As part of their routine well child visits baby Jose and baby Stanislav will be getting immunizations.
Those include a rotavirus vaccine, available since 2006. It protects against a virulent form of diarrhea.
"Bad diarrhea means two to twelve stools within 24 hours. It often lasts for several days. These kids may need to go in the hospital. They certainly need oral rehydration and often intravenous rehydration," explained Dr. Janet Englund.
Seattle Children's Pediatrician Dr. Englund is a Professor of Pediatrics at the University of Washington. She's part of a team tracking the disease across the country.
"We are finding an incredibly decreased amount of rotavirus this year compared to four years ago. We are finding the vaccine is very effective. But we are still finding rotavirus in kids who haven't been vaccinated," she said.
Some parents may opt out because rotavirus vaccines had a rocky start. An early version was pulled off the market in 1999, after it was linked to a rare but dangerous intestinal blockage called intussusception. Untreated, it can be life threatening.
Researchers led by Irene Shui, ScD from the Department of Epidemiology, Harvard School of Public Health, poured through nearly 800,000 records of Rotateq, the new vaccine given to babies from May 2006 to February 2010.
"Because the rotavirus vaccine is given to almost every child in the United States, it's crucial to monitor the vaccine's safety," said Dr. Shui.
Their findings were just released in the Journal of the American Medical Association.
"Our study did not find an increased risk of intussusception following the rotavirus vaccine," said Dr. Shui.
It's good news for babies, and for pediatricians.
"We want this data to present to our patients and say this is a good vaccine. We already thought it was. But now we have a lot more proof," explained Dr. Englund.
Still, she said, no vaccine can protect against all cases of diarrhea.
"I think it's really important if your baby can't take in more than he or she is pooping out, then that's when you need to call the doctor," she said. Seattle Children's has more information on their website to help parents decide when to call the doctor.
Dr. Englund also reminded parents the vaccine isn't recommended for children older than infants, saying older kids and adults don't get as sick as babies do from rotavirus.