Volume 2 No 29; 18 July 2008
The HPA has published its third annual report on healthcare associated infections (HCAIs) . The aims of this report are to identify key information on HCAI in England, demonstrating the burden of infection when possible, trends, notable events, impact of activities and gaps that need attention. The report focuses on those infections which are subject to mandatory surveillance, but placing them in the context of broader surveillance of bloodstream infections and surgical site infection. This year, the report has been expanded to include contributions on activities in the surveillance, prevention and control of HCAI from across the HPA.
The report reviews the main pathogens causing bloodstream infections, though not all such infections are healthcare-associated. The commonest cause of bloodstream infections continues to be E. coli , which accounts for 18% of all reported bloodstream infections. This proportion has remained stable over the past 5 years. Bloodstream infections due to S. aureus continue to fall; in particular, the downward trend in MRSA infections makes it likely that the national target of a 50% reduction in numbers on the 2003/4 figures will be met. However, bloodstream infections due to coagulase-negative staphylococci are rising, but it is as yet unclear how much of this reflects true infections in vulnerable groups of patients rather than contamination by skin organisms. During the period 2003 to 2007 numbers of reported bloodstream infections associated with Candida species have risen by 37%, whilst those associated with Streptococcus pneumoniae bloodstream infections have reduced by 13%.
Noroviruses are the most commonly detected cause of infectious gastroenteritis and this year's season started uncharacteristically early and peaked early in 2008 with the highest number of reports ever received in a week. Although infections are usually self-limiting and not serious, they can have a major impact in hospitals and the community. The first fall in C. difficile infections in regions and different types of Trusts has been seen, hopefully heralding a downward trend in these infections. The changing pattern in C. difficile ribotypes across the regions of the UK is also of interest, with 027 becoming the predominant type across the country.
There have been notable reductions in surgical site infection rates, particularly in hip and knee replacement surgery and hip arthroplasty. English rates of surgical site infection are comparable with those in other European countries. Two thirds of these infections are superficial.
A new chapter in the report discusses key issues for the future, highlighting areas requiring more attention and how the focus of activity can be extended to reflect the broader public health impact of HCAI.
1. HPA. Surveillance of Healthcare Associated Infections Report 2008. London : Health Protection Agency, 2007. Available at http://www.hpa.org.uk/publications/PublicationDisplay.asp?PublicationID=107
Incidence of STIs among young people is the subject of a new HPA report Sexually transmitted infections and young people in the UK: 2008 report , which highlights the extent to which new cases - particularly chlamydia, gonorrhoea and genital warts - occur among 16-24 year-olds.
The report summarises data on STIs diagnosed at GUM clinics and information collected by the National Chlamydia Screening Programme during the previous year (2007). Latest data show that, whereas only one in eight of the population fall into the 16-24 year-old group, this group accounts for around half of all newly diagnosed STIs in GUM clinics across the UK: 65% of all new chlamydia cases (79,557 of 121,986), 55% of all new genital warts cases (49,250 of 89,838) and 50% of new gonorrhoea diagnoses (9,410 of 18,710).
The report also makes recommendations regarding improvements in services for young people as well as key messages to be imparted to young people so that they can protect themselves from acquiring an STI.
Further infromation regarding annual data on STI diagnoses at GUM clinics during 2007 was published on the HPA website this week. These data are summarised in the Infection Reports section of this issue .
1. Sexually transmitted infections and young people in the UK: 2008 report, http://www.hpa.org.uk/web/HPAwebFile/HPAweb_C/1215589015362
2. Data from UK GUM clinics up to 2007 indicates continued increase in most sexually transmitted infection reports. Health Protection Report, Vol. 2 No. 29, Infection Reports.
An estimated 250,000 individuals were put at risk by the exceedance in cryptosporidial oocysts found in the water supply leaving Pitsford Reservoir during the period 19 to 24 June 2008 . This affected Northampton Town, Daventry, South Northamptonshire and areas in Wellingborough. The exceedence in cryptosporidial oocysts was identified through routine sampling carried out by Anglian Water at this site and a Boiled Water Notice was issued at 6.00 am on the 25 June 2008 after discussions with the East Midlands South Health Protection Unit (HPU). Subsequently, a succession of Incident Control Team meetings took place involving the local HPU, senior Health Protection Agency experts, the Cryptosporidium Reference Laboratory and various local partners. The HPU put out advice to local GPs, A&E Departments and Walk-In Centres and encouraged these colleagues to test people with diarrhoea.
An extensive cleaning and monitoring programme was undertaken throughout the distribution system by Anglian Water and the water leaving Pitsford Reservoir was found to be free of oocysts by 26 June 2008. Considering all the evidence available, the local Incident Control Team - which included representatives from the HPA, Anglian Water, the local Primary Care Trust, local authorities, microbiologists and HPA national experts - decided to lift the Boil Water Notice on Friday 4 July.
The source of the contamination was subsequently identified as a small rabbit that had gained access to the treatment process. Further testing of the water samples taken from the distribution system, and also from the rabbit, carried out by the Cryptosporidium Reference Laboratory in Swansea, confirming that they were of the same strain, identified as a rabbit genotype.
The local HPU has so far been notified of 29 cases of cryptosporidiosis from people in the affected area. Early epidemiological data suggest that most of this disease was a result of exposure to cryptosporidial oocysts before the Boil Water Notice was put in place. Three cases fell outside of this time-frame, taking account of the 3-10 incubation period that was applied.
Detailed genetic analysis carried out at the Cryptosporidium Reference Laboratory showed that 13 of the cases had the rabbit genotype that was found in the water supply. One case had a completely different type and the remaining 15 are still being processed within the laboratory.
The Health Protection Unit is continuing to carry out surveillance and is monitoring for further cases with the help of microbiology laboratories at Northampton General Hospital and Kettering General Hospital and Environmental Health Officers.
Figure 1 shows all confirmed cryptosporidia cases reported to East Midlands South HPU, up to 9 July, by typing result and date of onset. The HPU is carrying out follow-up of all cases and at the present time is awaiting further details of onset dates for three of the cases.
Figure 1. Epidemic curve of cryptosporidiosis by onset date and by typing
Of all 29 cases that have been reported as cryptosporidia there have been 18 cases in females and 11 cases in males. The age distribution of all cases is figure 2.
Figure 2. Age range of all cryptosporidiosis cases by typing results
1. HPA. Large summer and autumn peak of cryptosporidiosis in England and Wales 2003, Health Protection Report [serial online] 2008, 2(26): news. Available at http://www.hpa.org.uk/hpr/archives/2008/hpr2608.pdf
On 10 July 2008, the World Health Organization was notified of a case of Marburg haemorrhagic fever in a Dutch traveller who had recently returned from a holiday in Uganda .
The case was a 40 year-old woman who had travelled to south west Uganda between 5 and 28 June and as part of a tour group, had visited two caves near the Queen Elisabeth National Park (NP). The first cave was visited on 16 June at Fort Portal . No bats were seen in this cave. The second cave (called Python Cave), in the Maramagambo Forest between Queen Elisabeth NP and Kabale, was visited on 19 June where she sustained direct contact with a bat. Only the case, her partner and the guide from the tour party entered the cave. A map showing the location of the cave is available on the European Centre for Disease Prevention and Control website . The case started to show symptoms of fever and chills on 2 July after return to the Netherlands; she was not symptomatic on the flight home. She rapidly deteriorated on 7 July with severe haemorrhaging and died from her illness on 11 July 2008. All those who had close contact with the woman, since she was symptomatic, have been notified and are being monitored. No other members of the tour party have shown similar symptoms.
Python cave is known to harbour species of bat that have been found to carry filoviruses in other parts of sub-Saharan Africa. The Python Cave is being implicated as the likely site of exposure but further epidemiological investigations are ongoing to exclude other possible exposure sites. The WHO has informed the Ministry of Health (MoH) in Uganda who are taking steps to investigate these events; WHO has also recommended that the MoH warn residents and travellers to Uganda against entering caves with bat populations. A small outbreak of Marburg haemorrhagic fever was reported in a mining town in eastern Uganda in late June 2007; bats inside the mine were suspected to be the source of infection .
In the UK, the Federation of Tour Operators has been informed and the National Travel Health Network and Centre have advised that travellers to Uganda should be aware of the apparent risk of contracting Marburg when visiting caves in the Maramagombo forest. Travellers are also advised to avoid other caves in Uganda where bats are present .
Marburg virus is highly transmissible by direct contact with blood, secretions, organs, or other bodily fluids of dead or living infected persons. Transmission can also occur by contact with infected animals (certain species of monkeys and bats). Marburg and Ebola viruses are the causes of the most severe forms of viral haemorrhagic fever (VHF). No cases of Marburg haemorrhagic fever have been reported in the UK to date.
Travellers who have been potentially exposed to Marburg virus should seek medical attention immediately if they experience any of the following symptoms: fever, headache, fatigue, dizziness, muscle aches and weakness within 21 days of the exposure.
More information about VHF (including the Management and Control of Viral Haemorrhagic Fevers Guidance from the Advisory Committee on Dangerous Pathogens, 1996) is available on the HPA website under Marburg Haemorrhagic Fever Background Information, http://www.hpa.org.uk/webw/HPAweb&Page&HPAwebAutoListName/Page/1216193825381?p=1216193825381
1. World Health Organization. Case of Marburg Haemorrhagic Fever imported into the Netherlands from Uganda. Disease Outbreak News, 10 July 2008. [Accessed 16 July 2008.] Available at http://www.who.int/csr/don/2008_07_10/en/index.html.
2. European Centre for Disease Prevention and Control. Imported Marburg case reported in The Netherlands, updated 11 July 2008. [Accessed 16 July 2008.] Available at http://ecdc.europa.eu/.
3. World Health Organization. Managing Marburg fever in Uganda . 10 September 2007. [Accessed 16 July 2008]. Available at http://www.who.int/features/2007/marburg_fever/en/index.html.
4. National Travel Health Network and Centre. Marburg haemorrhagic fever in a traveller to Uganda. Clinical update. 11 July 2008. [Accessed 16 July 2008.] Available at http://www.nathnac.org/pro/clinical_updates/marburg_110708.htm.