Rotavirus

View 'Changing molecular epidemiology of rotavirus infection after introduction of monovalent rotavirus vaccination in Scotland' on the National Centre for Biotechnology Information (NCBI) website.

This laboratory based surveillance study shows significant reduction in reported rotavirus cases and a shift in proportion from G1P[8] to G2P[4] strains after introduction of rotavirus vaccination in Scotland. The data will be used to ascertain cross protection against strains and identify vaccine induced rotavirus strain shifts in the future.

Rotavirus is highly infectious and a leading cause of gastroenteritis in children worldwide. In Scotland, most children will have had at least one rotavirus infection by five years old. Prior to the implementation of the rotavirus vaccination programme, rotavirus reports peaked between February and April. This caused considerable additional pressure on the NHS, particularly in primary care and paediatric healthcare facilities.

In July 2013, Rotarix®, a live attenuated vaccine was introduced into the routine infant vaccination schedule in the UK, with doses given at eight and 12 weeks.

Figure 1 shows the number of rotavirus laboratory reports in Scotland until the end of 2018. Following the introduction of the immunisation programme there has been a marked reduction in numbers of laboratory reports and absence of the seasonal peak, which clearly demonstrates the impact of the vaccine. A reduction of laboratory confirmed rotavirus samples has also been seen in unvaccinated children suggestive of indirect herd protection due to the vaccine.

Figure 2 shows the number of rotavirus laboratory reports in Scotland by week as a five year pre-immunisation average (2009 to 2013) compared to a three year post-immunisation average (2014 to 2016), 2017 and 2018.  The figure shows that the reduction in rotavirus laboratory reports is sustained. Additionally, a further decrease of laboratory reports in 2017 and 2018 compared to the three year post-vaccine average shows the impact of the vaccine has increased as more children are immunised.

Scottish Morbidity Record 01 (SMR01) is a national dataset held by the NHS Information Services Division (ISD) and provides data on admissions to General Acute Inpatient and Day Case.

Surveillance of hospital admissions attributable to rotavirus is undertaken using defined International Classification of Disease 10 (ICD-10) codes for rotavirus and viral enteritis (possible rotavirus).

Figure 3 shows the number of admissions for rotavirus for children aged less than five years by month in the three year period 2014 to 2017 compared to an average of the years 2010 to 2013. This figure shows the impact of the vaccine on rotavirus related hospital admissions of young children. The increase in hospital admissions observed in November and December of 2016, was prior to the rotavirus season and therefore most likely associated with increased circulation of norovirus at that time.

Infections resulting in hospitalisation represent a fraction of cases that occur in the community which, while less severe, cause substantial morbidity. Methods to monitor the impact of the vaccine programme in community settings have also been established to obtain a more complete representation of the impact of the vaccine on the burden of disease.

Figure 4 presents the consultation rate per 100,000 of the population for infants less than one year of age for gastrointestinal illness and compares 2014 to 2018 to an average of 2010 to 2013 before the vaccine was introduced. The impact of the vaccine is clear with an absence of a seasonal peak of consultations corresponding to the rotavirus season in the years 2014 to 2018.