This study aimed to document the method standardisation and assessment of micronutrient and inflammatory markers in women from indigenous tribal communities of Jharkhand using a low-volume, high-throughput assay. This cross-sectional study was done among women of the reproductive age group from Sauria Paharia and Santhal tribal households (HH) in selected villages. Capillary blood samples were collected from the women during a HH survey to estimate ferritin, soluble transferrin receptor, retinol binding protein 4 and inflammatory biomarkers, C-reactive protein (CRP) and α-1-acid glycoprotein (AGP) using a multiplex assay. Vitamin D and Hb were estimated using an LC-MS technique and cyanmethaemoglobin method, respectively. A multiplex Luminex-based method was developed and standardised. The assay was used to estimate biomarkers in samples from 413 women (178 and 235 from Sauria Paharia and Santhal tribes, respectively). Over 51 % of women had raised CRP or AGP levels. Fe status was significantly better in Sauria Paharia compared with the Santhal women. Anaemia prevalence was 72 % among Santhal women. The proportion of women with Fe deficiency increased after adjusting for inflammation. The overall prevalence of vitamin A deficiency and insufficiency was 25 and 34 %, respectively, with similar prevalence in both tribes. All Santhal women had sufficient vitamin D levels, while 25 and 20 % of Sauria Paharia women had insufficient and deficient vitamin D levels, respectively. Our low-volume, high-throughput multiplex assays may provide a feasible approach for assessing nutritional biomarkers in nutritionally vulnerable hard-to-reach communities.

Four species of malaria parasite, Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae and Plasmodium knowlesi infect humans living in the Khanh Phu commune, Khanh Hoa Province, Vietnam. The latter species also infects wild macaque monkeys in this region. In order to understand the transmission dynamics of the three species, we attempted to detect gametocytes of the three species in the blood of infected individuals, and sporozoites in the salivary glands of mosquitoes from the same region. For the detection of gametocyte-specific mRNA, we targeted region 3 of pfg377, pvs25, pmg and pks25 as indicators of the presence of P. falciparum, P. vivax, P. malariae and P. knowlesi gametocytes, respectively. Gametocyte-specific mRNA was present in 37, 61, 0 and 47% of people infected with P. falciparum (n = 95), P. vivax (n = 69), P. malariae (n = 6) or P. knowlesi (n = 32), respectively. We found that 70% of mosquitoes that had P. knowlesi in their salivary glands also carried human malaria parasites, suggesting that mosquitoes are infected with P. knowlesi from human infections.