Globally, there were approximately 35.3 [32.2–38.8] million people living with HIV in 2012. The adult HIV prevalence at national level is 0.27% as estimated in 2011 and has recently been estimated that 2.5 million individuals are living with HIV infection in India. The depletion of T-lymphocytes which result from the proliferation of HIV causes the immune system to become severely compromised and the usually benign infectious agents become pathogenic. A number of microorganisms can be responsible for such opportunistic infections (OIs) in HIV-infected persons who have progressed to AIDS. The Antiretroviral Therapy (ART) started in the mid 1990s was instrumental in reducing the mortality related to HIV infection. ART not only reduces the incidence of OIs but also improves survival rate of PLHIVs.
Globally, more than 9.7 million people living with HIV in low and middle income countries were receiving ART at the end of 2012. Of this, about 640 000 were children. In India, Treatment of Opportunistic Infections (OI) is one of the main goal of comprehensive management to People living with HIV/AIDS (PLHIV) served through Care, Support and Treatment (CST) component of the, National AIDS Control Programme (NACO), Department of AIDS Control, Government of India. Under this initiative, patients have been provided access to free antiretroviral therapy (ART) for a decade (India had its first functional ART center in April’ 2004) and around 7.5 lakhs patients are receiving free ART therapy (second highest in the world) through 425 ART centers, 840 Link ART centers, 37 ART plus centres and 10 Center of Excellence (CoE) till March 2014. In Delhi, the number of PLHIV Alive and on First line ART by the end of March 2014 were 16038 among which 1021 were children below 15 years of age. As per World Health Organisation (WHO), online data record of Oct 2013, the most common life-threatening opportunistic infection affecting people living with HIV/AIDS is Tuberculosis (TB). Oral candidiasis, herpes zoster, cryptococcal meningitis, cerebral toxoplasmosis, and cytomegalovirus retinitis includes other commonly reported OIs. Hence the present study was carried out to find out the most common opportunistic pathogen and different opportunistic pathogens infecting HIV seropositive patients in Delhi region, India.