There is no scientific evidence to back a widely shared claim on social media that COVID boosters can lead to HIV, a supposition attributed to French virologist Luc Montagnier, say, experts.

Montagnier, a joint recipient of the 2008 Nobel Prize in Medicine for his discovery of the human immunodeficiency virus (HIV) that can lead to AIDS, died earlier this month. Since then, several Twitter users have shared a quote attributed to him which reads, "For those of you that have taken the third dose, go and take a test for AIDS. The results may surprise you. Then sue your government".

There is no evidence he made this claim or that COVID booster make a person susceptible to HIV infection, several experts told PTI. I don't see why would a booster lead to a positive HIV test. We should not be carried away by misinformation and information that are not evidence-based, said virologist Upasana Ray, senior scientist at Kolkata's CSIR-Indian Institute of Chemical Biology.

Immunologist Vineeta Bal agreed, saying COVID vaccines do not in any way promote susceptibility to HIV infection. Bal added that there was nothing to indicate that Montagnier made the claim. There is no evidence that vaccines cause immunosuppression thereby leading to activation of dormant HIV infection either. There can be isolated individuals who test HIV positive but that is likely to be by chance rather than design, Bal, from Pune's Indian Institute of Science Education and Research, told PTI.

According to virologist Naga Suresh Veerapu, no scientific evidence to date suggests a link between increased chances of HIV infection after COVID vaccination. On a related note, COVID vaccination neither can cause infection with SARS CoV-2 nor with the virus used as the vector for vaccine preparation, Veerapu, associate professor at Shiv Nadar University, Delhi-NCR, told PTI.

Viral vector vaccines use a modified version of a virus that is different from the virus being targeted to deliver instructions to our cells to tackle the pathogen. Last year, a COVID vaccine developed by the Australia's University of Queensland and biotech firm CSL was found to interfere with HIV tests, but routine follow-up tests confirmed there was no HIV virus present.

Bal said the vaccine, which was discontinued after the phase 1 clinical trial, used a component of HIV called gp41 as a part of the COVID-19 vaccine. Naturally, the recipients would develop antibodies to gp41. This was a point that was anticipated and the clinical trial volunteers were briefed about it so that alarm bells do not ring, she said.

Ray noted that the shelved Australian vaccine should not fuel false claims about authorised COVID-19 vaccines in use around the world. Each vaccine candidate is designed differently and if for one a cross-reactivity is found, that doesn't prove that the COVID vaccine triggers HIV, she explained. Veerapu said government agencies can run a small clinical trial screening for blood HIV antigen or antibodies prior and after COVID vaccination to promote confidence about the safety of the vaccines.