Effect of Co-infection – TB and HIV Treatment

HIV and TB coinfection

What is the link between HIV and TB?

When people have a damaged immune system, such as people with HIV who are not receiving antiretroviral treatment, the natural history of TB is altered. Instead of there being a long latency phase between infection and development of disease, people with HIV can become ill with active TB disease within weeks to months, rather than the normal years to decades.

TB is an opportunistic infection (OI). OIs are infections that occur more often or are more severe in people with weakened immune systems than in people with healthy immune systems. HIV weakens the immune system, increasing the risk of TB in people with HIV. Infection with both HIV and TB is called HIV/TB coinfection. In people with HIV, latent TB is more likely to advance to TB disease. TB disease may also cause HIV to worsen.

What is coinfection?

When a person has two or more infections at the same time. For example, a person infected with HIV may be coinfected with hepatitis C (HCV) or tuberculosis (TB) or both.
How common is HIV/TB coinfection?
Worldwide, TB disease is one of the leading causes of death among people with HIV. According to WHO statistics of 2015
  • Deaths from HIV and TB co-infection: 400,000
  • Deaths from TB alone: 1,400,000
  • Deaths from HIV alone: 800,000
So in 2015 more people died from TB than from HIV-related infections.

How TB is spread?

TB is primarily an airborne disease. When a person with active TB disease coughs, sneezes, speaks, or sings, TB germs spread through the air. These germs can float in the air for several hours. If you breathe in the air containing these TB germs, you can become infected. TB is NOT spread by:
  • Shaking someone’s hand
  • Sharing food or drink
  • Touching bed linens or toilet seats
Your chances are much greater if you’re around an infected person often, like someone you work with or live with. Tuberculosis spreads more easily in crowded places with little fresh air, too. Talk to your doctor about whether it’s safe for you to spend a lot of time somewhere like a hospital, clinic, doctor’s office, nursing home, jail or prison, or a shelter for homeless people. You’re also more likely to get active TB if you:
  • Are pregnant
  • Are younger than 5 years old or older than 65
  • Drink alcohol or inject drugs
  • Don’t eat well

How to prevent the transmission?

In order to reduce exposure in households where someone has infectious TB, the following actions should be taken whenever possible:
  • Houses should be adequately ventilated
  • Anyone who coughs should be educated on cough etiquette and respiratory hygiene and should follow such practice at all times
  • While smear positive, TB patients should:
    • Spend as much time as possible indoors
    • If possible, sleep alone in a separate, adequately ventilated room
    • Spend as little time as possible on public transport
    • Spend as little time as possible in places where large numbers of people gather together

How HIV in TB patient is treated?

Treatment with HIV medicines is called antiretroviral therapy (ART). ART protects the immune system and prevents HIV infection from advancing to AIDS. ART also has TB-related benefits:
  • ART reduces the risk of TB infection in people with HIV.
  • ART reduces the chances that latent TB will advance to TB disease in people with HIV/TB coinfection.
Without treatment, as with other opportunistic infections, HIV and TB can work together to shorten lifespan. Someone with untreated latent TB infection and HIV infection is much more likely to develop TB disease during his or her lifetime than someone without HIV infection. A person who has both HIV infection and TB disease has an AIDS-defining condition. People infected with HIV who also have either latent TB infection or TB disease can be effectively treated. The first step is to ensure that people living with HIV are tested for TB infection. If found to have TB infection, further tests are needed to rule out TB disease. The next step is to start treatment for latent TB infection or TB disease based on test results.

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