The information we have about COVID-19 is always evolving.
New variants may be more contagious than the current dominant strains.
This article looks at what we know about the contagiousness of COVID-19.
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What This Means For You
COVID-19 is a very contagious disease.
Knowing how the SARS-CoV-2 virus spreads and how long it stays in your system is important.
This can help reduce your likelihood of catching COVID-19 or passing it to a loved one.
How Does COVID-19 Spread?
According to the World Health Organization (WHO), the primary way COVID-19 spreads is through respiratory droplets.
These are small particles that stay in the air after a person sneezes, coughs, or speaks.
The virus can also spread when you touch a contaminated surface or object.
Research suggests that most of the spread happens at close range, within about 6 feet.
There is also evidence that particles can travel longer distances in the air.
In certain circumstances, these airborne particles may also transmit SARS-CoV-2.
These means the virus may spread more easily in places with poor ventilation.
How Long Are People Contagious?
Symptom onset is the day you first start to feel sick.
People who have had severe COVID-19 may be contagious for up to 20 days.
This is also true for people who areimmunocompromised.
Immunocompromised people have immune systems that don’t function well.
Self-isolate as soon as you have tested positive for COVID-19 or start having symptoms.
This means staying home.
If possible, infected people should sleep in a separate bedroom.
If you have COVID-19, use a separate bathroom and wipe down common surfaces.
Everyone in the house should make a run at limit their exposure.
As much as possible, household members who are not sick should avoid interactions with people outside the home.
COVID-19 is very contagious.
it’s possible for you to pass it to others even if you have mild or no symptoms.
It is important to self-isolate as soon as you start to feel sick.
When Are People Most Contagious?
A 2020 study looked at COVID-19 transmission among 100 confirmed patients and their contacts in Taiwan.
People with COVID-19 can beasymptomaticorpre-symptomatic.
An asymptomatic person is infected with SARS-CoV-2 but has no symptoms.
A pre-symptomatic person is infected but isn’t showing symptomsyet.
This is one reason why it is so difficult to stop the spread of COVID-19.
If you don’t have symptoms, you may not know you have COVID-19.
Sometimes the only way to know is to get tested.
This is why it’s important to get tested if you’ve been exposed to someone with COVID-19.
Is COVID-19 Getting More Contagious?
The SARS-CoV-2 virus mutates over time.
The delta variant is more contagious than the original form of SARS-CoV-2.
This is because it is associated with higher viral load.
Viral load is the amount of virus that’s in your body.
A person with a higher viral load is more contagious.
New variants may also prove to be more contagious.
This does not necessarily mean they will be more severe.
Do People Who Have Been Around Someone With COVID-19 Need to Self-Quarantine?
The short answer is yes.
COVID-19 is highly contagious.
If you are fully vaccinated, you still need to be careful.
Get a COVID-19 test five to seven days after your last contact with the infected person.
You also do not need to stay home if you had COVID-19 within the previous three monthsandhave recoveredandare symptom-free.
Community and close contact exposures are still the main drivers of COVID-19.
Transmission is most likely indoors.
Workplaces with lots of people who spend many hours together have high rates of transmission.
Transmission is also high within households.
A PCR test looks for the genetic material of the SARS CoV-2 virus.
The CDC no longer requires this test.
Are Clinically Recovered People Still Contagious?
Sometimes, people will continue to test positive for COVID-19 for weeks after they no longer have symptoms.
Health experts still dont know why.
The CDC says these people are unlikely to be contagious.
Studies have not found any evidence that people who have recovered from COVID-19 can pass it on to others.
For the most recent updates on COVID-19, visit ourcoronavirus news page.
World Health Organization.Coronavirus disease (COVID-19): How is it transmitted?
OKeeffe J, Eykelbosh A.
National Collaborating Centre for Environmental Health.Understanding transmission of SARS-CoV-2 in the ongoing COVID-19 pandemic.
Centers for Disease Control and Prevention.Ending isolation and precautions for people with COVID-19: interim guidance.
