Why Some COVID-19 Cases Are Worse than Others

Emerging data as well as knowledge from the SARS and MERS coronavirus outbreaks yield some clues as to why SARS-CoV-2 affects some people worse than others.

Written byKatarina Zimmer
| 7 min read

Register for free to listen to this article
Listen with Speechify
0:00
7:00
Share

ABOVE: Colored visualization of electron microscopy photo of the coronavirus SARS-CoV-2
© ISTOCK.COM, NARVIKK

Like many other respiratory conditions, COVID-19—the disease caused by SARS-CoV-2—can vary widely among patients. The vast majority of confirmed cases are considered mild, involving mostly cold-like symptoms to mild pneumonia, according to the latest and largest set of data on the new coronavirus outbreak released February 17 by the Chinese Center for Disease Control and Prevention.

Fourteen percent of confirmed cases have been “severe,” involving serious pneumonia and shortness of breath. Another 5 percent of patients confirmed to have the disease developed respiratory failure, septic shock, and/or multi-organ failure—what the agency calls “critical cases” potentially resulting in death. Roughly 2.3 percent of confirmed cases did result in death.

Scientists are working to understand why some people suffer more from the virus than others. It is also unclear why the new coronavirus—like its cousins SARS and MERS—appears to ...

Interested in reading more?

Become a Member of

The Scientist Logo
Receive full access to more than 35 years of archives, as well as TS Digest, digital editions of The Scientist, feature stories, and much more!
Already a member? Login Here

Related Topics

Meet the Author

  • katya katarina zimmer

    After a year teaching an algorithm to differentiate between the echolocation calls of different bat species, Katarina decided she was simply too greedy to focus on one field of science and wanted to write about all of them. Following an internship with The Scientist in 2017, she’s been happily freelancing for a number of publications, covering everything from climate change to oncology. Katarina is a news correspondent for The Scientist and contributes occasional features to the magazine. Find her on Twitter @katarinazimmer and read her work on her website.

    View Full Profile
Share
Image of a woman with her hands across her stomach. She has a look of discomfort on her face. There is a blown up image of her stomach next to her and it has colorful butterflies and gut bacteria all swarming within the gut.
November 2025, Issue 1

Why Do We Feel Butterflies in the Stomach?

These fluttering sensations are the brain’s reaction to certain emotions, which can be amplified or soothed by the gut’s own “bugs".

View this Issue
Olga Anczukow and Ryan Englander discuss how transcriptome splicing affects immune system function in lung cancer.

Long-Read RNA Sequencing Reveals a Regulatory Role for Splicing in Immunotherapy Responses

Pacific Biosciences logo
Research Roundtable: The Evolving World of Spatial Biology

Research Roundtable: The Evolving World of Spatial Biology

Conceptual cartoon image of gene editing technology

Exploring the State of the Art in Gene Editing Techniques

Bio-Rad
Conceptual image of a doctor holding a brain puzzle, representing Alzheimer's disease diagnosis.

Simplifying Early Alzheimer’s Disease Diagnosis with Blood Testing

fujirebio logo

Products

Eppendorf Logo

Research on rewiring neural circuit in fruit flies wins 2025 Eppendorf & Science Prize

Evident Logo

EVIDENT's New FLUOVIEW FV5000 Redefines the Boundaries of Confocal and Multiphoton Imaging

Evident Logo

EVIDENT Launches Sixth Annual Image of the Year Contest

10x Genomics Logo

10x Genomics Launches the Next Generation of Chromium Flex to Empower Scientists to Massively Scale Single Cell Research