Human Papilloma Virus (HPV) and HIV co-infection pose a daunting challenge

A study found that prevalence of human papilloma virus (HPV) among women living with HIV was 26.85% which was much higher than the HPV rates in HIV-negative women. Dr Ankita Chourasia, a researcher from Banares Hindu University (BHU) whose oral presentation of this study was awarded at the 6th National Conference of AIDS Society of India (ASICON 2013), strongly recommended regular HPV screening for women to cut down rates of HPV-caused cancers such as cervical cancer. HPV is the most common sexually transmitted infection (STI).

There are more than 40 types of HPV that can infect the genital areas of males and females. These HPV types can also infect the mouth and throat.  Most HPV infections (90%) go away by themselves within two years. But, sometimes, HPV infections will persist and can cause a variety of serious health problems. Health problems that can be caused by HPV include: genital warts; cervical cancer (cancer on a woman's cervix); and cancers of the vulva, vagina, penis, or anus; and a type of head and neck cancer called oropharyngeal cancer.

There is a way to identify people with HPV who have pre-cancer lesions but cancer may not have set in as yet. Pap-smear examination can detect pre-cancerous changes in cervix due to HPV, such as mild dysplasia or cervical intraepithelial neoplasia (CIN1) to moderate CIN2 to high-grade lesions (CIN3). If left untreated these pre-cancers have the propensity to invade and become cancerous.

Dr Joel Palefsky, Professor of Medicine, University of California, San Francisco said that initial HPV infection may root in years before invasive cervical or anal cancers may begin manifestation. There are host of factors that may fuel progression of HPV to serious cancerous manifestations such as factors related the virus (variants of HPV, viral load, etc), use of oral contraceptive pills, smoking, chlamydia infection, HSV-2 co-infection, dietary factors among others.

Dr Joel Palefsky added that according to the “Globocan 2012”, cervical cancer was the second-biggest cause of death among women in India (breast cancer continues to be biggest cause of mortality among cancers in women in India). Dr Joel added that cancer is a growing cause of mortality in people living with HIV PLHIV). “People are living longer and have time for cancer events to occur” said Dr Palefsky. Rates of all kinds of cancers have gone up from 29% to 34% between the years 2000-2005. Anal cancer rates among HIV-negative men who have sex with men (MSM) are up to 35/ 100,000, which is 3-4 times higher than the cervical cancer rates in HIV-negative women (cervical cancer rates currently stand at 8-10/100,000). Similarly anal cancer rates in a North American study were 131/100,000 among MSM; 46/100,000 among men who have sex with women; and 30/100,000 among women. Key populations such as MSM are at risk of getting HPV infection through anal route said Dr Palefsky.

In another study done in San Francisco, anal HPV rates among HIV-positive MSM were 88%, out of which 72% had cancer-causing HPV. In studies done in India in Tamil Nadu and Mahrashtra, HPV rates were no less alarming among HIV-positive MSM at over 90%.

Dr Taweewat Supindham from Research Institute for Health Sciences in Chiang Mai University had earlier told Citizen News Service (CNS) at 11th International Congress on AIDS in Asia and the Pacific (11th ICAAP): “although HPV rates in Thai women were 8.7% but in MSM and transgender people in northern Thailand anal HPV rates shot up to 80%. There are more than 40 types of ano-genital HPV including at least 13 high risk types of HIV. HPV infection is associated with cervical cancer and anal cancer.” Recently HPV vaccination has been implemented for young women but not available for MSM or transgender people in Thailand. But CDC does recommend providing routine use of quadrivalent HPV vaccine in boys.

Dr Palefsky said that we need to do more research to find if starting antiretroviral therapy (ART) early prevents formation of pre-cancerous lesions related to HPV.

Dr Palefsky said that there are benefits of vaccinating boys and girls both against HPV which can perhaps reduce HPV related cancer rates by 90%. Boys too get HPV related cancers such as those of anal, penile or oral. HPV vaccine is also very effective (77% reduction) in preventing anal HPV in MSM. Dr Palefsky shared another study where proportion of people coming with genital warts had declined sharply when HPV vaccine was rolled out in Australia. In US, only a third of women who should be vaccinated get the HPV vaccine. Still there were significantly lower proportions of CIN2+ lesions, a pre-cancerous stage to cervical cancer.

Dr Palefsky warned that HPV related cancers in HIV infected men and women will likely continue to rise among those who are not being routinely screened and vaccinated; and those who are HIV-positive and starting on ART at relatively lower CD4 count.

HPV vaccination before onset of sexual activity offers the best long term solution to prevention of HPV and HPV related cancers, argued Dr Palefsky.

Dr Sudeep Gupta, Professor, Department of Medical Oncology, Tata Memorial Hospital, said that cervical cancer rates have been consistently coming down. Dr Gupta’s data was based upon pan-India cancer registry. Dr Gupta argued since HPV vaccination is not available as part of government of India’s immunization programme, the decline in cervical cancer rates in India is comparable to countries where girls get vaccinated for HPV, a main cause for cervical cancers. Dr Gupta strongly advocated to push-up cervical cancer screening (by doing regular pap-smear examination of women).

Dr Dilip Mathai, a senior Physician who was formerly with Christian Medical College (CMC), Vellore, informed that the present HPV vaccine is active against the most prevalent strains of HPV in India. But this vaccine is very expensive (INR 3500) and not part of government’s immunization programme. Also India is not yet receiving these vaccines at subsidized rates from GAVI because of certain concerns raised by researchers. Dr Mathai said that there were 4 deaths among young women who got HPV vaccine shots but investigators found that these deaths were not related to HPV vaccine rather suicides (one committed suicide by jumping in a well, and other 3 girls suicided by consuming organophosphate). Dr Mathai hoped for early clearance to roll-out HPV vaccines as part of the government’s programme.

Bobby Ramakant, Citizen News Service - CNS
December 2013

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