Dual vaccine targets norovirus

May 09, 2023 | Biotechnology

Norovirus causes numerous cases of food poisoning, especially in children. The incidence rate continues because of a lack of ways to control it. Human norovirus stymied efforts as it doesn’t infect lab animals, thus affecting the development and replication of rotavirus vaccines with norovirus.

A research from the Washington University of Medicine in St. Louis created a vaccine against norovirus by piggybacking on the effective vaccines for rotavirus, an unrelated virus that causes diarrhea. Rotavirus vaccines are effective and are already in global distribution, with 4 of its live-virus vaccines used around the world. This novel approach is especially beneficial to kids in developing countries where there isn’t access to clean water and where cases of norovirus can be deadly.

The addition of a key protein from norovirus to a harmless strain of rotavirus enabled the team to assemble an experimental rotavirus-norovirus combo vaccine. This bypasses the technical difficulties encountered in working with norovirus. In their animal model, the immunocompromised mice that received the vaccine by mouth produced neutralizing antibodies against both viruses.

The team took blood and fecal samples during the 4th, 6th, and 8th week. Nine weeks after the initial immunization, they gave the mice a booster by injection and took samples a week later.

The blood of nine out of 11 mice showed strong antibody response. it was present in the intestines of all 11 mice. Mini-gut cultures or organoids, which replicate the surface of the human gut, witnessed how these antibodies were able to neutralize both viruses.

Further experiments to show how immunized animals from these dual vaccines will be less likely to get sick or die from norovirus is still underway. This study foresees rapid vaccine development for various troublesome organisms in resource-limited environments, like in the developing world where many infections occur.