Poor growth and pneumonia seasonality in infants in the Philippines: cohort and time series studies

Incidence and seasonality of Kawasaki disease in children in the Philippines, and its association with ambient air temperature

Background

Despite an unknown cause, Kawasaki disease (KD) is currently the primary leading cause of acquired heart disease in developed countries in children and has been increasing in recent years. Research efforts have explored environmental factors related to KD, but they are still unclear especially in the tropics. We aimed to describe the incidence of KD in children, assess its seasonality, and determine its association with ambient air temperature in the National Capital Region (NCR), Philippines from January 2009 to December 2019.

Methods

Monthly number of KD cases from the Philippine Pediatric Society (PPS) disease registry was collected to determine the incidence of KD. A generalized linear model (GLM) with quasi-Poisson regression was utilized to assess the seasonality of KD and determine its association with ambient air temperature after adjusting for the relevant confounders.

Results

The majority of KD cases (68.52%) occurred in children less than five years old, with incidence rates ranging from 14.98 to 23.20 cases per 100,000 population, and a male-to-female ratio of 1.43:1. Seasonal variation followed a unimodal shape with a rate ratio of 1.13 from the average, peaking in March and reaching the lowest in September. After adjusting for seasonality and long-term trend, every one-degree Celsius increase in the monthly mean temperature significantly increased the risk of developing KD by 8.28% (95% CI: 2.12%, 14.80%). Season-specific analysis revealed a positive association during the dry season (RR: 1.06, 95% CI: 1.01, 1.11), whereas no evidence of association was found during the wet season (RR: 1.10, 95% CI: 0.95, 1.27).

Conclusion

We have presented the incidence of KD in the Philippines which is relatively varied from its neighboring countries. The unimodal seasonality of KD and its linear association with temperature, independent of season and secular trend, especially during dry season, may provide insights into its etiology and may support enhanced KD detection efforts in the country.

Drivers of respiratory syncytial virus seasonal epidemics in children under 5 years in Kilifi, coastal Kenya

Respiratory syncytial virus (RSV) causes significant childhood morbidity and mortality in the developing world. The determinants of RSV seasonality are of importance in designing interventions. They are poorly understood in tropical and sub-tropical regions in low- and middle-income countries. Our study utilized long-term surveillance data on cases of RSV associated with severe or very severe pneumonia in children aged 1 day to 59 months admitted to the Kilifi County Hospital. A generalized additive model was used to investigate the association between RSV admissions and meteorological variables (maximum temperature, rainfall, absolute humidity); weekly number of births within the catchment population; and school term dates. Furthermore, a time-series-susceptible-infected-recovered (TSIR) model was used to reconstruct an empirical transmission rate which was used as a dependent variable in linear regression and generalized additive models with meteorological variables and school term dates. Maximum temperature, absolute humidity, and weekly number of births were significantly associated with RSV activity in the generalized additive model. Results from the TSIR model indicated that maximum temperature and absolute humidity were significant factors. Rainfall and school term did not yield significant relationships. Our study indicates that meteorological parameters and weekly number of births potentially play a role in the RSV seasonality in this region. More research is required to explore the underlying mechanisms underpinning the observed relationships.

Climate impacts on air quality and child health and wellbeing: Implications for Oceania

Despite the enormous gains in reducing child mortality resulting from the United Nations Millennium Development Goals, in some ways children's future wellbeing has never been under greater threat. Climate and environmental change, primarily driven by poor air quality, represents a major threat to child health and wellbeing, through both direct and indirect effects. Climate change has multiple environmental consequences impacting negatively on child health and wellbeing, including increases in ambient temperature, rising atmospheric carbon dioxide (CO₂₎ , altered distribution of rainfall, ocean warming, rising sea level and more frequent and severe adverse weather events. Multiple pathways link these exposures to a wide variety of adverse health outcomes. Countries in Oceania are especially likely to be subjected to the effects of increases in ambient temperature, altered distribution of rainfall, ocean warming and sea level rise. These changes pose a significant risk to children and provide a moral imperative for us to act to protect child health.

Vitamin D deficiency and severity of pneumonia in Indonesian children

Objective

To determine the prevalence of vitamin D deficiency in Indonesian children hospitalized with pneumonia and evaluate the association between vitamin D status and severity of pneumonia.

Methods

A hospital-based cross-sectional study was conducted from February 2016 to July 2017 in two district hospitals in Yogyakarta province, Indonesia. Infants and young children aged 2–59 months hospitalized with pneumonia were recruited. Serum blood samples were collected on admission and analyzed for total serum 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 concentrations using liquid chromatography-tandem mass spectrometry. Vitamin D deficiency was defined as a level of serum vitamin D <50 nmol/L. The association between vitamin D deficiency and severity of hospitalized pneumonia according to WHO criteria, including the presence of danger signs, hypoxemia (SpO2 in air below 90%), duration of hospitalization, and admission to Intensive Care Unit (ICU), was analyzed using logistic regression.

Results

133 children with WHO-defined pneumonia were enrolled in the study and 127 (96%) had their vitamin D status determined. The mean vitamin D concentration was 67 (± 24 SD) nmol/L and 19% of participants were vitamin D deficient. Age younger than 6 months was associated with prolonged hospitalization (> 5 days) and low birth weight and poor nutritional status on admission were risk factors for hypoxemia. However, vitamin D status was not associated with the presence of danger signs, duration of hospitalization, or hypoxemia.

Conclusions

One in every five children hospitalized with pneumonia was vitamin D deficient. Vitamin D status was not associated with the severity of pneumonia.

Are fathers a good substitute for mothers? Paternal care and growth rates in Shodagor children

Biparental care is a hallmark of human social organization, though paternal investment varies between and within societies. The facultative nature of paternal care in humans suggests males should invest when their care improves child survival and/or quality, though testing this prediction can be challenging because of the difficulties of empirically isolating paternal effects from those of other caregivers. Additionally, the broader context in which care is provided, vis-à-vis care from mothers and others, may lead to different child outcomes. Here, we examine the effects of paternal care on child growth among Shodagor fisher-traders, where fathers provide high levels of both additive and substitutive care, relative to mothers. We modeled seasonal z-scores and velocities for height, weight, and body mass index (BMI) outcomes using linear mixed models. Our evidence indicates that, as predicted, the context of paternal care is an important predictor of child outcomes. Results show that environmental seasonality and alloparental help contribute to a nuanced understanding of the impact of Shodagor paternal care on child physiology.

Epidemiology and Seasonality of Childhood Respiratory Syncytial Virus Infections in the Tropics

Infections caused by respiratory syncytial virus (RSV) are a major cause of morbidity and mortality in young children worldwide. Understanding seasonal patterns of region-specific RSV activity is important to guide resource allocation for existing and future treatment and prevention strategies. The decades of excellent RSV surveillance data that are available from the developed countries of the world are incredibly instructive in advancing public health initiatives in those regions. With few exceptions, these developed nations are positioned geographically across temperate regions of the world. RSV surveillance across tropical regions of the world has improved in recent years, but remains spotty, and where available, still lacks the necessary longitudinal data to determine the amount of seasonal variation expected over time. However, existing and emerging data collected across tropical regions of the world do indicate that patterns of infection are often quite different from those so well described in temperate areas. Here, we provide a brief summary regarding what is known about general patterns of RSV disease activity across tropical Asia, Africa and South America, then offer additional country-specific details using examples where multiple reports and/or more robust surveillance data have become available.

Observations of Pediatric Disease Prevalence from Pacific Partnership 2015

Pacific Partnership is an ongoing yearly humanitarian assistance mission to Pacific Rim countries. Although many case reports and surgical successes have been documented, few data have been published specifically about the primary care mission. This article analyzes outpatient pediatric data collected during Pacific Partnership 2015. Eleven different providers documented care delivered to children from birth through age 18 yr, inclusive. Personally de-identified data were entered into spreadsheets, sorted according to country visited, and analyzed with IBM SPSS software looking for disease frequency. One thousand eighty-seven pediatric patients were seen across Fiji, Papua New Guinea (PNG), and the Philippines (PI). Asthma was the first, second, and third most prevalent diagnosis in PNG, Fiji, and PI, with a relative proportion of the total patients seen at 5.4%, 7.2%, and 5%, respectively. In PI, 123 cases of upper respiratory infection were seen, more than four times the next most common diagnosis of normal exam. Thirty-six patients with scabies were seen in Fiji (number 1), with abdominal pain at number 3 (26 cases, 6.5%). Surprisingly, helminths were rarely seen, comprising the sixteenth and fourteenth most common diagnoses in Fiji and PI and only two cases in PNG. Future Pacific Partnership missions can plan medication stock, personnel assignment, equipment needs, and educational literature based on these data.

Sociodemographic, climatic variability and lower respiratory tract infections: a systematic literature review

Pneumonia is the leading cause of mortality and morbidity in developing countries, particularly for children and elderly. The main objective of this review paper is to review the epidemiological evidence about the effects of sociodemographic and climatic variability on pneumonia and other lower respiratory tract infections. A detailed literature search was conducted in PubMed and Scopus following PRISMA guidelines. The articles, which considered the effect of only climatic or both climatic and sociodemographic factors on pneumonia and other lower respiratory tract infections, included in this review. A total thirty-four relevant articles were reviewed. Of 34 studies, only 14 articles (41%) examined the joint effects of sociodemographic and climate factors on pneumonia and other lower respiratory infections while most of them (59%) assessed climate factors separately. Among these fourteen, only three articles (8.8%) considered detailed sociodemographic factors. All of the reviewed articles suggested different degrees of positive or negative relationship of temperature with pneumonia or other lower respiratory tract infections. Fifteen (44%) articles suggested an association with relative humidity and 13 (38%) with rainfall. Only 3 articles (8.8%) found a relationship with wind speed. Three articles (8.8%) considered other risk factors such as particulate matter 2.5 (PM_2.5) and particulate matter 10 (PM₁₀). One study among the reviewed articles used spatial analysis methods but this study did not examine the joint effects. Among the reviewed articles, 18 (53%) articles used different time series models, one article (3%) used spatiotemporal time series model, 8 (23%) studies used other models and rest 7 (21%) studies used simple descriptive analysis. A total of 18 studies (53%) were conducted in Asia, most of them in China. There were 6 studies (17%) in Europe and 8 studies (23%) in America (South, North and Central). In Africa and Oceania, only one study was found for each region. The joint effect of climate and sociodemographic factors on pneumonia and other lower respiratory tract infections remain to be determined and further research is highly recommended for future prevention of this important and common disease.

Respiratory syncytial virus seasonality in tropical Australia

OBJECTIVE

Respiratory syncytial virus (RSV) is most common during the rainy season in a number of low- to middle-income tropical settings, a pattern driven by seasonal changes in climate and nutrition. We investigated the seasonality of RSV in the high-income tropical setting of North Queensland, Australia.

METHODS

We used RSV hospital admissions data from Cairns and Townsville to assess the seasonality of RSV. We examined the seasonal scale associations between selected meteorological exposures and RSV admissions using cross-correlation of weekly data.

RESULTS

In both Cairns and Townsville, RSV admissions were highest in the latter half of the rainy season. In Cairns, RSV admissions were most strongly correlated with rainfall four weeks previously. In Townsville, RSV admissions were most strongly correlated with rainfall six weeks previously.

CONCLUSIONS

The seasonality of RSV in the tropical setting of North Queensland appears to be driven by seasonal variations in rainfall. Further research is needed to assess the impact of climate on RSV incidence in the tropics.

Incidence and Risk Factors of Childhood Pneumonia-Like Episodes in Biliran Island, Philippines--A Community-Based Study

Pneumonia is a leading cause of deaths in infants and young children in developing countries, including the Philippines. However, data at the community level remains limited. Our study aimed to estimate incidence and mortality rates and to evaluate risk factors and health-seeking behavior for childhood pneumonia. A household level interview survey was conducted in Biliran Island, the Philippines. Caregivers were interviewed using a semi-structured questionnaire to check if children had symptoms suggesting pneumonia-like episodes from June 2011 to May 2012. Of 3,327 households visited in total, 3,302 (99.2%) agreed to participate, and 5,249 children less than 5 years of age were included in the study. Incidence rates of pneumonia-like episodes, severe pneumonia-like episodes, and pneumonia-associated mortality were 105, 61, and 0.9 per 1,000 person-years, respectively. History of asthma [hazard ratio (HR): 5.85, 95% confidence interval (CI): 4.83–7.08], low socioeconomic status (SES) (HR: 1.11, 95% CI: 1.02–1.20), and long travel time to the healthcare facility estimated by cost distance analysis (HR: 1.32, 95% CI: 1.09–1.61) were significantly associated with the occurrence of pneumonia-like episodes by the Cox proportional hazards model. For severe pneumonia-like episodes, a history of asthma (HR: 8.39, 95% CI: 6.54–10.77) and low SES (HR: 1.30, 95% CI: 1.17–1.45) were significant risk factors. Children who had a long travel time to the hospital were less likely to seek hospital care (Odds ratio: 0.32, 95% CI: 0.19–0.54) when they experienced severe pneumonia-like episodes. Incidence of pediatric pneumonia-like episodes was associated with a history of asthma, SES, and the travel time to healthcare facilities. Travel time was also identified as a strong indicator for health-seeking behavior. Improved access to healthcare facilities is important for early and effective management. Further studies are warranted to understand the causal relationship between asthma and pneumonia.

Impact of indoor air pollution from the use of solid fuels on the incidence of life threatening respiratory illnesses in children in India

Background

India contributes 24% of the global annual child deaths due to acute respiratory infections (ARIs). According to WHO, nearly 50% of the deaths among children due to ARIs is because of indoor air pollution (IAP). There is insufficient evidence on the relationship between IAP from the use of solid fuels and incidence of life threatening respiratory illnesses (LTRI) in children in India.

Methods

Panel data of children born during 2001–02, from the Young Lives Study (YLS) conducted in India during 2002 and 2006–07 was used to estimate the impact of household use of solid fuels for cooking on LTRI in children. Multivariable two-stage random effects logistic regression model was used to estimate the odds of suffering from LTRI among children from households using solid fuels relative to children from households using other fuels (Gas/Electricity/Kerosene).

Results

Bivariate results indicate that the probability of an episode of LTRI was considerably higher among children from households using solid fuels for cooking (18%) than among children from households using other fuels (10%). Moreover, children from households using solid fuels in both the rounds of YLS were more likely to suffer from one or more than one episode of LTRI compared to children from households using solid fuels in only one round. Two-stage random effects logistic regression result shows that children from households using solid fuels were 1.78 (95% CI: 1.05-2.99) times as likely to suffer from LTRI as those from households using other fuels.

Conclusion

The findings of this paper provide conclusive evidence on the harmful effects of the use of solid fuels for cooking on LTRI in India. The Government of India must make people aware about the health risks associated with the use of solid fuels for cooking and strive to promote the use of cleaner fuels.

Changes in childhood pneumonia and infant mortality rates following introduction of the 13-valent pneumococcal conjugate vaccine in Nicaragua

BACKGROUND

In 2010, Nicaragua became the first developing nation to add 13-valent pneumococcal conjugate vaccine (PCV-13) to its national immunization schedule, using a "3+0" dosing schedule. We assessed changes in incidence rates of health facility visits for childhood pneumonia and infant mortality after PCV-13 introduction in the Department of León, Nicaragua.

METHODS

We collected visit diagnoses from all 107 public health facilities in León between 2008 and 2012. We compared rates of pneumonia hospitalizations, ambulatory visits for pneumonia and infant mortality during the prevaccine (2008-2010) and vaccine (2011-2012) periods among different age groups of children using generalized estimating equations, accounting for clustering by municipality. Exposure time was estimated by official municipality population estimates.

RESULTS

The adjusted incidence rate ratio for pneumonia hospitalization in the vaccine versus prevaccine period was 0.67 (0.59-0.75) among infants and 0.74 (0.67-0.81) among 1-year olds. The adjusted incidence rate ratio for ambulatory visits for pneumonia was 0.87 (0.75-1.01) among infants, and 0.84 (0.74, 0.95) among 1-year olds. The adjusted incidence rate ratio for infant mortality was 0.67 (0.57-0.80). We also observed lower rates of health facility visits for pneumonia among age groups (2- to 4-year old and 5- to 14-year old) not eligible to receive PCV-13.

CONCLUSIONS

Within the first 2 years of a PCV-13 immunization program in Nicaragua, we observed lower rates of hospitalizations and ambulatory visits for pneumonia among children of all ages and a lower infant mortality rate. Lower rates of pneumonia among age groups not eligible to receive PCV-13 suggest an indirect effect of the vaccine.

Using mathematical transmission modelling to investigate drivers of respiratory syncytial virus seasonality in children in the Philippines

We used a mathematical transmission model to estimate when ecological drivers of respiratory syncytial virus (RSV) transmissibility would need to act in order to produce the observed seasonality of RSV in the Philippines. We estimated that a seasonal peak in transmissibility would need to occur approximately 51 days prior to the observed peak in RSV cases (range 49 to 67 days). We then compared this estimated seasonal pattern of transmissibility to the seasonal patterns of possible ecological drivers of transmissibility: rainfall, humidity and temperature patterns, nutritional status, and school holidays. The timing of the seasonal patterns of nutritional status and rainfall were both consistent with the estimated seasonal pattern of transmissibility and these are both plausible drivers of the seasonality of RSV in this setting.