A New Method for Estimating the Coverage of Mass Vaccination Campaigns Against Poliomyelitis From Surveillance Data.

Mass vaccination campaigns with the oral poliovirus vaccine targeting children aged <5 years are a critical component of the global poliomyelitis eradication effort. Monitoring the coverage of these campaigns is essential to allow corrective action, but current approaches are limited by their cross-sectional nature, nonrandom sampling, reporting biases, and accessibility issues. We describe a new Bayesian framework using data augmentation and Markov chain Monte Carlo methods to estimate variation in vaccination coverage from children's vaccination histories investigated during surveillance for acute flaccid paralysis. We tested the method using simulated data with at least 200 cases and were able to detect undervaccinated groups if they exceeded 10% of all children and temporal changes in coverage of ±10% with greater than 90% sensitivity. Application of the method to data from Pakistan for 2010-2011 identified undervaccinated groups within the Balochistan/Federally Administered Tribal Areas and Khyber Pakhtunkhwa regions, as well as temporal changes in coverage. The sizes of these groups are consistent with the multiple challenges faced by the program in these regions as a result of conflict and insecurity. Application of this new method to routinely collected data can be a useful tool for identifying poorly performing areas and assisting in eradication efforts.

Pakistan's fight against poliomyelitis: introducing innovative strategies to address challenges and attain the goal of eradication.

Pakistan, with Nigeria, India and Afghanistan, is one of the four remaining polio endemic countries in the world. Since the start of polio eradication initiative in 1994, the country has succeeded in reducing the number of polio cases from an estimated 20,000 annually to 89 in 2009. Furthermore, persistent transmission is largely localized to three transmission zones in which ten of the fifteen highest risk areas are situated. Insecurity, operational issues, governance lapses, low routineimmunization coverage, inadequate trickle-down of the political commitment existing at the national level to sub-national level and extensive population movement are the main barriers to the process. A robust strategic plan was developed for 2010-2012 encompassing district-specific plans and focused strategy on securitycompromised areas, performance-based payment, independent monitoring, attention to migratory populations, social mobilization, and strategic cooperation with Afghanistan. This will provide Pakistan a strong and imminent opportunity to interrupt polio virus circulation.

A review of EPI progress in Pakistan towards achieving coverage targets: present situation and the way forward.

Pakistan's Expanded Programme on Immunization (EPI) performance has a significant impact on global and regional immunization indicators such as poliomyelitis eradication, maternal and neonatal tetanus and measles elimination. Despite significant efforts by the Government and partners, Pakistan's immunization indicators have not met the expected benchmarks. Barriers to achieving immunization goals are related to limited access to immunization services, lack of parent awareness and weak management. With sustained Government commitment, predictable partner support and by adopting effective strategies, Pakistan can achieve the immunization targets set at the regional and global level and make strong progress towards achieving Millennium Development Goal 4. This paper reviews EPI coverage targets, constraints, costs and resource allocation, and financial impact of suboptimal performance, and indicates the way forward to overcome these challenges.

A review of EPI progress in Pakistan towards achieving coverage targets: present situation and the way forward

Pakistan's Expanded Programme on Immunization [EPI] performance has a significant impact on global and regional immunization indicators such as poliomyelitis eradication, maternal and neonatal tetanus and measles elimination. Despite significant efforts by the Government and partners, Pakistan's immunization indicators have not met the expected benchmarks. Barriers to achieving immunization goals are related to limited access to immunization services, lack of parent awareness and weak management. With sustained Government commitment, predictable partner support and by adopting effective strategies, Pakistan can achieve the immunization targets set at the regional and global level and make strong progress towards achieving Millennium Development Goal 4. This paper reviews EPI coverage targets, constraints, costs and resource allocation, and financial impact of suboptimal performance, and indicates the way forward to overcome these challenges

Pakistan's fight against poliomyelitis: introducing innovative strategies to address challenges and attain the goal of eradication

Pakistan, with Nigeria, India and Afghanistan, is one of the four remaining polio endemic countries in the world. Since the start of polio eradication initiative in 1994, the country has succeeded in reducing the number of polio cases from an estimated 20,000 annually to 89 in 2009. Furthermore, persistent transmission is largely localized to three transmission zones in which ten of the fifteen highest risk areas are situated. Insecurity, operational issues, governance lapses, low routine immunization coverage, inadequate trickle-down of the political commitment existing at the national level to subnational level and extensive population movement are the main barriers to the process. A robust strategicplan was developed for 2010-2012 encompassing district-specific plans and focused strategy on securitycompromised areas, performance-based payment, independent monitoring, attention to migratory populations, social mobilization, and strategic cooperation with Afghanistan. This will provide Pakistan a strong and imminent opportunity to interrupt polio virus circulation