WHO officials have recommended that rotavirus
vaccination be included in all national immunization programs.
The recommendation by WHO’s Strategic Advisory
Group of Experts extends an earlier recommendation made in 2005 on vaccination
in the Americas and Europe, where clinical trials had demonstrated safety and
efficacy in populations with low and intermediate mortality. New data from
several clinical trials in developing countries led to the recommendation for
global use of the vaccine.
Story continues below↓
One clinical trial, funded in part by GAVI and conducted
by PATH, WHO, GlaxoSmithKline and research institutions in high-mortality,
low-socioeconomic settings of South Africa and Malawi, found that the vaccine
significantly reduced severe diarrhea episodes due to rotavirus.
While efficacy data from Asian countries are
forthcoming, SAGE recommended rotavirus vaccines for all populations, including
Asia, since available evidence indicates that efficacy data can be extrapolated
to populations with similar mortality patterns regardless of geographic
location.
“The GAVI Alliance welcomes this exciting
recommendation,” GAVI CEO Julian Lob-Levyt said in a press release.
“It represents another important step in our ability to achieve
significant impact on under-5 deaths in the world’s poorest communities
and make progress toward the Millennium Development Goals. We are extremely
excited about the potential to offer African and Asian countries funding to
introduce rotavirus vaccines.”
CDC researchers writing in the Journal of the
American Medical Association this week noted reductions in severe rotavirus
diarrhea rates in Nicaragua following routine use of the pentavalent rotavirus
vaccine there.
In October of 2006, the Nicaraguan Ministry of Health
added the vaccine to the immunization schedule. The schedule recommends
recommending three doses of RV5 for all children between the ages of 2 and 6
months.
Children in four hospitals, in Managua, Jinotepe, Masaya
and Matagalpa, Nicaragua were evaluated, as well as all age-eligible children
to receive the vaccine who were admitted for confirmed cases of rotavirus
diarrhea. CDC researchers selected one to three neighborhood and hospital
controls for each patient.
About 1,600 patients provided stool samples, of which
285 were identified with a single rotavirus strain. Two-hundred fifty one
children received intravenous hydration and 265 were admitted for about three
days. “Of all the cases and controls, 18% and 12% respectively, had not
been vaccinated. 12% and 15% received one dose of RV5, 15% and 17% received two
doses, and 55% and 57% received three doses,” the researchers wrote.
The researchers concluded children who were administered
three doses of RV5 had a lower risk of rotavirus diarrhea that required
overnight hospitalization or intravenous hydration. They also noted an
increasingly lower risk of severe and very severe rotavirus diarrhea following
RV5 vaccination.
The CDC researchers noted that although vaccination
reduced the risk of severe rotavirus diarrhea in children younger than 2, it
was not to the same extent as has been reported in clinical trials in
industrialized nations.
WER. 2009, 84:213–236
JAMA. 2009;301(21):2243-2251.
