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COVID-19 | School of Public Health Expert Insights


School of Public Health Expert Insights


July 21, 2021

I'm a Healthy Young Person. Why Should I Get a COVID Vaccine?

Even healthy, young people should get vaccinated. Here’s why.

July 20, 2021

What We Do and Don’t Know About Long COVID and Long-Haulers

Up to a year after having COVID-19, some people have yet to fully recover.

July 16, 2021

Carrying Equity in COVID-19 Vaccination Forward: Guidance Informed by Communities of Color

A new report from CommuniVax provides recommendations to better serve groups with persistently low vaccine coverage.

July 15, 2021

The Tokyo Olympics and COVID-19

A public health expert and Olympic silver medalist’s take on the safety of the Tokyo Olympics.

July 14, 2021

COVID-19 Vaccines and Immunocompromised People: Fully Vaccinated and Not Protected

Only 50% of people who are immunocompromised show an antibody response to COVID-19 after vaccination.

July 8, 2021

What the Delta Variant Means for Vaccinated and Unvaccinated People

The delta variant is cause for concern from a global health standpoint.

July 1, 2021

COVID-19 and Fungi: A Nightmare in the Making

India’s “black fungus” crisis stands to far outlive the latest wave of COVID-19—in the form of a chronic fungal disease that kills slowly and is extraordinarily difficult to treat.

June 21, 2021

Should I Ask My Friends If They Are Vaccinated?

Guidance for individuals and families navigating a half-vaxxed life.

June 17, 2021

Will There Be a Fall 2021 Resurgence of COVID-19 in the U.S.?

The future of the pandemic depends a lot on what we do this summer.

June 10, 2021

The Impacts of COVID-19 on Diabetes and Insulin

Hoarding and rationing insulin has become a normality for many type 1 diabetics in the US—a reality exacerbated by the COVID-19 pandemic.

June 8, 2021

The COVID-19 Questions We Don’t Have Answers For Yet

There’s still a lot we don’t know about COVID-19.

May 28, 2021

Why COVID-19 Vaccines Offer Better Protection Than Infection

Vaccination offers longer, stronger immunity, says virologist Sabra Klein.

May 28, 2021

COVID-19 Testing Update

Even with vaccination rates on the rise, testing remains a valuable tool to track variants and stem outbreaks.

May 17, 2021

Teen Mental Health During COVID-19

Disrupting school and interactions with peers, the pandemic has left teens with stress, anxiety, and other mental health challenges.

May 10, 2021

WTO TRIPS Waiver for COVID-19 Vaccines

Understanding the “TRIPS waiver” of intellectual property protections related to COVID vaccines.

May 6, 2021

How Can I Talk to My Friends and Family About Getting Vaccinated for COVID-19?

It’s fair for people to have questions about COVID-19 vaccines. Fortunately, there are answers.

April 20, 2021

The Environmental Toll of Fighting COVID-19

Masks, gloves, and chemical disinfectants will outlast the pandemic.

April 15, 2021

What to Make of Vaccine Pauses

A cautious, transparent response reveals a process committed to vaccine safety.

April 8, 2021

New Data on COVID-19 Transmission by Vaccinated Individuals

New data indicate that COVID-19 vaccines stop symptomatic COVID and make it highly unlikely that someone can be infected at all.

April 6, 2021

What is Herd Immunity and How Can We Achieve it With COVID-19?

Stopping SARS-CoV-2 will require a substantial percentage of the population to be immune. How can we get to that point?

April 1, 2021

Outbreak, Interrupted: Why Testing Is Important for K-12 Schools

Combined with masking, proper ventilation, and vaccinating teachers, COVID tests can help keep K-12 schools safe for everyone.

March 31, 2021

COVID-19 Continues to Highlight Gaps in Accessibility for People with Disabilities

Bonnielin Swenor gives an update on the continued gaps in accessibility for people with disabilities during the pandemic.

March 30, 2021

Ending the Pandemic and Vaccine Resistance: Modern Questions, Long History

Two historians discuss how the COVID pandemic might end, what history can tell us about vaccine hesitancy, and more.

March 29, 2021

COVID-19 Vaccines and Pregnancy

The ethics and safety of COVID-19 vaccines for pregnant people.

March 24, 2021

Meeting COVID-19 Misinformation and Disinformation Head-On

Mis- and disinformation should be elevated to and addressed as risks to national security.

March 24, 2021

More Questions and Answers About COVID-19 Vaccines

Josh Sharfstein answers a list of important questions about the COVID-19 vaccine.

March 19, 2021

When Will Children Be Vaccinated Against COVID-19?

Why are children not eligible for COVID-19 vaccines? Is it safe for unvaccinated children to go to school? Kawsar Talaat answers these questions and more.

March 9, 2021

What You Need to Know About the CDC’s COVID-19 Guidance for Fully Vaccinated Individuals

Understanding the CDC’s guidance for individuals fully vaccinated for COVID-19

March 4, 2021

Is It Safe to Reopen U.S. Schools During the COVID-19 Pandemic?

When a COVID-19 vaccine is available, an allocation plan will be needed, which means prioritizing certain groups.

March 4, 2021

Equity in Vaccination: A Plan to Work with Communities of Color Toward COVID-19 Recovery and Beyond

True recovery from the pandemic will require mending broken systems and innovation to address generations-old inequity.

March 1, 2021

What You Need to Know About the Johnson & Johnson Vaccine

What you need to know about Johnson & Johnson’s nonreplicating viral vector vaccine for COVID-19.

February 12, 2021

Before COVID Comes Home: What You Can Do Now in Case Someone in Your Household Becomes Ill

With a slow vaccine rollout and sustained community transmission, it’s a good idea to prepare for the possibility of someone in your household getting COVID-19. 

February 12, 2021

What To Do If You Have COVID-19

If you have a confirmed COVID diagnosis via a positive test, there are a few things you can do immediately to protect both yourself and those around you.

February 9, 2021

The Ills of Pandemic Fatigue

While we may be feeling fatigued, it’s more important than ever to stay dedicated to public health practices.

February 2, 2021

Variants, Vaccines and What They Mean For COVID-19 Testing

As variants spread, do they complicate COVID-19 testing? And will vaccinations change the accuracy of diagnostic and antibody tests?

January 29, 2021

For mRNA Vaccines, COVID-19 Is Just the Beginning

Easy to manufacture and update, mRNA vaccines may be powerful tools against emerging variants and other infectious diseases.

January 22, 2021

Dating in the Time of COVID-19

The pandemic presents new constraints to people who want to date and meet new people—and also offers opportunities to quickly identify those with shared values.

January 15, 2021

The New Technology Behind COVID-19 RNA Vaccines and What This Means for Future Outbreaks

What sets RNA vaccine technology apart from more traditional methods? And how it could help with future outbreaks.

January 14, 2021

Your Questions About COVID-19, Answered

Frequently asked questions about COVID-19 answered by our experts.

January 13, 2021

COVID-19 and Stigma

Why shame and blame won’t help fight the pandemic, and what we should be focusing on instead

January 13, 2021

What You Need to Know About COVID-19 Variants

What we know right now about COVID-19 variants, mutations, and transmissibility, and what it means for guidance and vaccines.

January 7, 2021

Determining the Safety of COVID-19 Vaccines

While clinical trials are the gold standard to indicate if a vaccine’s benefits outweigh its risks, safety monitoring doesn’t stop there.

January 7, 2021

COVID-19 Vaccines: Verifying Safety and Identifying Misinformation

How do we know COVID-19 vaccines are safe?

December 17, 2020

Side Effects and COVID-19 Vaccines: What to Expect

It’s totally normal to experience side effects from COVID-19 vaccines. Here’s what you need to know.

December 10, 2020

How to Support Hospitals and Health Care Workers this Holiday Season 

The pandemic is at its worst, but don’t let disillusionment distract from the opportunity to help.

December 7, 2020

Overdispersion of COVID-19

Why 10%–20% of people with COVID-19 are responsible for a large share of the disease’s spread.

November 23, 2020

Clarifying COVID-19 Terminology

Efficacy vs. effectiveness, quarantine vs. isolation, and other often conflated terms in the COVID-19 lexicon. 

November 20, 2020

An Update on COVID-19 Treatments: Monoclonal Antibodies, Convalescent Plasma, and Other Promising Developments

Nearly a year into the pandemic, we’ve gotten better at clinically treating COVID.

November 17, 2020

Can COVID-19 Vaccines Be Mandatory in the U.S. and Who Decides?

Once COVID-19 vaccines are widely available, could they be made mandatory and, if so, what entities could enforce this?

November 16, 2020

How to “Reach In” to Meaningfully Connect with Loved Ones from Afar

“Reaching in” from afar is a great way to support the mental, emotional, and physical health of our loved ones when physically separated. 

November 13, 2020

Encouraging Early Results From Pfizer’s COVID-19 Vaccine and What Might Happen Next

Pfizer’s encouraging early results from Phase 3 of its COVID-19 vaccine clinical trials mean we could see a vaccine by early 2021.

November 10, 2020

How to Make Decisions About Winter Holiday Gatherings Amid COVID-19

Pandemic holiday planning—a guide to decision-making frameworks, best practices, and considerations for safe and healthy gatherings.

November 2, 2020

What Are All the Different Kinds of COVID-19 Tests?

Nasopharyngeal swabs, PCR tests, rapid tests, blood tests...what are the various COVID-19 tests and what are they looking for? An infectious diseases expert explains the current testing landscape.

October 29, 2020

Testing in K-12 Schools

Because children are often asymptomatic, symptom screenings and temperature checks alone are insufficient to prevent COVID-19 outbreaks in schools. Regular testing—when done strategically and alongside other efforts including masking and social distancing—can help.

October 20, 2020

What Is Emergency Use Authorization?

What exactly is emergency use authorization, how does it work, and can we trust it? Could we see EUAs for COVID-19 vaccines?

October 20, 2020

No, COVID-19 Is Not the Flu

A virologist breaks down key differences between COVID-19 and influenza to explain why this pandemic is so critically—and catastrophically—different.

October 15, 2020

COVID-19 and the U.S. Criminal Justice System: Evidence for Public Health Measures to Reduce the Risk of COVID-19

Evidence-based recommendations for protecting from COVID-19 all of the people who touch the criminal justice system, including incarcerated and detained people, staff, and jurors.

October 15, 2020

Innovative Holiday and Winter Gatherings in the Time of COVID-19

This pandemic will not be over any time soon. We need to figure out how to have enjoyable experiences with friends and family. Nothing is zero risk, but we can all make choices that minimize risk.

September 29, 2020

How Indoor Ventilation Systems Can Help Prevent or Permit the Spread of COVID-19

Outdoor interactions are safer when it comes to COVID-19, but what can be done to improve ventilation in buildings?

September 18, 2020

Coping with COVID-19’s Evolving Mental Health Toll

A psychologist offers tips for helping kids and adults deal with impacts of the ongoing pandemic.

September 15, 2020

COVID-19 in Jails, Prisons, and Immigration Detention Centers: A Q&A with Chris Beyrer

Successes and setbacks in protecting incarcerated people from COVID-19.

August 28, 2020

Florida, FEMA, and Fugate: Emergency Management Lessons from Hurricane Katrina for Conquering COVID

On the 15th anniversary of Hurricane Katrina, we remember Craig Fugate’s inspired leadership of the Florida Emergency Management Division’s post-Katrina response in Mississippi, which paved the way for his transformation of FEMA.

August 26, 2020

How Can I Ask My Friends to Wear Masks? Talking to Friends, Family, Kids, and Coworkers About COVID-19 Safety

Navigating the interpersonal side of COVID-19 safety.

August 24, 2020

Taking the Measure of Mental Health in a Pandemic

The disruptions from the COVID-19 pandemic are far from over.

August 19, 2020

Interim Framework for COVID-19 Vaccine Allocation in the United States

When a COVID-19 vaccine is available, an allocation plan will be needed, which means prioritizing certain groups.

August 14, 2020

The Important and Elusive Science Behind Safely Reopening Schools

The metrics that determine whether students learn in school or at home may differ, but the goal is the same: Maximize benefits, minimize harms.

August 14, 2020

Contact Tracing on Campus: What Universities Should Know Before Bringing Students Back

Campus life brings a risk for SARS-CoV-2 transmission. Colleges need to have a plan to minimize risk--and to act when transmission occurs.

August 12, 2020

COVID-19 and College Campuses: What You Need to Know

COVID-19 and college: Limiting the risk of COVID-19 transmission while engaging in academic and residential college life.

August 10, 2020

COVID-19 Testing: Understanding the “Percent Positive”

Two epidemiologists explain this important term and what it means for individuals and communities.

August 5, 2020

A Top Vaccine Expert Answers Important Questions About a COVID-19 Vaccine

The COVID-19 vaccine is on track to become the fastest-developed vaccine in history. That doesn’t mean the process is skipping any critical steps.

August 3, 2020

Resetting Our Response: Changes Needed in the US Approach to COVID-19

A new report from the Center for Health Security outlines ways the US needs to immediately reset its response to COVID-19.

July 31, 2020

Wearing a Mask Could Keep You from Getting Seriously Sick

Masks may protect you as well as those around you.

July 17, 2020

The Experiment that Proved Airborne Disease Transmission

As mounting evidence suggests that SARS-CoV-2 is airborne, we look back at the first controlled experiment that proved the airborne spread of respiratory disease—and at how those findings inform today’s COVID-19 response.

July 13, 2020

I Took the Johns Hopkins COVID-19 Contact Tracing Course. Now What?

For the thousands of people who completed and passed the assessment in the Johns Hopkins COVID-19 Contact Tracing course on Coursera, the next step might be finding opportunities to put these new skills to use in the pandemic.

July 9, 2020

Enhancing Public Trust and Health with COVID-19 Vaccination

There are significant considerations to be made in terms of how to vaccinate a global population. Chief among them will be addressing concerns about the vaccine itself—especially one produced on an accelerated timeline.

June 22, 2020

Transparency, Reproducibility, and Validation of COVID-19 Projection Models

Never in history have the public and media have been so acutely aware of the existence and importance of models for projecting infectious disease spread as in the wake of the COVID-19 pandemic.

June 18, 2020

Developing a National Strategy for Serosurveys in the United States

Serosurveys could help map COVID-19 prevalence. The Center for Health Security’s new report offers guidance for collecting data on a scale large enough to show “hot spots” or areas where community transmission may have abated.

June 17, 2020

Trust in Science and COVID-19

Public opinion findings reveal that distrust in science is a key factor in a polarized pandemic response.

June 15, 2020

Guiding Universities on the Path to Reopening

COVID-19 means higher education institutions are facing big questions about education and operation. The Center for Health Security has released a toolkit to help guide plans for safely reopening.

June 11, 2020

Re-opening? How families can reassess

People and families who took the message of “stay at home” seriously are wondering how we continue our role in protecting our loved ones while resuming some activities during the COVID-19 pandemic.

June 3, 2020

Hopeful Steps Forward in the Battle Against COVID-19

5 Bloomberg School department chairs discuss the progress made in a short time.

May 18, 2020

Home Visiting Programs Adapt to Connect with Vulnerable Families

COVID-19 is forcing home visitors to maintain relationships with at-risk families in new ways.

May 15, 2020

Pandemic Deaths Are Almost Impossible to Count. He Invented a Way to Estimate Them.

Wade Hampton Frost’s calculation method is still used by the CDC today.

May 13, 2020

An Inside Look at the Job of a Contact Tracer

Contact tracing is key to controlling COVID-19. Public health detectives are on the case.

May 12, 2020

An Unequal Response: COVID-19 and Disability

The COVID-19 crisis has exacerbated longstanding inequities in access to health care for people with disabilities.

May 8, 2020

40 Years in a Post-Smallpox World

The eradication of a lethal viral disease delivers hope—and tools—in the fight against COVID-19.

May 7, 2020

Five Variables that Can Affect COVID-19 Symptoms, Prognosis, and Outcomes

What explains the range of COVID-19 infection outcomes?

May 5, 2020

Temporary Gun Storage: A Safe Option When Families Must Stay Home

A new online map guides firearm owners to locations for voluntary, temporary gun storage.

May 4, 2020

Why COVID-19 Hits Men Harder

Scientists aren’t sure why, but biology and behavior offer possible clues.

April 29, 2020

Measuring Mental Distress Amid a Pandemic

Measuring Mental Distress Amid a Pandemic and Understanding COVID-19’s Psychological Effects Over Time?

April 28, 2020

10 Tips for Making Sense of COVID-19 Models for Decision-Making

The COVID-19 pandemic is a complex phenomenon but models can be useful. Here are tips for making sense of COVID-19 models for decision-making.

April 24, 2020

Spotting Rumors and Misinformation About COVID-19

Simple steps you can take to verify the authenticity of content related to the novel coronavirus.

April 24, 2020

Recommendations for a Metropolitan COVID-19 Response—Special Area of Emphasis: Guidance on Protecting Individuals Residing in Long-Term Care Facilities

Recommendations for how local municipalities can help support COVID-19 pandemic preparedness and response efforts within long-term care facilities, like skilled nursing facilities, nursing homes, and assisted living facilities.

April 23, 2020

The Potential—and Limits—of Antibody Testing

While antibody tests can reveal past exposure to the novel coronavirus, they don’t yet provide proof of immunity.

April 21, 2020

How to Lead With Emotional Intelligence in the Time of COVID-19

Leadership will be one of the most heavily tested skills throughout the coronavirus pandemic.

April 21, 2020

The Other Time a U.S. President Withheld WHO Funds

Dean D.A. Henderson led a Reagan-era campaign to restore U.S. support for the WHO.

April 20, 2020

Contact-Tracing Technology: A Key to Reopening

Digital tools that bolster human efforts are critical to preventing future COVID-19 outbreaks.

April 17, 2020

A Plan for a Phased Reopening Guided by Public Health Principles

The Center for Health Security’s report targeted for governors and detailing a potential path for reopening nonessential businesses, schools and childcare facilities, outdoor spaces, public transportation, mass gatherings, and interpersonal gatherings.

April 17, 2020

Partners in Fighting Coronavirus Among Native Americans

Glaring health disparities and socioeconomic factors complicate the COVID-19 response in Native American communities.

April 16, 2020

How Health Disparities Are Shaping the Impact of COVID-19

Leadership and access to health care resources and information are key to supporting the hardest-hit communities.

April 13, 2020

Recommendations for a Metropolitan COVID-19 Response— Special Emphasis Series: Guidance on Protecting Incarcerated Individuals

Ensuring the safety of incarcerated persons and the other individuals who interact with them in these settings is critical to preventing transmission of COVID-19 not only inside the facilities, but also in the wider state community.

April 9, 2020

Gun Sales Surge Amid Coronavirus Anxiety

Experts fear a wave of suicides and domestic homicides may follow.

April 8, 2020

Protecting Your Mental Health During the Coronavirus Pandemic

The outbreak can have profound consequences for psychological health.

April 3, 2020

How to Prevent Social Isolation from Making Loneliness Worse

Form social connections during social separation—advice from former Surgeon General Vivek Murthy

April 3, 2020

5 Ways the U.S. Botched the Response to COVID-19

The best way to ensure a better response to the next crisis is to understand how we failed on this one.

April 3, 2020

Detained and Vulnerable to COVID-19

A coronavirus crisis looms at immigration detention facilities in the U.S.

April 2, 2020

Recommendations for a Metropolitan COVID-19 Response

Seven steps cities should take immediately to slow and prevent the transmission of the novel coronavirus.

April 2, 2020

COVID-19 Tradeoffs: Feeding Others and Staying Fed

Securing our food system means protecting food workers and buyers.

March 31, 2020

Dangerous Curve: Predicting the Coronavirus Peak

What will the peak look like for COVID-19 in the U.S? And when will it occur?

March 31, 2020

Too Many COVID-19 Patients, Too Few Ventilators: An Ethical Framework to Guide Hospitals

As COVID-19 caseload escalates, hospitals may face agonizing decisions on ventilator access.

March 30, 2020

Food Security in the Time of COVID: It’s Not Charity, It’s Justice | Johns Hopkins Center for a Livable Future |

The pandemic is new to us, but the virus is drawing our attention to long-existing problems in our food systems, and exacerbating them.

March 30, 2020

The Right Mask for the Task

How much protection do different masks offer, and what are their limits?

March 26, 2020

COVID-19: Infection Control in Your Home

If someone in your home is sick—whether confirmed or suspected to be COVID-19—there are ways to reduce the risk of transmission.

March 26, 2020

A Doctor's Perspective from Wuhan

Bin Cao has worked on the front lines of patient care in Wuhan for the past few months.

March 25, 2020

A Drug for COVID-19 May Already Exist

Some drugs approved for other illnesses may be effective treatments for COVID-19.

March 20, 2020

COVID-19 Myths vs. Realities

We separate COVID-19 true from false, based on the best science and expertise available.

March 20, 2020

Coronavirus and Underlying Conditions

Having an underlying condition is one of the biggest risk factors for developing serious illness when infected with COVID-19. What is an underlying condition and what should you do if you have one?

March 17, 2020

Johns Hopkins Public Health Expert Fields Coronavirus Questions in Reddit AMA | The Hub

Josh Sharfstein, former Baltimore City health commissioner, discusses social distancing, hand-washing, and the importance of helping those who are at high risk

March 3, 2020

Could a Serum Prevent Coronavirus? A Johns Hopkins Immunologist Explores the Idea | The Hub 

Infectious disease expert Arturo Casadevall looks to a forgotten case study for ways to prevent the spread of coronavirus

February 28, 2020

What the Coronavirus in China Shows Us About Food System Resilience | Johns Hopkins Center for a Livable Future

Pandemics are not just a public health issue, but a food systems issue – what makes a food system resilient?