Rotavirus vaccine leads to substantial decline in cases

While the safety of vaccines remains debated in some circles, a new report highlights the value of vaccination, particularly for rotavirus.

Since the rotavirus vaccine was introduced in 2006, cases of the disease-which causes serious and sometimes fatal gastroenteritis, particularly in infants-have plummeted, according to a new report from the Centers for Disease Control and Prevention (CDC).

“This study demonstrates that rotavirus vaccine has significantly reduced the burden and modified the seasonality of rotavirus disease in the United States,” says lead author Ben Hallowell, PHD, MPH, an Epidemic Intelligence Service Officer for the CDC”s National Center for Immunization and Respiratory Diseases, Division of Viral Diseases.

Two rotavirus vaccines are currently recommended by the CDC, and both are given orally in the first few months of life, with the series completed by age 8 months.

Changing history

Rotavirus was the leading cause of severe gastroenteritis in children prior to the vaccine’s introduction in 2006, and the new report analyzed disease prevalence since the vaccine’s introduction. The CDC collected prevaccine data from 2000 to 2006 and postvaccine data from 2007 to 2018, and found that the annual percentage of tests that were positive for rotavirus declined from 25.6% in the prevaccine period to 6.1% in the postvaccine period,¹ according to the research.

Additionally, annual peak positivity decreased from 43.1% in the prevaccine period to 14% in the postvaccine period, and season duration decreased from 26 weeks in the prevaccine period to 9 weeks in the postvaccine period.

The study concluded that the vaccine has substantially decreased the burden of disease for rotavirus, even with coverage plateauing at about 70% nationwide.

Even with the success of the vaccine, however, the study revealed a biennial disease pattern with alternating years of high and low virus activity, Hallowell says.

“While we do not know the exact cause of this biennial pattern, we do know that this pattern is not observed in other countries with higher vaccination rates,” he says. “If we improve vaccine coverage and on-time vaccinations, we will prevent additional rotavirus cases and may be able to eliminate this biennial seasonal pattern.”

The CDC notes that it takes a team effort from all providers and nonclinical staff to improve vaccination rates and support parents in vaccine decision-making. Hallowell says he hopes the study will help clinicians continue to improve vaccination rates and further reduce the burden of this disease, which claims more than 200,000 lives across the globe each year.

“This work demonstrates that rotavirus vaccination has dramatically reduced US disease burden and altered seasonal patterns,” Hallowell says. “Hopefully, this evidence will further encourage healthcare providers to continue to improve coverage and on-time rotavirus vaccination.”