Measles and rubella elimination: protecting children through immunization in South-East Asia Region (SEAR).

The South-East Asia Region (SEAR) adopted the goal of "measles and rubella elimination by 2023". The goal was revised in 2019 to 'measles and rubella elimination by 2023' The strategies adopted to reach the goal included achieving ≥95% coverage with 2 doses of measles- and rubella-containing vaccine (MCV2; RCV2); establishing effective case-based surveillance supported by an accredited laboratory network; and implementing rapid response measures to control measles outbreaks. Of the 11 countries in the Region, to date five countries have eliminated measles and rubella and two more have controlled rubella. An estimated 242 million cases and 4.7 million deaths due to measles were averted between 2014 and 2022. The high-level political commitment, programmatic infrastructure and partnerships developed for the elimination of polio and maternal and neonatal tetanus played a critical role in this achievement. WHO, supported by key partners, provided technical support and strategic guidance for programmatic improvements, generated evidence to guide policy and strategic shifts, strengthened capacity of health workforce and conducted periodic programmatic reviews. However, unexpected occurrence of COVID-19 pandemic impacted vaccine coverage and quality of surveillance, thereby delaying achievement of the goal, and necessitating a revision of the target date of elimination.

Progress Toward Measles and Rubella Elimination - Indonesia, 2013-2022.

In 2019, Indonesia and the other countries in the World Health Organization South-East Asia Region adopted the goal of measles and rubella elimination by 2023. This report describes Indonesia's progress toward measles and rubella elimination during 2013-2022. During this period, coverage with a first dose of measles-containing vaccine (MCV) decreased from 87% to 84%, and coverage with a second MCV dose decreased from 76% to 67%. After rubella vaccine was introduced in 2017, coverage with the first dose of rubella-containing vaccine increased approximately fivefold, from 15% in 2017 to 84% in 2022. During 2013-2021, annual reported measles incidence decreased by 95%, from 33.2 to 1.4 cases per million population; reported rubella incidence decreased 89%, from 9.3 to 1.0 cases per million population. However, a large surge in measles and rubella cases occurred in 2022, with a reported measles incidence of 29 cases per million and a reported rubella incidence of 3 per million, primarily related to disruption in immunization services caused by the COVID-19 pandemic. In 2022, approximately 26 million children (an estimated 73% of the target population) received a combined measles- and rubella-containing vaccine during supplementary immunization activities completed in 32 provinces. Progress toward measles and rubella elimination in Indonesia has been made; however, continued and urgent efforts are needed to restore routine immunization services that were adversely affected by the COVID-19 pandemic and close immunity gaps to accelerate progress toward measles and rubella elimination.

Population structure and antimicrobial resistance patterns of Salmonella Typhi and Paratyphi A amid a phased municipal vaccination campaign in Navi Mumbai, India.

We performed whole-genome sequencing of 174 Salmonella Typhi and 54 Salmonella Paratyphi A isolates collected through prospective surveillance in the context of a phased typhoid conjugate vaccine introduction in Navi Mumbai, India. We investigate the temporal and geographical patterns of emergence and spread of antimicrobial resistance. We evaluated the relationship between the spatial distance between households and genetic clustering of isolates. Most isolates were non-susceptible to fluoroquinolones, with nearly 20% containing ≥3 quinolone resistance-determining region mutations. Two H58 isolates carried an IncX3 plasmid containing blaSHV-12, associated with ceftriaxone resistance, suggesting that the ceftriaxone-resistant isolates from India independently evolved on multiple occasions. Among S. Typhi, we identified two main clades circulating (2.2 and 4.3.1 [H58]); 2.2 isolates were closely related following a single introduction around 2007, whereas H58 isolates had been introduced multiple times to the city. Increasing geographic distance between isolates was strongly associated with genetic clustering (odds ratio [OR] = 0.72 per km; 95% credible interval [CrI]: 0.66-0.79). This effect was seen for distances up to 5 km (OR = 0.65 per km; 95% CrI: 0.59-0.73) but not seen for distances beyond 5 km (OR = 1.02 per km; 95% CrI: 0.83-1.26). There was a non-significant reduction in odds of clustering for pairs of isolates in vaccination communities compared with non-vaccination communities or mixed pairs compared with non-vaccination communities. Our findings indicate that S. Typhi was repeatedly introduced into Navi Mumbai and then spread locally, with strong evidence of spatial genetic clustering. In addition to vaccination, local interventions to improve water and sanitation will be critical to interrupt transmission. IMPORTANCE Enteric fever remains a major public health concern in many low- and middle-income countries, as antimicrobial resistance (AMR) continues to emerge. Geographical patterns of typhoidal Salmonella spread, critical to monitoring AMR and planning interventions, are poorly understood. We performed whole-genome sequencing of S. Typhi and S. Paratyphi A isolates collected in Navi Mumbai, India before and after a typhoid conjugate vaccine introduction. From timed phylogenies, we found two dominant circulating lineages of S. Typhi in Navi Mumbai-lineage 2.2, which expanded following a single introduction a decade prior, and 4.3.1 (H58), which had been introduced repeatedly from other parts of India, frequently containing "triple mutations" conferring high-level ciprofloxacin resistance. Using Bayesian hierarchical statistical models, we found that spatial distance between cases was strongly associated with genetic clustering at a fine scale (<5 km). Together, these findings suggest that antimicrobial-resistant S. Typhi frequently flows between cities and then spreads highly locally, which may inform surveillance and prevention strategies.

Progress Toward Rubella Elimination - World Health Organization South-East Asia Region, 2013-2021.

During 2013, the 11 countries of the World Health Organization (WHO) South-East Asia Region* (SEAR) adopted the goals of measles elimination and rubella and congenital rubella syndrome (CRS) control† by 2020. During 2019, SEAR countries declared a broader goal for eliminating both measles and rubella§ by 2023 (1). Before 2013, only five SEAR countries had introduced rubella-containing vaccine (RCV). This report updates a previous report and describes progress toward rubella elimination in SEAR during 2013-2021 (2). During 2013-2021, six SEAR countries introduced RCV; all countries in the Region now use RCV in routine immunization. Routine immunization coverage with the first dose of a rubella-containing vaccine (RCV1) increased >600%, from 12% during 2013 to 86% during 2021, and an estimated 515 million persons were vaccinated via RCV supplementary immunization activities (SIAs)¶ during 2013-2021. During this time, annual reported rubella incidence declined by 80%, from 5.5 to 1.1 cases per million population. Maldives and Sri Lanka are verified as having achieved rubella elimination; Bhutan, North Korea, and Timor-Leste have halted endemic transmission of rubella virus for >36 months. SEAR has made substantial progress toward rubella elimination; however, intensified measures are needed to achieve elimination.

Delivery cost of the first public sector introduction of typhoid conjugate vaccine in Navi Mumbai, India.

Navi Mumbai Municipal Corporation (NMMC), a local government in Mumbai, India, implemented the first public sector TCV campaign in 2018. This study estimated the delivery costs of this TCV campaign using a Microsoft Excel-based tool based on a micro-costing approach from the government (NMMC) perspective. The campaign's financial (direct expenditures) and economic costs (financial costs plus the monetized value of additional donated or existing items) incremental to the existing immunization program were collected. The data collection methods involved consultations with NMMC staff, reviews of financial and programmatic records of NMMC and the World Health Organization (WHO), and interviews with the health staff of sampled urban health posts (UHPs). Three UHPs were purposively sampled, representing the three dominant residence types in the catchment area: high-rise, slum, and mixed (high-rise and slum) areas. The high-rise area UHP had lower vaccination coverage (47%) compared with the mixed area (71%) and slum area UHPs (76%). The financial cost of vaccine and vaccination supplies (syringes, safety boxes) was $1.87 per dose, and the economic cost was $2.96 per dose in 2018 US dollars. Excluding the vaccine and vaccination supplies cost, the financial delivery cost across the 3 UHPs ranged from $0.37 to $0.53 per dose, and the economic delivery cost ranged from $1.37 to $3.98 per dose, with the highest delivery costs per dose in the high-rise areas. Across all 11 UHPs included in the campaign, the weighted average financial delivery cost was $0.38 per dose, and the economic delivery cost was $1.49 per dose. WHO has recommended the programmatic use of TCV in typhoid-endemic countries, and Gavi has included TCV in its vaccine portfolio. This first costing study of large-scale TCV introduction within a public sector immunization program provides empirical evidence for policymakers, stakeholders, and future vaccine campaign planning.

Programmatic Effectiveness of a Pediatric Typhoid Conjugate Vaccine Campaign in Navi Mumbai, India.

BACKGROUND: The World Health Organization recommends vaccines for prevention and control of typhoid fever, especially where antimicrobial-resistant typhoid circulates. In 2018, the Navi Mumbai Municipal Corporation (NMMC) implemented a typhoid conjugate vaccine (TCV) campaign. The campaign targeted all children aged 9 months through 14 years within NMMC boundaries (approximately 320 000 children) over 2 vaccination phases. The phase 1 campaign occurred from 14 July 2018 through 25 August 2018 (71% coverage, approximately 113 420 children). We evaluated the phase 1 campaign's programmatic effectiveness in reducing typhoid cases at the community level. METHODS: We established prospective, blood culture-based surveillance at 6 hospitals in Navi Mumbai and offered blood cultures to children who presented with fever ≥3 days. We used a cluster-randomized (by administrative boundary) test-negative design to estimate the effectiveness of the vaccination campaign on pediatric typhoid cases. We matched test-positive, culture-confirmed typhoid cases with up to 3 test-negative, culture-negative controls by age and date of blood culture and assessed community vaccine campaign phase as an exposure using conditional logistic regression. RESULTS: Between 1 September 2018 and 31 March 2021, we identified 81 typhoid cases and matched these with 238 controls. Cases were 0.44 times as likely to live in vaccine campaign communities (programmatic effectiveness, 56%; 95% confidence interval [CI], 25% to 74%; P = .002). Cases aged ≥5 years were 0.37 times as likely (95% CI, .19 to .70; P = .002) and cases during the first year of surveillance were 0.30 times as likely (95% CI, .14 to .64; P = .002) to live in vaccine campaign communities. CONCLUSIONS: Our findings support the use of TCV mass vaccination campaigns as effective population-based tools to combat typhoid fever.

Progress Toward Measles and Rubella Elimination - India, 2005-2021.

In 2019, India, along with other countries in the World Health Organization (WHO) South-East Asia Region,* adopted the goal of measles and rubella elimination by 2023,† a revision of the previous goal of measles elimination and control of rubella and congenital rubella syndrome (CRS) by 2020§ (1-3). During 2017-2021, India adopted a national strategic plan for measles and rubella elimination (4), introduced rubella-containing vaccine (RCV) into the routine immunization program, launched a nationwide measles-rubella supplementary immunization activity (SIA) catch-up campaign, transitioned from outbreak-based surveillance to case-based acute fever and rash surveillance, and more than doubled the number of laboratories in the measles-rubella network, from 13 to 27. Strategies included 1) achieving and maintaining high population immunity with at least 95% vaccination coverage by providing 2 doses of measles- and rubella-containing vaccines; 2) ensuring a sensitive and timely case-based measles, rubella and CRS surveillance system; 3) maintaining an accredited measles and rubella laboratory network; 4) ensuring adequate outbreak preparedness and rapid response to measles and rubella outbreaks; and 5) strengthening support and linkages to achieve these strategies, including planning and progress monitoring, advocacy, social mobilization and communication, identification and utilization of synergistic linkages of integrated program efforts, research, and development. This report describes India's progress toward the elimination of measles and rubella during 2005-2021, with a focus on the years 2017-2021.¶ During 2005-2021, coverage with the first dose of a measles-containing vaccine (MCV) administered through routine immunization increased 31%, from 68% to 89%. During 2011-2021, coverage with a second MCV dose (MCV2) increased by 204%, from 27% to 82%. During 2017-2021, coverage with a first dose of RCV (RCV1) increased almost 14-fold, from 6% to 89%. More than 324 million children received a measles- and rubella-containing vaccine (MRCV) during measles-rubella SIAs completed in 34 (94%) of 36 states and union territories (states) during 2017-2019. During 2017-2021, annual measles incidence decreased 62%, from 10.4 to 4.0 cases per 1 million population, and rubella incidence decreased 48%, from 2.3 to 1.2 cases per 1 million population. India has made substantial progress toward measles and rubella elimination; however, urgent and intensified efforts are required to achieve measles and rubella elimination by 2023.

Progress Toward Measles Elimination - South-East Asia Region, 2003-2020.

In 2013, member states of the World Health Organization (WHO) South-East Asia Region* (SEAR) adopted the goal of measles elimination and rubella and congenital rubella syndrome control† by 2020 (1). In 2014, to provide impetus toward achieving this goal, the Regional Director declared measles elimination and rubella control one of the Regional Flagship Priorities. In 2019, SEAR member states declared a revised goal of eliminating both measles and rubella§ by 2023 (2). The recommended strategies to achieve elimination include 1) achieving and maintaining ≥95% coverage with 2 doses of measles- and rubella-containing vaccine in every district through routine or supplementary immunization activities¶ (SIAs); 2) developing and sustaining a sensitive and timely case-based surveillance system that meets recommended performance indicators**; 3) developing and maintaining an accredited laboratory network; 4) achieving timely identification, investigation, and response to measles outbreaks; and 5) collaborating with other public health initiatives to achieve the preceding four strategies. This report updates a previous report and describes progress toward measles elimination in SEAR during 2003-2020 (3). In 2002, coverage with the first dose of a measles-containing vaccine in routine immunization (MCV1) was 70%, and only three countries in SEAR had added a second routine dose of measles-containing vaccine in routine immunization (MCV2). During 2003-2020, all countries introduced MCV2, and estimated coverage with MCV1 increased 35%, from 65% to 88%, and coverage with MCV2 increased 1,233% from 6% to 80%. Approximately 938 million persons were vaccinated in SIAs. Annual reported measles incidence declined by 92%, from 57.0 to 4.8 cases per 1 million population, and estimated deaths decreased by 97%; an estimated 9.3 million deaths were averted by measles vaccination. By 2020, five countries were verified as having achieved measles elimination. To achieve measles elimination in the region by 2023, additional efforts are urgently needed to strengthen routine immunization services and improve measles-containing vaccine (MCV) coverage, conduct periodic high-quality SIAs, and strengthen measles case-based surveillance and laboratory capacity.

Immunogenicity of Fractional Dose Inactivated Poliovirus Vaccine in India.

INTRODUCTION: Following the withdrawal of Sabin type 2 from trivalent oral poliovirus vaccine (tOPV) in 2016, the introduction of ≥1 dose of inactivated poliovirus vaccine (IPV) in routine immunization was recommended, either as 1 full dose (0.5mL, intramuscular) or 2 fractional doses of IPV (fIPV-0.1mL, intradermal). India opted for fIPV. We conducted a comparative assessment of IPV and fIPV. METHODS: This was a 4-arm, open-label, multicenter, randomized controlled trial. Infants were enrolled and vaccines administered according to the study design, and the blood was drawn at age 6, 14, and 18 weeks for neutralization testing against all 3 poliovirus types. RESULTS: Study enrolled 799 infants. The seroconversion against type 2 poliovirus with 2 fIPV doses was 85.8% (95% confidence interval [CI]: 80.1%-90.0%) when administered at age 6 and 14 weeks, 77.0% (95% CI: 70.5-82.5) when given at age 10 and 14 weeks, compared to 67.9% (95% CI: 60.4-74.6) following 1 full-dose IPV at age 14 weeks. CONCLUSION: The study demonstrated the superiority of 2 fIPV doses over 1 full-dose IPV in India. Doses of fIPV given at 6 and 14 weeks were more immunogenic than those given at 10 and 14 weeks. Clinical Trial Registry of India (CTRI). Clinical trial registration number was CTRI/2017/02/007793.

Poliomyelitis seroprevalence in high risk populations of India before the trivalent-bivalent oral poliovirus vaccine switch in 2016.

INTRODUCTION: This study assessed the seroprevalence against all three polioviruses among the last cohort of infants aged 6-11 months who received tOPV before the tOPV-bOPV switch and had an opportunity to receive a full dose of inactivated poliovirus vaccine introduced in the routine immunization schedule. METHODS: Serum was tested for neutralizing antibodies against polioviruses among infants residing in three different risk- category states for poliovirus transmission in India viz., Bihar historically high-risk state for polio, Madhya Pradesh a State with low routine immunization coverage and Chhattisgarh with lower acute flaccid paralysis surveillance indicators. RESULTS: A total of 1113 serum samples were tested across the three states. The overall seroprevalence was 98.5% (97.7-99.2), 98.9% (98.3-99.5) and 94.4% (93.0-95.8) for poliovirus types 1, 2 and 3 respectively. The median antibody titers for corresponding serotypes were 575, 362 and 181. Infants who received five doses of tOPV showed respective seroprevalence rates of 98.7%, 98.7% and 93.7% against types 1, 2 and 3 polioviruses. There was no significant difference in seroprevalence across the group of IPV recipients. The median reciprocal titers across the groups of IPV recipient was significantly higher (p = 0.006) for poliovirus-3. CONCLUSION: The seroprevalence rates observed in the study are historically the highest in the series of serosurveys that India has conducted to assess the population immunity against polioviruses. Poliovirus 2 seroprevalence was very high at the time of the tOPV-bOPV switch in India effected in April 2016.

Decision Making and Implementation of the First Public Sector Introduction of Typhoid Conjugate Vaccine-Navi Mumbai, India, 2018.

BACKGROUND: Typhoid fever prevention and control efforts are critical in an era of rising antimicrobial resistance among typhoid pathogens. India remains one of the highest typhoid disease burden countries, although a highly efficacious typhoid conjugate vaccine (TCV), prequalified by the World Health Organization in 2017, has been available since 2013. In 2018, the Navi Mumbai Municipal Corporation (NMMC) introduced TCV into its immunization program, targeting children aged 9 months to 14 years in 11 of 22 areas (Phase 1 campaign). We describe the decision making, implementation, and delivery costing to inform TCV use in other settings. METHODS: We collected information on the decision making and campaign implementation in addition to administrative coverage from NMMC and partners. We then used a microcosting approach from the local government (NMMC) perspective, using a new Microsoft Excel-based tool to estimate the financial and economic vaccination campaign costs. RESULTS: The planning and implementation of the campaign were led by NMMC with support from multiple partners. A fixed-post campaign was conducted during weekends and public holidays in July-August 2018 which achieved an administrative vaccination coverage of 71% (ranging from 46% in high-income to 92% in low-income areas). Not including vaccine and vaccination supplies, the average financial cost and economic cost per dose of TCV delivery were $0.45 and $1.42, respectively. CONCLUSION: The first public sector TCV campaign was successfully implemented by NMMC, with high administrative coverage in slums and low-income areas. Delivery cost estimates provide important inputs to evaluate the cost-effectiveness and affordability of TCV vaccination through public sector preventive campaigns.

Successful switch (tOPV to bOPV) in India: Tribute to a resilient health system.

In accordance with the end game strategies for polio eradication a synchronized switch plan from tOPV to bOPV was implemented globally in 2016. The National Committee for Polio Eradication (NCCPE) validated the switch activities in India. An expert group of 104 academics conducted field visits in 25 states and 2 Union territories for independent verification (after an initial round of verification by the National Polio Surveillance Project [NPSP]). The objectives were to validate withdrawal and disposal of tOPV by screening cold chain points in public and private sector health facilities in both rural and urban areas; additionally, availability of bOPV and IPV was also documented. 34 filled tOPV and 5 empty vials were detected inside cold chain equipment and 17 outside. The disposal mechanism was found to be reasonably adequate. The key strategies -- 'throttling' of vaccine supplies well ahead of the switch date while preventing stock outs at various immunization points, simultaneously working with the regulators to delicense the tOPV on the switch date and helping manufacturers to calibrate vaccine production according to national timelines, and strong and persistent advocacy with professional associations to align with national bOPV and IPV policy facilitated successful accomplishment of the switch process. Effective implementation of the switch strategy in India also bears testimony to the resilience of the health system operating under diverse and heterogeneous governance.

Successes and challenges of expansion of environmental poliovirus surveillance in the WHO South-East Asia Region.

The last decade has witnessed an exponential expansion of environmental surveillance (ES) of poliovirus in sewage samples in the World Health Organization (WHO) South-East Asia Region. This has grown from only three sites in Mumbai, India in 2001 to 56 sites in 2017 in Bangladesh, India, Indonesia, Myanmar, Nepal and Thailand. ES is critical to the region in providing evidence of silent transmission of vaccine-derived poliovirus and Sabin-like poliovirus type 2 - especially since the global "switch" to cease use of oral polio vaccine type 2 - and for monitoring the effectiveness of containment activities. This targeted expansion of ES to supplement surveillance for acute flaccid paralysis (AFP) required quality assurance in ES procedures, improvements in the sensitivity of the laboratory-based surveillance system, and establishment of real-time data analysis for evidence-based programmes. ES in the region has provided documentary evidence for the absence of indigenous wild poliovirus in circulation and no importations via international travellers. Post-switch, while no vaccine-derived poliovirus was detected from AFP cases, ES identified five ambiguous vaccine-derived polioviruses in 2016 and early 2017, with no evidence of circulation. Future challenges include monitoring for vaccine-derived poliovirus strains shed for a prolonged time by immunodeficient individuals, and expanding ES to areas lacking sewage networks. To maintain the polio-free status of the WHO South-East Asia Region and achieve a world free of poliomyelitis, critical evaluation of immunization coverage, continued performance of surveillance for acute flaccid paralysis, and enhanced analysis of sewage samples to detect any breach in containment are essential.

Measles-Rubella Supplementary Immunization Activity Readiness Assessment - India, 2017-2018.

In 2013, during the 66th session of the Regional Committee of the World Health Organization (WHO) South-East Asia Region (SEAR), the 11 SEAR countries* adopted goals to eliminate measles and control rubella and congenital rubella syndrome by 2020† (1). To accelerate progress in India (2,3), a phased§ nationwide supplementary immunization activity (SIA)¶ using measles-rubella vaccine and targeting approximately 410 million children aged 9 months-14 years commenced in 2017 and will be completed by first quarter of 2019. To ensure a high-quality SIA, planning and preparation were monitored using a readiness assessment tool adapted from the WHO global field guide** (4) by the India Ministry of Health and Family Welfare. This report describes the results and experience gained from conducting SIA readiness assessments in 24 districts of three Indian states (Andhra Pradesh, Kerala, and Telangana) during the second phase of the SIA. In each selected area, assessments were conducted 4-6 weeks and 1-2 weeks before the scheduled SIA. At the first assessment, none of the states and districts were on track with preparations for the SIA. However, at the second assessment, two (67%) states and 21 (88%) districts were on track. The SIA readiness assessment identified several preparedness gaps; early assessment results were immediately communicated to authorities and led to necessary corrective actions to ensure high-quality SIA implementation.

Progress Toward Rubella and Congenital Rubella Syndrome Control - South-East Asia Region, 2000-2016.

In 2013, the 66th session of the Regional Committee of the World Health Organization (WHO) South-East Asia Region (SEAR)* adopted the goal of elimination of measles and control† of rubella and congenital rubella syndrome (CRS) by 2020 (1). Rubella is the leading vaccine-preventable cause of birth defects. Although rubella typically causes a mild fever and rash in children and adults, rubella virus infection during pregnancy, especially during the first trimester, can result in miscarriage, fetal death, or a constellation of congenital malformations known as CRS, commonly including visual, auditory, and/or cardiac defects, and developmental delay (2). Rubella and CRS control capitalizes on the momentum created by pursuing measles elimination because the efforts are programmatically linked. Rubella-containing vaccine (RCV) is administered as a combined measles and rubella vaccine, and rubella cases are detected through case-based surveillance for measles or fever and rash illness (3). This report summarizes progress toward rubella and CRS control in SEAR during 2000-2016. Estimated coverage with a first RCV dose (RCV1) increased from 3% of the birth cohort in 2000 to 15% in 2016 because of RCV introduction in six countries. RCV1 coverage is expected to increase rapidly with the phased introduction of RCV in India and Indonesia beginning in 2017; these countries are home to 83% of the SEAR birth cohort. During 2000-2016, approximately 83 million persons were vaccinated through 13 supplemental immunization activities (SIAs) conducted in eight countries. During 2010-2016, reported rubella incidence decreased by 37%, from 8.6 to 5.4 cases per 1 million population, and four countries (Bangladesh, Maldives, Sri Lanka, and Thailand) reported a decrease in incidence of ≥95% since 2010. To achieve rubella and CRS control in SEAR, sustained investment to increase routine RCV coverage, periodic high-quality SIAs to close immunity gaps, and strengthened rubella and CRS surveillance are needed.

Global Polio Eradication - Way Ahead.

In 1988, the World Health Assembly resolved to eradicate poliomyelitis by the year 2000. Although substantial progress was achieved by 2000, global polio eradication proved elusive. In India, the goal was accomplished in 2011, and the entire South-East Asia Region was certified as polio-free in 2014. The year 2016 marks the lowest wild poliovirus type 1 case count ever, the lowest number of polio-endemic countries (Afghanistan, Nigeria and Pakistan), the maintenance of wild poliovirus type 2 eradication, and the continued absence of wild poliovirus type 3 detection since 2012. The year also marks the Global Polio Eradication Initiative (GPEI) moving into the post-cessation of Sabin type 2, after the effort of globally synchronized withdrawal of Sabin type 2 poliovirus in April 2016. Sustained efforts will be needed to ensure polio eradication is accomplished, to overcome the access and security issues, and continue to improve the quality and reach of field operations. After that, surveillance (the "eyes and ears") will move further to the center stage. Sensitive surveillance will monitor the withdrawal of all Sabin polioviruses, and with facility containment, constitute the cornerstones for eventual global certification of wild poliovirus eradication. An emergency response capacity is essential to institute timely control measures should polio still re-emerge. Simultaneously, the public health community needs to determine whether and how to apply the polio-funded infrastructure to other priorities (after the GPEI funding has stopped). Eradication is the primary goal, but securing eradication will require continued efforts, dedicated resources, and a firm commitment by the global public health community.

The Switch From Trivalent to Bivalent Oral Poliovirus Vaccine in the South-East Asia Region.

This analysis describes an innovative and successful approach to risk identification and mitigation in relation to the switch from trivalent to bivalent oral polio vaccine (OPV) in the 11 countries of the World Health Organization's (WHO's) South-East Asia Region (SEAR) in April 2016.The strong commitment of governments and immunization professionals to polio eradication and an exemplary partnership between the WHO, United Nations Children's Fund (UNICEF), and other partners and stakeholders in the region and globally were significant contributors to the success of the OPV switch in the SEAR. Robust national switch plans were developed and country-specific innovations were planned and implemented by the country teams. Close monitoring and tracking of the activities and milestones through dashboards and review meetings were undertaken at the regional level to ensure that implementation time lines were met, barriers identified, and solutions for overcoming challenges were discussed and implemented.The SEAR was the first WHO Region globally to complete the switch and declare the successful withdrawal of trivalent OPV from all countries on 17 May 2016.A number of activities implemented during the switch process are likely to contribute positively to existing immunization practices and to similar initiatives in the future. These activities include better vaccine supply chain management, improved mechanisms for disposal of vaccination-related waste materials, and a closer collaboration with drug regulators, vaccine manufacturers, and the private sector for immunization-related initiatives.

Progress Toward Measles Elimination - Bangladesh, 2000-2016.

In 2013, at the 66th session of the Regional Committee of the World Health Organization (WHO) South-East Asia Region (SEAR), a regional goal was established to eliminate measles and control rubella and congenital rubella syndrome* by 2020 (1). WHO-recommended measles elimination strategies in SEAR countries include 1) achieving and maintaining ≥95% coverage with 2 doses of measles-containing vaccine (MCV) in every district, delivered through the routine immunization program or through supplementary immunization activities (SIAs)†; 2) developing and sustaining a sensitive and timely measles case-based surveillance system that meets targets for recommended performance indicators; and 3) developing and maintaining an accredited measles laboratory network (2). In 2014, Bangladesh, one of 11 countries in SEAR, adopted a national goal for measles elimination by 2018 (2,3). This report describes progress and challenges toward measles elimination in Bangladesh during 2000-2016. Estimated coverage with the first MCV dose (MCV1) increased from 74% in 2000 to 94% in 2016. The second MCV dose (MCV2) was introduced in 2012, and MCV2 coverage increased from 35% in 2013 to 93% in 2016. During 2000-2016, approximately 108.9 million children received MCV during three nationwide SIAs conducted in phases. During 2000-2016, reported confirmed measles incidence decreased 82%, from 34.2 to 6.1 per million population. However, in 2016, 56% of districts did not meet the surveillance performance target of ≥2 discarded nonmeasles, nonrubella cases§ per 100,000 population. Additional measures that include increasing MCV1 and MCV2 coverage to ≥95% in all districts with additional strategies for hard-to-reach populations, increasing sensitivity of measles case-based surveillance, and ensuring timely transport of specimens to the national laboratory will help achieve measles elimination.

Japanese Encephalitis Surveillance and Immunization - Asia and Western Pacific Regions, 2016.

Japanese encephalitis (JE) virus is the most important vaccine-preventable cause of encephalitis in the Asia-Pacific region. The World Health Organization (WHO) recommends integration of JE vaccination into national immunization schedules in all areas where the disease is a public health priority (1). This report updates a previous summary of JE surveillance and immunization programs in Asia and the Western Pacific in 2012 (2). Since 2012, funding for JE immunization has become available through the GAVI Alliance, three JE vaccines have been WHO-prequalified,* and an updated WHO JE vaccine position paper providing guidance on JE vaccines and vaccination strategies has been published (1). Data for this report were obtained from a survey of JE surveillance and immunization practices administered to health officials in countries with JE virus transmission risk, the 2015 WHO/United Nations Children's Fund Joint Reporting Form on Immunization, notes and reports from JE meetings held during 2014-2016, published literature, and websites. In 2016, 22 (92%) of 24 countries with JE virus transmission risk conducted JE surveillance, an increase from 18 (75%) countries in 2012, and 12 (50%) countries had a JE immunization program, compared with 11 (46%) countries in 2012. Strengthened JE surveillance, continued commitment, and adequate resources for JE vaccination should help maintain progress toward prevention and control of JE.