Evaluating the massive underreporting and undertesting of COVID-19 cases in multiple global epicenters
Open accessAbstract
BACKGROUND: With continuous global COVID-19 outbreak, differing case numbers and mortality rates are observed. While actual case numbers appear vague, mortality numbers related to COVID-19 seem more precise. In this study, we used the mortality rate as the main indicator to evaluate the extent of underreporting and underdetection of COVID-19 cases. METHODS: We have analyzed all available data provided by the World Health Organization on the development of international COVID-19 cases and mortality numbers on March 17th, 2020. A crude case-fatality risk (cCFR) and adjusted case-fatality risk (aCFR) was calculated for China, South Korea, Japan, Italy, France, Spain, Germany, Iran and the United States. Additionally, a fold-change (FC) was derived for each country. RESULTS: The highest aCFR and FC were detected for Spain. Based on their FC values, an extremely high number of undetected COVID-19 cases was displayed in France, the United States, Italy and Spain. For these countries, our findings indicate a detection rate of only 1-2% of total actual COVID-19 cases. CONCLUSIONS: Due to limited testing capacities, mortality numbers may serve as a better indicator for COVID-19 case spread in many countries. Our data indicate that countries like France, Italy, the United States, Iran and Spain have extremely high numbers of undetected and underreported cases. Differences in testing availability and capacity, containment as well as overall health care and medical infrastructure result in significantly different mortality rates and COVID-19 case numbers for each respective country.
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Early in the pandemic, many deaths due to COVID-19 among older individuals in high-income countries, particularly in long-term care facilities, are unlikely to have been attributed to COVID-19.
“early in the pandemic, before tests were widely available, many deaths due to COVID-19 among older individuals in high-income countries, particularly in long-term care facilities, are unlikely to have been attributed to COVID-19”
From Estimating excess mortality due to the COVID-19 pandemic: a systematic analysis of COVID-19-related mortality, 2020–21 (2022) · cites this paper as [4]
The Discussion (page unavailable) reports retrospective corrections of COVID-19 death counts and unexplained rises in deaths recorded as non-COVID-19, often with unspecified pneumonia listed as the cause. This supports concern about missed attribution early in the pandemic, but the paper does not identify those deaths as COVID-19 deaths or establish that they occurred particularly among older people or long-term care residents. (LLM, conf=0.85)
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Wang, H., Paulson, K. R., Pease, S. A., Watson, S., Comfort, H., Zheng, P., Aravkin, A. Y., Bisignano, C., Barber, R. M., Alam, T., et al. (2022) · The Lancet · doi:10.1016/s0140-6736(21)02796-3 · Cited by 2,069 · see citing works
“…Database, and the European Statistical Office, and identified 74 countries and territories and an additional 266 subnational locations where either weekly or monthly all-cause mortality data were reported for periods in 2020 and 2021, and for up to 11 years previously (appendix pp 4–8, 47).”
- Authors
- Lau, H., Khosrawipour, T., Kocbach, P., Ichii, H., Bania, J., & Khosrawipour, V.
- Affiliations
- University of California, Irvine (US)
- University of Warmia and Mazury in Olsztyn (PL)
- Wrocław University of Environmental and Life Sciences (PL)
- Corresponding author
- Khosrawipour, T.
- Venue
- Pulmonology
- Publisher
- Informa UK Limited
- Published
- 2021-03-30
- Volume
- 27
- Issue
- 2
- Pages
- 110-115
- ISSN
- 2531-0429 (ISSN-L)
- 2531-0437
- PMC
- PMC7275155
- OpenAlex
- W3032946145
- Cited by
- 335
- References
- 1
- Citations by year
- 2026: 12 · 2025: 33 · 2024: 32 · 2023: 77 · 2022: 86 · 2021: 70 · 2020: 25
- FWCI
- 10.25
- Type
- journal article
- Language
- en
- Open access
- diamond
- doi.org
- Licence
- Locations
- Pulmonology (publishedVersion, cc-by-nc-nd)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
- eScholarship (California Digital Library) (submittedVersion)
- eScholarship (California Digital Library) (submittedVersion, cc-by-nc-nd)
- Topics
- Physical Sciences › Mathematics › Modeling and Simulation › COVID-19 epidemiological studies
- Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 detection and testing
- Health Sciences › Medicine › Infectious Diseases › COVID-19 Clinical Research Studies
- Keywords
- COVID-19 pandemic, underreporting of cases, under-detection, case fatality rate, COVID-19 mortality, diagnostic testing capacity, fold change, cross-national comparison, health infrastructure, containment measures
- MeSH terms
- COVID-19, SARS-CoV-2, COVID-19 Testing, Humans, World Health Organization, Internationality
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