Epidemiology of travel-related malaria in a non-malarious area in Saudi Arabia.

OBJECTIVE The study describes the epidemiology of malaria in the Eastern Province of Saudi Arabia and the species of Plasmodium causing the disease and the associated factors. METHODS This is a retrospective study of the epidemiology of malaria at Saudi Aramco Medical Services Organization in Dhahran, Eastern Province of Saudi Arabia. The study included all patients with malaria from January 1994 to June 2005. We retrieved the cases from the archive epidemiology records on all notifiable diseases. The medical records of patients were reviewed and the following information was collected: age, gender, nationality, year and month of acquisition, travel history and the species causing malaria. RESULTS Over the study period from January 1994 to June 2005, there were 56 cases of imported malaria seen at Saudi Aramco Medical Services Organization. There were 28 males and 28 females with a mean age of 28.2 +/- 19.7 (range, 1-80) years. Saudis constituted 25% of the patients and the remaining (75%) were non-Saudi. Most of the cases (78.7%) were acquired outside Saudi Arabia and 21.3% were acquired in the Kingdom but outside the Eastern Province. The most frequent species were Plasmodium vivax (P. vivax) (54.4%), Plasmodium falciparum (P. falciparum) (43%) and Plasmodium malariae (1.8%). Of the cases acquired within other parts of Saudi Arabia, 71.4% were secondary to P. falciparum. Acquisition of malaria in India P. falciparum constituted 71.4% and in Pakistan 91%. For Sudanese patients, P. falciparum constituted 47% and P. vivax was 53%. Most of the non-Saudi cases were seen in the month of September (19%) whereas 57% of the Saudi cases were seen in February and April. CONCLUSION There were no active cases of malaria transmission within the Eastern province of Saudi Arabia; however, the continued presence of imported malaria into this region may pose a significant health problem especially in the presence of the malaria vector. Thus, effective treatment and vigilance for cases of malaria is needed.