Episode Transcript
Dr. Kirtly Jones: In Utah, one child every day is born with congenital CMV infection. Well, what is CMV, cytomegalovirus? What is it about this virus that doesn't make people sick, grown-ups sick, but can make a fetus sick? This is Dr. Kirtly Jones from the department of obstetrics and gynecology here at University of Utah healthcare, and today on The Scope, we're going to be talking about CMV.
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Dr. Kirtly Jones: Today in the studio with us here at the University of Utah healthcare, we're talking with Dr. Erin Clark. She's a specialist in maternal fetal medicine and has been a part of our focus to educate women and maybe do some research to help women and their babies who might be exposed to CMV. Welcome, Dr. Clark. Welcome to the studio.
Dr. Erin Clark: Thanks for having me.
Dr. Kirtly Jones: So first of all, let's talk about what a maternal fetal medicine specialist is.
Dr. Erin Clark: So a maternal fetal medicine specialist is someone who takes care of high risk pregnancies. High risk pregnancies can be high risk for a number of reasons. One reason is that mom has a medical condition like high blood pressure or diabetes. One is because the fetus has a complication, something like spina bifida. Or the pregnancy itself has a complication like preclampsia. So a maternal fetal medicine specialist takes care of all of those conditions. Any condition that a mom has outside of pregnancy that makes her special is something that a maternal fetal medicine specialist would take care of.
Dr. Kirtly Jones: Okay, that's helpful. And the issue that we're talking about today is exposures to viruses during pregnancy. We know that we worry about some viruses more than others, but specifically cytomegalovirus or CMV. So tell us a little bit about CMV. Is it like a flu virus or is it like an HIV virus? Tell us why it's important for us to know about it.
Dr. Erin Clark: So cytomegalovirus is a really common virus in the environment. Most of us have seen cytomegalovirus by the time we're middle age. It for most people presents like a common cold or like a flu. For those adults who have an intact immune system, it really is a very mild illness. Fetuses are the exception though. Fetuses are particularly susceptible to the virus and so when mom gets it, particularly for the first time, during pregnancy and passes that virus to the fetus, it can affect the fetus in a variety of ways. That virus can attack the fetus' brain, eyes, ears, and cause long-term problems like developmental delay, blindness and deafness. So while CMV in a healthy adult population is not a big deal, we really strive to prevent transmission to pregnant women so they can therefore prevent transmission to fetuses.
Dr. Kirtly Jones: Well, you know, over the years, specifically the measles virus was pretty bad for moms and their fetuses so we developed a vaccine for the measles virus partly because when kids get the measles they can get sick but more because it was so bad for moms. How are we doing on a CMV vaccine?
Dr. Erin Clark: Unfortunately not very well. So there is no effective vaccine against cytomegalovirus which is one reason why it remains a really important public health problem. We don't have currently an effective treatment or preventative strategy for when women get that virus for the first time in pregnancy.
Dr. Kirtly Jones: Okay, well then, so we know that some viruses get through the air and some viruses you get by kissing your sister and some viruses come only by blood-borne fluids so tell us about how you get CMV.
Dr. Erin Clark: So CMV is carried in all body fluids so it's present in tears, it's present in mucous, it's present in saliva and in urine, and contact with any of those fluids can mean that you contract the virus from someone who's infected. It may seem like we don't have contact with those things very often, but in fact we really do. When you think about caring for a young child, it means that you're in contact with those things more than you think you are. For instance when mothers are feeding babies, oftentimes that spoon goes in your mouth and then their mouth. You share food a lot with toddlers for instance.
Dr. Kirtly Jones: Oh yeah, you put it in your mouth so they can see that it's safe and yummy and now some for you.
Dr. Erin Clark: Yeah, mom has a bite, baby has a bite. It becomes more common. And things like wiping noses, giving little kids kisses that tend to be a little bit more slobbery than it would be between two adults. If you think about those instances, it's actually a pretty common exposure. So when we talk about, okay, how do we prevent moms from getting the infection for the first time, we concentrate on some of those mechanisms and say, well, avoiding contact entirely is impossible, reduced exposure does seem to be effective in preventing transmission of the virus. So things like hand washing after you change a child's diaper or after you wipe a runny nose, making sure that you avoid sharing utensils if at all possible, keeping a binky in the baby's mouth and not putting it in your mouth to clean it off or anything like that. Those types of measures have actually been shown to have some impact at reducing the virus.
Dr. Kirtly Jones: Let the dog lick it off, right? We've talked about that, yeah.
Dr. Erin Clark: Something like that.
Dr. Kirtly Jones: So the other question is if, you said that it's worse if a fetus is exposed if a mom gets it the first time, how do you know if you've been exposed before? Should we screen all women?
Dr. Erin Clark: Half of all women who are pregnant have already been exposed, and they're certainly at lower risk of contracting a serious infection because just like some other types of infections like measles if you've had it before, you're less likely to have it again. But some proportion of women can still get it so they're at less risk but not no risk. Those women who haven't seen it are at the highest risk, but we recommend because nobody is totally immune from this virus, those things that we talked about as far as avoiding exposure to body fluids is recommended for everybody.
There's been a lot of talk about whether we should screen all pregnant women, but that effort has been inhibited by a couple of things. One, the fact that we haven't really been able to tell historically by lab tests with any reliability whether it's a first time infection or not. And we don't have an effective strategy to ameliorate the disease, to either prevent it from transmitting to the fetus or reducing the consequences so that discussion about a big public health effort to screen has really sort of died on the vine until we have an effective preventative strategy.
Dr. Kirtly Jones: I know the university is trying to do some new research. Given that we don't have an antibiotic for viruses and we don't have a vaccine that can lower the risk, is there anything that we think might be helpful and what kind of research are we doing about this?
Dr. Erin Clark: There's certainly a handful of reasons why a woman should be screened other than just sort of general population screening, and one is if they present during pregnancy to their doc and they've got a flu-like illness, CMV should be considered and screening should be considered because those women are at higher risk for having a primary infection. If a pregnant woman has a known contact with a child or an adult who has a known CMV infection, that might be a reason to also screen. If an ultrasound in the middle part of pregnancy is suspicious for findings that could be CMV related, that's another reason to start down that pathway. So there are some reasons even though we're not doing population-based screening to think about screening. We've been educating docs in the state of Utah about some of those reasons and when to screen.
Outside of that, it really comes to clinical trials. We are looking for a way to know if a woman has had an early infection in pregnancy and a way to prevent transmission to the fetus or at least some of the sequelae of that infection. So there's a national randomized control trial that's going on right now that's sponsored through the National Institute of Child Health and Human Development, 14 sites across the nation are screening women early in pregnancy with a very specific lab test that looks for antibodies to CMV and says are there signs of an early, recent infection. And then offers those women randomization to either standard of care which right now is nothing or a drug that's essentially antibodies to CMV to see whether we can prevent transmission or some of the effects of the virus. So that's going on right now in Utah at three sites, University of Utah, Intermountain Healthcare, and McKay-Dee Hospital. So at those three sites, University of Utah, Intermountain Medical Center, McKay-Dee, we're actively looking for women early in pregnancy to do that screening test with the hope that we pick up some who have an early infection and who can enroll in the trial.
Dr. Kirtly Jones: So with a lot of things about virus, we still have a lot to learn. I think a lot of people are trying to do the right thing and some people are probably working on a vaccine and some people are working on treatment strategies, but in the meantime for women who are pregnant or are trying to get pregnant right now, just be careful a little bit about fluids, huh?
Dr. Erin Clark: Yeah, and I think my best trio of advice for folks who are early pregnant, thinking about pregnancy is to be careful about those exposures; just use good hand washing, we're supposed to do this after we change a diaper anyway, right, but especially with saliva and such just being more careful than maybe you have been in the past. To avoid known exposures if you know of a little kid who has CMV to maybe just make sure that you're using good hand washing. It doesn't mean you need to avoid that individual all together, but just avoid those exposures to body fluids. And the third is if you're in early pregnancy and getting care at the University of Utah, Intermountain Medical Center, or McKay-Dee consider participating in the trial to be screened and potentially randomized if you show evidence of an early infection. That's it. That's all we have.
Dr. Kirtly Jones: Pregnant ladies wash your hands. Talk to you later. This is Dr. Kirtly Jones and this is The Scope.
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