Penn professor talks viruses in children

By Lianna Lazur
Correspondent

Dr. Aimee Richard of the University of Pennsylvania School of Medicine visited the College for a biology colloquium on Thursday, Sept. 19.

Some attendees of the lecture were familiar with Richard from her talk at Triumph Brewery in Princeton over the summer on the process of home brewery and beer tasting.

Richard discusses bacteria. (Photo by Lianna Lazur)

In addition to her postdoctoral research at the University of Pennsylvania School of Medicine, Richard is a nationally acclaimed beer judge. At Thursday’s talk, however, Richard spoke of her recent studies of the host bacterial factors that affect the transmission of the infectious disease Streptococcus pneumoniae.

Stripped down, Streptococcus pneumoniae is a virus that often causes cough and fever in areas with close physical contact, most often in children.

Richard’s initial interest in bacterial infections began with her fascination in respiratory infections known to affect children. Richard began the lecture by bringing up preliminary graphs summarizing the population of children affected by respiratory infections. The amount of affected children was miraculously high due to naturally unavoidable behaviors and the germs they tend to carry and attract.

According to Richard, Streptococcus pneumoniae exists as both a commensal and a pathogen. As a commensal, Richard explained that the infection colonizes the nasopharynx.

“Streptococcus pneumoniae is carried by up to 50 percent of children greater than the age of five years old,” Richard said.

Progressing forward, Richard went into depth taking the audience through her methods of experimentation used to better understand the disease. The subjects of her experimentation were infant mice. With use of Black 6 mice, throughout the course of a 14-day trial period, Richard came to a hypothesized answer to her initial question: “How exactly does influenza co-infection promote transmission?”

Richard explained this could occur due to viral infection increasing the bacterial load or the host response to the influenza affecting the transmission.

Richard used flow cytometry to assess the immune response to infection. She did a combination of four different tests on the infant mice that brought her to the conclusion that innate immune response to influenza infection promotes bacterial transmission.

Richard highlighted a key virulence factor of Streptococcus pneumoniae — the capsule. Throughout the duration of her research, Richard came up with multiple hypotheses which led her to further testing on mice.

Richard is still at practice in her experiment to further decode the medical and scientific conundrum, Streptococcus pneumoniae.