- Email: [email protected]
Role of the clinical microbiology laboratory in infection control — a Danish perspective
]oumol of Hospital Infection (200 I) 48 (Supplement A): S5&S54 doi: IO. I053/jhin.200 I .0970, available online at http://www.idealibrary.com
on 1 mE kl”
Role of the clinical microbiology laboratory infection control - a Danish perspective
in
H. j. Kolmos Department of Clinical Microbiology, Odense University Hospital, DK-5000 Odense, Denmark
Summary: Clinical microbiology laboratories in Denmark are located in hospitals and staffed by clinical microbiologists who are clinically trained medical doctors. Each county has its own clinical microbiology unit, serving a population of 0.34.6 million. The responsibilities of clinical microbiology unit cover many different aspects of infection control. They include detection of outbreaks of hospital-acquired infections, screening for multi-resistant organisms, advice to clinicians about disinfection, sterilization and isolation procedures, and the rational use of antibiotics. Clinical microbiologists work closely with infection control nurses. Together they form the infection control team, which is the executive part of the local infection control committee. The infection control team is also the main body responsible for the deveIopment of guidelines, which are approved by the regional infection control committee. The local microbiology laboratories work in close contact with the National Department of Hospital Hygiene and other reference laboratories at the State Serum Institute. The present structure of infection control was established 25 years ago. The main aim at that time was to decentralize infection control and establish facilities as close to clinicians and patients as practically possible. This has solved most basic problems related to infection control, and compliance by clinicians has been fairly good. However, the present organization will not meet future requirements for standardization and documentation of quality. Currently a national standard for infection control is being prepared. It consists of a main standard defining requirements for the management system and 12 subsidiary standards defining requirements for specific areas of infection control. Adoption of the standard will undoubtedly require additional resources for infection control at a local level, and some organizational changes may also be needed. Infection control should be maintained as an integrated part of clinical microbiology. 0 200 I The Hospital
Keywords:
Clinical
microbiology;
clinical
microbiologist;
Introduction The present organization of infection control in Denmark dates from 1975, when responsibility for infection control was decentralized from the nationa board of health to the counties, which run the hospital service in Denmark. Practical issues became the responsibility of clinical microbiologists in
Author for correspondence: Professor Hans Jern Kolmos, Department of Clinical Microbiology, Odense University Hospital, Winslowparken 212, DK-5000 Odense C, Denmark. Fax: +45 65414785; E-mail: [email protected]
0 195-670 I/O IlOAOS50
+ 05 $35.00/O
infection
Infection
Society
control.
existing local laboratories, and infection control committees were established in hospitals. Most counties also established a central committee to co-ordinate infection control in their own area. At a national level, the State Serum Institute established a department of hospital hygiene to provide expert assistance for the local infection control organizations. A formalized education of infection control nurses was established a few years later. Today the local infection control organization typically comprises one or two infection control nurses and a clinical microbiologist employed part-time. Together they form the executive part of the local infection control committees, which also include
0 2001 The Hospital
Infection
Society
Microbiology
laboratory
and infection
s51
control
representatives from clinical units, hospital management, hospital pharmacy, technical departments, sterile supplies, and other relevant paramedical staff.
The clinical
microbiology
laboratory
In Denmark clinical microbiology laboratories are integrated within hospitals. There is, on average, one unit in each county, located within the local university hospital or main county hospital, covering a population of 0.3-0.6 million inhabitants. The microbiology laboratories work in close cooperation with clinical units, and provide a 24-h service with a clinical microbiologist on call outside ordinary working hours.’ They also work in close co-operation with reference laboratories centralized at the State Serum Institute in Copenhagen. In addition to technical personnel, these are staffed by clinical microbiologists trained in laboratory medicine and infection control.’ Clinical microbiology laboratories play an important part in infection control by uncovering problems in samples sent to the laboratory for routine Table I Outbreaks of hospital-acquired infection recognized Hospital and Hvidovre Hospital over the past 25 years*
diagnostic purposes. In past years many different outbreaks of hospital-acquired infection have been detected by the clinical laboratories, and sources of infections have been identified, as illustrated in Table I.2-‘o Important new knowledge has been gathered from these outbreaks, and resulted in measures that were originally implemented locally and then adopted nation-wide. For instance, all Danish hospitals today screen patients transferred from hospitals outside Scandinavia for MRSA and other multi-resistant organisms.‘,4 Clinical alertness in the laboratory is a rapid and efficient means of detecting outbreaks with unusual micro-organisms, or micro-organisms with unusual phenotypical traits, e.g., multiple antibiotic resistance. Detection of outbreaks of common organisms without special phenotypical traits is difficult by clinical alertness alone, and usually relies on periodic summaries electronically stored laboratory data. The main disadvantage of such surveillance programmes is that they are relatively slow in detecting outbreaks. Due to the limited number of specimens received from the single departments, figures for different organisms can
by clinical alertness
in the deportments
of clinical microbiology
at Odense University
Year (reference)
Department
Type of infection
Micro-organism
Source of outbreak
Intervention
1976-77
Nephrology
Peritonitis in peritoneal dialysis patients Bacteraemia
Pseudomonas aeruginosa Pseudomonas cepacia
Water bath used to preheat dialysis fluids Intrinsic contamination of anaesthetic (fentanyl)
Wound infection, pneumonia
MRSA (imported
Patient transferred from hospital abroad
Cardiovascular surgery Infectious diseases
Bacteraemia
Achromobacter xyfosoxidans Cryptosporidium parvum
Re-use of disposable pressure transducers Ice machine
Introduction of dry heat incubators Withdrawal of contaminated batch; autoclave of vials Screening for MRSA of patients transferred from hospitals outside Scandinavia Re-use abandoned
Orthopedic
Surgical wound infection, septicaemia
Streptococcus pyogenes
Surgeon (throat carrier)
Pseudo-outbreak
Pseudomonas aeruginosa
Bronchoscopes
Transfusion related septicaemia
Serratia marcescens
Commercial transfusion
Wound infection, septicaemia
Pseudomonas aeruginosa
Tap water irrigation
(2)
I977 (3)
Hospitals in Denmark and The Netherlands
1979 (4)
Burns unit
1985-87
(5)
I989 (6)
1990-91
(7)
surgery
I99 l(8)
Infectious
1991 (9)
Hospitals in Denmark, Sweden and other European countries ICU + burns unit
1991 (IO)
*Only outbreaks
published
diseases
in international
Gastro-enteritis
journals
have been included.
strain)
blood bags used for of burns
Restriction of access to ice machine and enforcement of hygiene Increased alertness to the possibility of S. pyogenes carriers in the operating theatre Enforcement of mechanical cleansing and introduction of alcohol flush Introduction of blood bags with sterile exterior Heat disinfection of shower heads after use
s52
H. J. Kolmos
hardly be compared more frequently than at halfyear intervals.“,12 It is important that clinical microbiology laboratories communicate any suspicion of outbreaks with each other so that other laboratories can look out for similar cases and thereby contribute to the identification of common sources of infection. Two of the outbreaks listed in Table II were widely distributed and involved several hospitals in Denmark and abroad.3,9 Despite this, they were rapidly controlled because a close network of contacts existed among laboratories and health authorities in Denmark, and with a number of other European countries.
Restriction in hospitals
of antibiotic
consumption
Rational use of antibiotics is essential to infection control in hospitals, and the microbiologist contributes to this in several ways. Frequent contacts with clinicians and an involvement in the treatment of patients is probably the most important way to control antibiotic consumption. However, the microbiologist also contributes by educational programmes, producing written guidelines, and undertaking audit.’ To be effective, education and audit must take place continuously, partly because junior staff members often change positions, and partly because good prescribing habits have a tendency to deteriorate over time. Danish microbiologists have been working very actively with antibiotic policies for over 30 years. As a result Denmark today ranks among the countries in the world with the lowest consumption of antibiotics. If antibiotics are considered necessary, priority is given to penicillins and other presumed ecologically favourable agents in order to minimize the risk of hospital-acquired infections and the development of resistance.’ Presumably in consequence of this restrictive antibiotic policy, Denmark has avoided many of the resistance problems seen elsewhere, and in some respects has been able to improve matters. A striking example of this is MRSA. Since 1960 all blood isolates of Staphylococcus aureus from local clinical microbiology laboratories have been referred to the State Serum Institute for phage typing and surveillance of resistance. In the 1960s MRSAs were quite prevalent; however, from the middle of the 1970s they began to decline, and now account for less than one percent of S. aweus.‘” Another remarkable development is that there is no longer a distinctive hospital bacterial flora. Today
S. aureus isolates from hospitalized patients show the same phage type distribution as communityacquired isolates, and the frequency of antimicrobial resistance characters is the same.” Similar observations have been made with Escherichia coli, Klebsiella, and Enterobacter cloacae.‘5-‘7 This fortunate development, which contrasts with the situation in many other countries may be seen as the result of a restrictive antibiotic policy combined with a relatively good standard of hygiene in hospitals.
Surveillance
programmes
Cumulative results of culture and antimicrobial sensitivity testing, generated by the clinical microbiological laboratory, are an extremely important source of data for infection control surveillance. Periodic summaries of the most important hospital-acquired pathogens, including their antimicrobial susceptibility profiles, should be produced by the clinical microbiological laboratory and made available to the local infection control team. This exercise is greatly facilitated if laboratory test results are stored electronically, and if programmes for extracting relevant data are available. Surveillance of selected hospital-acquired pathogens in the local clinical microbiological laboratory should, if possible, take place in close cooperation with reference laboratories. The clinical microbiological laboratory may send strains to a central reference laboratory, or may transmit locally produced laboratory data to a central database. An example of this is the national S. aureus database maintained at the State Serum Institute, which has received strains and data from local clinical microbiological laboratories for more than 30 years. This database provides invaluable information about staphylococcal epidemiology in Denmark (phage types, antibiotic susceptibility, etc.).13 Several microbiology laboratories contribute to the national surveillance of antimicrobial resistance by reporting data to the Danish Integrated Antimicrobial Resistance Monitoring and Research Programme (DANMAP). This programme integrates data on antimicrobial consumption and antimicrobial resistance in bacteria from humans and food animals.18 National
standards
of infection
control
The recent years’ emphasis on quality assurance and infection control has led to discussions on the adequacy of the present organization. Despite limited
Microbiology
laboratory
and infection
s53
control
resources it has managed to solve most basic problems related to infection control; however, it is unlikely to be ready to face future requirements for standardization and documentation of quality. Therefore a national standard of infection control is being prepared with the overall aim of strengthening infection control, both in hospitals and in primary health care. It consists of two elements: a main standard, which describes the requirements for the management system, and 12 subsidiary standards, which describe the requirements for special areas of infection control. The main standard consists of four process-related elements, defining management responsibility, guidance on resources, guidance on infection control measures, and measurement, analysis and improvement. Together these four elements constitute an audit circle. The 12 subsidiary standards deal with all major areas of infection control. They comprise general practice, hand hygiene, intravenous catheters, surveillance and investigation of outbreaks, surgical site infections, urine continence aids, urinary catheters, textiles, purchase and maintenance of equipment, cleaning and quality control, foodstuffs and dental clinics. The contents of the 12 subsidiary standards are based on existing guidelines; however, the main standard is largely innovative. The main purpose of the latter is to secure compliance with guidelines, which is the weak point of the present organization. It is for the county councils and local hospitals to decide, whether or not they will introduce the standards. Furthermore, they are free to decide, how many of the standards from the package they wish to introduce. The only obligation is that as a minimum they must introduce the standard defining the requirements for the management plus one of the subsidiary standards.
Introducing the standards implies that there should be more focus on management and on identification and correction of errors. In consequence the demands for surveillance and audit will increase substantially. In order to meet this, the local infection control organizations will need more manpower and equipment. In particular there will be a need for more infection control nurses. Furthermore many clinical microbiologists will need to specialize and dedicate all their working time to infection control. This raises the question as to whether infection control should be kept as a part of clinical microbiology, or form an organization of its own. The advantages of a separate organization are that infection control is accorded a higher profile and has greater impact on the management system. However, it is not clear that this will lead to higher quality. The disadvantages are those of a more bureaucratic system with an administrative barrier between the diagnostic laboratory and the infection control organization. If infection control moves from the hands of clinical microbiologists, who include the diagnosis and treatment of infections in their daily work, then there is a risk that the present close contacts with clinicians will be weakened. The consequence of this may be that clinicians become less compliant. Considering the advantages and disadvantages it still seems most appropriate to maintain infection control integrated within clinical microbiology. What is needed is clinical microbiologists, who will specialize and dedicate more time to infection control. This can be achieved within the existing organizing framework by supplementary training, and by providing a more precise job description for microbiologists working within infection control.
References Discussion Infection control in Denmark is run with few resources. There are very few people employed fulltime in infection control. In fact these comprise only the infection control nurses, of whom there are on average two per county. They typically cover up to 2000 hospital beds, in addition to nursing homes and other institutions in primary health care. Despite low budgets, the present organization has managed to solve all basic problems related to infection control. However, it is evident that it is not ready to meet the additional work load caused by new standards.
Kolmos HJ. Interaction between the microbiology laboratory and clinician: what the microbiologist can provide. J Hasp Infect 1999; 43(Suppl): S285-S291. Kolmos HJ, Andersen KEH. Peritonitis with Pseudomonad aeruginosa in hospital patients treated with peritoneal dialysis. Stand 3’ Infect Dis 1979; 11: 207-210.
Siboni K, Olsen H, Ravn E et al. Pseudomonas cepacia in 16 non-fatal cases of postoperative bacteremia derived from intrinsic contamination of the anaesthetic fentanyl. ScandJ Infect Dis 1979; 11: 39-45. Espersen F, Nielsen PB, Lund K, Sylvest B, Jensen K. Hospital-acquired infections in a burn unit caused by an imvorted strain of Staahvlococcus aureus with
554
5.
6.
7.
8.
9.
10.
11.
12.
H. J. Kolmos
unusual multiresistance. J Hyg Camb 1982; 88: 535-541. Gahrn-Hansen B, Alstrup P, Dessau R et al. Outbreak of infection with Achromobacter xylosoxidans from contaminated intravascular pressure transducers. J Hosp Infect 1988; 12: 1-6. Ravn P, Lundgren JD, Kjaeldgaard P et al. Nosocomial outbreak of crytosporidiosis in AIDS patients. BMJ 1991; 302: 277-280. Kolmos HJ, Svendsen RN, Nielsen SV. The Surgical team as a source of postoperative wound infections caused by Streptococcus pyogenes. J Hosp Infect 1997; 35: 207-214. Kolmos HJ, Lerche A, Kristoffersen K, Rosdahl VT. Pseudo-outbreak of Pseudomonas aeruginosa in HIVinfected patients undergoing fiberoptic bronchoscopy. ScandJ Infect Dis 1994; 26: 653-657. Heltberg 0, Skov F, Gerner-Smidt P et al. Nosocomial epidemic of Serrutia marcescens septicemia ascribed to contaminated blood transfusion bags. Transfusion 1993; 33: 221-227. Kolmos HJ, Thuesen B, Nielsen SV, Lohmann M, Kristoffersen K, Rosdahl VT. Outbreak of infection in a burns unit due to Pseudomonas aeruginosa originating from contaminated tubing used for irrigation of patients r Hosp Infect 1993; 24: 11-21. Hansen L, Kolmos HJ, Siboni K. Detection of cumulations of infections over a three-year period using electronic data processing. Dan Med Bull 1978; 25: 253-257. Gerner-Smidt P, Hansen L, Knudsen A, Siboni K, Sogaard I. Epidemic spread of Acinetobacter
13.
14.
15.
16.
17.
18.
calcoaceticus in a neurosurgical department analysed by electronic data processing. J Hosp Infect 1985; 6: 166-174. Espersen F, Rosdahl VT, Frimodt-Meller N, Skinhoj P Epidemiology of Staphylococcus aureus bacteraemia in Denmark. J Chemother 1994; 6: 219-225. Rosdahl VT, Westh H, Jensen K. Antibiotic susceptibility and phage-type pattern of Staphylococcus aureus strains isolated from patients in general practice compared to strains from hospital patients. ScandJ Infect Dis 1990; 22: 315-320. Olesen B, Kolmos HJ, Orskov F, Orskov I. A comparative study of nosocomial and communityacquired strains of Escherichia coli causing bacteraemia in a Danish university hospital. r Hosp Infect 1995; 31: 295-304. Hansen DS, Gottschau A, Kolmos HJ. Epidemiology of Klebsiella bacteraemia: a case control study using E. coli bacteraemia as control. J Hosp Infect 1998; 38: 119-132. Weischer M, Kolmos HJ. Ribotyping of selected isolates of Enterobacter cloacae and clinical data related to biotype, phage type, 0-serotype, and ribotype. APMIS 1993; 101: 879-886. Bager F (ed). DANMAP 99. Consumption of antimicrobial agents and occurrence of antimicrobial resistance in bacteria from food animals, food and humans in Denmark. ISSN 1600-2032 (http://www.svs.dk/dk/Organisation/z/danmap 1999.pdf).
on 1 mE kl”
Role of the clinical microbiology laboratory infection control - a Danish perspective
in
H. j. Kolmos Department of Clinical Microbiology, Odense University Hospital, DK-5000 Odense, Denmark
Summary: Clinical microbiology laboratories in Denmark are located in hospitals and staffed by clinical microbiologists who are clinically trained medical doctors. Each county has its own clinical microbiology unit, serving a population of 0.34.6 million. The responsibilities of clinical microbiology unit cover many different aspects of infection control. They include detection of outbreaks of hospital-acquired infections, screening for multi-resistant organisms, advice to clinicians about disinfection, sterilization and isolation procedures, and the rational use of antibiotics. Clinical microbiologists work closely with infection control nurses. Together they form the infection control team, which is the executive part of the local infection control committee. The infection control team is also the main body responsible for the deveIopment of guidelines, which are approved by the regional infection control committee. The local microbiology laboratories work in close contact with the National Department of Hospital Hygiene and other reference laboratories at the State Serum Institute. The present structure of infection control was established 25 years ago. The main aim at that time was to decentralize infection control and establish facilities as close to clinicians and patients as practically possible. This has solved most basic problems related to infection control, and compliance by clinicians has been fairly good. However, the present organization will not meet future requirements for standardization and documentation of quality. Currently a national standard for infection control is being prepared. It consists of a main standard defining requirements for the management system and 12 subsidiary standards defining requirements for specific areas of infection control. Adoption of the standard will undoubtedly require additional resources for infection control at a local level, and some organizational changes may also be needed. Infection control should be maintained as an integrated part of clinical microbiology. 0 200 I The Hospital
Keywords:
Clinical
microbiology;
clinical
microbiologist;
Introduction The present organization of infection control in Denmark dates from 1975, when responsibility for infection control was decentralized from the nationa board of health to the counties, which run the hospital service in Denmark. Practical issues became the responsibility of clinical microbiologists in
Author for correspondence: Professor Hans Jern Kolmos, Department of Clinical Microbiology, Odense University Hospital, Winslowparken 212, DK-5000 Odense C, Denmark. Fax: +45 65414785; E-mail: [email protected]
0 195-670 I/O IlOAOS50
+ 05 $35.00/O
infection
Infection
Society
control.
existing local laboratories, and infection control committees were established in hospitals. Most counties also established a central committee to co-ordinate infection control in their own area. At a national level, the State Serum Institute established a department of hospital hygiene to provide expert assistance for the local infection control organizations. A formalized education of infection control nurses was established a few years later. Today the local infection control organization typically comprises one or two infection control nurses and a clinical microbiologist employed part-time. Together they form the executive part of the local infection control committees, which also include
0 2001 The Hospital
Infection
Society
Microbiology
laboratory
and infection
s51
control
representatives from clinical units, hospital management, hospital pharmacy, technical departments, sterile supplies, and other relevant paramedical staff.
The clinical
microbiology
laboratory
In Denmark clinical microbiology laboratories are integrated within hospitals. There is, on average, one unit in each county, located within the local university hospital or main county hospital, covering a population of 0.3-0.6 million inhabitants. The microbiology laboratories work in close cooperation with clinical units, and provide a 24-h service with a clinical microbiologist on call outside ordinary working hours.’ They also work in close co-operation with reference laboratories centralized at the State Serum Institute in Copenhagen. In addition to technical personnel, these are staffed by clinical microbiologists trained in laboratory medicine and infection control.’ Clinical microbiology laboratories play an important part in infection control by uncovering problems in samples sent to the laboratory for routine Table I Outbreaks of hospital-acquired infection recognized Hospital and Hvidovre Hospital over the past 25 years*
diagnostic purposes. In past years many different outbreaks of hospital-acquired infection have been detected by the clinical laboratories, and sources of infections have been identified, as illustrated in Table I.2-‘o Important new knowledge has been gathered from these outbreaks, and resulted in measures that were originally implemented locally and then adopted nation-wide. For instance, all Danish hospitals today screen patients transferred from hospitals outside Scandinavia for MRSA and other multi-resistant organisms.‘,4 Clinical alertness in the laboratory is a rapid and efficient means of detecting outbreaks with unusual micro-organisms, or micro-organisms with unusual phenotypical traits, e.g., multiple antibiotic resistance. Detection of outbreaks of common organisms without special phenotypical traits is difficult by clinical alertness alone, and usually relies on periodic summaries electronically stored laboratory data. The main disadvantage of such surveillance programmes is that they are relatively slow in detecting outbreaks. Due to the limited number of specimens received from the single departments, figures for different organisms can
by clinical alertness
in the deportments
of clinical microbiology
at Odense University
Year (reference)
Department
Type of infection
Micro-organism
Source of outbreak
Intervention
1976-77
Nephrology
Peritonitis in peritoneal dialysis patients Bacteraemia
Pseudomonas aeruginosa Pseudomonas cepacia
Water bath used to preheat dialysis fluids Intrinsic contamination of anaesthetic (fentanyl)
Wound infection, pneumonia
MRSA (imported
Patient transferred from hospital abroad
Cardiovascular surgery Infectious diseases
Bacteraemia
Achromobacter xyfosoxidans Cryptosporidium parvum
Re-use of disposable pressure transducers Ice machine
Introduction of dry heat incubators Withdrawal of contaminated batch; autoclave of vials Screening for MRSA of patients transferred from hospitals outside Scandinavia Re-use abandoned
Orthopedic
Surgical wound infection, septicaemia
Streptococcus pyogenes
Surgeon (throat carrier)
Pseudo-outbreak
Pseudomonas aeruginosa
Bronchoscopes
Transfusion related septicaemia
Serratia marcescens
Commercial transfusion
Wound infection, septicaemia
Pseudomonas aeruginosa
Tap water irrigation
(2)
I977 (3)
Hospitals in Denmark and The Netherlands
1979 (4)
Burns unit
1985-87
(5)
I989 (6)
1990-91
(7)
surgery
I99 l(8)
Infectious
1991 (9)
Hospitals in Denmark, Sweden and other European countries ICU + burns unit
1991 (IO)
*Only outbreaks
published
diseases
in international
Gastro-enteritis
journals
have been included.
strain)
blood bags used for of burns
Restriction of access to ice machine and enforcement of hygiene Increased alertness to the possibility of S. pyogenes carriers in the operating theatre Enforcement of mechanical cleansing and introduction of alcohol flush Introduction of blood bags with sterile exterior Heat disinfection of shower heads after use
s52
H. J. Kolmos
hardly be compared more frequently than at halfyear intervals.“,12 It is important that clinical microbiology laboratories communicate any suspicion of outbreaks with each other so that other laboratories can look out for similar cases and thereby contribute to the identification of common sources of infection. Two of the outbreaks listed in Table II were widely distributed and involved several hospitals in Denmark and abroad.3,9 Despite this, they were rapidly controlled because a close network of contacts existed among laboratories and health authorities in Denmark, and with a number of other European countries.
Restriction in hospitals
of antibiotic
consumption
Rational use of antibiotics is essential to infection control in hospitals, and the microbiologist contributes to this in several ways. Frequent contacts with clinicians and an involvement in the treatment of patients is probably the most important way to control antibiotic consumption. However, the microbiologist also contributes by educational programmes, producing written guidelines, and undertaking audit.’ To be effective, education and audit must take place continuously, partly because junior staff members often change positions, and partly because good prescribing habits have a tendency to deteriorate over time. Danish microbiologists have been working very actively with antibiotic policies for over 30 years. As a result Denmark today ranks among the countries in the world with the lowest consumption of antibiotics. If antibiotics are considered necessary, priority is given to penicillins and other presumed ecologically favourable agents in order to minimize the risk of hospital-acquired infections and the development of resistance.’ Presumably in consequence of this restrictive antibiotic policy, Denmark has avoided many of the resistance problems seen elsewhere, and in some respects has been able to improve matters. A striking example of this is MRSA. Since 1960 all blood isolates of Staphylococcus aureus from local clinical microbiology laboratories have been referred to the State Serum Institute for phage typing and surveillance of resistance. In the 1960s MRSAs were quite prevalent; however, from the middle of the 1970s they began to decline, and now account for less than one percent of S. aweus.‘” Another remarkable development is that there is no longer a distinctive hospital bacterial flora. Today
S. aureus isolates from hospitalized patients show the same phage type distribution as communityacquired isolates, and the frequency of antimicrobial resistance characters is the same.” Similar observations have been made with Escherichia coli, Klebsiella, and Enterobacter cloacae.‘5-‘7 This fortunate development, which contrasts with the situation in many other countries may be seen as the result of a restrictive antibiotic policy combined with a relatively good standard of hygiene in hospitals.
Surveillance
programmes
Cumulative results of culture and antimicrobial sensitivity testing, generated by the clinical microbiological laboratory, are an extremely important source of data for infection control surveillance. Periodic summaries of the most important hospital-acquired pathogens, including their antimicrobial susceptibility profiles, should be produced by the clinical microbiological laboratory and made available to the local infection control team. This exercise is greatly facilitated if laboratory test results are stored electronically, and if programmes for extracting relevant data are available. Surveillance of selected hospital-acquired pathogens in the local clinical microbiological laboratory should, if possible, take place in close cooperation with reference laboratories. The clinical microbiological laboratory may send strains to a central reference laboratory, or may transmit locally produced laboratory data to a central database. An example of this is the national S. aureus database maintained at the State Serum Institute, which has received strains and data from local clinical microbiological laboratories for more than 30 years. This database provides invaluable information about staphylococcal epidemiology in Denmark (phage types, antibiotic susceptibility, etc.).13 Several microbiology laboratories contribute to the national surveillance of antimicrobial resistance by reporting data to the Danish Integrated Antimicrobial Resistance Monitoring and Research Programme (DANMAP). This programme integrates data on antimicrobial consumption and antimicrobial resistance in bacteria from humans and food animals.18 National
standards
of infection
control
The recent years’ emphasis on quality assurance and infection control has led to discussions on the adequacy of the present organization. Despite limited
Microbiology
laboratory
and infection
s53
control
resources it has managed to solve most basic problems related to infection control; however, it is unlikely to be ready to face future requirements for standardization and documentation of quality. Therefore a national standard of infection control is being prepared with the overall aim of strengthening infection control, both in hospitals and in primary health care. It consists of two elements: a main standard, which describes the requirements for the management system, and 12 subsidiary standards, which describe the requirements for special areas of infection control. The main standard consists of four process-related elements, defining management responsibility, guidance on resources, guidance on infection control measures, and measurement, analysis and improvement. Together these four elements constitute an audit circle. The 12 subsidiary standards deal with all major areas of infection control. They comprise general practice, hand hygiene, intravenous catheters, surveillance and investigation of outbreaks, surgical site infections, urine continence aids, urinary catheters, textiles, purchase and maintenance of equipment, cleaning and quality control, foodstuffs and dental clinics. The contents of the 12 subsidiary standards are based on existing guidelines; however, the main standard is largely innovative. The main purpose of the latter is to secure compliance with guidelines, which is the weak point of the present organization. It is for the county councils and local hospitals to decide, whether or not they will introduce the standards. Furthermore, they are free to decide, how many of the standards from the package they wish to introduce. The only obligation is that as a minimum they must introduce the standard defining the requirements for the management plus one of the subsidiary standards.
Introducing the standards implies that there should be more focus on management and on identification and correction of errors. In consequence the demands for surveillance and audit will increase substantially. In order to meet this, the local infection control organizations will need more manpower and equipment. In particular there will be a need for more infection control nurses. Furthermore many clinical microbiologists will need to specialize and dedicate all their working time to infection control. This raises the question as to whether infection control should be kept as a part of clinical microbiology, or form an organization of its own. The advantages of a separate organization are that infection control is accorded a higher profile and has greater impact on the management system. However, it is not clear that this will lead to higher quality. The disadvantages are those of a more bureaucratic system with an administrative barrier between the diagnostic laboratory and the infection control organization. If infection control moves from the hands of clinical microbiologists, who include the diagnosis and treatment of infections in their daily work, then there is a risk that the present close contacts with clinicians will be weakened. The consequence of this may be that clinicians become less compliant. Considering the advantages and disadvantages it still seems most appropriate to maintain infection control integrated within clinical microbiology. What is needed is clinical microbiologists, who will specialize and dedicate more time to infection control. This can be achieved within the existing organizing framework by supplementary training, and by providing a more precise job description for microbiologists working within infection control.
References Discussion Infection control in Denmark is run with few resources. There are very few people employed fulltime in infection control. In fact these comprise only the infection control nurses, of whom there are on average two per county. They typically cover up to 2000 hospital beds, in addition to nursing homes and other institutions in primary health care. Despite low budgets, the present organization has managed to solve all basic problems related to infection control. However, it is evident that it is not ready to meet the additional work load caused by new standards.
Kolmos HJ. Interaction between the microbiology laboratory and clinician: what the microbiologist can provide. J Hasp Infect 1999; 43(Suppl): S285-S291. Kolmos HJ, Andersen KEH. Peritonitis with Pseudomonad aeruginosa in hospital patients treated with peritoneal dialysis. Stand 3’ Infect Dis 1979; 11: 207-210.
Siboni K, Olsen H, Ravn E et al. Pseudomonas cepacia in 16 non-fatal cases of postoperative bacteremia derived from intrinsic contamination of the anaesthetic fentanyl. ScandJ Infect Dis 1979; 11: 39-45. Espersen F, Nielsen PB, Lund K, Sylvest B, Jensen K. Hospital-acquired infections in a burn unit caused by an imvorted strain of Staahvlococcus aureus with
554
5.
6.
7.
8.
9.
10.
11.
12.
H. J. Kolmos
unusual multiresistance. J Hyg Camb 1982; 88: 535-541. Gahrn-Hansen B, Alstrup P, Dessau R et al. Outbreak of infection with Achromobacter xylosoxidans from contaminated intravascular pressure transducers. J Hosp Infect 1988; 12: 1-6. Ravn P, Lundgren JD, Kjaeldgaard P et al. Nosocomial outbreak of crytosporidiosis in AIDS patients. BMJ 1991; 302: 277-280. Kolmos HJ, Svendsen RN, Nielsen SV. The Surgical team as a source of postoperative wound infections caused by Streptococcus pyogenes. J Hosp Infect 1997; 35: 207-214. Kolmos HJ, Lerche A, Kristoffersen K, Rosdahl VT. Pseudo-outbreak of Pseudomonas aeruginosa in HIVinfected patients undergoing fiberoptic bronchoscopy. ScandJ Infect Dis 1994; 26: 653-657. Heltberg 0, Skov F, Gerner-Smidt P et al. Nosocomial epidemic of Serrutia marcescens septicemia ascribed to contaminated blood transfusion bags. Transfusion 1993; 33: 221-227. Kolmos HJ, Thuesen B, Nielsen SV, Lohmann M, Kristoffersen K, Rosdahl VT. Outbreak of infection in a burns unit due to Pseudomonas aeruginosa originating from contaminated tubing used for irrigation of patients r Hosp Infect 1993; 24: 11-21. Hansen L, Kolmos HJ, Siboni K. Detection of cumulations of infections over a three-year period using electronic data processing. Dan Med Bull 1978; 25: 253-257. Gerner-Smidt P, Hansen L, Knudsen A, Siboni K, Sogaard I. Epidemic spread of Acinetobacter
13.
14.
15.
16.
17.
18.
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