Las Vegas Sun

March 28, 2024

Q + A: BRIAN LABUS:

UNLV disease expert discusses monkeypox risks

Monkeypox

Cynthia S. Goldsmith, Russell Regner/CDC via AP

This 2003 electron microscope image made available by the Centers for Disease Control and Prevention shows mature, oval-shaped monkeypox virions, left, and spherical immature virions, right, obtained from a sample of human skin associated with the 2003 prairie dog outbreak.

Click to enlarge photo

Dr. Brian Labus

With over 50 reported cases in Clark County and a limited number of vaccine doses, monkeypox is emerging as a threat to public health.

In New York and California, officials have already declared public health emergencies because of the virus, which was first found in central and west Africa and has spread to dozens of countries and infected thousands of people. Most are men who have sex with men.

The Centers for Disease Control and Prevention reported 9,492 confirmed cases of monkeypox in the United States as of Tuesday. Sixty-four were reported in Nevada as of Wednesday, the CDC said.

Traces of the monkeypox virus have been found in the sewers around the Las Vegas Strip and at the wastewater treatment plant they flow into. The virus has not turned up at 14 other plants the team monitors in Southern Nevada.

There is no reason to panic, says Brian Labus, an infectious disease epidemiologist and assistant professor in UNLV’s School of Public Health.

That’s because the virus’s infection rate is much lower than that of COVID-19, meaning there is more time for local and federal efforts to mitigate the spread of the virus, he said.

The Sun sat down with Labus to talk about monkeypox, its risk to the public, and available vaccines. Here is some of what was discussed:

What is monkeypox? How contagious is it, and how dangerous is it?

Monkeypox is a viral infection that causes a fever and a rash, similar to the one you got as a kid with chickenpox. It spreads from person-to-person, but not that easily — it doesn’t spread as easily as COVID. You basically need direct, skin-to-skin contact (with somebody who has monkeypox), so it’s not something that you’re going to get just passing somebody in the grocery store or sitting next to them on the bus.

What activities are considered low-risk situations versus high-risk ones?

So, high-risk is basically direct physical contact with someone else. We’re not just talking about a handshake, we’re talking about basically skin rubbing against skin like we see frequently during sexual contact.

It’s also been said that monkeypox can be transferred through respiratory drops. How can it be spread in that way?

The lesions that you get on your body (can also) get inside your respiratory tract. If you are in close, face-to-face contact with somebody for an extended period of time — again, we’re not talking about being by somebody in a restaurant or on a bus, it’s usually intimate contact.

How many brands of the monkeypox vaccine are there and what is the protocol — is it a single shot, a series? How long is it effective for?

Well, there’s two different vaccines out there right now: one is approved for use against monkeypox and smallpox (JYNNEOS), and then we can always use the smallpox vaccine against monkeypox as well. It’s from the same family, they’re both considered orthopox viruses.

When we gave out the smallpox vaccine decades ago, it was a single shot and you were basically protected for life. We’re expecting a similar thing here. Based on what we know about other poxviruses, it’s probably not going to be something that you have to repeatedly get because (people) do mount a stronger immune response that’s very long lasting. It’s something that is going to protect you for a long period of time.

How effective is the monkeypox vaccine at preventing infection and mitigating symptoms?

From the past data that we have, I believe it’s about 85% effective in preventing monkeypox. So, we’re still learning about it because these things are new, but from the earlier trials, that’s what it seems like.

Once vaccinated, do people still have to take precautions to avoid getting and spreading monkeypox?

You’re not going to be reinfected with monkeypox; it’s something you’re going to get once and that’s it. It’s not something you’re going to get over and over again because of the way your immune system responds to it, which is very different from COVID.

If you get vaccinated before, it can prevent you from getting the disease. If you get vaccinated within a few days of exposure, typically less than four days after exposure, it can reduce the symptoms, but it cannot prevent the disease. But once you’re vaccinated, once you’ve had the disease, you’re immune and so you’re no longer part of that group of people who can be at risk and spread it to others.

What potential side effects does the vaccine have and how common are they?

The side effects of these vaccines – the most common ones – are what we see any time you get an injection, which is a sore arm, redness of the site. It’s just the kind of the response to having your skin broken by a piece of metal and having something injected into you.

But, what we’ve known about the smallpox vaccine is that there’s some small risk of cardiac effects. In this case, you’re talking about a disease that’s out there. If you’re in a high-risk population, the risk of getting monkeypox is going to be higher than the risk of any of these side effects, and that’s when you have to really compare.

Unlike the COVID-19 vaccines, the monkeypox vaccine was available quickly after the initial outbreak but in a limited supply. Why is that?

There’s a big difference between monkeypox and COVID. COVID, we discovered it when the first outbreak happened, and we had to create the vaccine from scratch. Monkeypox is something we’ve known about since probably around the 1950s – people get it regularly, it’s not a common thing, but it’s not one of these “once in a million years” things. Because of (previous outbreaks in the U.S. roughly 20 years ago and in Africa), we were able to start looking into developing a vaccine for that earlier. Plus, because we can use the smallpox vaccine as well, we can use a vaccine that has been around for a couple hundred years and use to now prevent this disease.

The reason it was in short supply is because there wasn’t a demand. We don’t produce a lot of it because we weren’t having any outbreaks of it. It wasn’t something that we needed to have millions and millions of doses because they would just go bad on the shelf.

How is the monkeypox vaccine made and how does that compare to the mRNA vaccines developed to target COVID?

In the big picture, they both work in the same way by giving your immune system a preview of the virus so you can fight it off quickly. That’s where the similarities end.

Right now, the vaccine is restricted to people who have been exposed to monkeypox. Do you expect a more widespread distribution?

It only makes sense to use it with people that are at high risk for monkeypox. It’s not something that we are going to use widely on our population, it’s not something that you’re going to see as a requirement to go into school, or a workplace, or anything like that.

It’s very different that we’re targeting the high-risk groups. With COVID, basically everybody is at risk, but with monkeypox, it’s really about which risk group you’re in based on your behavior. Most of the people we’ve seen be infected so far is through sexual contact in men who have sex with men – that’s not exclusively them, it’s just that (they’re) a higher-risk group. So if you’re somebody who’s having a lot of sexual partners, you’re going to be at much higher risk if you’re a man and they’re all men.

So, those are the people that would make sense to target next: basically, the people who haven’t been exposed yet, but have a high probability of being exposed.

So, is there going to be any risk of a community spread that may force us to start vaccinating other groups, like the immunocompromised or children?

If something changes with the virus and we start to see outbreaks in schools and things like that, then of course we’ll look at those things. But, right now, there’s no need for that because those groups are not at an increased risk. It’s sort of like putting out a fire. You go to the places that are on fire, you don’t just water down everything in the area because it doesn’t make sense.

What is the goal of vaccination when it comes to monkeypox? Is it to create a widespread herd immunity or is it more targeted than that?

I don’t think we need to look at (monkeypox) as an outbreak among the entire population. You look at the groups that are most highly affected by the problem and you try to control it in them.

In this case, it’s not something we’re seeing communitywide. It’s not like we have cases popping up all over the place and in Southern Nevada we’ve only had a few cases so far. When we look at those cases, we look at the common factors then we target those groups in our community – think of it as drawing a ring around where the affected people are and stopping transmission within that ring so it doesn’t escape. It’s really more of a strategy about containment as much as possible among the high-risk group, so we use vaccination, we use isolation, we use quarantine – the same things we used for COVID – that are actually much more effective against something like (monkeypox) because there are few cases and it’s a much more slowly-moving disease.

With monkeypox, do you believe we won’t have to worry about asymptomatic individuals, or do you think this is something we may see in the future?

With poxviruses, you typically don’t see asymptomatic individuals, and that’s what we’re seeing with monkeypox. With COVID, it was something that was brand new and we did not know the details of it. But with (monkeypox), we know more about poxviruses, we have a long history of controlling smallpox (and) chicken pox, so we understand those things and we have the advantage – time is on our side more than (with) COVID.

Is there a risk the monkeypox virus could mutate to circumvent the vaccine?

Well, that’s always possible. Any virus can mutate and change, but we’re using a whole virus (in the) vaccine. It’s not just one tiny, little piece, so we’re giving it a much bigger target to recognize and so little changes aren’t as big of a deal. So yes, I suppose that’s always possible, (but) it’s not likely.

There’s (also) less of a chance of mutation based just off time. The virus has to replicate in order for those mutations to spread and, at this point, it’s not spreading that fast, which helps us not see a bunch of mutations.

There was a lot of hesitancy among some groups of people about getting the COVID-19 vaccine, do you expect the same for the monkeypox vaccine?

There’s always going to be hesitancy. People are always going to be concerned about something they’re putting into their bodies, which makes perfect sense. What it comes down to is comparing the risk of the vaccine to the risk of the disease itself. If you’re not having sexual contact with somebody, if you’re not around a lot of people, if you’re not having that physical contact and it’s just you and a spouse or something like that, then the risk is basically going to be pretty much zero.

In that case, you have to decide if it makes sense to get a vaccine that is a very low risk, but it’s not a zero risk.

Are there therapeutic treatments available for monkeypox and how effective are they?

There aren’t a lot of treatments out there for the poxviruses (because) it’s not something we’ve dealt with much over the past 50 years, other than chickenpox. Luckily, when it comes to monkeypox, it’s not a deadly virus – deaths are pretty rare for monkeypox. It’s an annoying illness to have, it’s a painful illness to have, but it’s usually not a life-threatening illness to have.

There aren’t any FDA-approved treatments for monkeypox. Obviously there are things that are always being tested, and so those are things that we’re trying to basically study (to) see if they work, reduce duration of illness, (reduce) severity of symptoms or anything like that. There are the drugs out there that we’ve used for other things like smallpox that may have some effectiveness, but we don’t necessarily know. There’s a lot of things that we are trying out that are just general antivirals and stuff like that, but it’s still really hard to say because we’re still learning what medications work (versus) don’t work and what the pros and cons are.