Articles Vol. 67 No. CĐ4-HN Ký sinh trùng-HN Hóa sinh 2026 14/04/2026

THE INCREASED TRANSMISSION OF Plasmodium falciparum MALARIA THREATENS THE MALARIA ELIMINATION GOAL: AN EARLY WARNING FROM KHANH VINH, KHANH HOA PROVINCE, 2025

Nguyen Cong Trung Dung1,2, Dam Van Hao1,2, Nguyen Duy Son1,2, Nguyen Thi Thanh Tram1,2, Bui Thi Ngoc Bich1,2, Trinh Hoang Vy1,2, Cao Thi Khanh Thu1,2, To Ngoc Hai1,2, Do Thi Truc Quynh1,2, Dang Thi Hoai Thu1,2, Ho Van Hoang1,2, Huynh Hong Quang1,2
1 Institute of Malaria-Parasitology-Entomology Quy Nhon, Gia Lai
2 Viện Sốt rét-KST-CT Quy Nhơn, Gia Lai
DOI: 10.52163/yhc.v67iCD4.4691
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Keywords
malaria, Plasmodium falciparum, malaria elimination.
Abstract

Background: After a period of increased malaria from July 2023, transmission was temporarily interrupted in early 2025 in Khanh Vinh. However, malaria returned mainly due to Plasmodium falciparum in May-June 2025, threatening the malaria elimination goal.

Objective: To describe the resurgence and evaluate the changes in transmission dynamics of P. falciparum in Khanh Vinh during the post-control period

Methods: A descriptive study based on retrospective data (2022-2025) and a cross-sectional study in Khanh Dong and Khanh Thuong communes in July 2025, focusing on high-risk groups. Clinical examination, Giemsa-stained blood smear microscopy, and structured interviews were used for assessment.

Results: A total of 408 at-risk individuals were screened; 12 malaria cases (2.94%) were detected. The positivity rate was 4.57% in Khanh Thuong commune and 1.06% in Khanh Dong commune. Of the cases, 91.67% were caused by P. falciparum, 50% were asymptomatic, and 58.33% carried gametocytes; the geometric mean parasite density was 3,606 parasites/µl blood. P. falciparum was observed to cluster in Khanh Thuong, signalling a spatial shift in transmission.

Conclusion: The increase and transmission shift of P. falciparum in Khanh Vinh, especially asymptomatic infections, threaten the malaria elimination goal. Enhanced surveillance and targeted interventions are required.

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