Epidemiological and clinical characteristics of malaria patients in Khanh Hoa, Vietnam: the rise of Plasmodium malariae

Authors

Keywords:

malaria; Plasmodium malariae; Vietnam

Abstract

Background: In Vietnam, an unusual rise in P. malariae cases has been observed, accounting for a high proportion of malaria infections in Khanh Hoa province.

Objective: To describe the epidemiological and clinical characteristics of malaria cases caused by P. malariae in Khanh Hoa province, Vietnam, and to assess its recent emergence and distribution pattern.

Methods: A cross-sectional study was conducted in Khanh Vinh region, Khanh Hoa province, Vietnam. Confirmed malaria cases were collected from medical and laboratory records, including demographic, clinical, and parasitological data. Analyses identified trends and patterns of P. malariae infection.

Results: 93.68% of malaria infections were caused by P. malariae and 6.32% by P. vivax. Symptomatic P. malariae accounted for 96.63% of cases, with renal involvement (41.6%), splenomegaly (40.5%), and hepatomegaly (37.1%). The majority of infections occurred in the working-age population (64.2%). The Raglai ethnic group exhibited the highest prevalence (54.7%). The most affected occupation were farmer (72.6%) and students (18.9%). The highest infection rates were observed in Nam Khanh Vinh (36.8%) and Tay Khanh Vinh (37.9%), while P. vivax infections were reported solely in Bac Khanh Vinh and Nam Khanh Vinh.

Conclusions: P. malariae was the predominant species, largely associated with symptomatic infection and frequent renal, splenic, and hepatic involvement. Infections mainly affected the working-age population, with higher prevalence among the Raglai ethnic group, particularly farmers and students, and showed an uneven spatial distribution, with the highest burden in Nam Khanh Vinh and Tay Khanh Vinh.

Downloads

Download data is not yet available.

References

1. WHO. WHO world malaria report 2024: Addressing inequity in the global malaria response [Internet]. Geneva: WHO; 2025. [access: 10/12/2025]. Available from: https://www.who.int/teams/global-malaria-programme/reports/world-malaria-report-2024

2. Venkatesan P. The 2023 WHO World malaria report [Internet]. The Lancet Microbe. 2024 [access: 10/12/2025]; 5(3):e214. Available from: https://www.thelancet.com/journals/lanmic/article/PIIS2666-5247(24)00016-8/fulltext

3. Võ TC, Lê HG, Kang J-M, Naw H, Fan C-K, Trinh NTM, et al. Molecular surveillance of malaria in the Central Highlands, Vietnam [Internet]. Parasitology International. 2021; 83:102374. DOI: 10.1016/j.parint.2021.102374

4. Khanh CV, Lê HG, Võ TC, Quang NX, Nguyen DV, Dung NCT, et al. Unprecedented large outbreak of Plasmodium malariae malaria in Vietnam: epidemiological and clinical perspectives [Internet]. Emerging Microbes & Infections. 2025; 14(1):2432359. DOI: 10.1080/22221751.2024.2432359

5. McKenzie FE, Jeffery GM, Collins WE. Plasmodium malariae blood-stage dynamics [Internet]. The Journal of Parasitology. 2001; 87(3):626–37. DOI: 10.1645/0022-3395(2001)087[0626:PMBSD]2.0.CO;2

6. Dũng NCT, Hoà ĐV, Hào ĐV, Lê BTD, Sơn ND, Thoa NT, et al. Một số đặc điểm dịch tễ, lâm sàng, cận lâm sàng trường hợp bệnh sốt rét hiếm gặp do Plasmodium malariae tại huyện Khánh Vĩnh, tỉnh Khánh Hoà, năm 2023 [Internet]. Tạp chí Y học Dự phòng. 2024;34(5 Phụ bản):30–6. DOI: https://doi.org/10.51403/0868-2836/2024/1856

7. Snounou G, Pinheiro L, Gonçalves A, Fonseca L, Dias F, Brown KN, et al. The importance of sensitive detection of malaria parasites in the human and insect hosts in epidemiological studies, as shown by the analysis of field samples from Guinea Bissau [Internet]. Transactions of the Royal Society of Tropical Medicine and Hygiene. 1993;87(6):649–53. DOI: 10.1016/0035-9203(93)90274-T

8. Rubio JM, Benito A, Roche J, Berzosa PJ, Garcia ML, Mico M, et al. Semi-nested, multiplex polymerase chain reaction for detection of human malaria parasites and evidence of Plasmodium vivax infection in Equatorial Guinea [Internet]. The American Journal of Tropical Medicine and Hygiene. 1999;60(2):183–7. DOI: 10.1016/0035-9203(93)90274-T

9. Walker-Abbey A, Djokam RRT, Eno A, Leke RFG, Titanji VPK, Fogako J, et al. Malaria in pregnant Cameroonian women: the effect of age and gravidity on submicroscopic and mixed-species infections and multiple parasite genotypes [Internet]. The American Journal of Tropical Medicine and Hygiene. 2005 [access: 10/12/2025];72(3):229–35. Available from: https://d1wqtxts1xzle7.cloudfront.net/42287542/229-libre.pdf?1454844658

10. Tam LT, Thinkhamrop K, Suttiprapa S, Clements ACA, Wangdi K, Suwannatrai AT. Bayesian spatio-temporal modelling of environmental, climatic, and socio-economic influences on malaria in Central Vietnam [Internet]. Malaria Journal. 2024 [access: 12/12/2025];23(1):258. Available from: https://link.springer.com/article/10.1186/s12936-024-05074-y

11. Warren M, Collins WE, Jeffery GM, Skinner JC. The seroepidemiology of malaria in Middle America. II. Studies on the Pacific coast of Costa Rica [Internet]. The American Journal of Tropical Medicine and Hygiene. 1975 [access: 12/12/2025];24(5):749–54. Available from: https://europepmc.org/article/med/1190364

12. Hendrickse RG, Adeniyi A. Quartan malarial nephrotic syndrome in children [Internet]. Kidney International. 1979;16(1):64–74. DOI: 10.1038/ki.1979.103

13. Dixon FJ. Comments on immunopathology [Internet]. Military Medicine. 1966; 131(suppl_9):1233–4. DOI: 10.1093/milmed/131.suppl_9.1233

14. Collins WE, Jeffery GM. Plasmodium malariae: parasite and disease [Internet]. Clinical Microbiology Reviews. 2007;20(4):579–92. DOI: 10.1128/cmr.00027-07

Downloads

Published

2026-02-23

How to Cite

1.
Dinh QL, Nguyen NH, Huynh HQ, Truong Pham TG, Nguyen DC, Phu Tran MS, et al. Epidemiological and clinical characteristics of malaria patients in Khanh Hoa, Vietnam: the rise of Plasmodium malariae . Rev. cuba. med. mil [Internet]. 2026 Feb. 23 [cited 2026 Apr. 17];55(1):e026077112. Available from: https://revmedmilitar.sld.cu/index.php/mil/article/view/77112

Issue

Vol. 55 No. 1 (2026): January - March

Section

Research Article

License

Copyright (c) 2026 Quoc Long Dinh, Ngoc Hieu Nguyen, Hong Quang Huynh, Truc Giang Truong Pham, Duc Chinh Nguyen, Manh Sieu Phu Tran, Hue Van Thi Tran

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

Authors who have publications with this Journal accept the following terms:

  • The authors will retain their copyright and guarantee the Journal the right of first publication of their work, which will simultaneously be subject to the Creative Commons Attribution License. The content presented here can be shared, copied and redistributed in any medium or format; Can be adapted, remixed, transformed or created from the material, using the following terms: Attribution (giving appropriate credit to the work, providing a link to the license, and indicating if changes have been made); non-commercial (you cannot use the material for commercial purposes) and share-alike (if you remix, transform or create new material from this work, you can distribute your contribution as long as you use the same license as the original work).
  • The authors may adopt other non-exclusive license agreements for the distribution of the published version of the work (for example: depositing it in an institutional electronic archive or publishing it in a monographic volume) as long as the initial publication in this Journal is indicated.
  • Authors are allowed and recommended to disseminate their work through the Internet (e.g., in institutional electronic archives or on their website) before and during the submission process, which can produce interesting exchanges and increase citations. of the published work.