On Monday, May 4, 1970, a few students at the Willis School — a junior high in Delaware, Ohio — felt hot and headachy, with sore throats. Their chests hurt. Over the course of the week, the mysterious ailment hit 40 percent of the school’s 960 students. On Friday the principal closed the school.
The Department of Health investigated, finding no water contamination and no viruses or bacteria in 18 throat swabs. The health officials called the CDC. EIS officer Alan Brodsky arrived on May 25. When interviews of the 40 sickest students didn’t yield a hypothesis, Brodsky developed a questionnaire for all who used the building. He also sent blood samples from 200 randomly selected students back to the CDC labs for antibody testing.
The questionnaire revealed that students became ill whether they ate the cafeteria food or brought their own lunches, rode the bus or walked to school. The high school and nearby Ohio Wesleyan University had no epidemic. The illness rates in the classrooms were relatively uniform.
Brodsky reasoned that the disease was probably airborne. The CDC sent EIS officer Matt Loewenstein to help. He asked whether there had there been any special activities. No. Well, wait a minute, there was Earth Day. On that day, the children were assigned different clean-up tasks, including raking and sweeping up debris around the school building.
Maybe it’s histoplasmosis, thought Loewenstein.· Maybe the students had stirred up histo spores, which grew best in bird droppings. Loewenstein questioned veteran teachers. Why, yes, there had been flocks of starlings perched in the trees that once shaded the school’s courtyard. Bird droppings were so thick that the trees looked like they were covered in snow. The damaged trees were long gone, but the rotted bird droppings remained.
The students had raked the courtyard adjacent to the kitchen and cafeteria around lunchtime. On that hot day, the kitchen staff had reversed the exhaust fans to blow fresh air in, along with the invisible spores, so that anyone eating in the cafeteria breathed them. Then the air circulated through both buildings. The results from the CDC lab revealed that histoplasmosis antibodies were in the blood samples.
It was ironic, wrote the EIS officers, that “as a result of a well-meant attempt at cleaning up the environment, the largest number of clinical cases of histoplasmosis ever reported in a single epidemic occurred.”
BONUS: Brodsky and his colleagues published an account of this in a medical journal: Brodsky, Alan L. et al, “Outbreak of Histoplasmosis Associated with 1970 Earth Day Activities,” American Journal of Medicine, v. 54, March 1973, p. 333-342
BONUS: Another Earth Day odd fact: The Earth Day organization’s web site does not explicitly tell you the date of Earth Day — not unless you delve deep into the site and root around. Earth Day usually occurs on April 22.