LAUSR

The COVID19 pandemic started in London during the latter part of January 2020 and reached its peak in April 2020. Antibodies to the SARSCoV2 develop 2–3 weeks after exposure and decreases following recovery from illness. In the UK, patients accessing the National Health Service were able to request SARSCoV2 antibody testing since May 2020. Patients attending our HIV clinic were able to optin for SARSCoV2 antibody testing during their routine monitoring visit for blood tests. Laboratory tests were used to detect SARSCoV2 nucleic acid antibodies in serum samples. A retrospective study was conducted to know the seropositivity rate among the tested cohort of our large central London HIV clinic. We collected data of people living with HIV who optedin for SARSCoV2 antibody test from 1 May 2020 to 31 December 2020. Data on demographics, body mass index (BMI), comorbidities, concomitant medications, Antiretroviral therapy (ART), CD4 count and HIV viral load, symptoms of COVID19 and hospital admissions were collected for people who tested positive for antibodies. The test result was considered negative when reported as inconclusive. A total of 2567 (65.9%) people optedin for the SARSCoV2 antibody test. Among them, 271 (10.6%) were tested positive; male: 162 (59.8%), female: 109 (40.2%), Men who have sex with men (MSM): 97 (35.7%). Median age was 50 years (range 20–76 years); ethnicity—black, Asian and minority ethnic group 189 (69.7%), white 73 (26.9%), others 5 (1%), undisclosed ethnicity: 4 (1%). Prevalence of SARSCoV2 antibodies among the tested cohort from August 2020 to December 2020 is summarised in table 1. Out of 271 people, 270 (99.6%) were on prescribed ART and 267 (98.5%) had HIV viral load less than 200 copies/ mL. Median CD4 count was 554 cells/μL (range 70–1338 cells/μL). Demographics and individual antiretroviral exposure in this cohort are summarised in online supplemental tables 2 and 3, respectively. Among those who tested positive for SARSCoV2 antibody, past symptoms of COVID19 were reported by 111 (41%) people. Eleven (4%) people had severe COVID19 manifestations requiring inpatient medical care and five (1.8%) had an intensive care admission. Comorbidities are summarised in online supplemental tables 4 and 5. Data on BMI were not available for all people included in this study. Data on symptoms were not available for 92 (34%) people. Seropositivity rate for SARSCoV2 antibodies among our tested cohort during the epidemic was not significantly different from the corresponding general population prevalence in London. Prevalence data published by the Office of National Statistics were from a randomly selected subsample of individuals aged 16 years and older who volunteered for blood test for SARSCoV2 antibodies and excluded participants from care home, hospitals and institutions. The estimates were weighted to represent the overall population of London and published. In comparison, the results in this retrospective study were from a large subset of people registered at a single HIV clinic located at central London who optedin for a SARSCoV2 antibody test during their routine clinic visit. There was no significant attributable risk due to HIV in developing antibodies to SARSCoV2. Our study findings were unique as the population was unexposed to any COVID19 vaccine during the study period. The difference in attributable risk in the month of December 2020 could be due to the lesser number of people tested for this month. Symptomatic COVID19 illness was reported by 44% in this cohort which was lower than the published reports for the general population. This difference could be due to the lack of data on reported symptoms for the whole study group in our study. Higher proportion of men reported symptoms than women in our clinic which was similar to other studies. Four per cent of our tested cohort required inpatient care for severe COVID19. People admitted to the hospital had concomitant comorbidities which could have contributed to the severity of the illness. This proportion was lower when compared with other studies conducted among PCR positive general population (14%). Although there was a survivor bias in our study, a previous study in our HIV clinic did not report excess mortality due to COVID19 than those without HIV. Lack of protective effect from SARSCoV2 infection was reported for people on Preexposure prophylaxis (PrEP) from previous studies. Our SARSCoV2 antibody seropositive cohort had exposure to tenofovir (64.6%) and protease inhibitors (27.4%). However, this study was not designed to explore the association between individual ART drug and SARSCoV2 antibodies seroconversion. The findings from this study should be interpreted in relation to the methodology and the characteristics of the virologically suppressed cohort.