The Houston Department of Health is investigating an outbreak of whooping cough at a Memorial Park area school following the confirmation of three cases there.

St. Theresa Catholic School, which enrolls students from three years of age through eighth grade, closed early for the holidays Nov. 12 “out of an abundance of caution,” the Archdiocese of Galveston-Houston said in a statement last week. It will reopen Jan. 6.

In a tweet Wednesday, the health department noted that the confirmation of cases at St. Theresa constitutes an outbreak and said they’re working with campus officials to implement measures to prevent the outbreak’s further spread. The tweet said the closure was voluntary.

Whooping cough, named after the “whoop” sound children make when trying to breathe during a severe coughing spell, is a highly contagious bacterial disease. Though it can be fatal in infants, whooping cough is typically milder than the flu in older children and adults. It can be hard on youngsters’ developing lungs.

Related: Parents should be on the lookout for sounds, symptoms of whooping cough

The illness starts with such symptoms as a runny or stuffed-up nose, sneezing, mild cough and a pause in breathing, then develops into more severe coughing. The archdiocese’s letter urges anyone in contact with St. Theresa students to contact their doctor if they exhibit the first symptoms.

The archdiocese letter said that all of St. Theresa’s students are vaccinated against the infection, also known as pertussis.

The last school outbreak in Houston was during the 2015-2016, a health department spokesman said Wednesday. In that instance, there were no serious adverse outcomes and the school didn’t close.

Houston had 36 cases of whooping cough in 2018 and 30 so far in 2019.

todd.ackerman@chron.com

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