discussion on the health effects of antimalarial drugs can be found in the section on ophthalmologic complications below.

Coinfection with Plasmodium Spp. and Human Immunodeficiency Virus

There is clear evidence that HIV infection, particularly with lower CD4+ cell counts, is associated with an increased risk of malaria, higher levels of parasitemia, and higher mortality (Butcher 2005). Nevertheless, malaria and HIV coinfection in a soldier deployed to southwest or south-central Asia would be highly improbable, given the low rates of HIV in southwest and south-central Asia, segregation of US military troops from civilian populations, periodic HIV screening of troops and removal of soldiers testing HIV-positive from overseas service, and low malaria transmission rates.

Long-Term Adverse Health Outcomes of Infection with Plasmodium Spp.

Infection by Plasmodium potentially has long-term repercussions for human health. Long-term adverse health outcomes of infection can be manifested in neurologic, neuropsychiatric, ophthalmologic, hematologic, or renal disease. In addition, malaria itself can present after a latency of months to years or may break out anew because of undertreatment.

The epidemiology of malaria in Afghanistan and Iraq suggests that P. vivax is the principal threat to US troops deployed to OEF and OIF. P. falciparum was not known to circulate in Iraq in 1991-2005, and, although reported in Afghanistan, it is far less prevalent than P. vivax. Although P. falciparum predominates in Saudi Arabia, only seven cases of malaria were reported in US troops during the Persian Gulf War, as described in Chapter 4. P. ovale and P. malariae are rare in southwest and south-central Asia.

Hematologic Complications

Splenic rupture is a well-described complication of malaria, particularly that caused by P. vivax. It can occur weeks to months after the acute infection. Hyperreactive malaria syndrome or tropical splenomegaly can be noted months or years after malarial infection (Metha et al. 1996).

Anemia is a principal complication of malaria. It is expected as an acute event, but it may be detected months or even years after the infection. Only in cases of fulminant falciparum malaria is anemia so severe as to be debilitating or life-threatening. Repeated hemolysis, presumably due to subcurative treatments, is reported as a chronic complication (Metha et al. 1996).

The committee concludes that there is sufficient evidence of a causal relationship between malaria infection and hematologic manifestations weeks or months later, particularly splenic rupture after vivax malaria and anemia after falciparum malaria.

Ophthalmologic Complications

A number of case reports describe the complication of retinal hemorrhage associated with severe cerebral malaria and following vivax malaria. Permanent visual loss may result from this complication (Choi et al. 2004). The capillary permeability associated most notably with falciparum malaria has been associated with retinal hemorrhage and edema, with occasional serious visual impairment, in adults and children (Beare et al. 2003; Hidayat et al. 1993; Kochar



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement