In October 1978, the College experienced a series of Salmonella outbreaks which startled both students and administrators, catching University Health Services (UHS) off guard and ultimately threatening to cripple interhouse dining policies.

On Oct. 16, 1978, UHS was first alerted of Salmonella poisoning on campus, when eight students were diagnosed with the illness. Three of the cases were serious enough to warrant admittance into Stillman Infirmary for treatment.

Then-UHS Assistant Director Dr. Sholem Postel said at the time that Salmonella infects mainly dairy products, especially food made with eggs. Diarrhea is the main symptom of such poisoning—in fall 1978, students would nickname the Salmonella outbreak the “Harvard trots.”

According the U.S. Center for Disease Control (CDC), Salmonella bacteria usually resides within human and animal intestines and are transmitted by eating foods contaminated with feces or by the unwashed hands of infected food handlers. Contaminated foods look and smell normal, making identification difficult. The illness usually lasts only four to seven days, and most people recover without treatment, according to the CDC.

Because football players and first-years made up the majority of the reported cases during the first outbreak, investigators pinpointed the Freshman Union and the Varsity Club as the most likely dining areas where students could have contracted the infection, according to then-UHS Director Dr. Warren E.C. Wacker.

State Department of Public Health investigators also stepped in to take samples of contaminated foods to confirm the specific species of Salmonella that caused the poisoning. Samples were also taken from kitchen staff and students who worked in the Union or the Varsity Club kitchens.

While investigators labored to find Salmonella carriers, on Oct. 28, a week and a half after the first outbreak, eight more students—this time in Winthrop House—were infected.

Although Wacker admitted to only eight positively proven Salmonella poisonings in Winthrop, residents insisted that a much larger number of students were actually sick.

“I went from table to table on Monday asking people if they had salmonella poisoning. I counted 22 people in 15 minutes,” Paula Gardner ’79, a Winthrop resident who contracted the disease, told The Crimson in 1978.

Winthrop resident Paul S. Williams ’81 also told The Crimson then that he and his two roommates all contracted the illness, but only one of the three visited UHS.

At the same time that Salmonella poisoning hit Winthrop, investigators finally found the carrier for Salmonella at the Freshman Union.

“At the Union they isolated it to a man who had been on vacation in Mexico, who was carrying the disease but didn’t feel sick,” said James Koddle, a Salmonella poisoning victim who was treated in Stillman Infirmary for four days.

A third and final outbreak occurred in Kirkland House in early November. In an attempt to isolate the spread of the infection, the College University officials decided to ban all interhouse dining, remove possible carrier foods from salad bars, provide only plastic utensils in certain Houses and suspend the hiring of all temporary employees in the dining halls.

“We believe this is the prudent and correct thing to do at this time. This will not be popular, and I’m sorry for any inconvenience, but my first responsibility is the health of the undergraduates,” then-Dean of the College John B. Fox said.

The decision to ban temporary kitchen workers came a month after Brian F. O’Leary ’79, a Mather House resident who worked in the Union dining hall, wrote a letter to Food Services officials. The letter complained that temporary employees had not been subjected to the same Salmonella testing as regularly-scheduled employees.

Charles J. Krause Jr., UHS sanitary inspector, said that while he had received a copy of O’Leary’s letter, he did not agree that the temporary employees constituted a health hazard.

And Wacker said that the temporary employees were not banned because they were considered health hazards. Rather, he said, it would be impossible to test the temporary employees—who are assigned on a day-to-day basis—because UHS did not receive test results until three days after testing.

Interhouse dining hall restrictions did not last long, and were lifted after about one week.

Wacker said he was very pleased to be able to lift the ban so quickly.

“Even the students at South House, who have been most inconvenienced, have been very good about it,” he said.

In late November, the State Department of Health laboratories identified a salad worker at the Central Kitchen as a potential Salmonella carrier. Krause said that the infected employee was removed temporarily. He also selected specimens of the salad handled by the worker to test for Salmonella.

While they identified some of the possible carriers, UHS officials never found out how Salmonella spread from the Union to Winthrop House. They suspected, however, a student carried the infection, Krause said.

While at the end of November eggs remained off the dining hall menus, at the semester’s close most student employees were allowed to return to their positions, provided that they were cleared by UHS.

“On the basis of this experience, we’re going to reinforce the usual sanitary practices,” Wacker said. “You may as well learn from something like this.”

—Staff writer Risheng Xu can be reached at xu4@fas.harvard.edu.