Apparent relapse of imported Plasmodium ovale malaria in a pregnant woman

A 27 week pregnant woman who had lived in Bangkok, Thailand, for 18 months presented to her obstetrician with a 1-week history of intermittent fever and malaise. Medical history was significant for multiple episodes of malaria during her 10 years of employment in sub-Saharan Africa before her relocation to Thailand. The initial malaria smear was negative. She returned a week later with no resolution of her symptoms, at which time she was found to have Plasmodium ovale by microscopy and polymerase chain reaction. She had an excellent response to chloroquine, which she continued weekly until 36 weeks of gestation. She delivered a healthy term infant and received radical cure with primaquine after cessation of breastfeeding. This case shows challenging issues in detection and management of imported P. ovale malaria.