title: An outbreak of severe infections with community-acquired MRSA carrying the Panton-Valentine leukocidin following vaccination.
abstract: BACKGROUND
  Infections with community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) are emerging worldwide. We investigated an outbreak of severe CA-MRSA infections in children following out-patient vaccination.
  
  
  RESULTS
  We carried out a field investigation after adverse events following immunization (AEFI) were reported. We reviewed the clinical data from all cases. S. aureus recovered from skin infections and from nasal and throat swabs were analyzed by pulse-field gel electrophoresis, multi locus sequence typing, PCR and microarray. In May 2006, nine children presented with AEFI, ranging from fatal toxic shock syndrome, necrotizing soft tissue infection, purulent abscesses, to fever with rash. All had received a vaccination injection in different health centres in one District of Ho Chi Minh City. Eight children had been vaccinated by the same health care worker (HCW). Deficiencies in vaccine quality, storage practices, or preparation and delivery were not found. Infection control practices were insufficient. CA-MRSA was cultured in four children and from nasal and throat swabs from the HCW. Strains from children and HCW were indistinguishable. All carried the Panton-Valentine leukocidine (PVL), the staphylococcal enterotoxin B gene, the gene complex for staphylococcal-cassette-chromosome mec type V, and were sequence type 59. Strain HCM3A is epidemiologically unrelated to a strain of ST59 prevalent in the USA, although they belong to the same lineage.
  
  
  CONCLUSIONS
  We describe an outbreak of infections with CA-MRSA in children, transmitted by an asymptomatic colonized HCW during immunization injection. Consistent adherence to injection practice guidelines is needed to prevent CA-MRSA transmission in both in- and outpatient settings.
authors.affiliation: Pediatric Hospital No. 1, Ho Chi Minh City, Viet Nam.
authors.forename: Chi Thuong
authors.initials: CT
authors.lastname: Tang
authors.forename: Dac Tho
authors.initials: DT
authors.lastname: Nguyen
authors.forename: Thi Hoa
authors.initials: TH
authors.lastname: Ngo
authors.forename: Thi Minh Phuong
authors.initials: TM
authors.lastname: Nguyen
authors.forename: Van Tuan
authors.initials: VT
authors.lastname: Le
authors.forename: Song Diep
authors.initials: SD
authors.lastname: To
authors.forename: Jodi
authors.initials: J
authors.lastname: Lindsay
authors.forename: The Dung
authors.initials: TD
authors.lastname: Nguyen
authors.forename: Van Cam
authors.initials: VC
authors.lastname: Bach
authors.forename: Quoc Thinh
authors.initials: QT
authors.lastname: Le
authors.forename: Thanh Hai
authors.initials: TH
authors.lastname: Le
authors.forename: Dieu Linh
authors.initials: DL
authors.lastname: Le
authors.forename: James
authors.initials: J
authors.lastname: Campbell
authors.forename: Thi Kim Tien
authors.initials: TK
authors.lastname: Nguyen
authors.forename: Van Vinh Chau
authors.initials: VV
authors.lastname: Nguyen
authors.forename: Joshua
authors.initials: J
authors.lastname: Cockfield
authors.forename: Truong Giang
authors.initials: TG
authors.lastname: Le
authors.forename: Van Nghiem
authors.initials: VN
authors.lastname: Phan
authors.forename: Hoang Son
authors.initials: HS
authors.lastname: Le
authors.forename: Tan Son
authors.initials: TS
authors.lastname: Huynh
authors.forename: Van Phung
authors.initials: VP
authors.lastname: Le
authors.forename: Megan
authors.initials: M
authors.lastname: Counahan
authors.forename: Adwoa
authors.initials: A
authors.lastname: Bentsi-Enchill
authors.forename: Richard
authors.initials: R
authors.lastname: Brown
authors.forename: James
authors.initials: J
authors.lastname: Simmerman
authors.forename: Tran Chinh
authors.initials: TC
authors.lastname: Nguyen
authors.forename: Tinh Hien
authors.initials: TH
authors.lastname: Tran
authors.forename: Jeremy
authors.initials: J
authors.lastname: Farrar
authors.forename: Constance
authors.initials: C
authors.lastname: Schultsz
mesh_terms: D000293:Adolescent; D001427:Bacterial Toxins / Q000378:metabolism*; D001428:Bacterial Vaccines / Q000008:administration & dosage*; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000382:microbiology; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D005098:Exotoxins / Q000378:metabolism*; D005260:Female; D006801:Humans; D007956:Leukocidins / Q000378:metabolism*; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D016133:Polymerase Chain Reaction; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D014744:Vietnam / Q000453:epidemiology