I Have to Quarantine for How Long? And Other COVID-19 Questions Answered
In this Q&A, we speak with epidemiologist Kelly Kamm about virus latency, isolation
versus quarantine, contact tracing, and why medical guidelines continue to change.
Kelly Kamm is an epidemiologist and assistant professor of kinesiology and integrative
physiology at Michigan Technological University. Kamm’s expertise has been vital to
informing the University’s response to the COVID-19 pandemic. Here, she explains some
of the more complicated aspects of COVID-19 in a college setting.
Want to Learn More about COVID-19? You’re Invited!
Steven Elmer and Kelly Kamm — faculty in Michigan Tech’s Kinesiology and Integrated
Physiology Department — along with the Health Research Institute, are teaching a COVID-19 course this semester. To increase community engagement and
knowledge, Elmer and Kamm will host a Zoom town hall series as a component in the
course. Community members are invited to the Zoom gatherings, which will be held Thursdays
from 7 to 8 p.m. and broadcast on 97.7 The Wolf (WOLV-FM). The first town hall will be Thursday, Sept. 3, and sessions will continue weekly until Dec. 3.
How Long Am I Contagious?
Q: What is the latency period of the SARS-CoV-2 virus, which causes COVID-19?
KK: The virus can take between two and 14 days for someone to develop symptoms or
test positive from the time they are exposed. This is called the incubation period.
Many factors impact the range of the incubation period. If you were exposed on Monday
the 1st and had a COVID-19 test on the 5th, only about half the people who are infected
will have a positive test or have symptoms at that time. Just because you test negative
on day five does not mean that you are not infected; you could still test positive
up to 14 days after the exposure.
What’s the Difference Between Isolation and Quarantine?
Q: How does the incubation period relate to how long a person needs to isolate or quarantine?
KK: If someone tests positive for the virus — whether or not they have symptoms —
they are infected and must be isolated. Their time in separation is based on the infectious
period, which is how long they are able to spread the disease to other people. The
infectious period differs between individuals, but can be determined based on their
symptoms and whether those symptoms are resolving, or a specified time period if they
tested positive but never develop any symptoms.
Q: So, what’s the minimum a person would need to isolate if they have no symptoms?
KK: If they test positive, but have no symptoms, they will be under isolation for
a minimum of 10 days. If they develop symptoms anywhere in that 10 days, how long
they stay in isolation depends on resolution of symptoms.
Q: Are you saying that a person can be infectious to others as long as they have symptoms?
KK: Yes. The length of the infectious period due to the virus has a lot to do with
the individual and their particular disease journey. Someone with a severe case will
have a much longer infectious period than someone with a mild case.
Current Centers for Disease Control [and Prevention] guidance is that a fever has
to be entirely resolved for at least 24 hours with no medication to bring it down.
Other symptoms (cough, loss of sense of smell, sore throat, shortness of breath) have
to be improving and it must be at least 10 days since symptoms began.
The shortest time period of separation is 10 days if there are minimal or no symptoms,
but the isolation period can be much longer than that in severe cases.
Q: How is quarantine different from isolation, then?
KK: We quarantine people who have been exposed but we don’t yet know if they are infected
or not. Someone with COVID-19 is infectious for one to three days before they experience
symptoms. The quarantine is meant to prevent someone who is infected from spreading
the disease during that period when they are infectious but do not know it. Because
people can become positive for the virus anytime during a 14-day period after exposure,
it is important to stay separated from others for that full quarantine period.
However, if you have multiple people in a household, you can be in quarantine a long
If one of your roommates tests positive and you cannot completely separate yourself
from this roommate, you are continuously exposed to that roommate. That means that
your last exposure, and day one of your 14-day quarantine, begins on the last day
your roommate is infectious. So, if your roommate recovers after 10 days, your separation
from other people includes the 10 days your roommate was infectious plus an additional
14 days (24 days total).
If one of your roommates tests positive but you are able to fully separate that roommate
from the rest of the house, your quarantine starts the day your roommate was isolated
from you. But if a second roommate tests positive on day 10 of your quarantine period,
your quarantine will reset because you have a new exposure. Every time you have a
new exposure to someone with COVID-19, your quarantine restarts, and you will need
to be in quarantine 14 days after your last exposure.
Q: If you do live with multiple roommates or family members and someone in the house
is in isolation, can you share bathrooms or other living spaces as long as you’re
not in the same room at the same time?
KK: No. The person in isolation must have their own bedroom and stay in that room.
It is best if they have a separate bathroom, but if that is not possible, there are
strict disinfection and use guidelines that must be followed. Meals should be left
outside the individual’s bedroom and no one else should use those dishes. You must
remain totally separate.
How Does the Virus Spread?
Q: Wow, that’s intense. But I thought as long as you remain six feet away and aren’t
in the same room for longer than 15 minutes, you won’t catch the virus.
KK: Six feet apart for no more than 15 minutes in an enclosed space is not a hard
and fast rule. It’s a good estimator, but not foolproof.
How Does the Virus Live on Surfaces?
Learn more about virus surface chemistry in this short video.
The novel coronavirus is typically passed to others through airborne spread. If you
sneeze or cough or droplets are formed when you’re talking or breathing hard, those
droplets travel through the air. If they come into contact with the nose, mouth or
eyes of someone who is susceptible, that is a route of entry.
The closer you are to that someone, and the longer you stay there, the more likely
it is for this to happen.
Another way you can catch the virus is through indirect contact. If someone coughs
into their hand and touches a doorknob, they may leave virus particles on that doorknob.
If you touch that doorknob and then touch your eyes, nose or mouth, the virus can
enter your body.
The key to preventing indirect spread is to wash your hands immediately after you
touch things other people touch. Make sure to cough into your elbow, not your hands.
Don’t touch your face until you wash your hands.
How Does Contact Tracing Work?
Q: Michigan Tech is hiring people to work as contact tracers to make sure people who
may have been exposed can quarantine themselves to keep the virus from spreading.
How are you involved in contact tracing?
KK: I am helping recruit, train, and manage a team of student volunteers who will
help the Western Upper Peninsula Health Department by conducting contact tracing in
our campus community.
About the Researcher
Q: I’m happy to report that at least 100 people have answered the call to become contact
tracers. But how many do you need?
KK: It is very difficult to estimate how much time or how many tracers we need. So
many variables go into the time it takes to trace contacts.
Q: What do the contact tracers do?
KK: When someone tests positive for COVID-19, the health department calls them and
interviews them. The health department official asks about who the positive case might
have been around during their infectious period to identify who meets the threshold
level of a close contact who needs to be quarantined. The general definition of a
close contact is someone within six feet of an infected person during the infectious
period for at least 15 minutes.
Contact tracers work to notify the close contacts of the need to quarantine and help
connect those in quarantine with Michigan Tech and community resources they may need.
If you think you may be a close contact, call the health department and they can help
you determine if you were. The health department notifies us if close contacts include
people from the campus community. Our campus team is also able to identify people
who report they are a close contact through the Daily Symptom Tracker.
It’s really important to answer your phone or listen to your phone messages. This
method to stop the spread of COVID-19 works best when a close contact is placed under
quarantine as soon after the exposure as possible.
Information shared with the contact tracing team is confidential. We do leave messages
and there is a way to call us back or we will keep trying. If you are called by a
contact tracer, the phone number will come up as an MTU number with a 487 prefix.
Why Does the Science Keep Changing?
Q: Unfortunately, a lot of people are mistrustful of scientists and medical researchers
right now. There’s a lot of misinformation out there. Why do medical and scientific
guidelines keep changing?
KK: This is a brand-new disease, so everything we are learning is new. We are working
to understand not only the virus itself, but also what public health measures work
and don’t work.
This is a coronavirus and scientists based a lot of the early information on SARS
and MERS [coronaviruses that caused small outbreaks in 2003 and 2012, respectively],
yet they are still very different viruses. We are continually refining and adjusting
what we know as more data is available.
Q: To use a metaphor, coronaviruses could be compared to dog breeds. SARS-CoV-2 is
a wolfhound, whereas MERS is a rottweiler. They’re both dogs, but they’re very different.
KK: Exactly. When you have something so new, you have to build up the scientific knowledge
base. What’s been said in the past that may be different now is not misinformation
— it’s that we’ve learned more. It makes it very hard to understand because advice
does, necessarily so, change.
For example, I can’t estimate how many contact tracers I need because I don’t know
how many contacts a college student might have. We can use the information as we learn
it to build on in the future.
In this age of, “If I can’t get it in two seconds, it’s so slow,” we must remember
that science takes time. Public health is a science.
Q: How long do you think it will be until there’s a vaccine?
KK: The shortest time to get a vaccine has been four years; the average is 10 to 15
years. The fact that we think we might have a vaccine in just a year is scientifically
Scientists mapped the entire genome of the virus within a month from when it was identified.
It’s amazing to look at how much we do know about this virus in such a short period.
Michigan Technological University is a public research university, home to more than
7,000 students from 54 countries. Founded in 1885, the University offers more than
120 undergraduate and graduate degree programs in science and technology, engineering,
forestry, business and economics, health professions, humanities, mathematics, and
social sciences. Our campus in Michigan’s Upper Peninsula overlooks the Keweenaw Waterway
and is just a few miles from Lake Superior.