To follow SARS-CoV-2-infected persons up to 18 months after a positive test in order to assess the burden and nature of post acute symptoms and health problems.

Persons in Denmark above 15 years of age, who were tested positive for SARS-CoV-2 during 1 September 2020 to 21 February 2023 using a RT-PCR test. As a reference group, three test-negative individuals were selected for every two test-positive individuals by matching on test date.

In total, 2 427 913 invitations to baseline questionnaires have been sent out and 839 528 baseline questionnaires (34.5%) have been completed. Females, the age group 50–69 years, Danish-born and persons, who had received at least one SARS-CoV-2 vaccination booster dose were more likely to participate. Follow-up questionnaires were sent at 2, 4, 6, 9, 12 and 18 months after the test, with response rates at 42%–54%.

New participants have been recruited on a daily basis from 1 August 2021 to 23 March 2023. Data collection will continue until the last follow-up questionnaires (at 18 months after test) have been distributed in August 2024.

Oral pre-exposure prophylaxis (PrEP) is a highly effective HIV prevention method; however, uptake and persistence have been low among southern African women. A dual prevention pill (DPP) that combines PrEP with oral contraception (OC) may increase PrEP use and better meet women’s sexual and reproductive health needs. We will gauge the DPP’s acceptability in two cross-over clinical trials.

PC952 (Zimbabwe) and PC953 (South Africa) will compare acceptability, adherence and preference for an over-encapsulated DPP versus PrEP and OCs taken separately. HIV-negative, non-pregnant cisgender females in Johannesburg, South Africa (n=96, 16–40 years) and Harare, Zimbabwe (n=30, 16–24 years) will be randomised 1:1 to the order of regimens—DPP or two separate tablets—each used for three 28-day cycles, followed by a 6-month choice period in South Africa. Monthly clinic visits include HIV and pregnancy testing; safety assessments and risk reduction and adherence counselling. We will assess adherence (monthly) based on tenofovir diphosphate drug levels in dried blood spots and by self-report. We will evaluate acceptability (monthly) and preference (end of cross-over) via computer-assisted self-interviewing and in-depth interviews with a subset of participants. Data collection started in September 2022 and ended in January 2024.

PC952 was approved by the Ministry of Health and Child Care, Medical Research Council, Research Council and Medicines Control Authority of Zimbabwe; the Chitungwiza City Health Ethics Committee; and the Joint Research Ethics Committee for the University of Zimbabwe Faculty of Medicine and Health Sciences and Parirenyatwa Group of Hospitals. PC953 was approved by the South African Health Products Regulatory Authority and the University of the Witwatersrand’s Human Research Ethics Committee. The Population Council IRB approved both studies. We will disseminate results in open-access journals, clinical trials registries, and at local and international meetings and conferences.

NCT04778514, NCT04778527.