Tuesday, January 13, 2015

Study shows vaccination decreases rotavirus rates

Baylor College. US: A new study by Baylor College of Medicine and Texas Children’s Hospital researchers shows that a vaccine for rotavirus in infants reduces the rates of infection. In the study of children enrolled in an acute gastroenteritis (AGE) surveillance program, researchers found that healthcare providers who administered rotavirus vaccines to more of their patients saw lower rates of rotavirus infection than those who did not. Their report appears today in the journal Pediatrics.
“This shows that there is an association between not being vaccinated and getting the disease,” said Leila Sahni, immunization action plan coordinator at Texas Children’s and first author of the paper.
Rotavirus is a common case of childhood diarrhea and vomiting and a major cause of mortality in middle and low-income countries. Rotavirus vaccines were first introduced in the United States in 2006 and have a narrow age range during which they can be given. Infants must receive the first dose of this oral vaccine at their two-month visit. Researchers at Baylor and Texas Children’s have been monitoring patients who arrive at the Texas Children’s emergency center with AGE and noticed that a high proportion of rotavirus-positive cases were occurring among patients from a small number of individual provider locations.
They hypothesized that the vaccination coverage rates at these sites might be associated with the proportion of rotavirus-positive cases from that provider location.
Over a two-year period, researchers reviewed vaccination records for infants who came into the emergency room with AGE and determined which providers in the city had low coverage (less than 40 percent), medium coverage (40 to 79 percent) or high coverage (80 percent or more) for the rotavirus vaccine amongst their patients. They found that a little over 80 percent of patients in the surveillance program had received the rotavirus vaccine from 68 different locations. Of these locations, four locations were classified as low coverage, 22 were medium coverage and 42 were high coverage for the vaccine. Patients cared for by pediatricians at low-coverage locations had 31.4 percent of all rotavirus-positive patients compared to 13.1 percent and 9.6 percent in the medium and high-coverage locations, respectively. Patients from low-coverage locations were 3 times more likely to have rotavirus than patients from high-coverage locations
Of the four low-coverage locations, one was a neonatal intensive care unit, or NICU. The rotavirus vaccine is not administered in NICUs because it is a live vaccine that is given orally. The vaccine is not given to premature infants, and some remain in the NICU for the entire window during which the first dose of vaccine can be administered (up to 14 weeks and six days). Those infants who are discharged from the NICU before this time can receive the vaccine upon discharge.
Sahni notes the importance of providers administering this vaccine during the two-month visit and for parents to be aware of it.
“It’s the only vaccine that is given by mouth, so parents should ask about it during the two-month visit if they notice that their child did not receive it,” said Sahni.
Others who took part in the study include Dr. Julie A. Boom of Baylor and Texas Children’s and Dr. Jacqueline E. Tate, Dr. Daniel C. Payne and Dr. Umesh D. Parashar of the Centers for Disease Control and Prevention.
The study was supported by a Centers for Disease Control and Prevention grant awarded to the Texas Department of State Health Services (CDC-RFA-CI07-70405ARRA09).