Dying of Malaria in the United States

Abstract & Commentary

Synopsis: Nearly 1 in every 100 US travelers with malaria reported to the National Malaria Surveillance System died of the infection. The majority of deaths were preventable.

Source: Newman RD, et al. Malaria-Related Deaths Among U.S. Travelers, 1963-2001. Ann Intern Med. 2004;141: 547-555.

All 165 cases of malaria-related deaths in the United States reported to the National Malaria Surveillance System from 1963 to 2001 were reviewed. Two-thirds occurred in US travelers, and 92.7% of deaths were due to Plasmodium falciparum infection. From 1985 to 2001, the case fatality rate was 1.3% for P. falciparum, 0.06% for P. vivax, 0.3% for P. malariae, and 0.3% for P. ovale. Most cases were acquired in Africa, with Kenya, Nigeria, and Liberia accounting for 40.6% of fatal cases. The median duration of stay was 22 days, ranging from < 1 day to 23 years.

Of the 123 who died from 1985 to 2001, only 34 individuals were known to have taken chemoprophylaxis and, of these, only 20 (58.8%) took an appropriate agent and 6 (30%) of these were non-adherent. As a consequence, only 7 of 123 (5.7%) were known to take appropriate chemoprophylaxis and to adhere to their regimen!

The median interval from return to symptom onset was 5 days. Of the 90 patients for whom data was available, only one-third received a diagnosis of malaria on the day of their initial contact with medical care, so that the median time to diagnosis was 4 days (range, 1 to 17 days). Of the 109 who received medical attention before dying, 6 had a delay in initiation of antimalarial therapy of 12 to 24 hours and 18 (16.5%) never received any. Of 90 recipients of antimalarials for whom data was available, 9 (10%) were given inappropriate therapy.

Of the 195 (85.4%) deaths considered preventable, the patient’s own decisions, such as non-adherence to prophylaxis and delay in seeking care, contributed to the outcome. In two-thirds, however, medical errors, both pre- and post-travel, may have contributed to the fatal outcome.

Comment by Stan Deresinski, MD, FACP

Several months ago, I saw a young woman recently returned from visiting family in India. She had had a febrile illness for 11 days. She had been to an urgent care center twice and, on one occasion, went to a local hospital emergency department at 3 AM with a temperature of 39.9°. She had not taken malaria prophylaxis in India and was concerned about malaria, a concern which she told me she reported to health care workers during these contacts. Despite all this, no malaria smear was obtained and no diagnosis made! She, fortunately, turned out to be infected with P. vivax (as well as having dengue!), for if it had been P. falciparum, she likely would have been added to the national database of malaria fatalities.

Although, as indicated by the above analysis, patients may contribute to their adverse outcomes, many of the errors listed by health care workers in this report are inexcusable. A key element is to always maintain a level of suspicion, asking about travel in all febrile patients (and to listen to the patient when they think they may have malaria). Malaria smears should be performed and examined immediately. If negative, smears should be repeated twice over the next 24 hours (see Table). Therapy should be initiated immediately. In cases in which plasmodia are detected and P. falciparum cannot be excluded in a patient traveling from an area with chloroquine resistance (ie, most malarious regions of the world), treatment should be initiated with drugs active against chloroquine resistant P. falciparum. For patients who require parenteral therapy for P. falciparum infection, the unavailability of quinine sulfate suitable for intravenous administration, together with the removal of quinidine from many hospital formularies, led to unacceptable delays in initiation of therapy in some of the cases reviewed in this report. Until (and if) artemesinin derivatives become available in the United States, hospital pharmacies should maintain a small supply of quinidine for such emergency use—P. falciparum infections in non-immune hosts can be fatal within hours of presentation if untreated.

Nearly 1 in 100 US travelers with malaria diagnosed and reported to the National Malaria Surveillance System died—not a good record.

Stan Deresinski, MD, FACP, Clinical Professor of Medicine, Stanford; Associate Chief of Infectious Diseases, Santa Clara Valley Medical Center, is Editor for Infectious Disease Alert.