The course of infection with HIV takes place over a number of years. After being exposed to HIV, a person may or may not notice mild, flu-like symptoms for a few weeks, during which time the virus is present in the blood and body fluids and may be easily transmitted to others by sex or other risky behaviors.

 

The body’s immune system responds as it would to any viral infection, producing specific antibodies that eliminate most of the circulating viruses. The infection then enters a latent period, with the viruses mostly hidden in the DNA of the T4 cells, although a constant battle is taking place between the virus and the immune system. It is clear that in the struggle between microbes’ ability to evolve new variations and human ingenuity in devising new defenses against them, the microbes are gaining.

 

In a special issue of Science magazine devoted to emerging infections, a CDC scientist says that a “post-antimicrobial era may be rapidly approaching,” when effective antibiotics will no longer be available to treat bacterial infections. If so, that era will force public health professionals back to more emphasis on prevention of disease transmission with classical public health measures such as surveillance, immunization, sanitation, and infection control procedures.