Journal of Hospital Infection ( 1990) 15, 173-l 76
SHORT REPORTS
Streptococclrs
an outbreak
pyogenes:
on a burns
unit I. A. Burnett*
and P. Normant
*Department of Medical Microbiology and tPublic Health Laboratory, Northern General Hospital, Shefield Accepted for publication 26 October 1989 Summary: An outbreak of infection with Streptococcus pyogenes (Group A beta-haemolytic streptococcus) on a bums unit is described. The control measures taken are outlined, and the route of spread of infection is discussed along with possible preventative measures. Keywords: Streptococcus pyogenes; burns unit.
Introduction Outbreaks of Streptococcus pyogenes (Group A beta-haemolytic streptococcus) infection on specialist units are well documented (Nicolle et al., 1986). In burns patients they can cause local infection, graft failure and occasionally septicaemia (Cason, 1981; J ac k son et al., 1951). We report here an outbreak of group A streptococcal infection involving four patients, six relatives of the index case and four members of staff on the Burns Unit at the Northern General Hospital in Sheffield. We outline the mode of spread of the organism and suggest measures to prevent further outbreaks. Epidemiological
investigation
Description of the unit The Burns Unit was opened in April 1986; it can accommodate 15 patients in six double and three single rooms, each room having its own toilet facilities and a handwash basin, plus an ante-room with a handwash basin. burns are taken routinely twice weekly which Swabs from patients’ normally coincides with change of dressing (Lowbury, 1979); nose, throat and burn swabs are also taken on admission (Lawrence, 1985) and examined before the patient is allowed to mix socially with other patients. Correspondence to: Dr Hospital, Sheffield. 01954701/90/020173+04
I. A. Burnett,
Department
of Medical
Microbiology,
The
Royal
0 1990 The Hospital
$03.@3/0
173
Hallamshire
Infection
Society
174
I. A. Burnett
and P. Norman
Time course of the outbreak In June 1988-a nurse from the Burns Unit reported to Occupational Health with an area of cellulitis on his forearm. A skin swab grew S. pyogenes. On the following day another nurse from the same unit also reported with a forearm lesion, a skin swab from which grew the same organism. At the same time it was noted that routine swabs taken from burns to the axilla and thigh of a two-year-old male patient of Asian origin were also growing S. pyogenes. The nose and burn swabs taken on admission had proved negative but it had been impossible to obtain a throat swab owing to the child’s distress; a subsequent throat swab grew S. pyogenes. Two days later a third and fourth nurse reported with skin lesions, one with a discharging pustule on her face, and another with an infected whitlow. Swabs grew S. pyogenes, as did screening swabs from the burns of an adult male patient. On the tenth day after the first isolate was discovered a third adult female patient was found to be colonized by S. pyogenes. One further case came to light when a three-year-old boy who had undergone skin grafting and had been discharged as the first positive swabs appeared, was found at out-patient clinic a month later to have inflammation over the graft sites. Swabs grew S. pyogenes and, following antibiotic therapy, the problem was resolved. Screening measures Throat swabs were taken from all staff and patients, and also from the immediate family of the index case, six of the latter proving positive. Swabs were taken from patients’ burns and from any skin lesions on members of staff. A number of swabs were taken from the communal baby bath, the toys kept with the bath, the adult bath and the hoist used for lifting adults into the bath. The one taken from the rim of the baby bath grew S. pyogenes but, as only the index case had used the bath, it was not felt to be directly implicated in patient to patient spread of the organism. All isolates of S. pyogenes were subsequently typed and found to be of Griffith type T12M22.
Control
measures
General measures All patients whose swabs grew S. pyogenes were barrier nursed in a single room, and were discharged as soon as possible. All members of staff with sore throats or skin lesions whose swabs grew S. pyogenes were excluded from work until the lesions had cleared and a repeat swab was negative. Relatives of the index case whose throat swabs were positive were also excluded from the unit. Antibiotic therapy Patients infected with S. pyogenes received oral antibiotic
therapy
consisting
Streptococcus
pyogenes
on a burns unit
175
of phenoxymethylpenicillin 500mg q.d.s., or 250mg for a child, plus flucloxacillin 500 mg q.d.s. or 125 mg respectively if the patient was also colonized by Staphylococcus aureus. In the case of the patient with 50% burns, intravenous benzylpenicillin, 600 mg q.d.s., and flucloxacillin, 500 mg q.d.s. were given for 48 h before oral therapy was instituted. If the patient was allergic to penicillin, erythromycin 500mg q.d.s. was used instead. When one week’s oral therapy failed to eradicate the organism from the index case, mupirocin cream was applied to his burns, resulting in bacteriological clearance. Infected members of staff received antibiotics from their general practitioners. Relatives of the index case whose throat swabs grew S. pyogenes also received antibiotics from their general practitioner. Use of gowns It was noted that short sleeved gowns that left the forearm exposed were being used for barrier nursing, bathing patients and bottle feeding children. Since two nurses had presented with forearm lesions, advice to use only long-sleeved gowns was given. Outcome In the early stages of the outbreak the Burns Unit remained open to admissions, as it was felt that the design of the unit facilitated barrier nursing enabling rapid control of an outbreak. When however, a third colonized patient was found on the tenth day after the first isolate, the unit was closed to new admissions. It was reopened one week later; in the intervening period no further cases of S. pyogenes infection were reported, and the ward underwent disinfection with 2% stericol. Discussion
A number of lessons can be learned from this outbreak. Firstly the importance of taking routine surveillance swabs on a Burns Unit is underlined. If the index case had had a throat swab taken on admission, the streptococcus might have been detected at an earlier point. Because of the considerable risk to burned patients infected with S. pyogenes, particularly the likelihood of failure of skin grafting, we treat with antibiotics any patient admitted to the Burns Unit whose nose or throat swab grows this organism, even if they are asymptomatically colonized. A similar policy is pursued with the immediate family of a positive patient. Secondly the need to wear long-sleeved rather than short-sleeved gowns became apparent. Contact spread is widely recognized to be an important route of cross-infection within hospitals (Ayliffe & Lilly, 1985). All the nursing staff involved had had contact with the index case and one or more other affected patients. The authors believe that the nursing staff with
176
I. A. Burnett
and P. Norman
forearm lesions became infected whilst feeding or bathing the index case with exposed arms. They may have passed the infecting organism to other patients in a similar manner. The wearing of either short-sleeved gowns or plastic aprons with gloves, leaving the forearm exposed, is common practice on many specialist units and will usually provide adequate protection. However, burns patients often have large areas of damaged skin not covered by dressings. Contact between these areas and the bare arm of the attending nurse is inevitable. The importance of thorough handwashing has been stressed on many occasions (Taylor, 1978; Lawrence, 1985), but emphasis tends to be placed upon cleansing of the hands rather than the forearms. On this unit nursing staff are advised to include thorough washing of the forearms in their routine handwash procedure, but at busy times it is easy for this practice to break down. Unfortunately the problem is not always solved by using long-sleeved gowns. The sleeves of these inevitably become soaked when bathing patients, making their use unacceptable to nursing staff. We have enquired into the possibility of obtaining long-sleeved gloves for these situations, but exhaustive enquiries to glove manufacturers have failed to reveal a satisfactory source. Long-sleeved gloves are available for veterinary surgeons; they are ill-fitting and are not sold sterile. Elbow length sterile gloves are also marketed for obstetric purposes, but in our opinion lack the sensitivity necessary for careful handling of patients. We feel that appropriate long-sleeved, prepackaged sterile gloves should now be available for patient care, though long-sleeved gowns and careful forearm washing must remain the foundation of infection control when patients have extensive areas of damaged skin. References Ayliffe, G. A. J. & Lilly, H. A. (1985). C ross-infection and its prevention.Journal of Hospital Infection 6 (Suppl. B), 47-57. Cason, J. S. (1981). Treatment of Burns. London: Chapman & Hall. Jackson, D. M., Lowbury, E. J. L. & Topley, E. (1951). Chemotherapy of Streptococcus pyogenes infection of burns. Lancet 2, 705-711. Lawrence, J. C. (1985). The bacteriology of burns. Journal of Hospital Infection 6 (Suppl. B), 3-17. Lowbury, E. J. L. (1979). Wits versus genes: the continuing battle against infection. Journal of Trauma 19, 33-45. Nicolle, L. E., Hume, K., Sims, H., Rosenal, T. & Sandham, D. (1986). An outbreak of Group A streptococcal bacteremia in an intensive care unit. Infection Control 7, 177-80. Taylor, L. J. (1978). An evaluation of handwashing techniques-l. Nursing Times January 12, s&55.
SHORT REPORTS
Streptococclrs
an outbreak
pyogenes:
on a burns
unit I. A. Burnett*
and P. Normant
*Department of Medical Microbiology and tPublic Health Laboratory, Northern General Hospital, Shefield Accepted for publication 26 October 1989 Summary: An outbreak of infection with Streptococcus pyogenes (Group A beta-haemolytic streptococcus) on a bums unit is described. The control measures taken are outlined, and the route of spread of infection is discussed along with possible preventative measures. Keywords: Streptococcus pyogenes; burns unit.
Introduction Outbreaks of Streptococcus pyogenes (Group A beta-haemolytic streptococcus) infection on specialist units are well documented (Nicolle et al., 1986). In burns patients they can cause local infection, graft failure and occasionally septicaemia (Cason, 1981; J ac k son et al., 1951). We report here an outbreak of group A streptococcal infection involving four patients, six relatives of the index case and four members of staff on the Burns Unit at the Northern General Hospital in Sheffield. We outline the mode of spread of the organism and suggest measures to prevent further outbreaks. Epidemiological
investigation
Description of the unit The Burns Unit was opened in April 1986; it can accommodate 15 patients in six double and three single rooms, each room having its own toilet facilities and a handwash basin, plus an ante-room with a handwash basin. burns are taken routinely twice weekly which Swabs from patients’ normally coincides with change of dressing (Lowbury, 1979); nose, throat and burn swabs are also taken on admission (Lawrence, 1985) and examined before the patient is allowed to mix socially with other patients. Correspondence to: Dr Hospital, Sheffield. 01954701/90/020173+04
I. A. Burnett,
Department
of Medical
Microbiology,
The
Royal
0 1990 The Hospital
$03.@3/0
173
Hallamshire
Infection
Society
174
I. A. Burnett
and P. Norman
Time course of the outbreak In June 1988-a nurse from the Burns Unit reported to Occupational Health with an area of cellulitis on his forearm. A skin swab grew S. pyogenes. On the following day another nurse from the same unit also reported with a forearm lesion, a skin swab from which grew the same organism. At the same time it was noted that routine swabs taken from burns to the axilla and thigh of a two-year-old male patient of Asian origin were also growing S. pyogenes. The nose and burn swabs taken on admission had proved negative but it had been impossible to obtain a throat swab owing to the child’s distress; a subsequent throat swab grew S. pyogenes. Two days later a third and fourth nurse reported with skin lesions, one with a discharging pustule on her face, and another with an infected whitlow. Swabs grew S. pyogenes, as did screening swabs from the burns of an adult male patient. On the tenth day after the first isolate was discovered a third adult female patient was found to be colonized by S. pyogenes. One further case came to light when a three-year-old boy who had undergone skin grafting and had been discharged as the first positive swabs appeared, was found at out-patient clinic a month later to have inflammation over the graft sites. Swabs grew S. pyogenes and, following antibiotic therapy, the problem was resolved. Screening measures Throat swabs were taken from all staff and patients, and also from the immediate family of the index case, six of the latter proving positive. Swabs were taken from patients’ burns and from any skin lesions on members of staff. A number of swabs were taken from the communal baby bath, the toys kept with the bath, the adult bath and the hoist used for lifting adults into the bath. The one taken from the rim of the baby bath grew S. pyogenes but, as only the index case had used the bath, it was not felt to be directly implicated in patient to patient spread of the organism. All isolates of S. pyogenes were subsequently typed and found to be of Griffith type T12M22.
Control
measures
General measures All patients whose swabs grew S. pyogenes were barrier nursed in a single room, and were discharged as soon as possible. All members of staff with sore throats or skin lesions whose swabs grew S. pyogenes were excluded from work until the lesions had cleared and a repeat swab was negative. Relatives of the index case whose throat swabs were positive were also excluded from the unit. Antibiotic therapy Patients infected with S. pyogenes received oral antibiotic
therapy
consisting
Streptococcus
pyogenes
on a burns unit
175
of phenoxymethylpenicillin 500mg q.d.s., or 250mg for a child, plus flucloxacillin 500 mg q.d.s. or 125 mg respectively if the patient was also colonized by Staphylococcus aureus. In the case of the patient with 50% burns, intravenous benzylpenicillin, 600 mg q.d.s., and flucloxacillin, 500 mg q.d.s. were given for 48 h before oral therapy was instituted. If the patient was allergic to penicillin, erythromycin 500mg q.d.s. was used instead. When one week’s oral therapy failed to eradicate the organism from the index case, mupirocin cream was applied to his burns, resulting in bacteriological clearance. Infected members of staff received antibiotics from their general practitioners. Relatives of the index case whose throat swabs grew S. pyogenes also received antibiotics from their general practitioner. Use of gowns It was noted that short sleeved gowns that left the forearm exposed were being used for barrier nursing, bathing patients and bottle feeding children. Since two nurses had presented with forearm lesions, advice to use only long-sleeved gowns was given. Outcome In the early stages of the outbreak the Burns Unit remained open to admissions, as it was felt that the design of the unit facilitated barrier nursing enabling rapid control of an outbreak. When however, a third colonized patient was found on the tenth day after the first isolate, the unit was closed to new admissions. It was reopened one week later; in the intervening period no further cases of S. pyogenes infection were reported, and the ward underwent disinfection with 2% stericol. Discussion
A number of lessons can be learned from this outbreak. Firstly the importance of taking routine surveillance swabs on a Burns Unit is underlined. If the index case had had a throat swab taken on admission, the streptococcus might have been detected at an earlier point. Because of the considerable risk to burned patients infected with S. pyogenes, particularly the likelihood of failure of skin grafting, we treat with antibiotics any patient admitted to the Burns Unit whose nose or throat swab grows this organism, even if they are asymptomatically colonized. A similar policy is pursued with the immediate family of a positive patient. Secondly the need to wear long-sleeved rather than short-sleeved gowns became apparent. Contact spread is widely recognized to be an important route of cross-infection within hospitals (Ayliffe & Lilly, 1985). All the nursing staff involved had had contact with the index case and one or more other affected patients. The authors believe that the nursing staff with
176
I. A. Burnett
and P. Norman
forearm lesions became infected whilst feeding or bathing the index case with exposed arms. They may have passed the infecting organism to other patients in a similar manner. The wearing of either short-sleeved gowns or plastic aprons with gloves, leaving the forearm exposed, is common practice on many specialist units and will usually provide adequate protection. However, burns patients often have large areas of damaged skin not covered by dressings. Contact between these areas and the bare arm of the attending nurse is inevitable. The importance of thorough handwashing has been stressed on many occasions (Taylor, 1978; Lawrence, 1985), but emphasis tends to be placed upon cleansing of the hands rather than the forearms. On this unit nursing staff are advised to include thorough washing of the forearms in their routine handwash procedure, but at busy times it is easy for this practice to break down. Unfortunately the problem is not always solved by using long-sleeved gowns. The sleeves of these inevitably become soaked when bathing patients, making their use unacceptable to nursing staff. We have enquired into the possibility of obtaining long-sleeved gloves for these situations, but exhaustive enquiries to glove manufacturers have failed to reveal a satisfactory source. Long-sleeved gloves are available for veterinary surgeons; they are ill-fitting and are not sold sterile. Elbow length sterile gloves are also marketed for obstetric purposes, but in our opinion lack the sensitivity necessary for careful handling of patients. We feel that appropriate long-sleeved, prepackaged sterile gloves should now be available for patient care, though long-sleeved gowns and careful forearm washing must remain the foundation of infection control when patients have extensive areas of damaged skin. References Ayliffe, G. A. J. & Lilly, H. A. (1985). C ross-infection and its prevention.Journal of Hospital Infection 6 (Suppl. B), 47-57. Cason, J. S. (1981). Treatment of Burns. London: Chapman & Hall. Jackson, D. M., Lowbury, E. J. L. & Topley, E. (1951). Chemotherapy of Streptococcus pyogenes infection of burns. Lancet 2, 705-711. Lawrence, J. C. (1985). The bacteriology of burns. Journal of Hospital Infection 6 (Suppl. B), 3-17. Lowbury, E. J. L. (1979). Wits versus genes: the continuing battle against infection. Journal of Trauma 19, 33-45. Nicolle, L. E., Hume, K., Sims, H., Rosenal, T. & Sandham, D. (1986). An outbreak of Group A streptococcal bacteremia in an intensive care unit. Infection Control 7, 177-80. Taylor, L. J. (1978). An evaluation of handwashing techniques-l. Nursing Times January 12, s&55.
