An epidemiological investigation of an border-imported case with Plasmodium vivax malaria

Abstract@#On March 12, 2022, a case with Plasmodium vivax malaria was reported in the First Hospital of Jiaxing City. The case sought healthcare services due to persist, sharp distending pain of the brain and fever on February 25, 2022, and the symptoms showed no improvements following symptomatic treatment. Microscopy identified malaria parasites on March 12, and the case was definitively diagnosed as P. vivax malaria on March 13. The case was discharged from hospital on March 16 and relapsed on June 15. The case was a veteran from the China-Myanmar border, where malaria is highly prevalent, and had no history of travel after returning to Jiaxing City on October 2021. Based on epidemiological history and laboratory tests, the case was diagnosed as a cross-border mosquito-borne imported case of P. vivax malaria. The case was given treatment with mosquito vector isolation, and the case's family members, neighbors and colleagues were all tested negative for malaria parasites. There was no Anopheles sinensis detected in the case' residence; however, Anopheles was detected in the neighboring areas, indicating a risk of re-establishment. Returners from high-risk regions including borders and labor exporters are recommended to be included in malaria surveillance, and the sensitivity of malaria surveillance requires to be maintained and the diagnostic and treatment capability of malaria requires to be improved in medical institutions.