Updated

Some health care providers make a mistake when giving the rotavirus vaccine to babies, injecting the vaccine as a shot instead of placing drops in the infant's mouth as is required, a new report finds.

Between 2006 and 2013, there were 39 reports of the rotavirus vaccine being administered as a shot, according to the publication, from the Centers for Disease Control and Prevention.

In six cases, a nurse who did not receive proper training administered the shots, the report said. In about 50 percent of cases, the child experienced a side effect from the vaccination error, including redness at the injection site. [5 Dangerous Vaccination Myths]

The reasons people made the error included inadequate training, misinterpreting or failing to read vaccine instructions, and confusing the vaccine vial with one used for an injectable vaccine, the report said.

The rotavirus vaccine, which was introduced in the United States in 2006, protects against a stomach bug that can cause severe diarrhea. Before the vaccine, 20 to 60 children younger than age 5 died yearly from the infection, and 55,000 to 70,000 were hospitalized every year, according to the CDC.

The vaccine is one of the few infant vaccines designed to be delivered by mouth (orally). An injected dose is not considered a valid dose, the report said.

"Vaccination providers should follow instructions in package inserts regarding proper administration," the report said. "Administration errors are largely preventable with proper education and training."

Since such mistakes can go unreported, the study likely underestimates the number of rotavirus vaccination errors, the researchers said. Still, with about 55 million doses of the vaccine delivered so far, "these incidents appear to be rare," the report said.

The report also notes the potential danger of getting the vaccine in the child's or someone else's eyes. In 27 cases, the report states, the provider attempted to deliver the vaccine orally as directed, but the vaccine splashed in someone's eye. In 18 of these cases, the infants coughed, sneezed, or spit the vaccine into the eyes of either the provider or the child's parents, and in three cases, infants splashed the vaccine into their own eyes, the report said.

"Vaccination providers should be aware of the potential for eye splashes. Vaccine should be administered gently inside the cheek to minimize coughing, sneezing and spitting," the report said. But when an infant spits out the vaccine, the child does not need a replacement dose, the researchers said.

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