Hepatitis B surface antigen seroprevalence among children in the Philippines, 2018.

The World Health Organization Western Pacific Region (WPR) set a hepatitis B virus (HBV) control target to achieve HBV surface antigen (HBsAg) prevalence of <1% among children aged 5 years by 2017. The estimated HBsAg prevalence in the Philippines among adults was 16.7% during the pre-vaccine era. We estimated the HBsAg seroprevalence among children aged 5-7 years to measure the impact of vaccination. We conducted a household serosurvey, using a three-stage cluster survey methodology (provinces, clusters, and households). We estimated HBsAg prevalence using a rapid, point-of-care HBsAg test and calculated vaccination coverage by reviewing vaccination records or by caregiver recall. A questionnaire was administered to assess demographic variables for the child and family. We assessed the association between chronic HBV infection, vaccination coverage, and demographic variables, accounting for the complex survey design. Of the 2178 children tested, HBsAg was detected in 15 children [0.8%, 95% confidence interval (CI): 0.4, 1.7]. Only two of the HBsAg-positive children had been fully vaccinated against HBV. Based on documented vaccination or caregiver recall for the survey population, hepatitis B vaccine birth dose (HepB-BD) coverage was 53%, and the third dose hepatitis B vaccination (HepB3) coverage was 73 percent. Among the 1362 children with documented HepB-BD, timely HepB-BD coverage (given within 24 h of birth) was 43%; children born outside a health facility were less likely to receive a timely HepB-BD than those born in a health facility (adjusted odds ratio 0.10, 95% CI: 0.04, 0.23). HBsAg prevalence among children in the Philippines has decreased compared to the prevalence among adults in the pre-vaccination era. Strategies to further reduce HBsAg prevalence include ensuring that all children, whether born in health facilities or at home, receive a timely HepB-BD, and increasing HepB-BD and HepB3 coverage to reach the WPR goals of ≥95% coverage.

Non-polio enteroviruses among healthy children in the Philippines.

BACKGROUND: Enteroviruses (EVs) are most commonly associated with either mild or asymptomatic infections, however, the presence of silent carriers in the community has been proven to play a crucial role in the spread of diseases such as hand, foot, and mouth disease (HFMD) that records high incidence in Asia Pacific region. In the Philippines, limited information is available on the etiology and prevalence of enterovirus outside the Acute Flaccid Paralysis (AFP) surveillance, thus, a study to determine the baseline prevalence of Non-Polio Enteroviruses (NPEVs) among healthy Filipino children was conducted. METHODS: A descriptive, cross-sectional study was performed to determine the prevalence of NPEV among healthy children under 6 years old in the Philippines. Duplicate stool samples were collected from 360 healthy children residing in three major urban cities in the country. Virus isolation and polymerase chain reaction were performed to identify enteroviruses present in the samples. To determine if the results of the study are comparable to the AFP surveillance data, the results of the study were compared to the prevalence and isolation rate among AFP cases of the similar cases collected the same year. RESULTS: Prevalence of enteroviruses among healthy children was found to be at 24.7%. Comparing the NPEV rates from the study and AFP surveillance of similar age and the same year of collection, there was no significant difference in NPEV case prevalence. The study identified a total of 19 different enterovirus serotypes with majority belonging to species Enterovirus B (EV-B). CONCLUSION: The study was able to establish a baseline NPEV case prevalence of 24.7% among healthy children aged under 6 years old in three major urban sites in the Philippines. The high isolation of NPEV among healthy children signifies continuous fecal-oral transmission of enteroviruses in the community.

Molecular characterization of rotavirus diarrhea among children aged under five years in the Philippines, 2013-2015.

With the availability of new and existing rotavirus vaccines, credible and reliable data on burden of rotavirus-associated disease are needed to enable evidence-based decision making regarding the introduction of rotavirus vaccines. The national rotavirus surveillance program in the Philippines, a sentinel-based surveillance, was established in 2012 to determine the proportion of laboratory-confirmed rotavirus cases among children under five years with acute gastroenteritis and to describe the geographic distribution and molecular epidemiology of rotavirus in the country. During 2013 to 2015, rotavirus infection was the cause of acute gastroenteritis among children under five years admitted to hospitals or evaluated in emergency rooms, constituting more than one-third of gastroenteritis hospitalizations at the sentinel site hospitals. The predominant genotype observed was G1P[8]. Although a rotavirus surveillance network has been established, findings suggest the need to strengthen the network in the country and to continue monitoring prevalent rotavirus strains to help identify the possible emergence of new strains.

Using the World Health Organization Measles Programmatic Risk Assessment Tool for Monitoring of Supplemental Immunization Activities in the Philippines.

In 2012, the World Health Organization Regional Committee for the Western Pacific Region (WPR) reaffirmed its commitment to eliminate measles and urged WPR member states to interrupt endemic measles virus transmission as rapidly as possible. In 2013, a large measles outbreak occurred in the Philippines despite implementation of measles elimination strategies including a nationwide supplemental immunization activity (SIA) in 2011 using measles- and rubella-containing vaccine and targeting children aged nine months to seven years. To prevent future measles outbreaks a new tool was developed to assess district-level risk for measles outbreaks, based on the WPR polio risk assessment tool previously applied in the Philippines. Risk was assessed as a function of combined indicator scores from four data input categories: population immunity, surveillance quality, program performance, and threat assessment. On the basis of the overall score, the tool assigned each district a risk category of low, medium, high, or very high. Of the 122 districts and highly urbanized cities in the Philippines, 58 (48%) were classified as high risk or very high risk, including the district of the Metro Manila area and Region 4A where the outbreak began in 2013. Risk assessment results were used to guide the monitoring and supervision during the nationwide SIA conducted in 2014. The initial tool drafted in the Philippines served as a template for development of the global risk assessment tool. Regular annual measles programmatic risk assessments can be used to help plan risk mitigation activities and measure progress toward measles elimination.

Progress toward measles elimination­Philippines, 1998-2014.

In 2005, the Regional Committee for the World Health Organization (WHO) Western Pacific Region (WPR) established a goal to eliminate measles by 2012.The recommended elimination strategies in WPR include 1) ≥95% 2-dose coverage with measles-containing vaccine (MCV) through routine immunization services and supplementary immunization activities (SIAs); 2) high-quality case-based measles surveillance; 3) laboratory surveillance with timely and accurate testing of specimens to confirm or discard suspected cases and detect measles virus genotypes; and 4) measles outbreak preparedness, rapid response, and appropriate case management. In the WPR, the Philippines set a national goal in 1998 to eliminate measles by 2008. This report describes progress toward measles elimination in the Philippines during 1998-2014 and challenges remaining to achieve the goal. WHO-United Nations Children's Fund (UNICEF)-estimated coverage with the routine first dose of MCV (MCV1) increased from 80% in 1998 to 90% in 2013, and coverage with the routine second dose of MCV (MCV2) increased from 10% after nationwide introduction in 2010 to 53% in 2013. After nationwide SIAs in 1998 and 2004, historic lows in the numbers and incidence of reported measles cases occurred in 2006. Despite nationwide SIAs in 2007 and 2011, the number of reported cases and incidence generally increased during 2007-2012, and large measles outbreaks occurred during 2013-2014 that affected infants, young children, older children, and young adults and that were prolonged by delayed and geographically limited outbreak response immunization activities during 2013-2014. For the goal of measles elimination in WPR to be achieved, sustained investments are required in the Philippines to strengthen health systems, implement the recommended elimination strategies, and develop additional strategies to identify and reduce measles susceptibility in specific geographic areas and older age groups.

Findings from a hepatitis B birth dose assessment in health facilities in the Philippines: opportunities to engage the private sector.

BACKGROUND: Hepatitis B vaccination in the Philippines was introduced in 1992 to reduce the high burden of chronic hepatitis B virus (HBV) infection in the population; in 2007, a birth dose (HepB-BD) was introduced to decrease perinatal HBV transmission. Timely HepB-BD coverage, defined as doses given within 24h of birth, was 40% nationally in 2011. A first step in improving timely HepB-BD coverage is to ensure that all newborns born in health facilities are vaccinated. METHODS: In order to assess ways of improving the Philippines' HepB-BD program, we evaluated knowledge, attitudes, and practices surrounding HepB-BD administration in health facilities. Teams visited selected government clinics, government hospitals, and private hospitals in regions with low reported HepB-BD coverage and interviewed immunization and maternity staff. HepB-BD coverage was calculated in each facility for a 3-month period in 2011. RESULTS: Of the 142 health facilities visited, 12 (8%) did not provide HepB-BD; seven were private hospitals and five were government hospitals. Median timely HepB-BD coverage was 90% (IQR 80%-100%) among government clinics, 87% (IQR 50%-97%) among government hospitals, and 50% (IQR 0%-90%) among private hospitals (p=0.02). The private hospitals were least likely to receive supervision (53% vs. 6%-31%, p=0.0005) and to report vaccination data to the national Expanded Programme on Immunization (36% vs. 96%-100%, p<0.0001). CONCLUSIONS: Private sector hospitals in the Philippines, which deliver 18% of newborns, had the lowest timely HepB-BD coverage. Multiple avenues exist to engage the private sector in hepatitis B prevention including through existing laws, newborn health initiatives, hospital accreditation processes, and raising awareness of the government's free vaccine program.

A comparison of vital registration and reproductive-age mortality survey in Bukidnon, Philippines, 2008.

OBJECTIVE: To determine the accuracy of reported maternal deaths for 2008 in a province in the Philippines. METHODS: A reproductive-age mortality survey (RAMOS) was conducted to identify deaths of women aged 15-49 years from Bukidnon, Philippines, in 2008. Sources included various health and community reporting units. Verbal autopsies were carried out to ascertain maternal deaths. RESULTS: The survey found 58 pregnancy-related deaths in 2008, of which 52 were maternal deaths. Of the 52, 14 were found in local civil registries but 4 were not classified as maternal deaths. No single reporting unit identified all deaths. Local civil registries provided an estimated maternal mortality ratio (MMR) of 49 per 100000 live births. The present RAMOS estimated an MMR of 209 (95% confidence interval, 191-226) per 100000 live births. CONCLUSION: Official reports led people using the data to believe that the MMR in the province was on track for Millennium Development Goal 5 (to reduce MMR by three-quarters by 2015). The present survey showed that local civil registries missed three-quarters of all maternal deaths. All countries engaged in addressing maternal mortality reduction should consider similar approaches to improve data quality.