Preprint Long COVID in a highly vaccinated population infected during a SARS-CoV-2 Omicron wave - Australia, 2022, 2023, Woldegiorgis et al.

Long COVID in a highly vaccinated population infected during a SARS-CoV-2 Omicron wave - Australia, 2022
Mulu Woldegiorgis; Gemma Cadby; Sera Ngeh; Rosemary Korda; Paul Armstrong; Jelena Maticevic; Paul Knight; Andrew Jardine; Lauren Bloomfield; Paul Effler

Objective: To characterise Long COVID in a highly vaccinated population infected by Omicron.

Design: Follow-up survey of persons testing positive for SARS-CoV-2 in Western Australia, 16 July-3 August 2022.

Setting: Community Participants: 22,744 persons with COVID-19 who had agreed to participate in research at the time of diagnosis were texted a survey link 90 days later; non-responders were telephoned. Post stratification weights were applied to responses from 11,697 (51.4%) participants, 94.0% of whom had received >= 3 vaccine doses.

Main outcome measures: Prevalence of Long COVID defined as reporting new or ongoing COVID-19 illness-related symptoms or health issues 90 days post diagnosis; associated health care utilisation, reductions in work/study and risk factors were assessed using log-binomial regression.

Results: 18.2% (n=2,130) of respondents met case definition for Long COVID. Female sex, being 50-69 years of age, pre-existing health issues, residing in a rural or remote area, and receiving fewer vaccine doses were significant independent predictors of Long COVID (p < 0.05). Persons with Long COVID reported a median of 6 symptoms, most commonly fatigue (70.6%) and difficulty concentrating (59.6%); 38.2% consulted a GP and 1.6% reported hospitalisation in the month prior to the survey due to ongoing symptoms. Of 1,778 respondents with Long COVID who were working/studying before their COVID-19 diagnosis, 17.9% reported reducing/discontinuing work/study.

Conclusion: 90 days post Omicron infection, almost 1 in 5 respondents reported Long COVID symptoms; 1 in 15 of all persons with COVID-19 sought healthcare for associated health concerns >=2 months after the acute illness.

Link | PDF (Preprint: MedRxiv)

 

Published as —

Long COVID in a highly vaccinated but largely unexposed Australian population following the 2022 SARS-CoV-2 Omicron wave: a cross-sectional survey
Mulu Woldegiorgis; Gemma Cadby; Sera Ngeh; Rosemary J Korda; Paul K Armstrong; Jelena Maticevic; Paul Knight; Andrew Jardine; Lauren E Bloomfield; Paul V Effler

OBJECTIVES
To estimate the prevalence of long COVID among Western Australian adults, a highly vaccinated population whose first major exposure to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was during the 2022 Omicron wave, and to assess its impact on health service use and return to work or study.

STUDY DESIGN
Follow-up survey (completed online or by telephone).

SETTING
participants: Adult Western Australians surveyed 90 days after positive SARS-CoV-2 test results (polymerase chain reaction or rapid antigen testing) during 16 July – 3 August 2022 who had consented to follow-up contact for research purposes.

MAIN OUTCOME MEASURES
Proportion of respondents with long COVID (ie, reporting new or ongoing symptoms or health problems, 90 days after positive SARS-CoV-2 test result); proportion with long COVID who sought health care for long COVID-related symptoms two to three months after infection; proportion who reported not fully returning to previous work or study because of long COVID-related symptoms.

RESULTS
Of the 70 876 adults with reported SARS-CoV-2 infections, 24 024 consented to contact (33.9%); after exclusions, 22 744 people were invited to complete the survey, of whom 11 697 (51.4%) provided complete responses. Our case definition for long COVID was satisfied by 2130 respondents (18.2%). The risk of long COVID was greater for women (v men: adjusted risk ratio [aRR], 1.5; 95% confidence interval [CI], 1.4–1.6) and for people aged 50–69 years (v 18–29 years: aRR, 1.6; 95% CI, 1.4–1.9) or with pre-existing health conditions (aRR, 1.5; 95% CI, 1.4–1.7), as well as for people who had received two or fewer COVID–19 vaccine doses (v four or more: aRR, 1.4; 95% CI, 1.2–1.8) or three doses (aRR, 1.3; 95% CI, 1.1–1.5). The symptoms most frequently reported by people with long COVID were fatigue (1504, 70.6%) and concentration difficulties (1267, 59.5%). In the month preceding the survey, 814 people had consulted general practitioners (38.2%) and 34 reported being hospitalised (1.6%) with long COVID. Of 1779 respondents with long COVID who had worked or studied before the infection, 318 reported reducing or discontinuing this activity (17.8%).

CONCLUSIONS
Ninety days after infection with the Omicron SARSCoV-2 variant, 18.2% of survey respondents reported symptoms consistent with long COVID, of whom 38.7% (7.1% of all survey respondents) sought health care for related health concerns two to three months after the acute infection.

Link | PDF (Medical Journal of Australia) [Open Access]