A persistent recurring cluster of meticillin-resistant Staphylococcus aureus (MRSA) colonizations in a special care baby unit: a matched case-control study.
MRSA
Matched case–control study
Prolonged outbreak
Special care baby unit
Journal
The Journal of hospital infection
ISSN: 1532-2939
Titre abrégé: J Hosp Infect
Pays: England
ID NLM: 8007166
Informations de publication
Date de publication:
Dec 2020
Dec 2020
Historique:
received:
04
09
2020
accepted:
26
09
2020
pubmed:
5
10
2020
medline:
14
7
2021
entrez:
4
10
2020
Statut:
ppublish
Résumé
Between August 2016 and November 2019, a cluster of babies colonized with meticillin-resistant Staphylococcus aureus (MRSA) was reported in a special care baby unit in northern England. A case-control study was performed to identify the source and prevent further cases. Cases were admitted neonates colonized or infected with MRSA (spa type t316). A retrospective case-control study was performed with two matched controls per case. Exposures were determined by medical record review. Cases were compared with controls using conditional logistic regression. Environmental investigations and staff screening were undertaken. Thirty-one colonized cases were identified across the 3-year period, with no infections reported. Thirteen of the 31 cases were sequenced and were within a cluster of 25 single nucleotide polymorphisms, consistent with exposure to a common source over a prolonged period. Most MRSA cases had a prior negative screen (N=22, 71%). Environmental sampling and staff screening were performed on several occasions. In the analytical study, 31 cases were compared with 62 controls. One ward location and one healthcare worker were identified as significant exposures in the multi-variable analysis. Due to the sporadic nature of the colonizations, it was hypothesized that MRSA was being introduced intermittently, likely by a colonized healthcare worker, with possible transmission between infants also occurring within each temporal cluster. It is recommended that transiently colonized healthcare workers should be considered as a source of MRSA during outbreaks. This study highlights the importance of analytic epidemiological studies in persistent outbreaks of MRSA.
Sections du résumé
BACKGROUND
BACKGROUND
Between August 2016 and November 2019, a cluster of babies colonized with meticillin-resistant Staphylococcus aureus (MRSA) was reported in a special care baby unit in northern England.
AIM
OBJECTIVE
A case-control study was performed to identify the source and prevent further cases.
METHODS
METHODS
Cases were admitted neonates colonized or infected with MRSA (spa type t316). A retrospective case-control study was performed with two matched controls per case. Exposures were determined by medical record review. Cases were compared with controls using conditional logistic regression. Environmental investigations and staff screening were undertaken.
FINDINGS
RESULTS
Thirty-one colonized cases were identified across the 3-year period, with no infections reported. Thirteen of the 31 cases were sequenced and were within a cluster of 25 single nucleotide polymorphisms, consistent with exposure to a common source over a prolonged period. Most MRSA cases had a prior negative screen (N=22, 71%). Environmental sampling and staff screening were performed on several occasions. In the analytical study, 31 cases were compared with 62 controls. One ward location and one healthcare worker were identified as significant exposures in the multi-variable analysis.
CONCLUSIONS
CONCLUSIONS
Due to the sporadic nature of the colonizations, it was hypothesized that MRSA was being introduced intermittently, likely by a colonized healthcare worker, with possible transmission between infants also occurring within each temporal cluster. It is recommended that transiently colonized healthcare workers should be considered as a source of MRSA during outbreaks. This study highlights the importance of analytic epidemiological studies in persistent outbreaks of MRSA.
Identifiants
pubmed: 33011307
pii: S0195-6701(20)30454-0
doi: 10.1016/j.jhin.2020.09.029
pii:
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
774-781Informations de copyright
Crown Copyright © 2020. Published by Elsevier Ltd. All rights reserved.