HOUSTON -- Samuel Guerrero was less than two weeks old when his mother Tracy Gutierrez noticed him struggling to breathe.
"He was coughing, and he had a lot of congestion, and he was breathing pretty fast," said Gutierrez.
Doctors diagnosed the newborn with RSV - or respiratory syncytial virus, which attacks the lungs and breathing passages.
While most cases are mild, each year up to 175,000 children under 5 are hospitalized. And there are an estimated 100 to 500 pediatric deaths.
Premature babies and those with lung or heart problems are at greatest risk for severe illness. Samuel was born with a heart defect. "I was even more concerned because he does have his heart condition, so I was like, even more worried about him," said Gutierrez.
Infectious diseases doctor, Jeffrey Starke, does not know the reason for the increase and says there's no drug treat it. He said, "This is happening in our area at the same time that influenza is happening, so we have the sort of bad storm of both of those infections...and in little babies it's hard to tell the difference between them."