Research and analysis

HPR volume 11 issue 11: news (17 March)

Updated 15 December 2017

1. Mandatory HCAI reports quarterly trends: October to December 2016

PHE’s latest quarterly epidemiological commentary on trends in reports of Staphylococcus aureus (MRSA and MSSA) and Escherichia coli bacteraemia, and of Clostridium difficile infections, mandatorily reported by NHS acute Trusts in England up to end-December 2016, has been published on the GOV.UK website [1].

The report includes tabular and graphical presentation of data for the October-December quarter and updates the previous report published in December 2016. Some key facts are listed below.

1.1 MRSA bacteraemia

There was a a steep decline in the rates of all reported and trust-apportioned cases between April-June 2007 (April-June 2008 for trust-apportioned cases) and January-March 2013 – 85% (10.2 to 1.7 cases per 100,000 population) and 78% (4.9 to 1.1 cases per 100,000 bed-days) respectively. This was followed by a further 15% and 21% decrease in the rates of all reported (1.7 to 1.4 cases per 100,000 population) and trust-apportioned cases (1.1 to 0.9 cases per 100,000 bed-days) respectively between that time and the most recent quarter (January-March 2013 to October-December 2016). The decrease in rates of all reported cases was also observed when comparing most recent quarter and the same quarter in the previous financial year (October-December 2015 to October-December 2016) – from 1.5 to 1.4 cases per 100,000 population.

The PIR process for all MRSA bacteraemia cases began in April 2013. Between that time and January-March 2014 (financial year 2013/14), the rates of trust-assigned case remained stable at 1.2 cases per 100,000 bed-days while rates of CCG-assigned cases decreased by 22% from 1.0 to 0.8 cases per 100,000 population. Subsequently after the introduction of third-party assignment category in April 2014, counts and rates of CCG assigned cases decreased from 91 to 77 cases and 0.7 to 0.6 cases per 100,000 population respectively between April-June 2014 and the most recent quarter (October-December 2016). Over the same period, counts and rates of trust-assigned cases increased from 73 to 79 cases and 0.8 to 0.9 cases per 100,000 bed-days respectively. Similarly within the same period, counts and rates of third-party assigned cases increased from 17 to 41 cases and 0.1 to 0.3 cases per 100,000 population respectively.

When comparing the most recent quarter with the same quarter in the previous financial year (October-December 2015 to October-December 2016), rates of trust and CCG-assigned cases increased from 0.8 to 0.9 cases per 100,000 bed-days and 0.5 to 0.6 cases per 100,000 population respectively while rates of third party-assigned cases decreased from 0.5 to 0.3 cases per 100,000 population.

1.2 MSSA bacteraemia

There has been a general trend of increasing counts (31%; from 2,199 to 2,879 cases) and rates (24%; from 16.9 to 20.9 cases per 100,000 population) of all reported MSSA bacteraemia respectively since the mandatory reporting of MSSA bacteraemia began in January-March 2011. Rates of all reported cases from earlier quarters between January-March 2011 and October-December 2013 were relatively stable, fluctuating between 16-17 cases per 100,000 population.

However, in subsequent quarters between October-December 2013 and the most recent quarter (October-December 2016) the rates of all reported MSSA bacteraemia increased each quarter when compared to the same quarter from the previous financial year. The largest increase in rates of all reported MSSA bacteraemia occurring over this period (October-December 2013 to October-December 2016) with a 28% from 16.8 to 20.9 cases per 100,000 population. However, counts and rates of trust-apportioned MSSA bacteraemia increased at a much slower rate compared to that of all reported cases over the same period. While the number of all reported MSSA bacteraemia increased throughout the surveillance period of MSSA (January-March to October-December 2016), the percentage of these cases that were trust-apportioned decreased from 33% to 27% over the same period, indicating that overtime there has been greater increase in community onset cases compared to those that are trust-apportioned (and hospital onset cases).

These overall increases were also observed when comparing the most recent quarters. Between October-December 2015 and October-December 2016, there was an 8% increase in both counts and rates of all reported MSSA bacteraemia (2,672-2,879 cases; 19.4-20.9 cases per 100,000 population respectively). Similarly over the same period there was a 2% increase in both counts and rates of trust-apportioned cases (755-770 cases; 8.7-8.9 cases per 100,000 bed-days respectively).

1.3 E. coli bacteraemia

The counts and rates of all reported E. coli bacteraemia has increased steadily since the initiation of mandatory surveillance of E. coli bacteraemia in July 2011. Count and rates of all reported E. coli bacteraemia increased by 21% (8,275 to 10,042 cases) and 18% (61.7 to 72.9 cases per 100,000 population) respectively between July-September 2011 and October-December 2016, with seasonal peaks generally reported between July and September each year. While these seasonal fluctuations are present – beginning from April-June 2013, each quarter of each year has been higher than the same quarter in the preceding year, implying an overall increase over the time period.

This overall increase has also been observed in the most recent quarters. Between October-December 2015 and October-December 2016, there was a 5% increase in both counts (9,551to 10,042 cases) and rates (69.2 to 72.9 cases per 100,000 population) of all reported cases. The highest rate of all reported cases since the beginning of the mandatory reporting of E. coli bacteraemia was also reported within this period: 78.9 cases per 100,000 populations in July-September 2016.

1.4 C. difficile infection (CDI)

Since the initiation of CDI surveillance in April 2007, there has been an overall decrease in the counts and rates of all reported and trust-apportioned cases of C. difficile infections (CDI) with seasonal peaks in July-September quarter of each year particularly among trust-apportioned cases. The bulk of this decrease occurred between April-June 2007 and January-March 2012 with a 78% and 79% reduction in both counts and rates (16,864 to 3,711 cases and 131.5 to 28.0 cases per 100,000 population respectively), subsequently followed by a 15% and 18% reduction (3,711 to 3,155 and 28.0 and 22.9 cases per 100,000 population respectively) between January-March 2012 and the most recent quarter (October-December 2016).

A similar trend was observed in trust-apportioned CDI with greater decreases in counts and rates over the same period compared to all reported cases. Counts and rates of trust-apportioned CDI decreased by an initial 85% (10,436 to 1,613 cases) and 84% (112.5 to 18.2 cases per 100,000 bed-days) respectively between April-2007 and January-March 2012, followed by a further 27% (1,163 to 1,179 cases) and 25% (18.2 to 13.7 cases per 100,000 bed-days) respectively between January-March 2012 and the most recent quarter.

These decreases are also observed when comparing the most recent quarters – October-December 2015 and October-December 2016. Counts and rates of all reported CDI both decreased by 11% (3,535 to 3,155 cases and 25.6 to 22.9 cases per 100,000 population respectively) while counts and rates of trust-apportioned CDI cases both decreased by 10% (1,307 to 1,179 cases and 15.1 to 13.7 cases per 100,000 bed-days respectively) over the same time period.

1.5 Reference

1. PHE (9 March 2016). Quarterly Epidemiological Commentary: Mandatory MRSA, MSSA and E. coli bacteraemia, and C. difficile infection data (up to October-December 2016).

2. PHE National Immunisation Network Meeting, London, 25-26 April

The science underpinning the maternal, childhood, adolescent and adult immunisation programmes that comprise the national programme in the UK are the subject of the first day of this two-day event. The second day is designed for those with roles in local commissioning, delivery and quality assurance of immunisation programmes.

Venue: Grand Connaught Rooms, London WC2B 5DA. Full programme and on-line registration: National Immunisation Network Meeting.

3. Practical aspects of infection control, Sheffield, 19-20 June

Sheffield Teaching Hospitals, in association with the Healthcare Infection Society, are organising their annual “Don’t Panic!” meeting – for microbiologists and infection control nurses, public health staff and biomedical scientists – on 19 and 20 June 2017.

Venue: The Workstation, central Sheffield. Accommodation is available in local hotels at discounted rates. Poster abstracts submission deadline: 30 April.
Further information and on-line registration: Practical aspects of infection control (Google Chrome or Firefox recommended). Also from: Louise Vella: tel: 0114 305 2741; e-mail: [email protected].