Studies have shown that even though asymptomatic people have the same viral load, they have increased levels of lymphocytes (CD4+cells) as compared to symptomatic people, which may lead to them being asymptomatic. Due to the presence of increased lymphocytes, they also clear the viral particles faster and show lower risk of long term complications. 



State University of New York at Buffalo

Several studies have shown that COVID-19 can be transmitted by individuals who do not show any symptoms, or who are "asymptomatic". Because asymptomatic individuals are not routinely tested, the prevalence of asymptomatic infection is not well-defined.

Asymptomatic COVID-19 Infection

Previous reports indicate that asymptomatic transmission is possible, but since they’re hard to track, this poses a significant challenge to infection control practices.

Implications of Asymptomatic COVID-19 Transmission

- China
- Germany
- Japan
- USA
- Singapore

Asymptomatic COVID-19 Infection Categorized by Country

- Travel Medicine and Infectious Diseases References
-Science China Life Sciences
-Journal of American Medical Association (JAMA)
- New England Journal of Medicine (NEJM)
- Euro Surveillance
- Morbidity and Mortality Weekly Report (MMWR)
- Nature Medicine

Asymptomatic COVID-19 Infection References by Journal

- Viral shedding
- IgG levels
- Low white blood cell count (lymphopenia)
- Low blood platelet count (thrombocytopenia)
- Chest CT focal ground-glass opacities
- Chest CT stripe shadows

Clinical and Immunological Results of Asymptomatic COVID-19 Infection

Due to the SARS-CoV-2 viral load being similar between asymptomatic and symptomatic healthcare workers with COVID-19, asymptomatic healthcare workers donning less PPE may be a risk factor for other colleagues, patients, and the community.

Healthcare Workers with Asymptomatic COVID-19 Infection

In addition to symptomatic screening, additional control/detection methods are routine rRT-PCR testing, conservative guidelines for reopening, and periodic testing are important for epidemiological evaluations. Facilities using these methods include nursing homes and other congregate living situations such as prisons, mental health facilities, and homeless shelters.

Additional control/detection methods to prevent asymptomatic transmission

- Fever (when high temperature is measured)
- Laboratory confirmation of illness via viral testing
- Radiological lung abnormalities such as ground-glass chest and stripe shadowing


Learn Before

Related