Incidence of benign convulsions with mild gastroenteritis after introduction of rotavirus vaccine.

Background And Purpose: Rotavirus was the most common virus in benign convulsions with mild gastroenteritis (CwG), with an incidence of 40-50%. As rotavirus gastroenteritis has decreased since introduction of rotavirus vaccine, we investigated the incidence of CwG and rotavirus positivity after introduction of the vaccine.

Methods: We retrospectively reviewed the medical records of 987 patients aged between 3months and 3years who were admitted to the Chonnam National University Hospital between March 2005 and February 2014 due to their first seizures and enrolled 102 patients with CwG. The incidences of CwG among seizure patients and stool rotavirus positivity in CwG patients were compared between two periods: period I (March 2005-February 2010) and period II (March 2010-February 2014). Other viruses in stools were also reviewed.

Results: The incidence of CwG were 8.47% (45 among 531 patients) in period I and 12.50% (57 among 456 patients) in period II (P=0.018). Stool rotavirus was checked in 85.29% (87 patients): 82.22% (37 patients) in period I and 87.72% (50 patients) in period II (P=0.166). The positivity of rotavirus was 40.54% (15 patients) in period I and 16.00% (8 patients) in period II (P=0.01). In the patients without rotavirus gastroenteritis, 30 patients were test for other viruses. Norovirus was the most common (56.67%, 17 patients) and was more frequent in period II than I (71.43% versus 22.22%, P=0.018).

Conclusion: After introduction of rotavirus vaccine, rotavirus-associated CwG has decreased but the incidence of CwG has increased due to an increase of norovirus.