Detection of Rotarix Vaccine Viruses in Older Children with Acute Gastroenteritis, Northwest Ethiopia

Abstract

Background: In 2013, Ethiopia introduced in its national routine immunization program vaccination against rotavirus infection to reduce morbidity and mortality. Excretion of rotavirus vaccine has been reported in fecal samples of vaccinated and unvaccinated children with asymptomatic and symptomatic infections. However, there is paucity of information regarding the circulation of rotavirus and its vaccine strains in Ethiopia. 

Objective: This study was carried out to investigate the presence and circulation of rotavirus vaccine strains.

Method: From November 2015 to April 2016, a total of 450 fecal samples were collected from under-5 children with diarrhea in Gondar and Bahir Dar for detection and genotyping of enteric virus. Basic demographic data were assessed. All stool samples were screened for rotarix vaccine using real-time PCR and sequencing for molecular typing. Phylogenetic analysis and online genotyping tools were used to analyze the sequences.  

Result: During rotavirus surveillance study at outpatient health institution in Northwest Ethiopia, live-attenuated Rotarix vaccine virus was detected in 12/450 (2.7%) of diarrheic children below five years of age. The vaccine virus copies detected in the patients reached up to x10⁹ genome equivalents per gram of stool. Concurrent infections with norovirus, adenovirus, or human parechovirus were frequent.

Conclusion: This finding highlights the need of surveillance of vaccine derived rotavirus infection in children.