by rotavirus G3P[8], a strain that was not common in the country prior to the outbreak. Despite the significant pressure and anxiety that outbreaks cause, the number of diarrhea cases and deaths were less compared to pre-vaccine era due to the impact of vaccination. This highlights the need for continuous implementation of high impact child survival interventions.

Progress Toward Measles Elimination - African Region, 2017-2021

Worldwide, measles remains a major cause of disease and death; the highest incidence is in the World Health Organization African Region (AFR). In 2011, the 46 AFR member states established a goal of regional measles elimination by 2020; this report describes progress during 2017-2021. Regional coverage with a first dose of measles-containing vaccine (MCV) decreased from 70% in 2017 to 68% in 2021, and the number of countries with ≥95% coverage decreased from six (13%) to two (4%). The number of countries providing a second MCV dose increased from 27 (57%) to 38 (81%), and second-dose coverage increased from 25% to 41%. Approximately 341 million persons were vaccinated in supplementary immunization activities, and an estimated 4.5 million deaths were averted by vaccination. However, the number of countries meeting measles surveillance performance indicators declined from 26 (62%) to nine (22%). Measles incidence increased from 69.2 per 1 million population in 2017 to 81.9 in 2021. The number of estimated annual measles cases and deaths increased 22% and 8%, respectively. By December 2021, no country in AFR had received verification of measles elimination. To achieve a renewed regional goal of measles elimination in at least 80% of countries by 2030, intensified efforts are needed to recover and surpass levels of surveillance performance and coverage with 2 MCV doses achieved before the COVID-19 pandemic.

Accelerating measles and rubella elimination through research and innovation - Findings from the Measles & Rubella Initiative research prioritization process, 2016

The Measles & Rubella Initiative (M&RI) identified five key strategies to achieve measles and rubella elimination, including research and innovation to support cost-effective operations and improve vaccination and diagnostic tools. In 2016, the M&RI Research and Innovation Working Group (R&IWG) completed a research prioritization process to identify key research questions and update the global research agenda. The R&IWG reviewed meeting reports and strategic planning documents and solicited programmatic inputs from vaccination experts at the program operational level through a web survey, to identify previous research priorities and new research questions. The R&IWG then convened a meeting of experts to prioritize the identified research questions in four strategic areas: (1) epidemiology and economics, (2) surveillance and laboratory, (3) immunization strategies, and (4) demand creation and communications. The experts identified 19 priority research questions in the four strategic areas to address key areas of work necessary to further progress toward elimination. Future commitments from partners will be needed to develop a platform for improved coordination with adequate and predictable resources for research implementation and innovation to address these identified priorities.

Research priorities for accelerating progress toward measles and rubella elimination identified by a cross-sectional web-based survey

BACKGROUND

In 2012, the World Health Assembly endorsed the Global Vaccine Action Plan (GVAP) that set a target to eliminate measles and rubella in five of the six World Health Organization (WHO) regions by 2020. Significant progress has been made toward achieving this goal through intensive efforts by countries and Measles & Rubella Initiative (M&RI) partners. Accelerating progress will require evidence-based approaches to improve implementation of the core strategies in the Global Measles and Rubella Strategic Plan. The M&RI Research and Innovation Working Group (R&IWG) conducted a web-based survey as part of a process to identify measles and rubella research priorities. Survey findings were used to inform discussions during a meeting of experts convened by the M&RI at the Pan American Health Organization in November 2016.

METHODS

The cross-sectional web-based survey of scientific and programmatic experts included questions in four main topic areas: (1) epidemiology and economics (epidemiology); (2) new tools for surveillance, vaccine delivery, and laboratory testing (new tools); (3) immunization strategies and outbreak response (strategies); and (4) vaccine demand and communications (demand). Analyses were stratified by the six WHO regions and by global, regional, or national/sub-national level of respondents.

RESULTS

The six highest priority research questions selected by survey respondents from the four topic areas were the following: (1) What are the causes of outbreaks in settings with high reported vaccination coverage? (epidemiology); (2) Can affordable diagnostic tests be developed to confirm measles and rubella cases rapidly and accurately at the point of care? (new tools); (3) What are effective strategies for increasing coverage of the routine first dose of measles vaccine administered at 9 or 12 months? (strategies); (4) What are effective strategies for increasing coverage of the second dose given after the first year of life? (strategies); (5) How can communities best be engaged in planning, implementing and monitoring health services including vaccinations? (demand); (6) What capacity building is needed for health workers to be able to identify and work more effectively with community leaders? (demand). Research priorities varied by region and by global/regional/national levels for all topic areas.

CONCLUSIONS

Research and innovation will be critical to make further progress toward achieving the GVAP measles and rubella elimination goals. The results of this survey can be used to inform decision-making for investments in research activities at the global, regional, and national levels.

The Impact of Recent Rubella Vaccine Introduction in 5 Countries in The African Region

The World Health Organization (WHO) recommends that countries introduce rubella containing vaccines (RCVs) to reduce rubella circulation and the occurrence of congenital rubella syndrome (CRS). As of June 2017, a total of 18 countries have already introduced or are in the process of introducing RCV in routine child vaccination programs. RCV introduction during 2013 - 2014 in five countries in the Region resulted in a reduction of rubella incidence of 48% to 96% in the post-introduction period as compared to the average incidence in the years before introduction. These results suggest that initial mass vaccination campaigns and introduction of RCVs in routine immunization programs result in significant reduction in rubella incidence and a reduced potential for the occurrence of CRS.

Introduction of the Second Dose of Measles Containing Vaccine in the Childhood Vaccination Programs Within the WHO Africa Region - Lessons Learnt

BACKGROUND

WHO recommends all countries to include a second routine dose of measles containing vaccine (MCV2) in their national routine vaccination schedules regardless of the level of coverage with the first routine dose of measles containing vaccine (MCV1). As of Dec 2016, 26 countries in the African Region have introduced MCV2.

METHODS

We reviewed the WHO UNICEF coverage estimates for MCV1 and MCV2 in these countries, and the reports of the post introduction evaluation of MCV2 from 11 countries.

RESULTS

Twenty three countries have WHO/UNICEF estimates of MCV2 coverage available in 2015. Of these, 2 countries have coverage of ≥ 95% for both MCV1 and MCV2 while 5 countries have coverage of > 80% for both doses. Dropout rates of >20% MCV1 - MCV2 exist in 12 countries. Post-MCV2 introduction evaluations done in 11 countries from 2012 to 2015 showed that inadequate health worker training, insufficient sensitization and awareness generation among parents and suboptimal dose recording practices were common programmatic weaknesses that contributed to the low MCV2 coverage in these countries.

CONCLUSION

MCV2 coverage remains low as reflected in large drop-out rates in most countries. Higher MCV2 coverage is necessary to sustainably achieve the regional measles elimination goal. National immunization programs must improve implementation of MCV2 using the standard introduction and evaluation guidelines available for EPI program planning.

Development of a District-Level Programmatic Assessment Tool for Risk of Measles Virus Transmission

All six World Health Organization (WHO) regions have now set goals for measles elimination by or before 2020. To prioritize measles elimination efforts and use available resources efficiently, there is a need to identify at-risk areas that are offtrack from meeting performance targets and require strengthening of programmatic efforts. This article describes the development of a WHO measles programmatic risk assessment tool to be used for monitoring, guiding, and sustaining measles elimination efforts at the subnational level. We outline the tool development process; the tool specifications and requirements for data inputs; the framework of risk categories, indicators, and scoring; and the risk category assignment. Overall risk was assessed as a function of indicator scores that fall into four main categories: population immunity, surveillance quality, program performance, and threat assessment. On the basis of the overall score, the tool assigns each district a risk of either low, medium, high, or very high. The cut-off criteria for the risk assignment categories were based on the distribution of scores from all possible combinations of individual indicator cutoffs. The results may be used for advocacy to communicate risk to policymakers, mobilize resources for corrective actions, manage population immunity, and prioritize programmatic activities. Ongoing evaluation of indicators will be needed to evaluate programmatic performance and plan risk mitigation activities effectively. The availability of a comprehensive tool that can identify at-risk districts will enhance efforts to prioritize resources and implement strategies for achieving the Global Vaccine Action Plan goals for measles elimination.

Development of the World Health Organization Measles Programmatic Risk Assessment Tool Using Experience from the 2009 Measles Outbreak in Namibia

In the World Health Organization (WHO) African region, reported measles cases decreased by 80% and measles mortality declined by 88% during 2000-2012. Based on current performance trends, however, focused efforts will be needed to achieve the regional measles elimination goal. To prioritize efforts to strengthen implementation of elimination strategies, the Centers for Disease Control and Prevention and WHO developed a measles programmatic risk assessment tool to identify high-risk districts and guide and strengthen program activities at the subnational level. This article provides a description of pilot testing of the tool in Namibia using comparisons of high-risk districts identified using 2006-2008 data with reported measles cases and incidence during the 2009 outbreak. Of the 34 health districts in Namibia, 11 (32%) were classified as high risk or very high risk, including the district of Engela where the outbreak began in 2009. The district of Windhoek, including the capital city of Windhoek, had the highest overall risk score-driven primarily by poor population immunity and immunization program performance-and one of the highest incidences during the outbreak. Other high-risk districts were either around the capital district or in the northern part of the country near the border with Angola. Districts categorized as high or very high risk based on the 2006-2008 data generally experienced high measles incidence during the large outbreak in 2009, as did several medium- or low-risk districts. The tool can be used to guide measles elimination strategies and to identify programmatic areas that require strengthening.

Progress Toward Measles Elimination - African Region, 2013-2016

In 2011, the 46 World Health Organization (WHO) African Region (AFR) member states established a goal of measles elimination* by 2020, by achieving 1) ≥95% coverage of their target populations with the first dose of measles-containing vaccine (MCV1) at national and district levels; 2) ≥95% coverage with measles-containing vaccine (MCV) per district during supplemental immunization activities (SIAs); and 3) confirmed measles incidence of <1 case per 1 million population in all countries (1). Two key surveillance performance indicator targets include 1) investigating ≥2 cases of nonmeasles febrile rash illness per 100,000 population annually, and 2) obtaining a blood specimen from ≥1 suspected measles case in ≥80% of districts annually (2). This report updates the previous report (3) and describes progress toward measles elimination in AFR during 2013-2016. Estimated regional MCV1 coverage† increased from 71% in 2013 to 74% in 2015.§ Seven (15%) countries achieved ≥95% MCV1 coverage in 2015.¶ The number of countries providing a routine second MCV dose (MCV2) increased from 11 (24%) in 2013 to 23 (49%) in 2015. Forty-one (79%) of 52 SIAs** during 2013-2016 reported ≥95% coverage. Both surveillance targets were met in 19 (40%) countries in 2016. Confirmed measles incidence in AFR decreased from 76.3 per 1 million population to 27.9 during 2013-2016. To eliminate measles by 2020, AFR countries and partners need to 1) achieve ≥95% 2-dose MCV coverage through improved immunization services, including second dose (MCV2) introduction; 2) improve SIA quality by preparing 12-15 months in advance, and using readiness, intra-SIA, and post-SIA assessment tools; 3) fully implement elimination-standard surveillance††; 4) conduct annual district-level risk assessments; and 5) establish national committees and a regional commission for the verification of measles elimination.

Application of the World Health Organization Programmatic Assessment Tool for Risk of Measles Virus Transmission-Lessons Learned from a Measles Outbreak in Senegal

The World Health Organization (WHO) African Region set a goal for regional measles elimination by 2020; however, regional measles incidence was 125/1,000,000 in 2012. To support elimination efforts, the WHO and U.S. Centers for Disease Control and Prevention developed a tool to assess performance of measles control activities and identify high-risk areas at the subnational level. The tool uses routinely collected data to generate district-level risk scores across four categories: population immunity, surveillance quality, program performance, and threat assessment. To pilot test this tool, we used retrospective data from 2006 to 2008 to identify high-risk districts in Senegal; results were compared with measles case-based surveillance data from 2009 when Senegal experienced a large measles outbreak. Seventeen (25%) of 69 districts in Senegal were classified as high or very high risk. The tool highlighted how each of the four categories contributed to the total risk scores for high or very high risk districts. Measles case-based surveillance reported 986 cases during 2009, including 368 laboratory-confirmed, 540 epidemiologically linked, and 78 clinically compatible cases. The seven districts with the highest numbers of laboratory-confirmed or epidemiologically linked cases were within the capital region of Dakar. All except one of these seven districts were estimated to be high or very high risk, suggesting that districts identified as high risk by the tool have the potential for measles outbreaks. Prospective use of this tool is recommended to help immunization and surveillance program managers identify high-risk areas in which to strengthen specific programmatic weaknesses and mitigate risk for potential measles outbreaks.

Surveys of measles vaccination coverage in eastern and southern Africa: a review of quality and methods used

Objective

To assess the methods used in the evaluation of measles vaccination coverage, identify quality concerns and provide recommendations for improvement.

Methods

We reviewed surveys that were conducted to evaluate supplementary measles immunization activities in eastern and southern Africa during 2012 and 2013. We investigated the organization(s) undertaking each survey, survey design, sample size, the numbers of study clusters and children per study cluster, recording of immunizations and methods of analysis. We documented sampling methods at the level of clusters, households and individual children. We also assessed the length of training for field teams at national and regional levels, the composition of teams and the supervision provided.

Findings

The surveys were conducted in Comoros, Eritrea, Ethiopia, Kenya, Lesotho, Malawi, Mozambique, Namibia, Rwanda, Swaziland, Uganda, Zambia and Zimbabwe. Of the 13 reports we reviewed, there were weaknesses in 10 of them for ethical clearance, 9 for sample size calculation, 6 for sampling methods, 12 for training structures, 13 for supervision structures and 11 for data analysis.

Conclusion

We recommend improvements in the documentation of routine and supplementary immunization, via home-based vaccination cards or other records. For surveys conducted after supplementary immunization, a standard protocol is required. Finally, we recommend that standards be developed for report templates and for the technical review of protocols and reports. This would ensure that the results of vaccination coverage surveys are accurate, comparable, reliable and valuable for programme improvement.

Evaluation of economic costs of a measles outbreak and outbreak response activities in Keffa Zone, Ethiopia

OBJECTIVE

To estimate the economic impact of a measles outbreak and response activities that occurred in Keffa Zone, Ethiopia with 5257 reported cases during October 1, 2011-April 8, 2012, using the health sector and household perspectives.

METHODS

We collected cost input data through interviews and record reviews with government and partner agency staff and through a survey of 100 measles cases-patients and their caretakers. We used cost input data to estimate the financial and opportunity costs of the following outbreak and response activities: investigation, treatment, case management, active surveillance, immunization campaigns, and immunization system strengthening.

FINDINGS

The economic cost of the outbreak and response was 758,869 United States dollars (US$), including the opportunity cost of US$327,545 (US$62.31/case) and financial cost of US$431,324 (US$82.05/case). Health sector costs, including the immunization campaign (US$72.29/case), accounted for 80% of the economic cost. Household economic cost was US$29.18/case, equal to 6% of the household median annual income. 92% of financial costs were covered by partner agencies.

CONCLUSION

The economic cost of the measles outbreak was substantial when compared to household income and health sector expenditures. Improvement in two-dose measles vaccination coverage above 95% would both reduce measles incidence and save considerable outbreak-associated costs to both the health sector and households.

Progress toward measles preelimination--African Region, 2011-2012

In 2008, the 46 member states of the World Health Organization (WHO) African Region (AFR) adopted a measles preelimination goal to reach by the end of 2012 with the following targets: 1) >98% reduction in estimated regional measles mortality compared with 2000, 2) annual measles incidence of fewer than five reported cases per million population nationally, 3) >90% national first dose of measles-containing vaccine (MCV1) coverage and >80% MCV1 coverage in all districts, and 4) >95% MCV coverage in all districts by supplementary immunization activities (SIAs). Surveillance performance objectives were to report two or more cases of nonmeasles febrile rash illness per 100,000 population, one or more suspected measles cases investigated with blood specimens in ≥80% of districts, and 100% completeness of surveillance reporting from all districts. This report updates previous reports and describes progress toward the measles preelimination goal during 2011-2012. In 2012, 13 (28%) member states had >90% MCV1 coverage, and three (7%) reported >90% MCV1 coverage nationally and >80% coverage in all districts. During 2011-2012, four (15%) of 27 SIAs with available information met the target of >95% coverage in all districts. In 2012, 16 of 43 (37%) member states met the incidence target of fewer than five cases per million, and 19 of 43 (44%) met both surveillance performance targets. In 2011, the WHO Regional Committee for AFR established a goal to achieve measles elimination by 2020. To achieve this goal, intensified efforts to identify and close population immunity gaps and improve surveillance quality are needed, as well as committed leadership and ownership of the measles elimination activities and mobilization of adequate resources to complement funding from global partners.

Measles resurgence in southern Africa: challenges to measles elimination

INTRODUCTION

In seven southern African countries (Botswana, Lesotho, Malawi, Namibia, South Africa, Swaziland and Zimbabwe), following implementation of a measles mortality reduction strategy starting in 1996, the number of annually reported measles cases decreased sharply to less than one per million population during 2006-2008. However, during 2009-2010, large outbreaks occurred in these countries. In 2011, a goal for measles elimination by 2020 was set in the World Health Organization (WHO) African Region (AFR). We reviewed the implementation of the measles control strategy and measles epidemiology during the resurgence in the seven southern African countries.

METHODS

Estimated coverage with routine measles vaccination, supplemental immunization activities (SIA), annually reported measles cases by country, and measles surveillance and laboratory data were analyzed using descriptive analysis.

RESULTS

In the seven countries, coverage with the routine first dose of measles-containing vaccine (MCV1) decreased from 80% to 65% during 1996-2004, then increased to 84% in 2011; during 1996-2011, 79,696,523 people were reached with measles vaccination during 45 SIAs. Annually reported measles cases decreased from 61,160 cases to 60 cases and measles incidence decreased to <1 case per million during 1996-2008. During 2009-2010, large outbreaks that included cases among older children and adults were reported in all seven countries, starting in South Africa and Namibia in mid-2009 and in the other five countries by early 2010. The measles virus genotype detected was predominantly genotype B3.

CONCLUSION

The measles resurgence highlighted challenges to achieving measles elimination in AFR by 2020. To achieve this goal, high two-dose measles vaccine coverage by strengthening routine immunization systems and conducting timely SIAs targeting expanded age groups, potentially including young adults, and maintaining outbreak preparedness to rapidly respond to outbreaks will be needed.

Measles mortality reduction and pre-elimination in the African region, 2001-2009

INTRODUCTION

In 2001, countries in the African region adopted the measles-associated mortality reduction strategy recommended by the World Health Organization and the United Nations Children's Fund. With support from partners, these strategies were implemented during 2001-2009.

METHODS

To assess implementation, estimates of the first dose of measles vaccination through routine services (MCVI) and reported coverage for measles supplemental immunization activities (SIAs) were reviewed. Measles surveillance data were analyzed.

RESULTS

During 2001-2009, regional MCV1 coverage increased from 56% to 69%, and >425 million children received measles vaccination through 125 SIAs. Measles case-based surveillance was established in 40 of 46 countries; the remaining 6 have aggregated case reporting. From 2001 through 2008, reported measles cases decreased by 92%, from 492,116 to 37,010; however, in 2009, cases increased to 83,625.

CONCLUSIONS

The implementation of the recommended strategies led to a marked decrease in measles cases in the region; however, the outbreaks occurring since 2008 indicate suboptimal vaccination coverage. To achieve high MCV1 coverage, provide a second dose through either periodic SIAs or routine services, and to ensure further progress toward attaining the regional measles pre-elimination goal by 2012, a renewed commitment from implementing partners and donors is needed.