Sarah Wulf Hanson, Cristiana Abbafati, Joachim G Aerts, Ziyad Al-Aly, Charlie Ashbaugh, Tala Ballouz, Oleg Blyuss, Polina Bobkova, Gouke Bonsel, Svetlana Borzakova, Danilo Buonsenso, Denis Butnaru, Austin Carter, Helen Chu, Cristina De Rose, Mohamed Mustafa Diab, Emil Ekbom, Maha El Tantawi, Victor Fomin, Robert Frithiof, Aysylu Gamirova, Petr V Glybochko, Juanita A. Haagsma, Shaghayegh Haghjooy Javanmard, Erin B Hamilton, Gabrielle Harris, Majanka H Heijenbrok-Kal, Raimund Helbok, Merel E Hellemons, David Hillus, Susanne M Huijts, Michael Hultström, Waasila Jassat, Florian Kurth, Ing-Marie Larsson, Miklós Lipcsey, Chelsea Liu, Callan D Loflin, Andrei Malinovschi, Wenhui Mao, Lyudmila Mazankova, Denise McCulloch, Dominik Menges, Noushin Mohammadifard, Daniel Munblit, Nikita A Nekliudov, Osondu Ogbuoji, Ismail M Osmanov, José L. Peñalvo, Maria Skaalum Petersen, Milo A Puhan, Mujibur Rahman, Verena Rass, Nickolas Reinig, Gerard M Ribbers, Antonia Ricchiuto, Sten Rubertsson, Elmira Samitova, Nizal Sarrafzadegan, Anastasia Shikhaleva, Kyle E Simpson, Dario Sinatti, Joan B Soriano, Ekaterina Spiridonova, Fridolin Steinbeis, Andrey A Svistunov, Piero Valentini, Brittney J van de Water, Rita van den Berg-Emons, Ewa Wallin, Martin Witzenrath, Yifan Wu, Hanzhang Xu, Thomas Zoller, Christopher Adolph, James Albright, Joanne O Amlag, Aleksandr Y Aravkin, Bree L Bang-Jensen, Catherine Bisignano, Rachel Castellano, Emma Castro, Suman Chakrabarti, James K Collins, Xiaochen Dai, Farah Daoud, Carolyn Dapper, Amanda Deen, Bruce B Duncan, Megan Erickson, Samuel B Ewald, Alize J Ferrari, Abraham D. Flaxman, Nancy Fullman, Amiran Gamkrelidze, John R Giles, Gaorui Guo, Simon I Hay, Jiawei He, Monika Helak, Erin N Hulland, Maia Kereselidze, Kris J Krohn, Alice Lazzar-Atwood, Akiaja Lindstrom, Rafael Lozano, Beatrice Magistro, Deborah Carvalho Malta, Johan Månsson, Ana M Mantilla Herrera, Ali H Mokdad, Lorenzo Monasta, Shuhei Nomura, Maja Pasovic, David M Pigott, Robert C Reiner, Grace Reinke, Antonio Luiz P Ribeiro, Damian Francesco Santomauro, Aleksei Sholokhov, Emma Elizabeth Spurlock, Rebecca Walcott, Ally Walker, Charles Shey Wiysonge, Peng Zheng, Janet Prvu Bettger, Christopher JL Murray, and Theo Vos
ImportanceWhile much of the attention on the COVID-19 pandemic was directed at the daily counts of cases and those with serious disease overwhelming health services, increasingly, reports have appeared of people who experience debilitating symptoms after the initial infection. This is popularly known as long COVID.ObjectiveTo estimate by country and territory of the number of patients affected by long COVID in 2020 and 2021, the severity of their symptoms and expected pattern of recoveryDesignWe jointly analyzed ten ongoing cohort studies in ten countries for the occurrence of three major symptom clusters of long COVID among representative COVID cases. The defining symptoms of the three clusters (fatigue, cognitive problems, and shortness of breath) are explicitly mentioned in the WHO clinical case definition. For incidence of long COVID, we adopted the minimum duration after infection of three months from the WHO case definition. We pooled data from the contributing studies, two large medical record databases in the United States, and findings from 44 published studies using a Bayesian meta-regression tool. We separately estimated occurrence and pattern of recovery in patients with milder acute infections and those hospitalized. We estimated the incidence and prevalence of long COVID globally and by country in 2020 and 2021 as well as the severity-weighted prevalence using disability weights from the Global Burden of Disease study.ResultsAnalyses are based on detailed information for 1906 community infections and 10526 hospitalized patients from the ten collaborating cohorts, three of which included children. We added published data on 37262 community infections and 9540 hospitalized patients as well as ICD-coded medical record data concerning 1.3 million infections. Globally, in 2020 and 2021, 144.7 million (95% uncertainty interval [UI] 54.8–312.9) people suffered from any of the three symptom clusters of long COVID. This corresponds to 3.69% (1.38–7.96) of all infections. The fatigue, respiratory, and cognitive clusters occurred in 51.0% (16.9–92.4), 60.4% (18.9–89.1), and 35.4% (9.4–75.1) of long COVID cases, respectively. Those with milder acute COVID-19 cases had a quicker estimated recovery (median duration 3.99 months [IQR 3.84–4.20]) than those admitted for the acute infection (median duration 8.84 months [IQR 8.10–9.78]). At twelve months, 15.1% (10.3–21.1) continued to experience long COVID symptoms.Conclusions and relevanceThe occurrence of debilitating ongoing symptoms of COVID-19 is common. Knowing how many people are affected, and for how long, is important to plan for rehabilitative services and support to return to social activities, places of learning, and the workplace when symptoms start to wane.Key PointsQuestionWhat are the extent and nature of the most common long COVID symptoms by country in 2020 and 2021?FindingsGlobally, 144.7 million people experienced one or more of three symptom clusters (fatigue; cognitive problems; and ongoing respiratory problems) of long COVID three months after infection, in 2020 and 2021. Most cases arose from milder infections. At 12 months after infection, 15.1% of these cases had not yet recovered.MeaningThe substantial number of people with long COVID are in need of rehabilitative care and support to transition back into the workplace or education when symptoms start to wane.