Atmar RL.N Engl J Med. 2011;365:2178-2187.
Two doses of an intranasal vaccine containing norovirus virus-like
particles significantly reduced the frequencies of both Norwalk
virus-associated infection and illness, according to new findings published in
The New England Journal of Medicine.
“The increasing recognition of noroviruses as causes of disease
and the limited success in preventing outbreaks of illness have led to the
consideration of vaccines as a potential means for disease control,”
Robert L. Atmar, MD, of Baylor College of Medicine, and colleagues wrote
in the study. “This study shows that it may be possible to use a
vaccination strategy to prevent norovirus disease.”
For the double blind, placebo-controlled trial, Atmar and colleagues
evaluated the safety, immunogenicity and efficacy of an investigational
norovirus virus-like particle vaccine to prevent acute viral gastroenteritis
caused by the Norwalk virus.
Robert L. Atmar, MD
Healthy adults (n=98) aged 18 to 50 years were randomly assigned to
receive two doses intranasally 3 weeks apart of either vaccine (n=50), placebo
(n=48) or both (n=90). Participants were then immunized with Norwalk virus and
monitored for infection and gastroenteritis symptoms.
Compared with 69% of those in the placebo-only group, Norwalk virus
gastroenteritis occurred in only 37% of vaccine recipients (P=.006); and
Norwalk virus infection occurred in 82% of placebo recipients vs. 61% of
vaccine recipients (P=.05).
In addition, the researchers observed an increase of 4 in serum antibody
levels among 70% of vaccine recipients. Adverse events were similar between the
groups and included nasal stuffiness, nasal discharge and sneezing.
“This study was a proof-of-principle study to assess whether
vaccination can prevent norovirus infection and illness under ideal
circumstances (healthy adult study population, short interval from completion
of vaccination to exposure to virus, challenge with the same virus strain that
was in the vaccine),” Atmar told Infectious Disease News. “Future
studies will assess whether protection can be increased, how long protection
lasts, and how well the vaccine protects following natural exposure, in other
populations (ie, older adults, children, immunocompromised patients) and
against strains that are different than the one(s) in the vaccine.”
–by Ashley DeNyse
Disclosure: This research was funded by LigoCyte Pharmaceuticals
and the NIH.
Herbert L. DuPont, MD
Noroviruses cause half of all foodborne enteric disease in the United States and an important percentage of waterborne outbreaks. As rotavirus gastroenteritis is controlled by vaccines, noroviruses are likely to take their place as the important causes of pediatric enteric illness. There is no vaccine for this group of viruses. Atmar and colleagues at Baylor College of Medicine have worked to develop a means of possible immunologic control of gastroenteritis due to noroviruses in persons at high-risk using genotype-specific virus-like particles given intranasally to susceptible adults.
- Herbert L. DuPont, MD
Infectious Disease News Editorial Board member
Disclosure: Dr. DuPont reports no relevant financial disclosures.