Sunshine, rainfall, humidity and child pneumonia in the tropics: time-series analyses

Abstract

3 SummaryFew studies have formally examined the relationship between meteorological factors and the incidence of child pneumonia in the tropics, despite the fact that most child pneumonia deaths occur here. We examined the association between four meteorological exposures (rainy days, sunshine, relative humidity and temperature) and the incidence of clinical pneumonia in young children in the Philippines using three time series methods: correlation of seasonal patterns, distributed lag regression, and case-crossover. Lack of sunshine was most strongly associated with pneumonia in both lagged regression (RR for a 1 hour increase in sunshine per day was 0.67 (95%CI 0.51 to 0.87)) and case-crossover analysis (OR for a 1 hour increase in mean daily sunshine 8 to 14 days earlier was 0.95 (95%CI 0.91 to 1.00)). This association is well known in temperate settings but has not been noted previously in the tropics. Further research to assess causality is needed.4

Clinical Risk Factors for Life-Threatening Lower Respiratory Tract Infections in Children: A Retrospective Study in an Urban City in Malaysia

“…While there was no effect of environmental factors on life-threatening LRTIs, we found a significant association between increased admissions for LRTIs and no rainIt is well known that in cold climates, increased admission for LRTIs, especially of viral aetiology, occur during winter with low temperatures [25].As for the tropics, a study done in the Philippines showed that lack of sunshine was associated with pneumonia, contrary to what we have shown [11]. Another study from Vietnam showed that increase in PM10 was associated with increased admissions for LRTIs in children with a lag effect of 1–6 days [26].…”

“…All the laboratory data were retrieved from the hospital computer data system. Environmental factors may be important in both frequency of admission as well as severity of LRTIs [11], [12]. Hence, data on daily rainfall, daily air pollution index (API) and monthly particulate matter ≤10 µm in aerodynamic diameter (PM10) for Petaling Jaya, Selangor district was obtained from the Malaysian Meteorological Department.…”

Using Mathematical Transmission Modelling to Investigate Drivers of Respiratory Syncytial Virus Seasonality in Children in the Philippines

“…In previous studies in the Philippines, we have found that seasonal variations in child nutrition, as well as in meteorological factors (rainfall, sunshine and relative humidity) were associated with the seasonality of ALRI admissions in children [6], [7]. The lag time between the seasonal peaks in these potential driving factors and the peaks in the yearly ALRI epidemics varied considerably.…”

“…All trial municipalities were within 25 km of Tagbilaran. The number of rainy days per week also serves as a proxy measure of sunshine hours, as these variables are negatively correlated in this tropical setting [7]. The seasonality of infant nutritional status was depicted using a time series of estimated birth weight in the PCV trial participants [6].…”

Temperature variability and childhood pneumonia: an ecological study

“…As climate change proceeds, the possible impact of climate factors on pneumonia transmission has attracted increasing research attention [4,5]. Both high and low temperatures have been reported to be associated with increased pneumonia incidence [6,7].…”