Sero-prevalence of yellow fever and related Flavi viruses in Ethiopia: a public health perspective.

BACKGROUND: Yellow fever (YF) is a viral hemorrhagic fever, endemic in the tropical forests of Africa and Central and South America. The disease is transmitted by mosquitoes infected with the yellow fever virus (YFV). Ethiopia was affected by the largest YF outbreak since the vaccination era during 1960-1962. The recent YF outbreak occurred in 2013 in Southern part of the country. The current survey of was carried out to determine the YF seroprevalence so as to make recommendations from YF prevention and control in Ethiopia. METHODOLOGY: A multistage cluster design was utilized. Consequently, the country was divided into 5 ecological zones and two sampling towns were picked per zone randomly. A total of 1643 serum samples were collected from human participants. The serum samples were tested for IgG antibody against YFV using ELISA. Any serum sample testing positive by ELISA was confirmed by plaque reduction neutralization test (PRNT). In addition, differential testing was performed for other flaviviruses, namely dengue, Zika and West Nile viruses. RESULT: Of the total samples tested, 10 (0.61%) were confirmed to be IgG positive against YFV and confirmed with PRNT. Nine (0.5%) samples were antibody positive for dengue virus, 15(0.9%) forWest Nile virus and 7 (0.4%) for Zika virus by PRNT. Three out of the five ecological zones namely zones 1, 3 and 5 showed low levels (< 2%) of IgG positivity against YFV. A total of 41(2.5%) cases were confirmed to be positive for one of flaviviruses tested. CONCLUSION: Based on the seroprevalence data, the level of YFV activity and the risk of a YF epidemic in Ethiopia are low. However additional factors that could impact the likelihood of such an epidemic occurring should be considered before making final recommendations for YF prevention and control in Ethiopia. Based on the results of the serosurvey and other YF epidemic risk factors considered, a preventive mass vaccination campaign is not recommended, however the introduction of YF vaccine in routine EPI is proposed nationwide, along with strong laboratory based YF surveillance.

Delivery of Multiple Child and Maternal Health Interventions during Supplementary Immunization Campaign in Rwanda, 2013: Lessons Learnt.

OBJECTIVE: This paper assesses and describes the estimated coverage of the Measles Rubella (MR) campaign in each district; the national estimate of coverage for Human Papilloma Virus (HPV) vaccination campaign and Vitamin A supplementation simultaneously implemented in 2013. METHODS: We applied descriptive statistics and epidemiological tools to the outcomes of the campaigns to assess the coverage achieved on the different child and maternal health interventions. We also assessed the Adverse Events following Immunization (AEFI) where the evaluation was used at the same time to assess the routine immunization performance coverage for children 12-24 months for all childhood antigens, Tetanus Toxoid coverage among mothers of infants, combined with routine immunization performance evaluation, skilled delivery and bed nets use in Rwanda. RESULTS: Results indicated that among the eligible targets, 97.5% received MR vaccine, 91% received HPV doses, and 83% got Vitamin A. The integrated vaccination of MR with HPV did not result in any serious AEFI. Coverage for antigens and doses given early in life was above 95% with card retention of 80%. BCG to measles dropout by card was 8.5%. Main reasons for non-vaccination indicated need for more specific immunization education. About 96.8% of mothers delivered in health institutions and 95% of the mothers slept under bed nets the night before the survey. CONCLUSION: Rwanda successfully implemented an integrated coverage evaluation survey of the integrated vaccination campaign and routine immunization with statistically valid estimates. We drew lessons that information on routine immunization can be collected during post campaign survey evaluations. The district estimates should guide the programme performance improvement.

How to Increase Vaccination Acceptance Among Apostolic Communities: Quantitative Results from an Assessment in Three Provinces in Zimbabwe.

A worldwide increasing trend toward vaccine hesitancy has been reported. Measles outbreaks in southern Africa in 2009-2010 were linked to objections originating from Apostolic gatherings. Founded in Zimbabwe in the 1950s, the Apostolic church has built up a large number of followers with an estimated 3.5 million in Zimbabwe in 2014. To inform planning of interventions for the 2015 measles-rubella vaccination campaign, we assessed vaccination status and knowledge, attitudes and practices among purposive samples of Apostolic caregivers in three districts each in Harare City, Manicaland and Matabeleland South in Zimbabwe. We conducted structured interviews among 97 caregivers of children aged 9-59 months and collected vaccination status for 126 children. Main Apostolic affiliations were Johanne Marange (53%), Madida (13%) and Gospel of God (11%) with considerable variation across assessment areas. The assessment also showed considerable variation among Apostolic communities in children ever vaccinated (14-100%) and retention of immunization cards (0-83%) of ever vaccinated. Overall retention of immunization cards (12%) and documented vaccination status by card (fully vaccinated = 6%) were low compared to previously reported measures in the general population. Mothers living in monogamous relationships reported over 90% of all DTP-HepB-Hib-3, measles and up to date immunizations during the first life year documented by immunization card. Results revealed opportunities to educate about immunization during utilization of health services other than vaccinations, desire to receive information about vaccinations from health personnel, and willingness to accept vaccinations when offered outside of regular services. Based on the results of the assessment, specific targeted interventions were implemented during the vaccination campaign, including an increased number of advocacy activities by district authorities. Also, health workers offered ways and timing to vaccinate children that catered to the specific situation of Apostolic caregivers, including flexible service provision after hours and outside of health facilities, meeting locations chosen by caregivers, using mobile phones to set up meeting locations, and documentation of vaccination in health facilities if home-based records posed a risk for caregivers. Coverage survey results indicate that considerable progress has been made since 2010 to increase vaccination acceptability among Apostolic communities in Zimbabwe. Further efforts will be needed to vaccinate all Apostolic children during routine and campaign activities in the country, and the results from our assessment can contribute toward this goal.

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.

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.

Trends in differences between births and surviving infants reported for immunization program planning and external data sources in Eastern and Southern Africa 2000-2013.

To inform our WHO team's support for immunization programs in Member States in Eastern and Southern Africa, we compared annual trends from 2000 to 2013 in target populations reported by Member States through the WHO-UNICEF joint reporting form with United Nations (UN) population projections and modeled infant mortality estimates from the UN Inter-agency Group for Child Mortality Estimation. Our findings indicated a tendency of underestimating births and surviving infants used by Member States as denominators for administrative immunization coverage rates, resulting in or contributing to overestimation of coverage. The difference with UN estimates appeared to be more pronounced for surviving infants than births. Measures of central tendency for individual country differences indicated that those differences decreased over time. Comparing trends of births and surviving infants with external sources can help monitoring progress in efforts to provide accurate and reliable target population estimates and sampling frames.

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.

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.