Spatio-Temporal Analysis of Dengue and Weather Variables in Yogyakarta

BACKGROUND: Dengue Hemorrhagic Fever (DHF) is one of the main public health issues in Indonesia, and is endemic in all provinces. The annual incidence of DHF has been fluctuated in Yogyakarta. This study aimed to examine the pattern of the relationship among weather variables on the incidence of dengue in the city of Yogyakarta for 5 years (2010-2014). SUBJECT AND METHODS: This was an ecological study with spatio-temporal approach. The study population was the incidence of dengue for the period 2010-2014 in Yogyakarta city. The independent variables in this study were rainfall, temperature, relative humidity, and wind velocity. The dependent variable was the incidence of DHF. The data was analyzed using graphic/time-trend and spatial statistical analysis. Rainfall in theory increases mosquito breeding place. In this study, however, rainfall was not included in fitting the regression analysis model. RESULTS: There was a relationship among weather variable with dengue incidence, both in graphs/time-trend and spatial statistic analyses. In the graph/time-trend and spatial analysis, there was a relationship between dengue outbreaks in 2010 and 2013 in rainfall fluctuations and temperature. Two regressions models were used, i.e. Poisson Regression and Negative Binomial Regression. The smallest Akaike‟s Information Criterion (AIC) and Bayesian Information Criterion (BIC) values were used to indicate model fit with respect to the contribution of weather variables on dengue incidence. The incidence of dengue at a lag of one month, temperature of the same month, temperature at the lag of two months, relative humidity of the same month, relative humidity at the lag of three months, and wind velocity at the lag of two months, were predictors for dengue incidence. CONCLUSIONS: The pattern of dengue incidence following climate fluctuation, rainfall lag of two months, temperature lag of three months, humidity in lag of one month, had positive association with increased incidence of dengue. Wind velocity was inversely associated with dengue incidence of the same month. The policy implication of the study is that the Health Office of Yogyakarta city should consider climatological data in surveillance and planning dengue prevention program. Keywords: dengue hemorrhagic fever, vector-borne disease, climate, spatio-temporal analysi

Phylogenetic and immunoinformatic analysis of VP4, VP7, and NSP4 genes of rotavirus strains circulating in children with acute gastroenteritis in Indonesia

Rotavirus is a major cause of diarrhea in Indonesian children. However, rotavirus vaccines have not been introduced in the national immunization program of Indonesia. Understanding the genetic diversity and conserved antigenic regions of circulating strains are therefore essential to assess the potential efficacy of rotavirus vaccines. We collected fecal samples from hospitalized children less than 5 years of age with acute diarrhea. Rotavirus genotyping was performed by reverse transcriptase polymerase chain reaction, followed by sequencing of the VP4, VP7, and NSP4 genes of representative strains. Phylogenetic analysis was performed to investigate their relationship with globally circulating strains. Conservational analysis, immunoinformatics, and epitope mapping in comparison to vaccine strains were also performed. The sequence analyses showed that differences of multiple amino acid residues existed between the VP4, VP7, and NSP4 antigenic regions of the vaccine strains and the Indonesian isolates. However, many predicted conserved epitopes with higher antigenicity were observed in the vaccine and Indonesian strains, conferring the importance of these epitopes. The identified epitopes showed a higher potential of rotavirus vaccine to be employed in Indonesia. It could also be helpful to inform the design of a peptide vaccine based on the conserved regions and epitopes in the viral proteins

Phylogenetic and immunoinformatic analysis of VP4, VP7, and NSP4 genes of rotavirus strains circulating in children with acute gastroenteritis in Indonesia

Rotavirus is a major cause of diarrhea in Indonesian children. However, rotavirus vaccines have not been introduced in the national immunization program of Indonesia. Understanding the genetic diversity and conserved antigenic regions of circulating strains are therefore essential to assess the potential efficacy of rotavirus vaccines. We collected fecal samples from hospitalized children less than 5 years of age with acute diarrhea. Rotavirus genotyping was performed by reverse transcriptase polymerase chain reaction, followed by sequencing of the VP4, VP7, and NSP4 genes of representative strains. Phylogenetic analysis was performed to investigate their relationship with globally circulating strains. Conservational analysis, immunoinformatics, and epitope mapping in comparison to vaccine strains were also performed. The sequence analyses showed that differences of multiple amino acid residues existed between the VP4, VP7, and NSP4 antigenic regions of the vaccine strains and the Indonesian isolates. However, many predicted conserved epitopes with higher antigenicity were observed in the vaccine and Indonesian strains, conferring the importance of these epitopes. The identified epitopes showed a higher potential of rotavirus vaccine to be employed in Indonesia. It could also be helpful to inform the design of a peptide vaccine based on the conserved regions and epitopes in the viral proteins

The prevalence and determinants of vitamin D deficiency in Indonesian infants at birth and six months of age

BACKGROUND: Vitamin D deficiency in infants has been associated with an increased risk of a number of diseases but there are limited data on the prevalence and determinants of vitamin D deficiency from tropical settings with high infant morbidity and mortality. OBJECTIVE: To determine the prevalence and determinants of vitamin D deficiency in infants at birth and at six months of age in Yogyakarta province, Indonesia. DESIGN: Serum vitamin D of eligible infants was measured in cord blood at birth and at six months of age. Factors associated with vitamin D deficiency (serum 25-hydroxyvitamin D <50 nmol/L) were collected prospectively monthly from birth and concentrations measured by liquid chromatography-tandem mass spectrometry. Independent risk factors were identified by multiple logistic regression. RESULTS: Between December 2015 to December 2017, 350 maternal-newborn participants were recruited and followed up. Vitamin D deficiency was detected in 90% (308/344) of cord blood samples and 13% (33/255) of venous blood samples at six months. Longer time outdoors (≥2 hours per day) and maternal multivitamin intake containing vitamin D during pregnancy were protective against vitamin D deficiency at birth (AOR: 0.10, 95% CI: 0.01-0.90 and AOR: 0.21, 95% CI: 0.06-0.68, respectively). Risk factors for vitamin D deficiency at six months included lower cumulative skin-sun exposure score (AOR: 1.12, 95% CI: 1.04-1.20), severe vitamin D deficiency at birth (AOR: 7.73, 95% CI: 1.20-49.60) and exclusive breastfeeding (AOR: 2.64, 95% CI: 1.07-6.49) until six months. Among exclusively breast fed (EBF) infants, a higher skin-sun exposure score was associated with reduced vitamin D deficiency risk. CONCLUSION: In equatorial regions, the role of 'safe' morning sun exposure in infants and mothers in populations with medium to dark brown skin pigmentation and effective interventions to prevent vitamin D deficiency in newborns and EBF infants, need further consideration and evaluation

Nutritional status, exclusive breastfeeding and management of acute respiratory illness and diarrhea in the first 6 months of life in infants from two regions of Indonesia

Abstract Background Infant morbidity and mortality rates remain high in Indonesia, with acute respiratory illnesses (ARI) and diarrhea the leading two health problems in children under 5 years. We aimed to describe the nutritional status, feeding practice and case management of ARI and diarrhea of infants from two regions of Indonesia during the first 6 months of life. Methods This study was an observational study conducted in parallel to an immunogenicity and efficacy trial of an oral rotavirus vaccine (RV3-BB) in the Klaten and Yogyakarta regions, Indonesia. Mothers were interviewed at 3 time points: within the first 6 days of their infant’s life, and at 8–10 and 22–24 weeks of age. Questions asked included pregnancy history, infant nutritional status, feeding status and health of infants within up to 2 weeks prior to the assessment. Results Between February 2013 and January 2014, 233 mother-infant pairs were recruited. 60% (136/223) of infants were exclusively breastfed (EBF) until 6 months of age with the strongest support for EBF reported by mothers themselves 70% (101/223) and 25% (36/223) from their partners. At 6 months, 6% (14/223) of infants were underweight and severely underweight; 4% (8/ 223) wasted and severely wasted; and 12% (28/223) were stunted and severely stunted. Non-recommended medication use was high, with 54% (21/39) of infants with reported cough within 2 weeks of an assessment receiving cough medication, 70% (27 /39) an antihistamine, 26% (10/39) a mucolytic and 15% (6 /39) an oral bronchodilator. At age 22–24 week, infants with reported diarrhea within 2 weeks of an assessment had low use of oral rehydration solutions (ORS) (3/21;14%) and zinc therapy (2/ 21;10%). Conclusion In this unique observational study, breastfeeding rates of 60% at 6 months were below the Indonesian national target of >75%. Adherence to WHO guidelines for management of ARI and diarrhea was poor, with high use of non-recommended cough medications and oral bronchodilators in the first 6 months of life and low use of ORS and zinc therapy. Ongoing education of primary health care workers and parents regarding management of common illness is needed in Indonesia