ASSESSMENT OF MALARIA IMMUNE RESPONSE AND ASSOCIATED FACTORS AMONG RESIDENTS IN KHANH VINH DISTRICT, KHANH HOA PROVINCE, 2025

Nguyen Duc Long1, Nguyen Thi Thuy Duong1, Vu Thi Sang1, Dang Thi Tuyet Mai1, Tran Tuyet Mai1, Nguyen Thi Hanh1
1 National Institute of Malaria, Parasitology and Entomology.

Main Article Content

Abstract

Background: In Khanh Vinh district, Khanh Hoa province, the number of malaria cases increased markedly during the period 2021–2024, indicating a persistent risk of malaria outbreaks. In this context, assessment of community-level malaria immune responses is of great importance, as it reflects the extent of exposure to malaria parasites and supports the development of appropriate prevention and control strategies.


Objectives: Determine the proportion of residents with anti-malarial antibodies using the ELISA method and identify associated factors in the study area.


Methods: A cross-sectional descriptive study was conducted in Tay Khanh Vinh and Nam Khanh Vinh communes, Khanh Hoa province, in August 2025. A total of 1,364 residents were enrolled, and serum samples were collected and tested for anti-malarial antibodies using ELISA.


Results: Among 1,364 serum samples tested, 544 were positive for anti-malarial antibodies, corresponding to a seroprevalence of 39.9%. The ELISA positivity rate was similar between males (40.2%) and females (39.7%). The lowest seroprevalence was observed in participants under 15 years of age (7.9%) and increased progressively in those aged 15–29 years (39.4%), 30–44 years (52.7%), and was highest among individuals aged over 45 years (71%). Participants with a history of malaria infection had a significantly higher ELISA positivity rate (68%) compared with those without a history of malaria (35.8%).


Conclusions: The prevalence of antibodies against Plasmodium spp. in the study population remains relatively high (39.9%), highlighting the need for strengthened health communication and malaria prevention and control interventions targeting high-risk groups in the community.

Article Details

References

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