The latest on COVID-19, the Delta Variant, and Vaccines - School of Health and Human Sciences

Dr. Jennifer Toller Erausqin — Dr. Jennifer Erausquin

The global outbreak of the novel coronavirus is quickly approaching the two-year mark, and although infection and hospitalization rates are trending down, the fight against the pandemic is far from over. At publication, the United States had a daily average of over 100,000 reported cases and 72,000 hospitalizations, according to The New York Times.

There are still questions about COVID-19, vaccines, and the new Delta variant. At times, it can feel like information overload. We checked in with UNCG School of Health and Human Sciences’ resident pandemic expert, Dr. Jennifer Toller Erausquin, to help extract fact from fiction. Erausquin is an associate professor in the Department of Public Education and a social epidemiologist who studies the way social determinants ― such as social structures, institutions, and relationships ― affect patterns of disease among populations.

In the beginning of the pandemic, there was a lot that we didn’t know. Instead of wearing masks, we thought precautions like wiping down our groceries and washing our clothes after being outside would help contain the spread. Is it funny to look back on that, knowing all that we know now?

In epidemiology, when there’s a new or novel illness or outbreak of a known illness, there are a couple of steps experts will start with. What are the symptoms a patient typically experiences? What signs do healthcare providers see among their patients? What combination of signs and symptoms is going to count as a case? Once we have a case definition, we start counting and then dig into, how is this transmitted?

Early on in the pandemic, we were coming from a starting point of what we know about other respiratory illnesses. We didn’t know if the virus that causes COVID-19 illness is spread through droplets or is aerosolized. We didn’t know if it could stay on multiple surfaces, or for how long. It’s understandable that information was evolving.

We learned over time that this virus is probably less transmitted on surfaces, including our clothes and groceries, and probably most transmissible in the air, and that droplets may stay in the air longer than we thought.

There’s been little change in the non-pharmaceutical interventions (NPIs) we came up with at that time. We know now that we don’t have to wipe down groceries, but hand washing and avoiding touching the face is still a good idea, as is maintaining physical distance and good ventilation.

Initially, there was confusion about recommendations about face coverings. Now we have an understanding that for this particular virus, wearing face coverings is an important, effective strategy. An additional tool we have now that we didn’t have a year ago is safe and effective vaccines approved for us in the U.S. They are free and available in lots of locations.

Anyone who had been waiting for additional scientific information, or to see what happens among friends and family members who are vaccinated ― well, we now have tens of millions of people vaccinated. It’s very clear that vaccines are safe and a key tool for combating this epidemic.

Delta is currently the predominant variant of the coronavirus in the United States. Recently, data emerged that it was more infectious and was leading to increased transmissibility when compared with other variants, even in some vaccinated individuals. What can you tell us about Delta?

The Delta variant is more contagious than previous variants. It’s not the only one that exists in the world, but in the U.S., it’s the major cause of COVID-19 illness right now. We know this because we do genetic analysis on a sample of people who test positive for COVID-19.

This information allows scientists to understand which variants exist here and to estimate the proportion of COVID-19 cases due to the different variants. The Delta variant is probably at least two times more infectious and transmissible than the original coronavirus variant.

You may have seen a statistic called R₀ (pronounced “R naught”), which is a measure of the average “spreadability” of an infectious disease ― for example, how many people I’m likely to infect if I get sick. The original coronavirus has a R₀ between 2 and 3, on par with the 1918 flu pandemic. Delta has an R₀ between 5 and 7. That is why it is so important to be vigilant about stopping infections.

What do the symptoms of the Delta variant look like? Are they the same as the coronavirus?

There does seem to be a difference in symptoms. Cough and loss of taste and smell are less common with the Delta variant, but other symptoms like headache, sore throat, and fatigue are the same.

There is some evidence that the Delta variant causes more severe illness compared with the original variant. Hospitalizations and deaths are largely among those who are unvaccinated.

If you’re young and healthy, will you have a less severe case?

If someone is young and healthy, they may be convinced that they are not personally going to have a severe case if infected, but we’ve seen exceptions in young and healthy people getting seriously ill.

At a population level, younger and healthy people do seem to be at lower risk of severe disease. But that’s why vaccines among this group remain important from a public health perspective.

We need vaccines not just to protect ourselves, but also to protect other people: for example, to protect kids under 12 who can’t yet get vaccinated; to protect people with compromised immune systems that don’t have a strong enough response to the vaccine and therefore have incomplete protection.

This is a case of needing to better understand how our individual decisions about getting vaccinated have real, life-or-death implications for communities at large.

Are children at greater risk for the Delta variant?

This goes back to the Delta variant being more easily transmissible. This means more children are getting infected compared with earlier in the pandemic. While many adults in the U.S. have gotten vaccinated, children under 12 can’t get the vaccine yet, so our population at risk has shifted somewhat.

It does look like even in children, the Delta variant is more likely to cause severe illness compared to the original variant and other prior variants.

Do we still need to “flatten the curve”? How do we determine what’s safe to do versus what puts ourselves and others at more risk?

When you and I talked at the beginning of the pandemic, our goal was to flatten the curve – to do all we could to reduce new infections so that our healthcare systems would not be submerged by COVID-19 patients and the care they required.

We need to return, at least in some senses, to that goal. Part of what we are seeing is our hospitals and healthcare systems are overwhelmed with caring for patients with coronavirus. In many places, people who need hospital beds ― whether it’s for COVID-19 or other conditions ― are having a hard time getting the care they need. This is true for adults and children. Though hospitalization from COVID is less common in children, most places in the U.S. also have fewer hospital beds and specialty care for children.

It’s really hard for me to comment on “what’s safe” because it’s so dependent on the level of risk that different people are comfortable with. What I’m comfortable with for my family and myself may not seem safe for my neighbor or coworker, or my kids’ friends at school. We have different circumstances. Everyone is going to make their own risk-benefit judgment.

When you and I spoke back in March 2020, experts and the public at large were hoping this would be a relatively short-lived circumstance – that we would flatten the curve and the virus would peter out similar to 2009 with H1N1 (swine flu), and we would all move on. Then it became clear we were in this for a longer haul. Now more than 18 months in, we understand we might be in this even longer.

Some behaviors and changes we implemented early on are not ones we can maintain in the longer term. Some people could never work from home. Others can’t work long-term at home or have children learning from home for the indefinite future. The uncertainty of how long this is going to last weighs into risk calculation ― what am I okay with, if this is what our world is going to be like for a while?

From a public health standpoint, how can we end it?

Virologists, epidemiologists, and infectious disease experts have made it clear that vaccinations will be an essential part of how we get through and beyond this. Without masks and vaccinations, it’s going to be so much longer, more deadly, and put us at increased risk of other more serious variants continuing to develop.

There is an urgent need for vaccination. The vaccines we have available are not perfect, but they are incredibly effective at reducing the number of total infections, symptomatic infections, hospitalizations, and deaths.

It is true that vaccinated people can become infected with COVID, and they could still transmit the virus to others; however, the period over which they are infectious to others is much shorter and they are much less likely to get a serious case or transmit to others.

Vaccine decision-making in general involves people asking themselves, how much personally am I at risk, and am I going to get sick from whatever the virus is, and then is it worth it to me? Whether that’s a pain in the arm or whatever side effects or the cost of transportation and logistics.

I’ve seen some reports about the rollout of the polio vaccine. That one is interesting in part because that was rolled out as a vaccine for children. Eleven years of research went into development of that vaccine, and then when it was available, kids and parents were lining up. Everyone wanted to get it.

At that time, many people knew someone who had polio as a child. Polio effects were usually directly observable: gait differences, people wearing leg braces, or using a wheelchair. It was a visual reminder that polio can be a very serious illness with long-term impact. That was a motivator for parents having their kids vaccinated.

With COVID, I’m not sure it’s entirely visible to the population how serious it can be. When a disease like this early on in a pandemic affects largely older adults, it can be easy to justify: Okay, they were weak and frail and had other health issues.

Less attention is paid to healthy people and young people who have become seriously ill and died, as well as long COVID and the serious and debilitating long-term effects some are having even after a mild case.

It may be a perfect storm of cultural and political events, ways of receiving information, and also a lack of public awareness about the potential for serious illness that together contribute to hesitancy to take the vaccine.

What else can we do?

To understand what we can do, I like the metaphor of cheesecloth. The tools we have available to us, NPIs and vaccines, need to be layered together to combat the virus. If you pour liquid over one layer of cheesecloth, it will go right through.

If you have multiple layers, you’re covering up some of the holes, more with each layer, and less liquid will flow through it. Similarly, the more layers of different protections we put on– such as vaccination, face coverings, and social distancing – the less likely the risk of infection.

I think the University has done a pretty good job of giving faculty and staff and students access to many of these tools, including the requirement for vaccination or periodic testing. It’s all part of a strategy to use multiple tools to reduce risk as much as possible while balancing peoples’ need to work, engage in research, and go to class.

Read previous interviews with Dr. Erausquin:
Public Health Expert: COVID-19 and social distancing, March 13, 2020
Public Health Expert: The Latest on COVID-19, August 6, 2020

Story by Elizabeth L. Harrison, School of Health & Human Sciences
Photography by Martin W. Kane, University Communications