Despite the slowly decreasing global malaria burden, US malaria case hit a 40-year high in 2011, part of a rise that likely reflects growth in international travel and lapses in precautions among overseas travelers, the Centers for Disease Control and Prevention (CDC) said in a report today.
The CDC said 1,925 malaria cases were reported in 2011, up 14% from the previous year, and up 48% since 2008. Five of the patients in 2011—the most recent year for which data are available—died from malaria or its complications. The report appeared in Morbidity and Mortality Weekly Report (MMWR).
All but five of the cases were acquired overseas. One was lab acquired, one was transfusion related, two were congenital, and one was cryptic.
Malaria, caused by a parasite transmitted by infected female Anopheles mosquitoes, sickens about 219 million people around the world each year and is linked to about 660,000 deaths. Malaria symptoms can vary, but most patients have fever, often with headache and flulike symptoms. When untreated, the disease can lead to coma, kidney failure, respiratory failure, and death.
A similar rise in imported malaria cases has been seen in the United Kingdom, the CDC said. It warned that imported malaria can reintroduce the disease into areas, such as the United States, where the disease isn't endemic. And the agency added that US environmental conditions could support the life cycle of the parasite and its mosquito carrier.
Nearly two thirds of the patients were infected in West African countries, but for the first time India was the country from which most cases were imported, the CDC said. Seasonal peaks were noted in January and August, which are peak times to African travel destinations for winter and summer holidays, according to the MMWR report.