Lyme Disease First recognized as an infectious disease in 1975, Lyme disease is the most common tick-borne infection in the United States. Analyses of the bacterium's various proteins led to the development of rapid and sensitive blood tests for the disease. Scientists are examining whether these antigens might also be potential vaccine candidates. Influenza In the United States, approximately 25 percent of the population has an influenza-associated illness annually, leading to an average of 20,000 to 40,000 excess deaths per year. Many people might not think of flu as an emerging disease, but influenza viruses change from year to year and virulent strains have emerged throughout history to cause worldwide, catastrophic pandemics.
Many scientists believe the next pandemic is long overdue.
Children experience the highest incidence of influenza disease, two to 10 times that seen in adults, and are a common source of its spread. As these figures indicate, the AIDS epidemic still rages out of control, particularly in sub-Saharan Africa and in Asia. However, recent reports of significant progress in clinical and basic research on HIV disease have fostered cautious optimism within the AIDS research community. The arrival of the protease inhibitor drugs, which were shown to reduce the amount of HIV in the blood of many infected persons to undetectable levels when used in combination with other AIDS drugs, has dramatically altered the epidemic in the United States. Approximately 31,130 deaths attributable to HIV infection occurred in the United States in 1996.