Resistance to chloroquine, once widely used and highly effective for preventing and treating malaria, has emerged in most parts of the world. Resistance to other antimalaria drugs also is widespread and growing. Drug-resistant strains are as contagious as those that are susceptible to drugs. MDR-TB is more difficult and vastly more expensive to treat, and patients may remain infectious longer due to inadequate treatment. Recent outbreaks of Salmonella food poisoning have occurred in the United States.
Fungal pathogens account for a growing proportion of nosocomial infections.
Fungal diseases such as candidiasis and Pneumocystis carinii pneumonia are common among AIDS patients, and isolated outbreaks of other fungal diseases in people with normal immune systems have occurred recently in the United States. Scientists and clinicians are concerned that the increasing use of antifungal drugs will lead to drug-resistant fungi. In fact, recent studies have documented resistance of Candida species to fluconazole, a drug used widely to treat patients with systemic fungal diseases. Although treatments that combine new protease inhibitor drugs with other anti- HIV medications often effectively suppress HIV production in infected individuals, results from recent clinical studies suggest that many treatment failures occur due to the development of resistance by the virus. They also recognize the critical role that basic research plays in responding to this problem.