Research and analysis

HPR volume 13 issue 25: news (19 and 22 July)

Updated 20 December 2019

EVD outbreak in eastern DRC: PHEIC announced

Following the detection of a confirmed case of Ebola in the city of Goma [1], a meeting of the responsible WHO IHR Emergency Committee was convened on 17 July 2019. This was the fourth meeting of the committee since the outbreak was declared on 1 August 2018 and - on this occasion - it declared that the Ebola outbreak in DRC is a Public Health Emergency of International Concern (PHEIC) [2].

The Emergency Committee noted that effective response to the emergency in DRC remains compromised by factors including insecurity, community acceptance, delays in case detection and isolation, and nosocomial transmission – all of which continue to amplify transmission in affected communities.

Although the intensity of virus transmission has been reduced, seeding of the virus into new areas represents a constant risk of further amplification.

The emergency committee emphasised that the “declaration of the PHEIC is not a reflection on the performance of the response team, but rather a measure that recognizes the possible increased national and regional risks, and the need for intensified and coordinated action to manage them”.

The declaration of a PHEIC reflects the challenges of containing the outbreak in the DRC, and the need for greater international support. It does not change the assessment of risk for the UK population.

PHE is monitoring the situation very closely, but the triggers that would increase the risk to the UK population remain unchanged, and the risk continues to be negligible to very low.

References

1. DRC Ministry of Health update, 14 July 2019 (in French).
2. WHO (17 July 2019). Full statement on the meeting of the Emergency Committee for Ebola virus disease in the DRC.

Transfusion transmitted infections (UK): 2018

Transfusion transmitted infections remain rare in the UK, due to donor selection criteria and rigorous testing of blood donations. National surveillance of Transfusion Transmitted Infections (TTIs) began in 1996, with the national TTI database being hosted at Public Health England (PHE).

Blood centres in England, Wales and Northern Ireland report investigations of suspected TTIs to the joint NHS Blood and Transplant (NHSBT) and PHE Epidemiology Unit.

Each report contains information on:

• the recipient
• the recipient’s infection
• the implicated transfusion
• findings of the investigation

Blood centres in Scotland report all incidents to the Microbiology Reference Unit of the Scottish National Blood Transfusion Service (SNBTS), and the details and conclusion of each case are passed to the surveillance system annually.

During 2018, the UK Blood Services investigated 97 suspected bacterial cases and 8 suspected viral incidents.

From these suspected cases, there have been:

• one confirmed transfusion-transmitted hepatitis E virus (HEV) incident reported by NHSBT
• one probable transfusion-transmitted Staphylococcus epidermidis incident reported by NHSBT
• one probable transfusion-transmitted hepatitis B virus (HBV) incident reported by NHSBT
• one late detection of Staphylococcus aureus incident reported by NHSBT (no evidence of a TTI)

There were no near-miss incidents reported in 2018.

More detailed information on these cases is available from the Serious Hazards of Transfusion (SHOT) Annual Report, Chapter 20 [1].

Key messages from the report are that:

• the risk of a screened component transmitting hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis E virus (HEV) or human immunodeficiency virus (HIV) in the UK is estimated to be extremely low [2]
• to maintain haemovigilance, investigations are performed if a recipient is suspected of having been infected through a transfusion
• bacterial screening of platelets will significantly reduce - but not remove - the risk of transfusion transmission of bacteria

In 2018, there was one confirmed transfusion-transmitted HEV, one probable transfusion-transmitted Staphylococcus epidermidis, and one probable transfusion-transmitted HBV.

In the same year, there was one incident of late detection of Staphylococcus aureus with one recipient receiving an infected donation - but there was no evidence of this leading to a TTI.

Further information about UK TTI surveillance is available from the joint NHS Blood and Transplant (NHSBT) and PHE Epidemiology Unit: epidemiology@nhsbt.nhs.uk.

References

1. Narayan S (ed), Poles D, et al (on behalf of the Serious Hazards of Transfusion (SHOT) Steering Group). The 2018 Annual SHOT Report.
2. Joint United Kingdom (UK) Blood Transfusion and Tissue Transplantation Services Professional Advisory Committee (JPAC): position statements.

Gram-negative bacteraemia, MRSA bacteraemia, MSSA bacteraemia and C. difficile infections, up to and including financial year April 2018 to March 2019

Public Health England’s (PHE) latest annual data and annual epidemiological commentary on trends in reports of healthcare-associated infections (HCAI) in England, up to the financial year 2018 to 2019, has been published on GOV.UK [1,2].

The report features data on Gram-negative bacteraemia (Escherichia coli, Klebsiella species and Pseudomonas aeruginosa), Staphylococcus aureus (MRSA and MSSA) bacteraemia and Clostridioides difficile infections (CDI), mandatorily reported by NHS acute trusts in England.

The report, including tabular and graphical information, provides data for the 2018 to 2019 financial year to update the previous annual report published on 12 July 2018. This is the first time annual data have been presented, on prior trust exposure in CDI.

Some key facts are listed below.

Overview

Overall rates of MRSA bacteraemia and CDI have continued to see year-on-year reductions. These declines in MRSA bacteraemia and CDI rate were in both the community and hospital settings, testament to the success of the interventions introduced to combat these infections.

In contrast, the E. coli and MSSA bacteraemia rates have increased, with the most prominent rises seen in the community-onset cases. MSSA showed a small increase in hospital-onset cases but for E. coli this has been relatively static.

This highlights the need to increase efforts to prevent cases in the community. Nevertheless, hospital-onset infections remain important, representing thousands of cases a year.

The highest rates across all the pathogens were observed among those aged 85 years and older, especially in males. However, a substantial number of cases were observed in the younger age groups. Therefore, prevention strategies should be focused across all patient ages groups if preventable infections are to be minimised, and significant reduction in cases achieved.

Gram-negative bacteraemia

A total of 43,242 cases of E. coli bacteraemia were reported by NHS trusts in England between 1 April 2018 and 31 March 2019. Of the 43,242 E. coli cases, 7,632 (17.6%) were hospital-onset. The total number of cases reported in 2018 to 2019 rose by 5.2% comopared with 2017 to 2018 (total recorded cases: 41,091), and by 33.8% compared with 2012 to 2013 (total recorded cases: 32,309).

The rate of E. coli cases per 100,000 population rose from 60.4 in 2012 to 2013 to 77.7 in 2018 to 2019. The increase in E. coli bactaermias is driven by the community-onset cases, where rates increased from 60.1 in 2017 to 2018 to 64.0 per 100,000 population in 2018 to 2019.

For bacteraemia caused by Klebsiella spp., 10,638 cases were reported by NHS Trusts in England between 1 April 2018 and 31 March 2019. Of the 10,638 Klebsiella spp. cases, 3,182 (29.9%) were hospital-onset.

Fewer cases of bacteraemia were caused by P. aeruginosa than by E. coli or Klebsiella spp. (4,185 cases, of which 36.0% were hospital-onset). This is a reduction in P. aeruginosa bacteraemias from 4.7 in 2017 to 2018 to 4.4 in 2018 to 2019.

Data on the source of bacteraemia indicate that urinary tract infections (UTI) are the predominant source, causing 49.1% of E. coli, 33.5% of Klebsiella spp. and 30% of P. aeruginosa bacteraemias.

MRSA and MSSA bacteraemia

A total of 805 cases of MRSA bacteraemia were reported by NHS acute trusts in England between 1 April 2018 and 31 March 2019.

This is a decrease of 5.2% from 2017 to 2018 (total recorded cases: 849), and a decrease of 81.9% from 2007 to 2008 (total recorded cases: 4,451). The rate of all MRSA cases per 100,000 population, per year, has fallen from 8.6 in 2007 to 2008 to 1.4 in 2018 to 2019. The hospital-onset rate remains low and stable at 0.8 per 100,000 bed-days since 2017 to 2018.

A total of 12,073 cases of MSSA bacteraemia were reported by NHS acute trusts in England between 1 April 2018 and 31 March 2019. This is broadly similar to that of 2017 to 2018 (total recorded cases: 11,948), and an increase of 37.7% from 2011 to 2012 (total recorded cases: 8,767). The rate of all MSSA cases per 100,000 population, per year, has risen from 16.4 in 2011 to 2012 to 21.7 in 2018 to 2019, as have hospital-onset rates from 9.1 in 2017/18 to 9.6 per 100,000 bed-days in 2018 to 2019.

Although a slight decrease was observed in the community-onset rate – from 15.8 per 100,000 population in 2017 to 2018 to 15.7 in 2018 to 2019 – the community-onset component represents 72.5% of all MSSA bacteraemias.

Clostridioides difficile infection

A total of 12,275 cases of Clostridioides difficile infection were reported by NHS trusts in England between 1 April 2018 and 31 March 2019. This is a small decrease of 7.7% from 2017 to 2018 (total recorded cases: 13,299) and a decrease of 77.9% from 2007 to 2008 (total recorded cases: 55,498). The rate of all CDI cases per 100,000 population, per year has fallen from 107.6 in 2007 to 2008 to 22.1 in 2018 to 2019.

[Note: Clostridium difficile taxonomy classification has been changed to Clostridiodes difficile.]

References

1. PHE (11 July 2019). Annual epidemiological commentary: Gram-negative bacteraemia, MRSA bacteraemia, MSSA bacteraemia and C. difficile infections, up to and including financial year April 2018 to March 2019.

2. PHE (11 July 2019). Annual counts and rates of infection by acute trust or CCG and by onset status, England 2018 to 2019: E. coli bacteraemia; Klebsiella spp. bacteraemia; P. aeruginosa bacteraemia; MRSA bacteraemia; MSSA bacteraemia; C. difficile infection.

Infection reports in this issue of HPR

The following infection reports are published in this issue of HPR. The links below are to the relevant webpage collections or publications.

• Laboratory surveillance of candidaemia in England, Wales and Northern Ireland: 2018