COVID-19 vaccine and booster highly effective in people living with HIV, large studies show

Two studies published this month confirm that people living with HIV who are vaccinated against COVID-19 have a low risk of serious illness or death, and both studies show that a third dose of the SARS-CoV-2 vaccine reduces one offers even greater protection.

The results come from two large cohort studies. The Corona-Infectious-Virus Epidemiology Team (CIVET-II) study examined the post-vaccination outcome of COVID-19 in people living with HIV in the United States who were fully vaccinated as of June 30, 2021. A Danish national cohort study of people living with HIV looked at COVID-19-related outcomes in everyone living with HIV, including data during the Omicron wave earlier this year.

The studies provide evidence of the risk of serious COVID-19 illness or death after vaccination, including the impact of a third dose of vaccine, in people living with HIV.

Public health authorities in the United States and Europe have recommended that some people living with HIV receive a third dose of vaccine as part of their primary immunization routine. A third dose may be needed by people who do not respond well to a two-dose vaccination course.

People with low CD4 counts (below 200), a current AIDS-related illness or a detectable viral load should receive a third dose of vaccine in the UK.

Booster doses given at least three months after the primary vaccination course have been recommended by the British HIV Association for all people living with HIV.

Severe post-vaccination COVID-19 in the United States, 2021

The US study sought full vaccination against COVID-19 in 33,029 people living with HIV and 80,965 people living without HIV, matched for age, sex, race and ethnicity, for cases of severe COVID-19, described as a “breakthrough disease”. . “Full vaccination” was defined as two doses of Pfizer or Moderna vaccines or one dose of Johnson & Johnson. The study combined data from four cohorts.

By the end of 2021, 3,649 cases of COVID-19 had emerged in fully vaccinated individuals (15% had received a third dose), 1,241 in those living with HIV and 2,408 in those not living with HIV. A similar proportion in each group diagnosed with COVID-19 were hospitalized (7%), required mechanical ventilation (about 10% of those admitted), or died as a result of COVID-19 (1% of all cases) . The incidence rate of severe COVID-19 was similar in people living with HIV (117 cases per 100 person-years of follow-up) and people without HIV (138 cases per 100 person-years of follow-up).

The risk of major breakthrough disease was slightly higher (9%) in people who received Johnson & Johnson’s single-dose vaccine than in those who received Pfizer’s (7%) or Moderna’s (6%) vaccines. Regardless of which vaccine they received, people who received a third dose had a significantly lower risk of breakthrough disease — particularly people living with HIV. People with a history of COVID-19 before vaccination also had a lower risk of breakthrough diseases.

People living with HIV with CD4 counts below 350 had a 59% higher risk of a severe outbreak of COVID-19 compared to people without HIV, but there was no difference in risk between people living with HIV with CD4 counts above 350 and people without HIV.

When comparing risks between people living with HIV, the researchers found that after adjusting for demographic factors, vaccine type, COVID-19 history, and underlying medical conditions, people with CD4 counts between 200 and 349 had a 65% greater risk of major breakthrough than People with CD4 counts over 500. People with CD4 counts under 200 were two and a half times more likely to develop serious illnesses. The lack of viral suppression did not increase the risk of breakthrough disease.

People with CD4 counts below 350 were also at higher risk of requiring mechanical ventilation and dying after hospitalization, although absolute numbers were small.

Women living with HIV were three times more likely to develop major breakthrough diseases than men. The study’s researchers say the higher prevalence of obesity in women with HIV compared to men in these cohorts could explain the higher risk. People with HIV who had cancer were twice as likely to have a major breakthrough.

Based on their findings, the CIVET study researchers say the recommendation for an additional dose of vaccine for people living with HIV who are immunosuppressed should be expanded to include people with CD4 counts in the 200-350 range.

Severe COVID-19 and death from COVID-19 in Denmark, 2020-2022

Danish researchers used their national HIV cohort data to assess the impact of vaccination on SARS-CoV-2 infection, hospitalization and death in people living with HIV and a control group of people without HIV. They were able to capture the effect of a booster shot (a third dose offered to everyone in Denmark) up until the end of April 2022, providing information on the effect of the shot during the Omicron variant wave that hit Europe from December 2021.

The study included 5,246 people with HIV and a control group of 42,208 people without HIV, matched for age and sex. The participants were predominantly male (70%) and middle-aged (mean age 51 years). People living with HIV were slightly more likely to have had serious comorbidities, such as a history of heart attack or other cardiovascular disease, severe kidney disease or diabetes, or current cancer than the general population, although only 7% of people living with HIV were classified as patients with high scores of comorbidities classified.

A large proportion of people living with HIV in this cohort had a history of low CD4 counts (45%), but only 4% had a current CD4 count below 200.

Since the start of the pandemic, people living with HIV have had a 20% lower risk of testing positive for SARS-CoV-2 but a 30% higher risk of getting a second positive test compared to the general population. When they recorded the time of infection, the researchers observed that the increased risk of a first and second positive test in people living with HIV only appeared during the 2022 Omicron wave.

People living with HIV were about twice as likely to be hospitalized with COVID-19 and hospitalized with severe COVID-19 that required mechanical ventilation as compared to the general population.

The risk of hospitalization for people living with HIV decreased over time, resulting in a 70% lower risk in the first half of 2022 compared to 2020. The study leaders say this reduction in the risk of hospitalization is largely due to vaccination.

The study population had a high vaccination coverage. Ninety-one percent of people living with HIV and 91 percent of the general population control group had received two doses of vaccine by May 2022. Eighty-eight percent of both groups had received three doses.

Comparing people with HIV who received a booster dose versus those who didn’t, the researchers found that a booster shot reduced the risk of testing positive by 10% and the risk of death by 80% — but only for people over 60 years of age. A booster dose did not significantly reduce the risk of hospitalization.

The authors believe this is the first study to use comprehensive national data from the onset of the COVID-19 pandemic to compare outcomes between people living with HIV and the general population.