Enabling smarter vaccines to save children’s lives

Sarah McDonald

Patrick Beeson

Sarah McDonald studies rotavirus, which kills more than 500,000 children in the developing world each year.

Infection with rotavirus, a highly contagious virus named for its resemblance to the radiating spokes of a wheel, is often little more than an unpleasant childhood rite of passage in the United States. In the developing world, though, the virus causes a severely dehydrating diarrhea, each year killing more than 500,000 children under the age of five and forcing the hospitalization of millions more.

In 2006, two rotavirus vaccines became widely available, and pediatricians across the United States and Europe began administering them as part of routine infant immunizations. While those vaccines have achieved success rates of 85 to 90 percent in this country, in the developing world, the success rate can drop to as low as 10 percent.

To Sarah McDonald, PhD, an assistant professor in the Virginia Tech Carilion Research Institute, that percentage is unacceptable.

“It’s tragic enough that so few children in the developing world have access to a rotavirus vaccine,” McDonald says. “But the low effectiveness makes their burden that much heavier.”

Even for children in the United States, McDonald adds, a key question remains: Will new rotavirus strains emerge, compromising the vaccines’ power to protect them? “Viruses mutate,” she says, “and just as scientists need to reformulate flu vaccines, we’ll need to consider tweaks to existing rotavirus vaccines.”

Through her research, McDonald seeks to provide a scientific foundation for vaccine and antiviral design, allowing more targeted approaches to rotavirus. In particular, her laboratory at VTCRI will use large-scale nucleotide sequencing to define the level of genetic diversity among circulating strains of the virus before and after vaccination. In collaboration with Carilion Clinic pediatricians, she will characterize viral strains from vaccinated children admitted to Roanoke hospitals. She will also analyze clinical specimens from international collaborators. These avenues of research will help her compare rotavirus strains in the local community with those in the developing world.

“Dr. McDonald’s research is extremely important in helping to provide a scientific underpinning for the design of next-generation vaccines,” says Michael Friedlander, PhD, executive director of VTCRI. “Her work will allow us to keep one step ahead of this deadly virus.”

“We’re very fortunate to have attracted Dr. McDonald to Roanoke from the National Institutes of Health,” Friedlander adds. “She offers a major new molecular virology research dimension to the VTCRI and to an already strong clinical program in pediatric infectious diseases at Carilion.”