Host susceptibility genes of asymptomatic malaria from South Central Timor, Eastern Indonesia.

Host genetic factors, such as the genes for various cytokines and adhesion molecules, play a significant role in determining susceptibility to malaria infection. Polymorphisms in host genes have been correlated with malaria infection in both African and Asian regions. The purpose of this study was to investigate the association between both cytokine and adhesion molecule genotypes with susceptibility to malaria infection in humans. Ten cytokine polymorphism loci (IL4 + 33, IL4-590, IL6-174, IL10-1082, IL10-1035, IL12p40, TNF-238, TNF-308, TNF-1031, and TNF-ß) and three adhesion molecule polymorphism loci (CD36 exon 10, ICAM-1 Kilifi, and ICAM-1 exon 6) were genotyped using PCR-RFLP analysis. We conducted this study on 178 asymptomatic malaria subjects and 122 uninfected subjects. Results showed that certain CD36 exon 10 and IL10-3575 polymorphisms were associated with asymptomatic infection. The heterozygous (GT) and homozygous (GG) genotypes for CD36 exon 10 are associated with an increased risk of malaria infection. On the other hand, the homozygous genotype (AA) for IL10-3575 reduced the risk of asymptomatic malaria infection. No significant differences were found for the other polymorphisms studied. We also found that a polymorphism in CD36 exon 10 was strongly associated with asymptomatic malaria caused specifically by Plasmodium vivax. These findings suggest that the G allele of CD36 exon 10 is associated with an increased risk of asymptomatic malaria infection. On the other hand, the genotype AA for IL10-3575 was associated with a reduced risk of malaria infection.

Urban-rural distinction of potential determinants for prediabetes in Indonesian population aged ≥15 years: a cross-sectional analysis of Indonesian Basic Health Research 2018 among normoglycemic and prediabetic individuals.

BACKGROUND: Based on Basic Health Research (RISKESDAS) conducted by Ministry of Health, Indonesia, prediabetes prevalence tends to increase from 2007 until 2018. The numbers are relatively higher in rural than those in urban area despite of small discrepancies between the two (~ 2-4%). The purpose of this study was to identify urban-rural differences in potential determinants for prediabetes in Indonesia. METHODS: This analysis used secondary data collected from nationwide Health Survey in 2018. Respondents were aged ≥15 years who met inclusion criteria of analysis with no history of diabetes mellitus. Prediabetes criteria followed American Diabetes Association 2019. Multiple logistic regression was also employed to assess the transition probability of potential determinants for prediabetes in urban and rural Indonesia. RESULTS: Up to 44.8% of rural respondents were prediabetics versus their urban counterparts at 34.9%, yet non-response bias was observed in the two. Young adults aged 30 years were already at risk of prediabetes. Urban-rural distinction for marital status and triglyceride level was observed while other determinants tended to overlap across residence. Several modifiable factors might contribute differently in both population with careful interpretation. CONCLUSIONS: The minimum age limit for early prediabetes screening may start from 30 years old in Indonesia. Urban-rural distinction for marital status and triglyceride level was observed, yet non-response bias between the two groups could not be excluded. A proper model for early prediabetes screening need to be developed from a cohort study with adequate sample size.

The effectiveness of hepatitis B vaccine in toddlers based on the five-year period national basic health research (Riskesdas 2007, 2013 and 2018) in Indonesia.

Background: Hepatitis B is a viral infection that has a high prevalence in Indonesia. The Ministry of Health of Indonesia has conducted a national vaccination program for hepatitis B. In order to evaluate the success of the hepatitis B vaccination in Indonesia, a community study based on basic health research (Riskesdas) was performed nationwide since 2007 for five year period in 2007, 2013, and 2018. Methods: Further statistical analysis was performed specifically for the children under 59 months old (toddlers) immunized in both urban and rural areas in 2007, 2013, and 2018 based on certain characteristics by examining antibodies against HBsAg (anti-HBs), IgG antibodies against the core antigen (HBcAb), surface antigen (HBsAg) of hepatitis B virus (HBV). The data obtained from the data management laboratory of Ministry of Health, Indonesia, was analyzed with Bivariate analysis with continuity correction chi-square or Pearson chi-square using Stata software version 16. Results: This study showed an increase in hepatitis B coverage of complete immunization (30% in 2007, 60.3% in 2013, and 57% in 2018), which was also influenced by mothers' level of education (Pearson chi-square , p ¡ 0.05) and access to health service points within 30 minutes (OR = 1.3-2.8, p ¡ 0.05). The trend of the percentage of immune status (anti-HBs) was increased (41.8% in 2007; 56.1% in 2013; and 79.1% in 2018). The higher anti-HBs was found in complete hepatitis B immunization status (OR = 1.5-2, p ¡ 0.05) and in good nutritional status (p ¡ 0.05). However, the anti-HBs was found decreased with increasing age (p ¡ 0.05). The trend of positive HBcAb (exposure to HBV infection) showed a decrease gradually of almost ten times from 2007 (8.6%-13.5%) compared to 2013 (2.6%-11.1%) and 2018 (1.1%-2%). Urban areas were at higher risk of hepatitis B exposure (OR = 1.4-2.2) than rural areas (OR = 0.37-0.80). The HBsAg data were only available in 2013 and 2018. Riskesdas data analysis showed the prevalence of hepatitis B (HBsAg) was lower in complete immunization status than that in incomplete one (p ¡ 0.05), but with an increase from 3.9% (2013) to 9.3% (2018), possibly due to inappropriate implementation of birth dose immunization or a vaccine-escape mutant from the HBV variants. Conclusions: The effectiveness of hepatitis B vaccine obtained from the three Riskesdas periods in Indonesia showed an improvement, with an increase in immune status, reduced exposure to HBV and a lower prevalence of hepatitis B in children with complete vaccination. However, there is still an increase in hepatitis B infection, especially in urban areas. Therefore, a long-term evaluation of immunization coverage especially ensuring that the initial dose of immunization was given within the first 24 h of birth, HBsAg and HBcAb, nutritional status, genomic surveillance of HBV, and other aspects of program quality evaluation are needed to ensure that elimination efforts have been implemented properly.

Prevalence of Glucose 6-Phosphate Dehydrogenase Variants in Malaria-Endemic Areas of South Central Timor, Eastern Indonesia.

Primaquine is an effective anti-hypnozoite drug for Plasmodium vivax and Plasmodium ovale. However, it can trigger erythrocyte hemolysis in people with glucose 6-phosphate dehydrogenase (G6PD) deficiency. In a previous report from South Central Timor (SCT), Indonesia, we described the prevalence of Vanua Lava, Chatham, and Viangchan variants; in this study, other G6PD variants (Kaiping, Coimbra, Gaohe, Canton, and Mahidol) were subsequently analyzed. For clarity, all of these results are described together. The 381 DNA samples from the previous study during 2013-2014 were analyzed for G6PD variants by using PCR-restriction fragment length polymorphism (RFLP). The prevalence of G6PD deficiency in SCT was 6.3% (24/381 cases), including 4.2% (16/381 cases), 0.5% (2/381 cases), and 1.6% (6/381 cases) for Coimbra, Kaiping, and Vanua Lava variants, respectively. No other variants were found in this population. A significant association was found between ethnicity and the distribution of G6PD Kaiping in female subjects. A positive association was shown between G6PD activity and heterozygous females carrying Coimbra genotype, hemizygous males carrying Vanua Lava, Plasmodium falciparum infection in female subjects, and P. vivax infection in male subjects. Further molecular analysis of heterozygous females, particularly in malaria-endemic areas, is needed for mapping distribution of G6PD deficiency status in Indonesia.

High deformability of Plasmodium vivax-infected red blood cells under microfluidic conditions.

Maturation of Plasmodium falciparum decreases the deformability of infected red blood cells (RBCs), increasing their clearance as they attempt to pass through endothelial slits of the splenic sinus. Previous studies of Plasmodium vivax-infected RBCs led to opposite conclusions with respect to cellular deformability. To resolve this controversy, P. vivax-infected RBCs were passed through a 2-microm microfluidic channel. In contrast to P. falciparum-infected RBCs, mature P. vivax-infected RBCs readily became deformed through 2-microm constrictions. After this extreme deformation, 67% of P. vivax-infected RBCs recovered a normal appearance; however, 15% of uninfected RBCs were destroyed. Results suggest mechanisms for both avoidance of splenic clearance and anemia in vivax malaria.