Abstracts of the 9th International Conference on Plasmodium vivax Research (ICPvR) 2025

Background: Rapid diagnostic tests (RDTs) are widely used in malaria control programs for their ease of use and ability to provide quick results.However, their sensitivity may be limited, particularly in detecting low-level or asymptomatic infections.Examination of the peripheral smears for detection of malaria is gold standard but expertise of microscopist plays important role, and may be responsible for missing presence of malaria parasite in peripheral smear.Asymptomatic carriers, though not exhibiting symptoms may be acting as reservoirs within the community and can still contribute to malaria transmission.Materials and methods: In this study, we aimed to detect Plasmodium species in asymptomatic individuals who tested negative for malaria using a RDT and examination of peripheral smear.A total of 131 RDTnegative samples were collected from asymptomatic individuals from selected villages of Bikaner district.Each sample was carefully processed to ensure the quality of DNA for downstream analysis.We employed real-time Polymerase Chain Reaction (PCR) to enhance the detection sensitivity for low-level infections.DNA was extracted from each sample using a standardized extraction protocol.Following extraction, real-time PCR targeting Plasmodium species specific genes was performed to identify the presence of Plasmodium DNA in each sample.The PCR reactions were conducted in triplicate to ensure accuracy, and appropriate positive and negative controls were included in each run. Results:In this study, we analysed 131 asymptomatic, RDT and peripheral smear negative samples to investigate the presence of Plasmodium species.Our objective was to determine if Plasmodium species could be detected in asymptomatic individuals despite negative RDT and peripheral smear examination results.Out of the 131 samples, three were found to be positive for Plasmodium vivax (P.vivax) and negative for Plasmodium falciparum (P.falciparum).This finding suggests that asymptomatic individuals may harbour low-level infections that are not detected by standard diagnostic test, highlighting a potential gap in malaria detection and the importance of further research in surveillance of asymptomatic malaria. Conclusion:Our study revealed that, among 131 asymptomatic and RDT/peripheral smear negative, three samples tested positive for Plasmodium vivax.This indicates that asymptomatic individuals can carry low density malaria infections undetected by routine testing, pausing potential challenges to malaria control and elimination efforts.These findings underscore the need for more sensitive diagnostic tools and reinforce the importance of monitoring asymptomatic carriers to prevent further transmission.