COVID-19 Answers From Infectious Disease Expert Tim Lahey, MD

Tim Lahey, MD, infectious disease expert at the University of Vermont Medical Center in Burlington

Posted April 6, 2020 by UVM Medical Center

As we seek to protect ourselves and our loved ones while preventing the spread of the highly contagious respiratory illness known as COVID-19, accurate information and expert guidance is more important than ever. Here, Tim Lahey, MD, an infectious diseases doctor and professor of medicine at the University of Vermont's Larner School of Medicine and the University of Vermont Medical Center, offers his take on some of our most pressing questions, as well as some personal perspective.

If I was infected with the virus, will I be immune after I recover? Can I transmit the disease after I recover?

We don't know the answer yet. After infection with most viruses, immunity occurs. Antibodies were detectable for 2-3 years after people were infected with SARS, the closest cousin to the virus that causes COVID-19. If it's present, immunity can slow the spread of a viral infection through the population, because eventually everybody around the infected person is already protected. So far we have not seen any convincing cases of relapsed COVID-19, which makes me hopeful immunity does occur.

How long will it take until we have a vaccine?

A vaccine against COVID-19 is currently in clinical trials. Even with the pace accelerated, it'll still take several months to a year to determine if it works. A vaccine, therefore, might help protect people from a wave of infections that occur after physical distancing measures are relaxed, but it won't help us with the first waves of the epidemic.

People are buying up cases of bottled water. Can coronavirus infect the water supply?

There is no evidence that COVID-19 is primarily transmitted via the water supply or food. Certainly, COVID-19 contaminates surfaces, which can include food in the grocery store, so I do wash my vegetables once I get home like I always do. In the meantime, I'm drinking tap water guilt free.

Will wearing a homemade face mask when I leave my home protect me or those around me from infection?

We don't know for sure. Some studies with influenza viruses suggested that cloth masks can increase the risk of infection by holding onto the body's moisture and thus trapping viral particles near the face. Other studies showed that a fraction of viruses blown against a cloth mask in a lab setting were stopped, suggesting maybe the mask could help prevent transmission. And that's it. That's what we have – definitely not the best evidence on which to base an important decision. And yet, here we are, with the world clamoring for a decision. Knowing how anxious people are to protect themselves and others from COVID-19, and how that anxiety might tempt the general public to use up some of the medical masks that are desperately needed to keep doctors and nurses safe, the CDC and the State of Vermont have recommended the general public wear homemade cloth masks. The WHO has not. As time passes, we'll see how this evolves. In the meantime, the UVM Health Network is directing all employees to wear medical masks for in-person patient care activities and cloth masks for staff who are not in close patient contact, as well as members of the public who enter its facilities. Staying at least 6 feet away from people outside your home and good hand hygiene are still the best ways to prevent infection.

Should I wear gloves in public?

I wear gloves while caring for patients, but never out in public. The reason is that gloves can be contaminated in exactly the same way as your hands, so they're really no better at protecting you from whatever you pick up in the outside world if you touch your face. It's not like the virus burrows in through your skin or anything like that. Stick with handwashing.

Is it safe to eat takeout food?

It's safest to cook your own food at home because you control the cleanliness of food production, and you aren't coming into contact with other people out in the world. But, if you can't cook for yourself, or just can't handle another peanut butter and jelly, take reasonable precautions. Wipe down containers and wash hands after pickup or delivery. Stay at least 6 feet away from other people during pickup and try to stay outside or in well-ventilated spaces. And please, pretty please, don't get tempted to stay at or near the restaurant to eat with friends. Social distancing is the most important way we can all save a life, right now.

What kind of precautions do I need to take when I return home from an essential shopping trip?

After returning from errands, I wash my hands, I wash vegetables and fruit from the market. Some health care workers, who are highly exposed to the virus on the job, are changing their clothes and shoes outside the home in order to avoid spreading COVID-19 to their families. We don't know if they need to, although it seems like a reasonable precaution. Similarly, it's unknown whether the general public, which is far less exposed, needs to take those measures.

Does it help to rim my nostrils with sanitizer before I go out? Or spraying with disinfectant when I get back?

Wow, that's a creative idea. I have no idea! And, I admit, I'm skeptical: viral particles floating in the air after someone sneezes are most likely to float into the nose and not necessarily stop at the nostrils to ask permission.

Here's my approach to things like this: we all want to have control over this frightening epidemic. It makes our minds go through all the possible options. This is a great thing: it can fuel human ingenuity. Yet, it's good also to stick to what's proven, particularly when it's pretty easy to do. Right now, I think it's reasonable enough to adhere to physical distancing measures, to wash your hands, and to stay away from folks who are sick.

What kind of safety precautions do I need to take with my pet? Can we give coronavirus to each other?

The virus that causes COVID-19 (SARS-CoV-2), came from bats, perhaps by way of a pangolin (a scaly anteater). Epidemiologists are still sleuthing in Hubei, China, to learn more. There is no sign that domestic animals can transmit COVID-19, though. Dogs and cats, etc., have surfaces that can be contaminated like any other, and so theoretically they could move the virus from a sick person to someone who is well. As a result, the CDC suggests that people who are sick (with COVID-19 or something else) have healthy people care for pets and to keep the animal away from the sick person so transmission is less likely.

We have to be realistic about things like this, though. Dogs and cats may not understand this logic, and we may need some pet affection in a trying time. This gets to an important point: we should take reasonable measures to lower transmission risk, but at a certain point we have to accept the risk will never be zero. We have to find a way to live our lives in the middle of an epidemic.

Is there medication to treat the virus?

Not yet. Multiple experimental drugs are being tested in clinical trials. That means that so far those drugs could help, hurt or do nothing. Whenever someone says there's a drug being tested against a scary threat like COVID-19, it's easy for us to assume it must do something. It worked in a test tube, right? But the field of drug development is rife with examples of drugs that seemed promising in early tests and either did nothing or ultimately were more harmful than helpful. That means some patients will likely receive experimental treatments if they are sick enough for their doctors to be willing to try anything, but most people will not. Though there is no proven treatment, patients experiencing more severe symptoms can get supportive care (ex. oxygen, IV fluids, etc.), if needed.

I hear one experimental medication, hydroxychloroquine, has proven uses for other patients. Will those other patients be endangered if we use hydroxychloroquine for COVID-19?

This is an incredibly important question. Some of our patients have autoimmune conditions for which the use of hydroxychloroquine is proven to work. If mass enthusiasm for the experimental use of hydroxychloroquine for COVID-19 leads to supply shortages, that experimental use could well endanger people with proven need for the drug. We are closely monitoring the supply of hydroxychloroquine and have taken steps to protect proven use of hydroxychloroquine at the same time experimental use is possible.

Should I try to suppress the fever of COVID-19, or is that dangerous?

Both acetaminophen (Tylenol) and non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen can reduce fever and relieve other symptoms of COVID-19 such as muscle aches. There's no benefit to lowering a normal fever, and a fever is part of your body's natural response to an infection. As a result, I tend not to treat fever or other symptoms unless they're really making me uncomfortable.

Early in the COVID-19 epidemic, some researchers put forward a hypothesis that NSAIDs, like Advil or ibuprofen, might worsen COVID-19, and so initially the World Health Organization (WHO) warned people against that class of drugs. There really is no data that NSAIDs are any better or worse than acetaminophen. That was just conjecture that the WHO has since retracted. I'd say if it works, take it at the manufacturer's recommended doses if it helps you feel better.

Can home remedies treat or cure coronavirus?

There is no known drug prevention or cure for COVID-19. Anybody who tells you they have one is either engaging in wishful thinking, or trying to sell you a bill of goods.

Tim Lahey, MD, is an infectious diseases doctor and professor of medicine at the University of Vermont

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