On Wednesday, a woman gave birth in a Lubbock, Texas hospital in the middle of a deadly and fast-growing measles outbreak. Doctors didn’t realize until the young mother had been admitted and in labor that she herself was infected with the measles.

By that time, other new moms, newborn babies and their families at University Medical Center Children’s Hospital in Lubbock had unknowingly been exposed to the virus, considered one of the most contagious in the world.

Hospital staff are scrambling with damage control efforts — implementing emergency masking policies and giving babies as young as three days old injections of immunoglobulin, an antibody that helps their fragile immune system fight off infections.

A 2021 study found that the therapy is highly effective in protecting exposed newborns from getting sick.

“These babies didn’t ask for this exposure,” said Chad Curry, training chief for the University Medical Center EMS. “But at the end of the day, this is the only way we can protect them.”

Neither Curry nor UMC representatives could give an exact number of exposed newborns.

It’s unclear when the woman tested positive for measles. Public health officials are casting a wide net in an effort to contact everyone who may have been exposed to this particular patient. Viral particles can live in the air or on surfaces for up to two hours.

It’s a setback for public health officials on the front lines trying to stop the escalating outbreak.

At the end of last week, Katherine Wells, director of public health for Lubbock’s health department, said she felt like the outbreak was beginning to be controlled. At the time, cases seemed to have peaked. Doctors offices had become savvy at making sure patients likely to have a measles exposure steered clear of other patients.

This new development, she said in an interview Friday, “feels like we’re back to square one.”