Suppose a person is infected with HIV, but he looks like a healthy, normal person. Are there any physical symptoms or signs we can detect to know that this person is HIV-infected?

M.

HIV, the human immunodeficiency virus, is the virus that causes AIDS, the acquired immune deficiency syndrome. After infection, it takes several years to develop any sign of the disease. The signs of HIV infection usually are due to secondary or so-called "opportunistic" infections. These include various forms of pneumonia, mouth infections, skin infections and meningitis (infection of the tissue covering the brain and spinal cord). In addition to opportunistic infections, tumors such as Kaposi's sarcoma and lymphoma can be manifestations of HIV infection. The presence of some of these infections and tumors defines when a person is said to have developed AIDS.

Other manifestations of HIV infection can develop early in the disease. Some patients complain of fatigue and weight loss. No secondary infection can be found in many of these patients, and their illness is said to be due to HIV alone.

But most people who are in the latent phase of HIV infection (the period between infection and actual disease) have no complaints whatsoever. They have no physical signs that they have HIV infection at all. There is no way to determine that a patient is infected without a blood test (or one of the more recently introduced urine and saliva tests).

The fact that people are usually asymptomatic when they spread the infection is one of the main reasons that HIV has spread so efficiently throughout the population. Most of us would be able to avoid contracting the virus if everyone who could possibly transmit it had some visible sign like a chickenpox rash.

The problem is that there are millions of people in North America alone who appear well, yet can easily transmit HIV to others. Prevention methods such as condoms only go so far, because many people let their guard down when a partner appears perfectly healthy. They assume that such a healthy person could never be infected with a deadly virus such as HIV. As I have just explained, this can be a tragic mistake.