Jukka Markkula1, Maria Hemming-Harlo2, Carita Savolainen-Kopra3, Haider Al-Hello4, Timo Vesikari5. 1. Vaccine Research Center, Tampere University, Biokatu 10, 33520 Tampere, Finland. Electronic address: jukka.markkula@tuni.fi. 2. Vaccine Research Center, Tampere University, Biokatu 10, 33520 Tampere, Finland; Department of Pediatrics, Tampere University Hospital, PL 2000, 33521 Tampere, Finland. Electronic address: maria.hemming-harlo@tuni.fi. 3. National Institute for Health and Welfare, PL 30, 00271 Helsinki, Finland. Electronic address: carita.savolainen-kopra@thl.fi. 4. National Institute for Health and Welfare, PL 30, 00271 Helsinki, Finland. Electronic address: haider.al-hello@thl.fi. 5. Vaccine Research Center, Tampere University, Biokatu 10, 33520 Tampere, Finland. Electronic address: timo.vesikari@tuni.fi.
Abstract
OBJECTIVES: To determine occurrence of residual rotavirus (RV) disease in different age groups in Finland after five to nine years of high coverage (≥90%) mass-vaccination with RotaTeqⓇ vaccine, and to examine the vaccine effect on circulating genotypes. METHODS: Since 2013 all clinical laboratories in the country were obliged to send RV positive stool samples for typing. RVs were genotyped by RT-PCR for VP7 and VP4 proteins, sequenced and compared to reference strains. RESULTS: RV continued to circulate throughout the study period at low level with a small increase in 2017-2018. There were three age-related clusters: young children representing primary or secondary vaccine failures, school-age children who may not have been vaccinated, and the elderly. Genotype distribution differed from the pre-vaccination period with a steady decline of G1P[8], emergence of G9P[8] and especially more recently G12P[8]. In the elderly, G2P[4] was predominant but was also replaced by G12P[8] in 2017-18. CONCLUSIONS: RV vaccination with a high coverage keeps RV disease at low level but does not prevent RV circulation. New RV genotypes have emerged replacing largely the previously predominant G1P[8]. Increase of overall RV activity with emergence of G12P[8] in the latest follow-up season 2017-18 might be a potential alarm sign.
OBJECTIVES: To determine occurrence of residual rotavirus (RV) disease in different age groups in Finland after five to nine years of high coverage (≥90%) mass-vaccination with RotaTeqⓇ vaccine, and to examine the vaccine effect on circulating genotypes. METHODS: Since 2013 all clinical laboratories in the country were obliged to send RV positive stool samples for typing. RVs were genotyped by RT-PCR for VP7 and VP4 proteins, sequenced and compared to reference strains. RESULTS: RV continued to circulate throughout the study period at low level with a small increase in 2017-2018. There were three age-related clusters: young children representing primary or secondary vaccine failures, school-age children who may not have been vaccinated, and the elderly. Genotype distribution differed from the pre-vaccination period with a steady decline of G1P[8], emergence of G9P[8] and especially more recently G12P[8]. In the elderly, G2P[4] was predominant but was also replaced by G12P[8] in 2017-18. CONCLUSIONS: RV vaccination with a high coverage keeps RV disease at low level but does not prevent RV circulation. New RV genotypes have emerged replacing largely the previously predominant G1P[8]. Increase of overall RV activity with emergence of G12P[8] in the latest follow-up season 2017-18 might be a potential alarm sign.
Authors: Celeste M Donato; Susie Roczo-Farkas; Carl D Kirkwood; Graeme L Barnes; Julie E Bines Journal: J Infect Dis Date: 2022-06-15 Impact factor: 7.759