• Investigation into the increase in Paecilomyces variotii isolates in the UK from blood culture and other sterile sites
  

• Advice for dentists on single-use of endodontic instruments for all patients to reduce the risk of secondary transmission of vCJD
  

 

 

 

 

 

Investigation into the increase in Paecilomyces variotii isolates in the UK from blood culture and other sterile sites

Following the identification of a possible Paecilomyces variotii contamination problem in October 2006 [1], an investigation was launched by the HPA Centre for Infections (Healthcare Associated Infection and Antimicrobial Resistance Department and Mycology Reference Laboratory [MRL]) in an attempt to identify the source of the increase in sterile site isolates.

Three investigative strands are being followed:

1. a questionnaire survey to laboratories reporting cases requesting information about procedures surrounding venepuncture

2. environmental sampling of blood sampling equipment and clinical sundries, swabbing of surfaces and placement of settle plates

3. analysis of NHS Supply Chain data detailing the supply-line of specific equipment used in venepuncture and other clinical sundries for affected and unaffected acute hospital trusts in UK.

Cases, which are defined as confirmed Paecilomyces sp isolated from a sterile site by a UK laboratory since 1 July 2006 but not considered clinically significant, were identified through isolate referrals and reports to MRL alerts issued to laboratories through the Regional Microbiology Network (England) and in CDR Weekly [1], and to the relevant contact point in Scotland Wales, and Northern Ireland. Information on any similar contamination problems was requested from other national public health institutes via Eurosurveillance [2].

To date, 94 Paecilomyces contaminant isolates from 29 laboratories have been reported, with the majority being isolated between September and November 2006. Numbers of reports have tailed off, with only two being reported in 2007 to date. Most isolates (90) of P. variotii were reported from England, with only four from elsewhere in the United Kingdom and Crown Dependencies. No isolates were reported from Scotland or Wales and there were no reports of Paecilomyces contaminant problems from the rest of Europe.

Preliminary results from questionnaires received from 23 laboratories showed most isolates were from blood cultures (88%), with the rest isolated from other sterile sites. Samples were drawn across most specialties, reflecting the normal distribution of blood cultures. Concurrent contamination was rarely reported. Further analysis of questionnaire data, environmental sampling, and the supply chain is in progress.

To gauge whether the problem is ongoing, we ask any laboratory that prospectively isolates Paecilomyces or has isolated it and not reported this to contact the HPA (details below). If any future Paecilomyces contaminants are isolated, we would also request the assistance of laboratories in retrieving equipment and clinical sundries from the ward where the specimen was drawn and undertaking some environmental sampling from this area and/or from where the equipment was stored. A set of instructions will be emailed to any laboratory willing to assist in this process.

Laboratories that isolate any further Paecilomyces sp are kindly requested to contact Colin Campbell at the Centre for Infections, tel: 020 8327 7146; email: colin.campbell@hpa.org.uk.

References
1. HPA. Suspected cases of Paecilomyces variotii pseudofungaemia. Commun Dis Rep CDR Wkly; [serial online] 2006 [accessed 16 April 2007];16(44)]: news. Available at <http://www.hpa.org.uk/cdr/archives/2006/cdr4406.pdf>.

2. Lamagni T, Campbell C, Pezzoli L, Johnson E. Unexplained increase in Paecilomyces variotii blood culture isolates in the UK. Eurosurveillance [serial online] 2006 [accessed 16 April 2007];11(11):E061116.2. Available from <http://www.eurosurveillance.org/ew/2006/061116.asp#2>.

 

 

 

 

 

 

 

 

 

 

Advice for dentists on single-use of endodontic instruments for all patients to reduce the risk of secondary transmission of vCJD

The Department of Health has received early findings from research in progress by the HPA, at the Centre for Emergency Preparedness and Response. Results from studies in mice have found transmissible spongiform encephalopathy (TSE) infectivity in dental tissues. The research is ongoing and further advice will be sought from the Spongiform Encephalopathy Advisory Committee (SEAC) and other advisory groups. The results support the possibility that dental files and reamers (most commonly used in root canal treatment) could pose an effective route of transmission of variant Creutzfeldt-Jakob disease (vCJD) infection.

The Chief Dental Officer for England (CDO) has written to all dentists practising in primary or secondary care advising them to restrict endodontic reamers and files to single use for all patients. This is on a precautionary basis in order to reduce any risk of vCJD transmission. He has also advised dentists to ensure that the highest standards of decontamination are observed for all dental instruments and that manufacturers’ decontamination instructions are followed [1].

This new guidance from the CDO is an extra precaution resulting from the recent research and the public should be advised to continue to attend their dentist for the treatment that they require.

Advice and guidance from the ACDP TSE Working Group regarding dentistry for individuals with or at-risk of vCJD remain for the present unchanged [2,3].

References

1. Chief Dental Officer for England. Advice for dentists on re-use of endodontic instruments and variant Creutzfeldt-Jakob disease (vCJD). London: Department of Health, 2007. Available at <http://www.dh.gov.uk/en/Publicationsandstatistics/Lettersandcirculars/Dearcolleagueletters/DH_074001>.

2. Transmissible spongiform encephalopathy agents: safe working and the prevention of infection. Guidance from the Advisory Committee on Dangerous Pathogens and the Spongiform Encephalopathy Advisory Committee. Deprtment of Health website [online] 2007 [accessed 19 April 2007]. Available at <http://www.advisorybodies.doh.gov.uk/acdp/tseguidance/index.htm>.

3. Chief Dental Officer for England. Information for dentists about the management of patients with or at risk of, Creutzfeldt-Jakob disease (CJD) including variant CJD (vCJD). London: Department of Health, 2005. Available at <http://www.dh.gov.uk/en/Publicationsandstatistics/Lettersandcirculars/Dearcolleagueletters/DH_4102752>.