HIV infection: what is it?

HIV infection is a viral infection that progressively destroys the immune system, causing acquired immunodeficiency syndrome (AIDS) and other diseases that result from the impaired immunity.

Symptoms

Some people, within a few weeks of first contracting HIV infection, have symptoms that are similar to infectious mononucleosis. These symptoms generally last anywhere from 3 to 14 days:

• fever
• rashes
• swollen lymph nodes (may stay enlarged)
• muscle stiffness or aching
• fatigue
• sore throat

Symptoms that signal full-blown AIDS include:

• weight loss
• swollen lymph nodes
• a fever that comes and goes
• general unwell feeling
• recurring diarrhea
• anemia
• thrush - a fungal infection of the mouth

When does AIDS begin?

By definition, AIDS begins with a low CD4 + lymphocyte count (less than 200 cells per microliter of blood) or when opportunistic infections develop (infections that don't cause disease in people with a healthy immune system).

Diagnosis

A relatively simple, highly accurate blood test (called the ELISA test) can be used to screen people for HIV infection. If this test is positive, results are confirmed with more accurate and expensive blood tests such as a Western blot test. If the ELISA test is negative, it should be repeated within a few months since many people don't produce measurable antibodies right away.

Highly sensitive tests (P24 antigen) may also detect the virus.

Prognosis

To date, HIV can be treated but not cured. Exposure to HIV doesn't always lead to infection and many infected people have remained well for over a decade.

Treatment

Many drugs are now available to treat HIV infection, including:

• nucleoside reverse transcriptase inhibitors such as:
  • AZT (zidovudine)
  • ddl (didanosine)
  • ddC (zalcitabine)
  • d4T (stavudine)
  • 3TC (lamivudine)
• non-nucleoside reverse transciptase inhibitors such as nevirapine and delavirdine
• protease inhibitors such as saquinavir, ritonavir, or indinavir

All of these drugs prevent the virus from reproducing and thereby slow the progression of the disease. However, HIV usually develops resistance to all of these drugs when they are used alone after a few days to a few years, depending on the drug and the person. Treatment appears to be most effective when at least 2 of the drugs are given in combination.

Prevention

For uninfected people:

• avoid sexual contact with persons who have or are suspected of having AIDS or people who have multiple partners or who are IV drug users
• practice safe (protected) sex - use a condom

For HIV-positive people:

• abstinence from or practice safe (protected) sex
• avoid pregnancy
• notify previous and prospective partners
• do not donate blood or organs

For drug abusers:

• do not share or reuse needles
• start a drug treatment program

For medical and dental professionals:

• wear latex gloves whenever there is a possibility of contact with body fluids
• properly use and dispose of hollow needles