The exposure to Covid-19 infection last year among people with HIV/AIDS was almost half that of the general population, according to a pre-print study of New Delhi's All India Institute of Medical Sciences (AIIMS). Antibody prevalence was found to be 14% among the 164 persons with HIV/AIDS, who visited the hospital for their anti-retroviral therapy, added the study uploaded to medRxiv, a free online archive, and distribution server.
The average seropositivity in Delhi was 25.7% at the time when the samples from persons with HIV/AIDS were collected between September and November 2020.
"This captures the data after the first wave of the infections; we do not know yet what happened during the massive second wave of infections. However, the lower infection prevalence among people with HIV is likely to be because they might have followed precautions more rigorously being at a higher risk of contracting infections," said Neeraj Nischal, associate professor, department of medicine at AIIMS.
Another reason ascribed by the study for the low prevalence of antibodies among the people living with HIV/AIDS is that the persons might not have generated antibodies after getting Covid-19 or might not have sustained it.
Delhi's population level seroprevalence shot up after November's surge in infections to over 56% in the January round. The scheduled April round of the survey was cancelled because of rising Covid-19 cases.
Another AIIMS study found a higher seroprevalence of 74.7% in urban areas of Delhi in March, again before the devastating wave of infections in April-May.
Interestingly, the study also found that majority of the patients had either no or minimal symptoms.
"We are still gathering evidence as to how Covid-19 affects people with HIV. Based on limited evidence, we believe people with HIV who are on effective HIV treatment and have suppressed viral load with good CD4 counts have the same risk of severity of Covid-19 as people who do not have HIV. So, it is important that all such people continue taking their anti-retroviral therapy," said Nischal.
A previous AIIMS study showed that over 97% of the patients had minor or no symptoms. In South Korea, more than 60% of the people with HIV were asymptomatic for Covid-19 at the time of diagnosis, according to the study.
Nischal warned that the small study from one centre should not be used to generalise trends across the country. Wider studies were needed to understand the impact of Covid-19 on people with HIV, he said.