Seventy young adults are being investigated for COVID-19 exposure after taking a chartered plane to Cabo San Lucas, Mexico, for spring break roughly 10 days ago, Austin Public Health says.

Of those 70, 28 have tested positive for COVID-19, and dozens are under investigation by the public health authority; four had no symptoms.

The individuals in their 20s flew out together, then took separate flights back, which allowed for the spread of the virus, APH said in an announcement Tuesday morning.

APH and UT Health, along with University Health Services, tracked down the affected travelers using flight manifests, and APH says those who tested positive are self-isolating.

J.B. Bird, director of media relations for UT Austin, told KUT the 28 patients who tested positive for COVID-19 are UT students, adding that the university is working with APH to assist in contact tracing efforts.

"The incident is a reminder of the vital importance of taking seriously the warnings of public health authorities on the risks of becoming infected with COVID-19 and spreading it to others," Bird said.

The health authority says it has notified the Texas Department of State Health Services about the cases.

As of Monday, two people in Austin-Travis County had died of COVID-19 and 206 people had been infected with the disease caused by the new coronavirus.

Roughly half of those positive cases are of people between the ages of 20 and 40, per Austin Public Health's calculation. That share of cases presents a problem for the roughly 10% of Austinites who are over 65 and more susceptible to the respiratory illness caused by COVID-19.

But health officials said Tuesday it's "dangerously misguided for young and healthy individuals to believe that they won't suffer severe symptoms" of COVID-19, as roughly a fifth of national hospitalizations have been of individuals between 20 and 44.

Got a tip? Email Andrew Weber at aweber@kut.org. Follow him on Twitter @England_Weber.

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