An overview of illnesses seen in people with COVID-19

The Chinese Center for Disease Control and Prevention (CDC) has published the largest analysis to date of people with COVID-19. Here is a summary of its findings, based on data collected between December 2019 and February 2020.

Information from a total of 72,314 cases was analyzed. The breakdown of the cases as defined by the Chinese CDC is as follows:

  • 44,672 people had SARS-CoV-2 confirmed by RNA testing
  • 16,186 people were diagnosed with COVID-19 based on symptoms and exposure; they could not be tested for infection with SARS-CoV-2 infection due to a shortage of tests
  • 10,567 people were diagnosed with COVID-19 based on symptoms, exposure to people already diagnosed with COVID-19 and CT scans suggestive of coronavirus pneumonia; no RNA testing for SARS-CoV-2 was performed
  • 889 people tested positive for SARS-CoV-2 but were free from symptoms associated with the virus


Most people in the analysis were between the ages of 30 and 79 years. The Chinese CDC provided the following age distribution of the 44,672 confirmed cases:

  • 1% of people were younger than 10 years old
  • 1% of people were aged 10 to 19 years
  • 8% of people were aged 20 to 29 years
  • 87% of people were aged 30 to 79 years
  • 3% of people were aged 80 and older

The spectrum of disease among 44,415 people was as follows:

  • 81% of people had what the Chinese CDC called mild symptoms – no pneumonia or, at worst, mild pneumonia
  • 14% of people had more severe issues – shortness of breath, rapid breathing, less-than-normal levels of oxygen in their blood, rapid development of lung injury
  • 5% of people were in a critical state – their vital organs were failing and they required invasive ventilation


Among 46,672 confirmed cases of COVID-19, overall, 2.3% of people died. The distribution of deaths by age was as follows:

  • 80 years and older – 15%
  • 70 to 79 years – 8%

(No further age distribution for adults was provided.)

No deaths occurred in mild or severe cases, only in critical cases. The scientists further stated that no deaths occurred among children aged 9 years and younger.

Underlying conditions and death

The distribution of deaths in people who had certain underlying conditions prior to the development of COVID-19 was as follows:

  • cardiovascular disease – 11%
  • diabetes – 7.3%
  • chronic respiratory disease – 6.3%
  • higher-than-normal blood pressure – 6%
  • cancer – 6%

The issue of underlying diseases and its connection to severe COVID-19 has puzzled doctors. Later in this issue of TreatmentUpdate we revisit underlying issues and theories about why they make some people more susceptible to severe illness with COVID-19.

—Sean R. Hosein


Wu Z, McGoogan JM. Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China: Summary of a report of 72,314 cases from the Chinese Center for Disease Control and Prevention. JAMA. 2020; 323(13):1239-1242.