Malaria Infection in Thapangthong District, Savannakhet Province, Lao PDR, 2025: Bed Net Use and Forest Visit
DOI:
https://doi.org/10.59096/osir.v18i4.278045Keywords:
malaria, Lao PDR, long-lasting insecticide-treated net (LLIN), forest-related malariaAbstract
On 19 Mar 2025, four Plasmodium vivax cases were reported in Thapangthong District, Savannakhet Province—an area previously considered malaria-free in Lao People’s Democratic Republic (Lao PDR). The investigation was conducted from
20–28 Apr 2025. We aimed to confirm the outbreak, describe characteristics of the cases, identify associated factors, and recommend containment measures. We reviewed District Health Information Software Version 2 (DHIS2)—a national surveillance system for public facilities of Lao PDR. An active case finding was conducted in three villages in Thapangthong District. Univariable and multivariable logistic regression models were performed. Qualitative phone interviews with key stakeholders were conducted. From January to April 2025, eight confirmed malaria cases were detected based on DHIS2. Of the 294 screened individuals, 20 P. vivax cases (12 suspected and 8 confirmed) were identified. Multivariable analysis showed that prior malaria infection and recent travel history to endemic areas were significantly associated with increased odds of infection. Use of long-lasting insecticide-treated nets (LLIN) was associated with a non-significant but lower odds of infection. All participants with a history of forest visits were cases. The interviews revealed that a malaria control barrier included low usage of LLIN by the villagers. Rapid interventions, including a mass drug campaign, were implemented. As of 31 May 2025, no new cases had been detected. To advance malaria elimination, we recommend strengthening campaigns that promote LLIN usage, particularly among forest-goers, providing refresher courses on malaria-related knowledge for villagers and health volunteers, and maintaining active vigilance for new cases.
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