HIV and TB: Understanding the Link and Prevention Strategies

1. HIV AND TB

2. Tuberculosis • Caused by bacterium called Mycobacterium tuberculosis • Usually attacks lungs, but can attack any part of the body, such as kidney, spine, brain • Can be fatal if not treated

3. Transmission • Through the air: person to person (coughing, sneezing, singing) • People nearby inhale bacteria and become infected But not through: • Shaking hands • Sharing food or drink • Bed linens or toilet seats • Sharing toothbrushes • Kissing

4. 2 TB-related Conditions • Latent TB infection (LTBI) • TB Disease

5. Latent TB Infection • TB bacteria lives in body but doesn’t make person sick • No symptoms • Positive reaction to tuberculin skin test or special TB blood test • Not infectious • If bacteria becomes active, person WILL become sick w/TB disease

6. TB Disease • TB Bacteria are active (multiplying in body) • People w/bacteria may spread it to any people they spend time with • Some can have disease soon after becoming infected (within weeks) before immune system can fight the TB bacteria • Others get sick years later, when immune system becomes weak for other reasons • Risk is higher for those w/weak immune systems (i.e., HIV)

7. Comparison Between Latent Infection and TB Disease

8. Comparison Between Latent Infection and TB Disease

9. Treatment • For Latent TB Infection • Though no TB disease, to prevent development of TB disease in the future, often prescribed treatment. • Less bacteria present, so treatment relatively easy • INH (isoniazid) • Preferred regiment of 9 months • Children and people w/HIV may need to take INH for longer

10. Treatment • For TB Disease • Large amount of bacteria present • Several drugs can be used, for 6-12 months • Drugs must be taken exactly as prescribed • Must finish course of treatment or germs that are still alive may become resistant to the drugs • TB that is resistant to drugs is harder and more expensive to treat

11. Testing & Diagnosis • TB Blood Tests • aka Interferon-Gamma release assays or IGRAs • Measures how the immune system reacts to the bacteria that causes TB • Only 1 visit required • Results in 24-48 hrs • Mantoux tuberculin skin test • Small amount of tuberculin injected into skin in lower part of the arm • Must return w/in 48-72 hrs to have health care provider observe reaction on arm

12. Who Should Get Tested • Have spent time w/person known or suspected to have active TB disease • Have HIV or other problem w/weakened immune system • Have symptoms of active TB disease • From a country where active TB disease is common (Latin America, Africa, Asia, Eastern Europe, Russia) • Live in areas where active TB disease is more common---homeless shelters, migrant farm camp, prison or jail, some nursing homes • Inject illegal drugs

13. TB and HIV Co-infection • TB is one of leading causes of death among people infected w/HIV • HIV and TB can work together to shorten the life of an infected person • A person w/untreated latent TB infection and HIV is much more likely to develop active TB disease than someone w/out HIV • Among those w/latent TB infection, HIV infection is the strongest known risk factor for progressing to active TB disease • Can be effectively treated

14. LINK between STDs and HIV • Individuals infected with STDs are 2-5 Xs more likely than uninfected individuals to acquire HIV infection if they are exposed to the virus through sexual contact • If an HIV-infected person is also infected w/another STD, that person is more likely to transmit HIV through sexual contact than another HIV-infected person The presence of other STDs increases the likelihood of both transmitting and acquiring HIV

15. Link between STDs and HIV • Increased Susceptibility • Increased Infectiousness

16. STD Treatment slows the spread of HIV • STD treatment reduced an individual’s ability to transmit HIV • Herpes can make people more susceptible to HIV infection, and make HIV-infected people more infectious

17. Implications for HIV Prevention • Early detection and treatment of curable STDs should become a major, explicit component of comprehensive HIV prevention programs at national, state, and local levels; • In areas where STDs that facilitate HIV transmission are prevalent, screening and treatment programs should be expanded; • HIV testing should always be recommended for individuals who are diagnosed with or suspected to have an STD. • HIV and STD prevention programs in the United States, together with private and public sector partners, should take joint responsibility for implementing these strategies.