Mukaratirwa A, Berejena C, Nziramasanga P, Ticklay I, Gonah A, Nathoo K, Manangazira P, Mangwanya D, Marembo J, Mwenda JM, Weldegebriel G, Seheri M, Tate JE, Yen C, Parashar U, Mujuru H. Distribution of rotavirus genotypes associated with acute diarrhoea in Zimbabwean children less than five years old before and after rotavirus vaccine introduction.
Vaccine 2018;
36:7248-7255. [PMID:
29628149 DOI:
10.1016/j.vaccine.2018.03.069]
[Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 03/21/2018] [Accepted: 03/26/2018] [Indexed: 10/17/2022]
Abstract
BACKGROUND
Sentinel surveillance for diarrhoea is important to monitor changes in rotavirus epidemiological trends and circulating genotypes among children under 5 years before and after vaccine introduction. The Zimbabwe Ministry of Health and Child Care introduced rotavirus vaccine in national immunization program in May 2014.
METHODS
Active hospital-based surveillance for diarrhoea was conducted at 3 sentinel sites from 2008 to 2016. Children aged less than 5 years, who presented with acute gastroenteritis as a primary illness and who were admitted to a hospital ward or treated at the emergency unit, were enrolled and had a stool specimen collected and tested for rotavirus by enzyme immunoassay (EIA). Genotyping of positive stools was performed using reverse-transcription polymerase chain reaction and genotyping assays. Pre-vaccine introduction, 10% of all positive stool specimens were genotyped and all adequate positive stools were genotyped post-vaccine introduction.
RESULTS
During the pre-vaccine period, a total of 6491 acute gastroenteritis stools were collected, of which 3016 (46%) tested positive for rotavirus and 312 (10%) of the rotavirus positive stools were genotyped. During the post-vaccine period, a total of 3750 acute gastroenteritis stools were collected, of which 937 (25%) tested positive for rotavirus and 784 (84%) were genotyped. During the pre-vaccine introduction the most frequent genotype was G9P[8] (21%) followed by G2P[4] (12%), G1P[8] (6%), G2P[6] (5%), G12P[6] (4%), G9P[6] (3%) and G8P[4] (3%). G1P[8] (30%) was most dominant two years after vaccine introduction followed by G9P[6] (20%), G2P[4] (15%), G9P[8] (11%) and G1P[6] (4%).
CONCLUSION
The decline in positivity rate is an indication of early vaccine impact. Diversity of circulating strains underscores the importance of continued monitoring and strain surveillance after vaccine introduction.
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