Scientists study spread of flu across college campuses

Getting sick with the flu can disrupt your entire schedule. Yet sick students still regularly show up to class, work, and meetings, potentially putting everyone around them at risk for illness. You might find yourself heading to the doctor’s office because of a classmate — or was it your roommate? Or your teaching assistant? Or someone you sat next to on the bus?

When viruses are going around campus, it can be hard to tell who was to blame, especially if many people are sick at the same time. But what if you could pinpoint who gave you the virus?

A research study called “Characterizing and Tracking College Health: The Virus Study” — known as C.A.T.C.H. The Virus — is trying to make that possible by tracking how the flu spreads from student to student on campus at the University of Maryland.

But the researchers aren’t tracking virus transmission so that students can identify and get revenge on whoever got them sick — they’re trying to learn more about how and why viruses spread within a population.
The researchers, led by environmental and occupational health researcher Donald Milton, are building up a pool of data from sick students,through collecting blood, snot, and breath samples from sick students.

The first two types of sample are relatively easy to collect. To get the breath samples, the researchers have to seat the students in a special booth (called the Gesundheit-II), and have them put their face in a cone, which they breathe into for half an hour.

They have also installed carbon dioxide-sensitive instruments in dormitories that measure how much of the air has been exhaled by a person.

The researchers are interested in gathering data on a number of viruses, but they’re most focused on the flu.
“Flu is important to everybody,” says Milton. This year’s flu season is the worst in the past 13 years, according to the Center for Disease Control.

Viruses mutate fairly quickly as they’re passed around campus. By tracking the people sick students have interacted with and the genetic changes within the virus samples, the researchers will try to “establish who infected whom, and where, and how,” Milton says.

Flu viruses spread in a few different ways — by touch, by large droplets that have been coughed or sneezed out of someone’s lungs onto a surface like a desk, and by smaller droplets called aerosols, which hang around in the air after being coughed or sneezed out.

But it’s unknown how much each transmission method contributes to viral spread.

The aerosol particles are the area of most interest, because they can’t be controlled by washing your hands or sterilizing a surface, instead remaining suspended in the air.

“This could mean that just having good cough and sneeze etiquette — sneezing or coughing into tissues — may not be enough to limit the spread of influenza,” says virologist Andrew Pekosz of Johns Hopkins University. “Just sitting in your office and breathing could fill the air with infectious influenza.”

But they won’t know for sure how much that factors in until the study, which has been ongoing since November, finishes. “If we don’t understand how [viruses] are transmitted, it’s hard to come up with policies that are really going to work,” Milton says.

This year’s flu hasn’t hit the University of Maryland dormitories yet, but the researchers are expecting to get a lot of data when it does.

“Once one person gets sick, it goes around to everyone on the floor,” says sophomore Parker Kleb, a research assistant on the study. “I’m very interested to see what happens in the next few weeks, and how the study will hopefully benefit.”