BOSTON (CBS) – The Centers for Disease Control has put out a warning about RSV or respiratory syncytial virus. Doctors say RSV can mimic the symptoms of the flu or a cold, but for some people, it can be much more serious.

For three month old baby Stella, it all began with a cough, but after a while things didn’t seem to get better.

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“The first couple of nights, we didn’t get a whole lot of sleep,” said Stella’s mom. She took Stella to the doctor and found out she had RSV, a virus that impacts everyone especially very young and older people.

“They can be hospitalized for it there’s obviously deaths that can occur, so yeah it’s really scary,” Stella’s mom said.

This is peak season for RSV and this week the CDC issued a warning about the virus.

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“The symptoms are often times cough, sneezing, low grade fever,” said Dr. Oren Mechanic of Beth Israel Deaconess Medical Center. He says RSV can be serious for certain segments of the population.

“Those that are under the age of six months, may have been premature or have congenital cardiac or lung problems may be at the greatest risk of having complications from RSV,” Dr. Mechanic said. “Those that are older adults, maybe over the age of 65, may be at risk for complications from RSV as well.”

The CDC says most people recover in a week or two. There’s no vaccine yet but the doctor says we can take action to prevent it.

“This can last on objects for quite some time so if you do use your hands wash them often, try to disinfect things around the house that may have been in contact with sneezing or coughing,” Dr. Mechanic said.

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The CDC says RSV is the most common cause of pneumonia in children younger than one. Cases usually occur in the fall, winter and spring.