Measles outbreaks increased worldwide during 2017-19. The largest outbreak in the World Health Organisation Western Pacific region occurred in the Philippines where first-dose measles-containing vaccine (MCV1) coverage had reduced to 75% in 2018. The aim of this study was to summarise paediatric measles admissions to the national infectious diseases referral hospital in Manila during 2016 to 2019. A retrospective single-centre observational study including 5,562 children aged under five years admitted with measles from January 2016 to December 2019. We summarised sociodemographic and clinical characteristics, vaccine status, reported exposures, and outcomes. Univariable and multivariable logistic regression analyses were undertaken to assess associations between different characteristics of hospitalised children and death. The median age of children hospitalised with measles was 11 months (interquartile range: 7-28). 84·5% of cases were reported not to have received any MCV. The risk of mortality was 3·2%, with 41% of deaths occurring among children aged less than 9 months. No children died who had received two MCV. The following characteristics were significantly associated with mortality in the multivariable analysis: age group, residence outside of the national capital region, not having received any MCV, duration between onset of fever and hospital admission of 7-14 days compared with 0-3 days, not receiving vitamin A supplementation, having pneumonia, and gastroenteritis. The Philippines remains at risk of future measles epidemics. Routine immunization needs to be strengthened and earlier timing of MCV1 requires further evaluation to reduce measles incidence and mortality.

Cross-reactive antibodies to epitopes that span envelope proteins on the virion surface are hypothesized to protect against dengue virus (DENV) infection and disease. Here, we measured antibodies targeting a quaternary epitope called the envelope dimer epitope (EDE) as well as neutralizing and binding antibodies and evaluated their association with DENV infection, vaccine response, and disease outcome in dengue-vaccinated ( n = 164) and dengue-unvaccinated children ( n = 88) within a longitudinal cohort in Cebu, Philippines ( n = 2996). Antibodies targeting EDE were prevalent and associated with broad neutralization of mature DENV1 to DENV4 virions in those with evidence of at least two prior DENV infections but were mostly absent in those with only one prior infection. Subsequent infection and vaccination boosted titers of EDE-like antibodies, neutralizing antibodies, and DENV-binding antibodies. EDE-like antibodies were associated with reduced risk of symptomatic dengue and more severe dengue and statistically explained the protective effect of binding and neutralizing antibodies on dengue. Thus, antibodies targeting quaternary epitopes help explain the broad cross-protection observed in those with multiple prior DENV exposures, making them useful for evaluation and development of future vaccines and therapeutics.

The COVID-19 global pandemic is entering its second year. In this short report we present additional results as a supplement to our previous paper on COVID-19 and common respiratory virus screening for healthcare workers (HCWs) in a tertiary infectious disease referral hospital in Manila, Philippines. We sought to understand what etiologic agents could explain the upper/lower respiratory tract infection-like (URTI/LRTI-like) symptoms exhibited by 88% of the 324 HCWs tested. Among the patients who had URTI/LRTI-like symptoms, only seven (2%) were positive for COVID-19, while 38 (13%) of the symptomatic participants were identified positive for another viral etiologic agent. Rhinovirus was the most common infection, with 21 (9%) of the symptomatic participants positive for rhinovirus. Based on these results, testing symptomatic HCWs for common respiratory illnesses in addition to COVID-19 should be considered during this time of global pandemic.

Background: SARS-CoV-2 seroepidemiological studies are used to guide public health decision making and to prepare for emerging infectious diseases. Disease occurrence estimates are limited in the Philippines, the country with the highest reported number of coronavirus disease-related deaths in the Western Pacific region. We aimed to estimate SARS-CoV-2 seroprevalence and infection rate among outpatient clinic attendees in Metro Manila prior to the implementation of the national coronavirus disease vaccination program. Methods: We conducted repeated cross-sectional surveys at the animal bite clinic in San Lazaro Hospital, Manila, the Philippines across four periods, 3 months apart, between May 2020 and March 2021. Multivariable logistic regression was used to assess associations between different characteristics and infection status including seropositivity. Results: In total 615 participants were enrolled, ranging from 115 to 174 per period. Seroprevalence quadrupled between the first (11.3%) and second (46.8%) periods and plateaued thereafter (third—46.0%, fourth—44.6%). Among seropositive participants, total antibody concentration was comparable throughout the first to third periods but declined between the third and fourth periods. Infection prevalence was comparable across enrollment periods (range 2.9–9.5%). Post-secondary education [aOR 0.42 (95% CI 0.26, 0.67)] was protective, and frontline work [aOR 1.81 (95% CI 1.18, 2.80)] was associated with increased odds of seropositivity. Frontline work status [aOR 2.27 (95% CI 1.10, 4.75)] and large household size [aOR 2.45 (95% CI 1.18, 5.49)] were associated with increased odds of infection. Conclusions: The quadrupling of seroprevalence over 3 months between the first and second enrollment periods coincided with the high burden of infection in Metro Manila in early 2020. Our findings suggest a limit to the rise and potential decline of population-level SARS-CoV-2 infection-induced immunity without introduction of vaccines. These results may add to our understanding of how immunity develops against emerging infectious diseases including coronaviruses.

Introduction: Climate change poses significant health risks globally, particularly in vulnerable countries like the Philippines. This scoping review examines recent research trends (2018–2023) on the health impacts of climate change in the Philippines, building on previous national reviews and situating findings within global evidence.Methods: We screened 8,346 articles from various databases and identified 69 studies meeting inclusion criteria. Using a framework-guided thematic synthesis, studies were categorized into 6 themes: vulnerability to disease and injury, direct health impacts of climate and weather, ecosystem-mediated impacts, health impacts mediated through human institutions, adaptation strategies, and co-benefits of mitigation measures.Results: Results reveal a significant increase in climate-health research compared to a previous review (1980–2017), with notable growth in studies in mental health, gender-based vulnerabilities, and adaptation measures. However, research remains geographically concentrated in Luzon, highlighting regional disparities, and few studies utilized long-term climate-health datasets. Studies quantifying the health co-benefits of mitigation measures also remain limited.Discussion: This review demonstrates significant progress while identifying persistent gaps. Future research should prioritize long-term surveillance, local adaptation evaluations and health-economic co-benefits studies to strengthen climate-health data integration, improve climate information services and develop equity-oriented, policy-relevant research agenda.