A new rotavirus vaccine has significantly decreased the number of children hospitalized for rotavirus-related diarrhea.
"We looked at the impact of the vaccine over four consecutive vaccine years," lead author Dr. Eyal Leshem of the Centers for Disease Control and Prevention (CDC) in Atlanta, told Reuters. "The dramatic decline we saw at the beginning has continued."
Rotavirus kills between 20 and 60 children a year, Reuters reported.
"Worldwide, about 450,000 children died each year due to rotavirus before a vaccine was licensed," Doctor Evan Anderson, who studies rotavirus infection at Emory University School of Medicine in Atlanta, told Reuters.
"The virus is spread by contact with infected stool, usually by fecal-oral transmission, and it is incredibly infectious," Anderson said. "About 10 billion viral particles exist in a gram of stool and only about 100 are needed to cause infection."
The rotavirus vaccine was originally introduced in 1998, but was taken from the shelves because medical researchers were concerned it could cause blockage in babies' bowels.
In 2006 the U.S. Advisory Committee on Immunization Practices recommended that all children get vaccinated for the illness after new vaccines were introduced. By 2010, 78 percent of children under the age of one in the U.S. had been vaccinated.
These new vaccines have not appeared to have the same bowel-related side effects.
The researchers believe the virus has prevented "177,000 hospitalizations, 242,000 emergency room visits and more than a million outpatient visits for diarrhea among children under age five," Reuters reported.
Cases of rotavirus hospitalizations fell by 75 percent in 2007 and stayed relatively constant through 2011.
"One of the interesting findings we had was in one of the later years we saw a 94 percent decrease in hospitalization; rotavirus had practically disappeared in 2010," Leshem said. "This is attributed to good vaccine effectiveness and high coverage."
The vaccination rate for rotavirus is still much lower than many other vaccines.
"Unfortunately, there is a limited window during infancy for receiving the vaccine so a number of children are not able to receive the vaccine or are not completely vaccinated," Anderson told Reuters.
