COVID-19 Fast Facts

Summarized from Fitzgerald Health Education Associates

How a virus with a reproduction number (R0) of 2 spreads

Transmission R0 (pronounced “R naught”), or basic reproduction number, refers to the average number of cases an infected person will cause during their infectious period and reflects how contagious a disease is.

• R0 value for SARS-COV-2 = 2.2. A single infected person will infect about 2.2 others, on average.[1]

• R0 value for typical seasonal influenza = 1.3

• R0 value for SARS-COV (2002-2003) = 3.02 [2]

• R0 value of 1918 swine flu pandemic = 1.4–2.83 [3]

R0 describes how many cases of a disease an infected person will go on to cause – in this imagined scenario R0=2.The Conversation,CC BY-ND

COVID-19 Estimated incubation time [4]

• Median = 5.1 days

• Mean = 5.5 days

COVID-19 Time to symptoms [4]

• Median time to fever onset = 5.7 days

• Fever onset in nearly all (97.5%) by 12.5 days

• Fever onset in <2.5% by 2.2 days

COVID-19 Symptomatic infections missed over course of active monitoring program [4]

• With 7-day monitoring/home isolation after exposure, 21.2 symptomatic infections would be missed per 10,000 persons who have had a high-risk exposure, risking transmission when coming off home isolation.

• With 14-day monitoring/home isolation after exposure, 1.0 symptomatic infections would be missed per 10,000 persons who have had a high-risk exposure when coming off home isolation.

COVID-19 Features in Adults [5]

Common, especially with disease onset

• Fever: 85%–90%

• Cough: 65%–70%

• Fatigue: 35%–40%

• Sputum production: 30%–35%

• Shortness of breath: 15%–20%

COVID-19 Features in Children [6]

Diagnosis

• Asymptomatic infection: 15.8%

• Upper respiratory tract infection: 19.3%

• Pneumonia: 64.9%

Symptoms/signs

• Cough: 48.5%

• Pharyngeal erythema: 46.2%

• Fever: 41.5%

CT chest abnormalities

• Ground-glass opacity: 32.7%

References

1. Bates Ramirez V. What is R0?: gauging contagious infections. Healthline website. www.healthline.com/health/r-noughtreproduction-number#calculation. Accessed March 27, 2020.

2. Cascella M, Rajnik M, Cuomo A, et al. Features, evaluation and treatment coronavirus (COVID-19). StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020. 2020 Mar 20. www.ncbi.nlm.nih.gov/books/NBK554776/. Accessed March 27, 2020.

3. Eisernberg J. How scientists quantify the intensity of an outbreak like COVID-19. The Conversation website. https://theconversation.com/r0-how-scientists-quantify-the-intensity-of-anoutbreak-like-coronavirus-and-predict-the-pandemics-spread130777. Accessed March 27, 2020.

4. Lauer SA, Grantz KY, Bi Q, et al. The incubation period of coronavirus disease 2019 (COVID-19) from publicly reported confirmed cases: estimation and application. Ann Intern Med. 10 March 2020. DOI: 10.7326/M20-0504

5. Bell DJ. COVID-19. Radiopaedia website. https://radiopaedia.org/articles/covid-19-3?lang=us#nav_clinical-presentation. Accessed March 29, 2020.

6. Lu X, Zhang L, Du H, et al. SARS-CoV-2 infection in children. N Engl J Med. Mar 18 2020. DOI: 10.1056/NEJMc2005073.