Maintaining polio-free certification in the World Health Organization Western Pacific Region for over a decade.

On 29 October 2000, the World Health Organization (WHO) Regional Commission for the Certification of Poliomyelitis Eradication in the Western Pacific certified the WHO Western Pacific Region as free of indigenous wild poliovirus. This status has been maintained to date: wild poliovirus importations into Singapore (in 2006) and Australia (in 2007) did not lead to secondary cases, and an outbreak in China (in 2011) was rapidly controlled. Circulation of vaccine derived polioviruses in Cambodia, China and the Philippines was quickly interrupted. A robust acute flaccid paralysis surveillance system, including a multitiered polio laboratory network, has been maintained, forming the platform for integrating measles, neonatal tetanus, and other vaccine-preventable disease surveillance and their respective control goals. While polio elimination remains one of the most important achievements in public health in the Western Pacific Region, extended delays in global eradication have, however, led to shifting and competing public health priorities among member states and partners and have made the region increasingly vulnerable.

Are we there yet? Assessing achievement of vaccine-preventable disease goals in WHO's Western Pacific Region.

Accelerated disease control goals have long been appreciated for their role in galvanizing commitment and bringing a sense of urgency for disease prevention. WHO's Western Pacific Region has 14 on-going communicable disease reduction goals including 1 targeting eradication, 10 targeting elimination, and 3 control initiatives. These goals cover mother-to-child transmission of HIV, congenital syphilis, tuberculosis, leprosy, five parasitic diseases and four vaccine-preventable diseases (VPD). The initiatives have distinct objectives, approaches, and means in which to measure achievement of the goals. Given the long history and experience with VPD initiatives in the Western Pacific Region, this manuscript focuses on the Region's following initiatives: (1) smallpox eradication, (2) polio eradication, (3) measles elimination, (4) maternal and neonatal tetanus elimination (MNTE), and (5) hepatitis B control. There is good consistency across the Region's VPD initiatives yet a pattern of more robust and representative data requirements, stricter evaluation criteria, and more formal evaluation bodies are linked to the intensity of the goal - with eradication being the peak. On the other end of this spectrum, the Regional hepatitis B control initiative has established efficient and low-cost approaches for measuring impact and evaluating if the goals have been met. Even within the confines of VPD initiatives there are some deviations in use of terminology and comparisons across other disease control initiatives in the Region are provided.

Hepatitis B control in the World Health Organization's Western Pacific Region: targets, strategies, status.

WHO's Western Pacific Region has the highest rates of hepatitis B virus (HBV) infection in the world; most countries have >8% prevalence of HBV chronic infection in their adult population. In 2005, Member States of the Region adopted a resolution to reduce chronic hepatitis B infection prevalence to less than 2% among children by 2012 as an interim milestone toward a regional goal of less than 1% prevalence. Country commitments to hepatitis B control and successes represent a remarkable public health achievement by preventing over 1 million chronic infections and 300,000 HBV-related deaths per birth cohort. Reported here is a review of the process and strategies for translating this public health initiative into practice including such activities as setting up an Expert Resource Panel, developing implementation guidelines, focusing on facility births while supporting efforts to reach home births, providing guidance for conducting seroprevalence surveys, and establishing a verification process.

Progress and challenges for measles elimination by 2012 in the Western Pacific Region.

BACKGROUND: The 37 countries and areas of the World Health Organization (WHO) Western Pacific Region have targeted measles for elimination by 2012. METHODS: We reviewed routine and supplementary immunization coverage based on 2010 WHO/United Nation's Children's Fund (UNICEF) estimates and Joint Reporting Forms and epidemiologic and laboratory data submitted by the countries and areas. RESULTS: In 2009, 21 of 37 countries and areas had ≥90% coverage with a first dose of measles vaccine; 32 countries and areas provided 2 routine doses of measles vaccine with 94% weighted average coverage among those reporting. From 1996 to 2009, 235 million persons received measles vaccine during 94 immunization campaigns in 30 countries and areas. As of 2009, 2.8 suspected cases per 100,000 population were discarded as nonmeasles; however, only 43% of second level administrative units reported at least 1 discarded case per 100,000. Adequate specimen collection rate was 71%. Measles incidence was 34 per million population in 2009, a 58% decrease compared with 2008 and the lowest ever reported. As many as 25 countries and areas already may have eliminated measles. CONCLUSIONS: Achieving the 2012 measles elimination goal is feasible provided political and financial commitments are increased at every level to further improve routine and supplementary immunization activity (SIA) coverage and surveillance in every district.

Epidemiology of a measles epidemic in Vietnam 2008-2010.

BACKGROUND: Vietnam conducted a measles catch-up supplementary immunization activity (SIA) during 2002-2003 that targeted children 9 months-10 years of age, followed by subnational SIAs targeting persons up to 20 years of age during 2004 and 2007-2008. A measles epidemic began among young adults in October 2008 in the northern region, spread nationwide during early 2009, and continued during 2010. METHODS: We reviewed national epidemiologic and laboratory surveillance data. Measles cases were defined and classified according to World Health Organization recommendations. RESULTS: From October 2008 through January 2010, 7948 confirmed measles cases were reported from 60 of 63 provinces, an incidence of 93 cases per million population. Incidence was 328 cases per million population among children age 1-4 years, 318 cases per million population among infants, and 271 cases per million population among persons aged 20-24 years. Few cases were reported among persons 7-17 or >27 years of age. Median age of cases trended downward over time in all regions. CONCLUSIONS: The 2002-2003 measles SIA protected its targeted age group, but this epidemic was not prevented by follow-up subnational SIAs in selected provinces during 2007-2008. Transmission began among young adults and was sustained among children. The outcome of Vietnam's 2010 SIA targeting children only and change in routine schedule may influence elimination strategies for other countries.

Diarrhea and ARI in rural areas of Bangladesh.

In Bangladesh, one third of the total child death burden is due to diarrhea. Every year, a rural child suffers on average from 4.6 episodes of diarrhea, from which about 230,000 children die. In this study, information was collected from 8,287 children under five years of age and 7,082 caretakers in 120 clusters chosen by a two-stage random cluster sampling method. As compared to the baseline survey, carried out in 1996, children now are about 30% less likely to suffer from diarrhea, and the risk of dying has been reduced by 60%. Although the 2-weeks prevalence of acute respiratory infection (ARI) has risen from 39% (1996) to 46% and that of Acute Respiratory Infections needing assessment (ANA) from 12.4% to 16.9%, now more caretakers (59.9%) than in 1996 (56.7%) are able to identify correctly danger signs for seeking care and 58.4% (1996: 46.6%) of parents seek help when danger signs are present. Similar for diarrhea and ARI, village doctors and traditional healers are most frequently sought for help by caretakers; government health centers and hospitals are sought to a much lesser degree. Since 1996, intervention activities were implemented for four years in the study area using an IEC strategy. This strategy included raising awareness and training of health personnel, NGO personnel and village volunteers, especially women. Diarrhea issues were included in school health education with emphasis on practical exercises of diarrhea management. For all target groups (health personnel, village volunteers, NGOs, mothers and school children) specific education material was developed and deployed. In the political arena, women leaders who are part of the local government were included in an awareness-raising campaign. The results of the study undertaken over four years later show that in a relatively short time behavior of mostly poor and illiterate caretakers can be changed leading to a significant reduction of ARI mortality and diarrhea morbidity, and mortality in children.