I recently had the opportunity to hear a case presentation of a pregnant woman in the second trimester who developed fever, body aches, and lethargy. Her symptoms progressed quickly and were so severe that she was unable to eat or drink. Her obstetrician admitted her to the hospital for monitoring and treatment of the symptoms. While the physician team was trying to figure out what was wrong with her, one of the diagnoses they considered was parvovirus (parvo). The group of us listening to the presentation paused and thought, “Isn’t that what dogs or cats get?” Pets can get a form of parvo that can affect their intestinal or cardiac systems, but there is also a human parvo.
Pet Parvo
First and foremost, the canine or feline version of parvovirus is not the same as the human kind. Humans cannot contract parvo from their pets (or other people’s pets) nor can a pet contract parvo from a human.
While parvo is a serious threat to pets, it is preventable with vaccinations from a veterinarian. (I admit, being the proud owner of two incredible beagles, I checked to be sure both were vaccinated against canine parvo as soon as this case presentation was over!)

Human Parvo
Human parvovirus, also called the “B19 Virus” or the “erythrovirus B19”, is the first human virus identified in the family parvoviridae, genus erythroparvovirus. What does that mean? It’s contagious! Especially from contact with saliva or nasal secretions from an infected person. And who is the most infected? Kids, of course!

Children tend to develop a condition known as “Fifth Disease” which is a combination of bodily symptoms like fever, lethargy and a distinct body rash. Most adults have contracted parvovirus at some point in their lives and built up immunity to it. The good news: most of adults are, therefore, immune. However, there are some who do not have immunity and parvovirus can make life miserable for a few days or weeks while the virus runs its course. Add pregnancy to the mix, and it’s a different scenario.
Why It Matters For Pregnancy
The problem with human parvovirus is that it inhibits the production of red blood cells. Red blood cells live for several days, so they typically outlive the lifespan of the virus. In a perfect scenario, the virus dies off and red blood cells begin reproducing just as others in the body start to die off. In pregnancy, the virus can cross the placenta and get into the baby. Once in the baby, there is a chance (about 1-3%) of miscarriage (or stillbirth), fetal anemia, inflammation of the baby’s heart, or if severe, a condition known as hydrops where, essentially, excessive fluid accumulates in the baby’s tissues.
Timing is key: if a woman contracts parvovirus early in the pregnancy, she is more likely to have symptoms or have issues develop with the baby. Conversely, women who contract parvovirus from mid-pregnancy to the time of delivery have less chance of it impacting the baby.

Either way, a pregnant woman with parvovirus is sick. The usual symptoms of lethargy, fever, body aches and loss of appetite seem to be magnified. As practitioners, we prefer to evaluate women with any of these symptoms promptly, so we can initiate treatments to alleviate the symptoms. We try to prevent women from developing fevers and do our best to keep women eating well and drinking sufficient amounts of liquids. We also want to watch the baby with sonograms. If a mom is sick enough, we might admit her to the hospital, so we can give her intravenous hydration and monitor the baby on a more consistent basis.
What To Do
What can you do to minimize the chance of being exposed to parvovirus? From the start, pregnancy is a great time to get into the habit of good hand hygiene– making it second-nature. Hand sanitizers are helpful, but nothing takes the place of washing your hands with warm water and soap. Pregnancy is the time to become almost compulsive about hand-washing and making it a hard-wired habit. Avoiding people who are sick, especially kids who are ill with visible nasal or upper respiratory symptoms, helps minimize exposure. Similarly, staying away from adults who are sick and avoiding kissing, hugging, or sharing utensils or drinking glasses greatly reduces the likelihood of exposure.
Key Takeaway?
Parvovirus B19 is real and can pose a threat to certain pregnant women. However, the illness is preventable with attention to good hand-washing and staying away from people who are visibly sick. If any symptoms develop, regardless of the cause, contact your health care provider and discuss them to see if further evaluation is warranted. Fever, body aches, nausea, vomiting or diarrhea are symptoms to report whenever they occur, either alone or in combination.
For more information, check out the Centers for Disease Control and Prevention (CDC) webpage on parvovirus B19, or share any questions or comments here.