Imported Malaria in a Malaria-Free Region: A Retrospective Analysis of Epidemiological, Clinical, and Therapeutic Patterns in Tizi-Ouzou, Algeria (2018-2024).

BACKGROUND

OBJECTIVES

Algeria has been certified as malaria-free since 2019 by WHO and last indigenous case was reported in May 2013; however, imported cases remain a concern for possible for reintroduction. This study aimed to describes the epidemiological, clinical, and therapeutic characteristics of imported malaria cases in the Tizi-Ouzou between 2018 and 2024.

METHODS

A retrospective descriptive study was conducted in the Department of Infectious Diseases at the University Hospital of Tizi-Ouzou. Data were collected from hospital registers and archived medical records. Only laboratory-confirmed cases, diagnosed by microscopic examination of Giemsa-stained blood smears, were included. Variables included demographics, travel history, Plasmodium species, incubation period, clinical presentation, disease severity, laboratory findings, treatment, preventive measures, and outcomes.

RESULTS

Among 106 individuals screened, 16 were confirmed as imported malaria (positivity rate 15.1%). Annual cases fluctuated, with a notable increase from 2022 to 2024, reaching 40% positivity in 2024. Most patients were men (87.5%) and adults aged 20-50 yrs (87.5%), mainly Algerian nationals returning from West Africa. Plasmodium falciparum accounted for 87.5% of cases, often with low parasitemia (< 4 % in 68.8%). No patient had used chemoprophylaxis. Fever with chills and sweats was the most common symptom (92.9%). Uncomplicated malaria representes 78.6% of cases, while 21.4% were severe. The main biological abnormalities were anemia (92.8%), thrombocytopenia (42.8%), and hepatic cytolysis (43%). Mefloquine was the most prescribed treatment (71.4%).

INTERPRETATION

CONCLUSION

Imported malaria in Tizi-Ouzou is characterized by P. falciparum predominance, absence of chemoprophylaxis, short post-travel incubation, and travel-linked seasonality. Strengthening pre-travel counseling, improving prophylaxis, uptake, and enhancing clinician awareness are crucial to prevent severe disease and reduce the risk of malaria reintroduction in Algeria.