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COVID-19 | School of Public Health Expert Insights


School of Public Health Expert Insights

Coronavirus Questions and Answers

Public Health On Call

In the March 14 episode of the Public Health On Call podcast, Josh Sharfstein gets more answers from Dr. Tom Inglesby of the Johns Hopkins Center for Health Security.

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By Joshua Sharfstein, M.D.
Johns Hopkins Bloomberg School of Public Health
Vice Dean for Public Health Practice and Community Engagement and Professor of the Practice
Host, Public Health on Call

These questions and answers were posted on March 14, 2020. Given the evolving circumstances around COVID-19, some of the recommendations may have changed since that time. Please keep this possibility in mind, and visit the resources listed in the answer to the first question below for the most up-to-date information.

How To Keep Informed

What are good sources of information?

The Centers for Disease Control and Prevention website on COVID-19 is here, including links to many important guidance documents for different audiences. The CDC FAQ document is here.

The comprehensive Johns Hopkins website is with links to an up-to-date case tracker (including global, country- and state-specific information), a daily situation report, and other tools and resources.

Where can I hear from some experts in the coronavirus directly?

The Johns Hopkins Bloomberg School of Public Health also hosts a daily podcast called Public Health On Call featuring interviews with experts and others on the front lines.

Social Distancing

What does social distancing mean?

Social distancing means reducing social interaction to reduce the chance a contagious disease spreads. Examples include teleworking, avoiding large gatherings, and staying home when sick. At this time, the Centers for Disease Control and Prevention and other public health agencies are recommending early adoption of social distancing in order to reduce the spread of the new coronavirus. Reducing the spread reduces the number of people sick at any one time, which is important to preventing the health care system from becoming overwhelmed with patients.

Should everyone be practicing social distancing or just certain people?

Everyone. People at highest risk of serious illness—such as older adults and people with chronic illness—should be especially vigilant about social distancing, changing their usual routines to protect the health of themselves and others.


Is it safe to send my kids to school?

Generally speaking, it is safe for children to attend school. The coronavirus appears to be much less likely to make kids seriously ill compared to older adults.

At the same time, some communities have closed or are considering closing schools to reduce spread of the novel coronavirus in the community as a whole.

Should schools be closed to protect the community?

The main goal of school closures would be to slow the spread of disease in a community so that hospitals are less likely to be overwhelmed by too many critically ill patients at one time.

Based on the success of social distancing policies, including school closures, in Asian settings, there is a good argument for closing schools in the U.S. A study from Shenzen, China found that young people are getting infected by the virus even though many show no symptoms of infection.

But there are serious potential downsides to school closures that will need to be addressed when or if school closures are put into place. Many kids in the US depend on schools for meals, so meals will need to be provided by an alternative means. Other downsides include the academic loss for students, and the fact that students with special needs may be at much greater risk without access to their usual resources in school.

Where schools are shut down, it’s important not to recreate the same risks of transmission in other settings, such as day camps. Such a risk may be mitigated by very clear instructions to families and students about the reasoning behind and the life-and-death stakes of this policy.

Other challenges include: Having kids at home might also prevent parents from working; this is a special challenge for parents who are first responders or who work in the health care system. And elderly family members who aren’t otherwise in the same household of a student but are asked to provide childcare might also be at risk.

Where schools are closed, these problems will need to be addressed.

How will schools decide if and when to close?

These will be state and local decisions.

Treatment and Care

Why are people over 60 more at risk?

The answer is not fully known, but it turns out all coronaviruses (including SARS and MERS) affect older adults more.

How should I help a friend, neighbor or family member who is ill?

If they are ill from coronavirus, you can drop off food or other supplies for them, call them, and make sure they’re coping well. If they are getting sicker, you can help them notify their doctor or local public health agency to arrange for medical care.

Will I get sick if I help care for them?

If you’re caring for them directly without adequate protective equipment, the chance of infection is very high. If people need that extra care, they may need to be hospitalized.

How are vaccines and medications being developed?

Some medications are already in clinical trials with early results that may be reported as soon as the next few weeks. The vaccines will take longer to develop and distribute —it’s been estimated 18 months to 2 years, and that’s assuming the trials show the vaccine works.


What masks are necessary and when?

Members of the general public should not wear masks if they are healthy. The masks can actually contribute to infection because people touch their faces to adjust the masks.

Outside of the health care setting, masks are recommended for people already with illness to reduce the chance they spread the disease to family members or others.

In health care, masks are part of personal protective equipment (PPE) for health care workers to ensure that nurses, doctors and others remain healthy and able to care for sick patients.

Can people who have no symptoms transmit the virus?

Yes. It’s not known how much this contributes to spread, but there is evidence that transmission prior to the development of symptoms occurs.

Can pets get the disease?

There are reports of a dog that showed some symptoms, but nothing serious.


Why might a public health agency ask people to quarantine?

Quarantine refers to control of the movement of people who are exposed to an illness, but not yet infected. The purpose is to reduce the chance they will get the disease and then pass it on to other people.

What does quarantine entail?

Generally, public health officials are asking people with known exposure to “self-quarantine,” which means to stay at home for 14 days, minimizing contact with others.

Why is it 14 days?

Because evidence has demonstrated that nearly everyone who falls ill with coronavirus infection (known as COVID-19) after an exposure to the virus falls ill within 14 days.

If you are tested and the test is negative, do you still have to be quarantined?

Yes. The reason is the test measures infection, not exposure. Someone can be exposed on a Monday, not develop an infection yet on a Tuesday and test negative, but then develop a clinical infection on Wednesday and then have a positive test Thursday. So, quarantine needs to last for 14 days regardless of testing results.

If you and somebody else are quarantined as a result of an exposure to someone with COVID-19, can you quarantine together?

No, this is not recommended.

What about families in which one person has been exposed, but others have not?

People who are asked to quarantine as a result of exposure to someone known to have COVID-19 should not be quarantined with others who have not had such exposure. This may be challenging within a home, where people are advised to use separate bedrooms and bathrooms.


When is testing important?

Testing is particularly important for people who are seriously ill. Knowing the diagnosis is important for clinical care, allows health care workers to protect themselves, and is necessary for research into treatments.

For people who are mildly or moderately ill, testing can help assure that they isolate themselves and alert contacts of the potential need for quarantine. By quickly identifying individuals who are sick and isolating them, public health authorities can reduce the spread of the novel coronavirus.

To assure both that tests are available for those who need them and that the health professionals are prepared to do the test safely, adequate safety equipment is essential. Not every clinic or medical office will conduct the testing. Physicians and public health authorities should direct people to where they can be tested.

Given the limited availability of testing, there is much less urgency to test people who are feeling well.

Also, wherever possible, people should not just show up at emergency departments for testing, in order to reduce the demand on hospitals, as well as to protect themselves and others. It is much better to call ahead, determine that testing is appropriate available, and follow instructions on where and when to go.

Why are we only using CDC tests?

We are no longer using only CDC tests. Two large national private lab providers—LabCorp and Quest Diagnostics—are now able to conduct the testing, as are a number of health systems.

Why are we having problems getting tests out?

There are many reasons that testing has not been widely available. An explanation is here.

Why are there reagent shortages that are impacting testing?

It is unclear why these shortages are occurring, but there appears to be a lack of critical supplies needed to deploy the current tests. Addressing these potential shortages and preventing other potential issues that may limit access are urgent priorities.


Should I avoid travel to places affected by the outbreak?

Yes, if possible. The CDC recommends that people avoid all nonessential travel to countries with widespread and ongoing transmission of the novel coronavirus. For the latest recommendations, please consult its website.

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