An Illinois teacher who began feeling flu-like symptoms thought that was exactly what she had after tests for COVID and strep came back negative. But the symptoms that followed quickly changed her diagnosis.
Abby Parks, a 27-year-old special education teacher in Springfield, was about 18 weeks pregnant when she started feeling very sick with a fever.
The fever was followed by joint pain, but then came the rash.
Her school’s nurse, who had been seeing students with “really rosy, red cheeks,” suggested Parks might have the same infection.
“I got progressively sicker,” she said. “I was in bed with a fever for four or five full days.”
Then blood tests given by her OB-GYN came back positive for parvovirus B19.
Parks was referred to a maternal fetal medicine specialist, where a doctor discovered the virus had passed to the fetus in utero. The fetus had developed anemia, a very dangerous condition and doctors gave the fetus a blood transfusion in utero.
Parks was not alone in her diagnosis.
Cases of parvovirus B19 — more commonly known as Fifth disease or “slapped cheek syndrome” because of the red rash that covers an infected patient’s face — are rising in the U.S. On Tuesday, the Centers for Disease Control and Prevention issued an alert to doctors to watch for signs of the highly contagious seasonal virus.
Here’s what you should you know about the infection.
What is parvovirus or Fifth disease?
According to the CDC, the parvovirus B19 infection can cause anywhere from no symptoms to flu-like symptoms, rashes or joint pains, but for those with blood disorders or a weakened immune system, “infection can cause a low blood count.” Infection during pregnancy can also lead to complications, similar to Parks.
“Most people who get infected will not show any symptoms, and most people have already been infected by the time they’re 20 to 40 or so,” Dr. Scott Goldstein with Northwestern Children’s Practice said in a video posted to social media this week. “They say about half of people by 20 and 70% of people by 40 will have had this virus, whether they know it or not.”
Who is most at risk from parvovirus?
Most of the infections are among children ages 5 to 9, the CDC said. Since March, parvovirus has been circulating in Europe at unusually high rates, according to the European Centre for Disease Prevention and Control.
Most adults have already had the infection as kids and are still protected. However, the CDC warned that pregnant people and people with sickle cell disease who have never been exposed are at risk of serious illness.
Parks’ doctor, Kathy Bligard, an OB-GYN at Washington University Hospital in St. Louis, said: “Abby is not the only patient whose fetus has needed a blood transfusion in the last few months for parvovirus. It’s certainly something that I used to see maybe once every other year and have seen multiple times in the last few months.”
Bligard said parvovirus is dangerous to pregnant women because it can cross the placenta and infect the fetus and cause it to be anemic, which could lead to fetal death.
Parks has recovered from the virus, but her pregnancy is still at risk.
On Wednesday morning, after an ultrasound showed the fetus wasn’t receiving enough blood from the placenta, Parks was admitted to a hospital in Springfield to care for the baby.
“I do think it was lifesaving for the fetus,” Parks said about the earlier transfusion. “Because if that anemia had persisted, with that low blood count, the baby could have died,” Parks said in an interview Wednesday from her hospital bed.
Bligard said the virus makes it harder for a fetus to make new red blood cells. “In order to get oxygen to all of the important organs in our body, our body relies on having those red blood cells. And so it can cause heart failure or even progression to death by having low blood counts.”
Although the disease affects mostly children, when adults do catch it, it can cause more severe symptoms, including joint pain and anemia, which result from problems in creating red blood cells, said Dr. Vincent Iannelli, a pediatrician in the Dallas area. Low red blood cell counts can cause pregnancy complications.
Patients with sickle cell disease are also at high risk.
“Over the past month or two, I think we’ve been seeing more cases,” Iannelli said. Typically Iannelli would see one case of Fifth disease per month; he said he’s now seeing one to two cases per week, noting that the virus is more common in the spring and summer.
What are symptoms of parvovirus?
In children, Fifth disease is typically mild — its most distinctive symptoms include a fever and respiratory symptoms, followed by a red rash on the cheeks, then a “lacy” rash on the rest of the body, which may be itchy.
The rash appears toward the end of the infection and typically disappears in seven to 10 days, but it may last for several weeks. Importantly, someone with Fifth disease is no longer contagious once the rash appears.
“In kids who are infected, symptoms – if they do have them – usually start with the fever, muscle ache, sore throat and cough, so basically, flu-like symptoms,” Goldstein said. “This is usually followed by a characteristic rash that gives parvovirus its third name, called slapped cheek syndrome. By the time the rash comes out, kids are no longer contagious, but during the fever, sore throat, achy phase, it is a pretty contagious virus, as are most respiratory viruses.”
The rash can become more pronounced in heat and sunlight, but it doesn’t make the infection worse, Iannelli said.
The rash is most common in children, but adults who develop parvovirus may not experience it. Instead, the Mayo Clinic notes that the most common symptom for adults is joint pain, which can last anywhere from days to weeks.
Pregnant women who experience symptoms like joint pain and problems in producing red blood cells should notify their doctors immediately, especially if they know they have been in contact with patients infected with Fifth disease, doctors say.
How does it spread?
According to Goldstein, “parvovirus spreads like the common cold spreads.”
“It spreads from person to person, just like a cold, often through breathing, coughing and saliva, so it can spread through close contact between people and hand-to-hand contact,” the Mayo Clinic reported.
How concerning is it?
Iannelli doesn’t believe the rise in cases is cause for alarm.
“Fortunately, most pregnant women had it when they were kids, so they’re immune to it, but every once in a while we do see adults,” he said.
Ultimately, “if you’re healthy, it’s a mild disease,” Iannelli said. “If you have immune system problems or if you’re pregnant, early in your pregnancy you should tell your doctor. But for everybody else, it’s basically just a rash.”
He noted that the CDC alert was intended to raise awareness among doctors, not to concern the public.
Goldstein agreed.
“On a scale of one to five … in terms of the general worry for people who just have kids and are not pregnant, I would probably give it a one – one to just over one,” he said. “If you are pregnant, I might give it a two to three. It’s the kind of thing where if you’re pregnant and you don’t know if you’ve ever had parvovirus, and you can’t find out if you ever have, it might be worth being a little more conscious of being around groups of kids who could potentially be sick ruring this outbreak.”
How do you treat parvovirus?
According to the CDC, infections are typically mild and will go away on their own for otherwise healthy children and adults.
“Treatment usually involves relieving symptoms, such as fever, itching, and joint pain and swelling. For persons who develop a low blood count, treatment may include supportive care, blood products, and other specialized therapies,” the CDC notes.
Why is it called Fifth disease?
In the early 1900s, doctors developed a list of common childhood rashes to help them be more precise in their diagnoses. They identified six major rashes:
- Measles, a highly contagious virus that can cause rash, high fever and respiratory symptoms.
- Scarlet fever, a bacterial infection caused by group A streptococcus.
- Rubella, a viral infection also known as German measles. If someone is exposed during pregnancy, the virus can cause miscarriage or stillbirth. The CDC recommends two doses of the mumps-measles-rubella vaccine for children.
- Filatov-Dukes, no longer considered a distinct disease.
- Fifth Disease, or parvovirus B19, also known as erythema infectiosum.
- Roseola, a viral infection occasionally still called Sixth disease, which can cause high fever and rash.
There are now more recognized childhood rashes, such as chickenpox, so the numbering system isn’t used anymore, except for Fifth disease.
At the hospital, Parks, now at 30 weeks, is being monitored closely. She wants other pregnant women to be aware of the virus and get tested if they have been exposed.
“It has been truly the most difficult experience to go through,” Parks said. “He wasn’t guaranteed to come through the fetal anemia.”
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