Infectious Diseases in India: Specialists

How are tuberculosis and HIV linked?

Dr. Neha Rastogi conducted a Jivo Masterclass on tuberculosis and HIV: an insight for international doctors on 30 March 2025 (masterclass, article series). Dr. Rastogi calls the two infections a double trouble: each raises the risk of the other, and in HIV tuberculosis appears in different forms with more drug resistance. Rifampicin, a key tuberculosis drug, interacts strongly with HIV drugs, which complicates treatment. A patient on antiretroviral therapy who develops tuberculosis starts antituberculosis treatment, is counselled to take every drug diligently, and has the viral load repeated after three months; therapy is switched only if the viral load stays high. Preventive therapy and vaccination are part of HIV care.

How is HIV diagnosed?

Dr. Rastogi sets out when each test turns positive: nothing is reliably detectable in the first two weeks, the viral load by PCR is the first to turn positive, the p24 antigen follows from about the second to the fourth week, and antibodies appear after four weeks. No single positive result labels a patient HIV positive. Three different tests must all be reactive, or two reactive and one indeterminate, with the indeterminate result settled by viral load. Early HIV looks like flu, with fever, sore throat, cough and swollen lymph nodes.

How is HIV treated today?

Having HIV is not the same as having AIDS, and antiretroviral therapy started at diagnosis halts progression. Dr. Rastogi sets two goals, the lowest possible viral load and a rising CD4 count, and treats every patient whatever the CD4 count. The standard regimen is a triple combination of two nucleoside backbone drugs with one integrase inhibitor, in a single daily pill, and the older regimens are gone. Newer options include a three-monthly injection for maintenance in stable patients and two-drug regimens, which reduce side effects. The regimen is built for the person, not the virus: tenofovir disoproxil can affect bone and kidney, so a patient with weak bones or kidneys needs another choice, and psychiatric medicines can interact with antiretrovirals. Failure is judged clinically, immunologically and virologically. Resistance testing is preferred but often unavailable, and in practice the patient is switched to a second-line regimen built on a protease inhibitor.

How can HIV be prevented before and after exposure?

Dr. Rastogi counsels that an undetectable viral load on treatment means HIV is not passed on sexually, and that social counselling matters most because of myths about sharing plates and sitting together. Pre-exposure prophylaxis is for HIV-negative adults at higher risk, including the partner of a person with HIV. Its protection depends on adherence. An on-demand schedule exists for infrequent exposure, with a caution that frequent use risks resistance and that condoms still matter. Long-acting injectable lenacapavir is a new prevention option.

After an exposure such as a needle-stick, post-exposure prophylaxis should start as soon as possible, preferably within three days, and must never wait for a test result, because a test on the day of exposure reflects earlier exposure, not this one. The regimen is three drugs for about four weeks, followed by an antibody test. For a pregnant woman with HIV, good therapy with viral suppression greatly lowers transmission, the infant receives prophylaxis, and breastfeeding is preferred only when the mother's viral load is suppressed.

What are the signs of tuberculosis, and when should a patient see an infectious diseases specialist?

Tuberculosis is caused by a bacterium that spreads through the air and most often affects the lungs. A cough lasting more than two weeks, fever, night sweats and weight loss are the usual signs, and it can also arise in lymph nodes, the spine, the abdomen and the lining of the brain. A rapid molecular test on sputum detects the bacterium and shows whether it resists rifampicin, and drug-resistant disease needs a regimen chosen from the resistance pattern and completed in full. An opinion is worth seeking for tuberculosis that has not responded to treatment, tuberculosis outside the lungs, tuberculosis with HIV, and a fever unexplained after the first round of tests.