Imported malaria in children: a comparative study between recent immigrants and immigrant travelers (VFRs).

Background: In Europe, imported malarial cases occur in returning travelers and immigrants mostly from African countries. There have been an increasing number of cases in the past years in Spain.

Methods: An analysis of all cases of malaria who attended at the Hospital of Mostoles in the Southwest of Madrid from 1995 to 2007 was performed. Clinical, epidemiological, laboratory, and parasitological findings were analyzed and compared between immigrants coming from endemic countries (recent immigrants) and children who traveled to endemic areas to visit friends and relatives (VFRs).

Results: Sixty cases of imported malaria were detected. Most of the cases (59 of 60) were acquired in sub-Saharan Africa. The most common species was Plasmodium falciparum (43 of 60). Microscopic examination was positive in 95%, and the polymerase chain reaction (PCR) for Plasmodium achieved additional diagnosis in seven cases. Fourteen cases were VFRs; none of them used appropriate malaria chemoprophylaxis. Fever and thrombocytopenia were significantly more common among VFRs. They also had significantly higher parasite density. Twelve cases were asymptomatic at the time of diagnosis; all of them were recent immigrants.

Conclusions: VFRs account for a significant number of childhood malarial cases. These patients had not taken malaria chemoprophylaxis and malarial cases were more severe. VFR children are a high-risk group, and pretravel advice should underline the risk for malaria. Recent immigrants can be asymptomatic and parasitemias are lower. Therefore, a high index of suspicion is necessary, and PCR for Plasmodium should be performed in case of negative thick smears.