In San Antonio, pediatric cases of respiratory syncytial virus began to increase over the summer. This was unusually early, according to Dr. Pedro Nelson Chavez, the pediatric intensive care unit director at Baptist Children’s Hospital.

RSV season varies annually, but case activity typically increases in Texas around September or October and peaks in December or January, according to the Texas Department of State Health Services. This year, cases began to surge as early as October across the state.

Anyone can be infected with and spread the virus, but very young children—newborns to 2-year-olds—are more likely to experience more severe symptoms, including bronchiolitis and pneumonia, the DSHS reported.

Data collected by the DSHS shows that RSV cases reached a peak between Oct. 8-21. Case counts have declined since then, but medical officials do not know if cases will continue to fall or if Texas will experience another spike this winter.

Chavez said the early spike took many people by surprise.

In Bexar County and Upper South Texas, over 200 positive RSV cases were recorded during the week of Nov. 12, which was the latest data available at the time of publication. Physicians are not required to report RSV cases to the state, so case levels are likely higher than the data shows.

Around the same time last year, fewer than half as many cases were reported in Upper South Texas. Data shows just under 100 positive RSV cases were reported during the week of Nov. 13, 2021.

Although RSV cases have declined since mid-October, Chavez said the situation is “still pretty critical.”

“We are OK today, but I don’t know what’s going to happen tonight,” Chavez said.

He said Baptist Children’s Hospital regularly accepts children from other parts of the state if their local hospitals do not have the capacity to care for them.

To prevent the spread of RSV, Chavez emphasized avoiding contact with sick people. This is especially important for babies and young children, he said, as they are more susceptible to the virus.

He also recommended frequent hand-washing, wearing masks and avoiding large gatherings.

According to the DSHS, symptoms of RSV are similar to other respiratory infections. For older children and adults, symptoms include a mild fever, congestion/runny nose, cough and sore throat, headache, fatigue and occasional wheezing. Children younger than 2 are more likely to experience severe symptoms, such as bronchiolitis and pneumonia, a cough with a “barking” sound, rapid or difficulty breathing, middle ear infections, and bluish lips or fingernails.

RSV symptoms typically appear within four to six days after contracting the virus, according to the DSHS.

Infants and premature babies are more likely to have severe RSV symptoms, according to UT Health Austin. Children who have asthma, an underlying lung disease, congenital heart disease, Down syndrome or other immunocompromising conditions may be at high risk from RSV.

Influenza also hit Texas earlier this year, according to state health officials. Flu cases in Texas and other parts of the Southern United States were at “very high” levels in early November.