"Let's say all of a sudden the patient developed a fever and started having chills and feeling really sick … we might conclude in retrospect that it's an abundance of caution, but we have to leave that to the flight crew," he said.
A group of education students from Slippery Rock University in Slippery Rock, Pa., thought their trip to Mexico would help them toward graduation day, not bar them from it.
But after the 22 students and two faculty members returned from their "teaching experience" trip to Mexico City Tuesday, they heard disappointing news from the administration.
"We were getting lots of calls from people asking how could we possibly allow [the returning] people to participate in graduation," said Rita Abent, executive director of public relations at Slippery Rock University.
Abent said parents were concerned about the possibility of infecting young children or those with weakened immune systems.
However, the students did not show flu symptoms.
"We were following the CDC guidelines where if you've been in an area where you could have been exposed [it's recommended] to do some self-social distancing," said Abent.
However, experts in preventive medicine say the quarantined graduation was above and beyond standard public health recommendations.
"That kind of, shall we say over abundance of caution, is not recommended by the CDC or any other group at the present time," said Schaffner.
But as he watched the ceremony on TV this weekend, Schaffner said that the Slippery Rock community seemed to have accepted the choice and had a good time anyways.
Indeed, Abent said some of the students and public health experts were on board with the decision.
"They have made an incredible sacrifice to take themselves out of the commencement ceremony so they do not expose their fellow classmates and 6,000 guests expecting to come," said Abent.
Abent admitted not all the students were happy to oblige the university's decision.
"Initially, when they heard the news, the greatest response was disappointment," Abent said. "Do we have a couple of people who are still very angry? Yes, absolutely."
"No one would say, 'Jeez, this is a great thing,'" Abent said -- but she added that she thought most students' reaction was to make the best of the odd situation.
Abent said the students barred from the full graduation ceremony will have their own separate ceremony, which will be videotaped and played during the time they were supposed to graduate.
Surely the Slippery Rock decision could be debated either way in terms of caution, but some behavior on the borders of the U.S. and Mexico seems downright counterproductive.
The U.S. State Department's travel advisory for Americans may make a lot of sense for a person flying from Missoula to Mexico City.
But take the estimated 1 million people who cross the U.S.-Mexican line at border towns like El Paso-Juarez every day, and some public health measures might begin to sound a little silly.
A tourist from New York at the Tijuana-San Diego border where thousands cross daily, told Agence France Presse that he debated whether to cross into Mexico.