Evidence map›Paper›PMID 41699511›Full record

ArticleBMC infectious diseases2026

Prevalence, symptoms, and associated factors of long COVID: a retrospective cohort study based on data from two major German health authorities.

Kira Engl, Sven Feddern, Barbara Grüne, Luis Haberstock, Annelene Kossow, Johannes Nießen, Susanne Rost, Gerhard A Wiesmüller, Nikola Schmidt, Christine Joisten

Abstract read
In one paragraph

Article in BMC infectious diseases, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

Kira EnglDepartment of Infection Control and Environmental Hygiene, Cologne Health Authority, Cologne, Germany. kira-engl@web.de.ORCID http://orcid.org/0009-0006-8038-0200
Sven FeddernDepartment of Infection Control and Environmental Hygiene, Cologne Health Authority, Cologne, Germany.
Barbara GrüneDepartment of Infection Control and Environmental Hygiene, Cologne Health Authority, Cologne, Germany.ORCID http://orcid.org/0000-0003-4393-333X
Luis HaberstockAugsburg County Health Authority, Augsburg, Germany.
Annelene KossowDepartment of Infection Control and Environmental Hygiene, Cologne Health Authority, Cologne, Germany.ORCID http://orcid.org/0000-0002-4648-4851
Johannes NießenDepartment of Infection Control and Environmental Hygiene, Cologne Health Authority, Cologne, Germany.
Susanne RostAugsburg County Health Authority, Augsburg, Germany.
Gerhard A WiesmüllerDepartment of Infection Control and Environmental Hygiene, Cologne Health Authority, Cologne, Germany.
Nikola Schmidt *Department for Physical Activity in Public Health, German Sport University Cologne, Institute of Movement and Neurosciences, Am Sportpark Müngersdorf, 650933, Cologne, Germany.ORCID http://orcid.org/0000-0001-8739-8354
Christine Joisten *Department of Infection Control and Environmental Hygiene, Cologne Health Authority, Cologne, Germany.ORCID http://orcid.org/0000-0002-2455-8901

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundAcute SARS-CoV-2 infection has caused substantial morbidity and mortality worldwide. As the pandemic subsided, persistent symptoms gained increasing attention. Time-based definitions distinguish ongoing symptomatic COVID-19 (weeks 4–12) from post-COVID syndrome ( > 12 weeks). Consistent with these time-based definitions, long COVID is commonly used as an umbrella term for symptoms persisting for ≥4 weeks post-infection (including ongoing symptomatic COVID-19 and post-COVID-19 syndrome). Reported prevalence estimates vary widely, with meta-analyses suggesting 43–80% for persistent symptoms, mainly based on data from hospitalised patients. However, evidence on long COVID among nonhospitalised adults in Germany remains limited. The aim of this study was to estimate the prevalence, symptoms, and associated factors of long COVID among quarantined adults in two German regions, including the early post-acute phase (4–12 weeks), a key predictor of post-COVID syndrome.

methodsWe conducted a retrospective cohort study based on an online questionnaire to estimate the prevalence, symptoms, and associated factors of long COVID. We included 6846 adults with a laboratory-confirmed SARS-CoV-2 infection in 2021 who were reported to the health authorities in Cologne and Augsburg (Germany) and subsequently enrolled in the CoCo-Fakt online monitoring study.

resultsThe prevalence of long COVID was 14.6% (n = 997), with women being significantly more affected than men (16.4% vs 11.8%, p < 0.001). The most reported symptoms were fatigue (76.8%, n = 763), concentration and cognitive impairment (60.1%, n = 597), and dyspnoea (48.9%, n = 486). Chronic diseases (odds ratio [OR] = 1.563; p < 0.001; 95% CI: 1.2–2.0) and the severity of acute symptoms (OR = 141.809 in severe cases; p < 0.001; 95% CI: 19.8–1016.7) were identified as factors significantly influencing the occurrence of long-term symptoms (Nagelkerke R2 = 0.19).

conclusionIndividuals, especially women, with pre-existing chronic conditions or severe acute SARS-CoV-2 infection were particularly affected. Targeted screening of high-risk groups can facilitate early detection and personalised care, helping identify the need for early intervention to prevent the development of post-COVID syndrome. CLINICAL TRIAL NUMBER: Not applicable.

Indexed as

COVID-19AdultAgedFemaleGermanyHumansMaleMiddle AgedPost-Acute COVID-19 SyndromePrevalenceQuarantineRetrospective StudiesRisk FactorsSARS-CoV-2Surveys and QuestionnairesCOVID-19GermanyLong COVIDPrevalenceRisk factor

Identifiers

PMID41699511
PMCPMC13011314

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.