A probable enterovirus outbreak is sending hundreds of children to the hospitals in the Midwest and Southern United States. Experts suspect enterovirus D68 (EV-D68), an uncommon strain of enterovirus, as the culprit.

Here's what you need to know about the virus and what you can do to protect yourself and your family from getting infected.

What are enteroviruses?

Enteroviruses are a large family of viruses that is responsible for many infections in children. There are more than 150 different strains of enteroviruses, causing about 10 to 15 million infections in the U.S. each year, according to the Centers for Disease Control and Prevention. People infected with the virus usually don't get sick or show mild cold-like symptoms, if they do get sick at all.

What is Enterovirus D68?

Enterovirus D68 is an uncommon strain of the enterovirus. It was first identified in 1962 in California and it was rarely reported since that time. However, it's possible that its has the low number of reports, because the strain is not frequently identified, according to Mark Pallansch, a virologist and director of the Viral Diseases Division at the CDC.

What are the symptoms of an EV-D68 infection?

EV-D68 infected patients show symptoms of mild to severe respiratory illness with little or no accompanying typical symptoms of a viral infection.

Only 25% to 30% of our kids have fever, so a vast majority don't.

Instead, kids with D68 infections have cough and trouble breathing, sometimes with wheezing," described Dr. Mary Anne Jackson, division director of infectious disease at Children's Mercy Hospital in Kansas City, MO, the hospital where the first cases of EV-D68 infections were identified.

"They act like they have asthma, even if they don't have a history of it, "adds Jackson. "They're just not moving air."

Why is there an increase in some reported cases?

According to the CDC, the usually enterovirus season runs through summer and fall. However, this virus hasn't spread widely throughout the U.S. before. Jackson explains that people are most likely to become susceptible with any new virus that was not widely circulated.

The spread of the virus also coincided with the opening of schools and start of a new school year.

How is EV-D68 transmitted?

The EV-D68 virus is found in an infected person's saliva, nasal mucus or sputum, according to the CDC. A person usually gets infected by touching a contaminated surface or object and then rubbing their eyes or nose without washing their hands. A person can also get infected through close contact, such as shaking hands, with an infected person.

Who is at-risk of EV-D68 infection?

While anybody can get infected, infants, children and teenagers are at greater risk because they have not yet developed an immunity against the viruses. The CDC reports that most cases involved children aged 6 months to 16 years, with most cases involving children aged 4 and 5 years.

The virus is particularly hitting hard those children with breathing problems. Jackson cites that two-thirds of their patients at Children's Mercy had a history of asthma or wheezing.

How is EV-D68 infection treated?

The CDC says that there is no specific treatment for EV-D68 infections. Antibiotics aren't an option, because the infection is caused by a virus, not a bacteria. Nonetheless, many of the EV-D68 infections will be mild and self-limited, requiring only treatment of the symptoms.

Some patients with severe respiratory illness may require hospitalization to receive supportive therapeutic care. According to pediatrician Roya Samuels at the Steven and Alexandra Cohen Children's Medical Center in New Hayed Park, N.Y., the child should be brought to the doctor's clinic or emergency room if the child has rapid and/or labored breathing, wheezing or if the skin is pulled in between the ribs or above the collarbone.

How is EV-D68 infection prevented?

There are no vaccines against EV-D68 infections. However, you can take the following steps recommended by the CDC to reduce the risk of infection.

  • Regularly wash hands with soap and water for 20 seconds, especially after changing diapers or after going to the toilet.

  • Avoid touching your eyes, nose and mouth without washing your hands.

  • Regularly clean and disinfect frequently touched surfaces, such as toys, the telephone and doorknobs, especially when someone is sick.

  • Avoid close contact, like kissing and hugging, with people who are sick.