Outbreak of invasive group A streptococcal disease among children attending a day-care center.
BACKGROUND
Most cases of invasive group A streptococcal (GAS) disease arise sporadically in the community, but outbreaks of severe invasive GAS infections have been reported in closed environments, such as military populations, family communities and hospitals. An outbreak of invasive GAS disease involving 3 cases of streptococcal toxic shock syndrome (TSS), one with a fatal course, occurred among children attending a day-care center located in Cantabria, Northern Spain.


OBJECTIVE
To determine the characteristics of GAS isolates obtained from the outbreak environment.


METHODS
GAS isolates obtained from children attending the same day-care facility, staff members, and family contacts were assayed for emm typing, pulse-field gel electrophoresis (PFGE), and toxin-gene content. One isolate obtained from the fatal case was also characterized by multilocus sequence typing. Antimicrobial susceptibility testing was done. Strains from patients unrelated to the outbreak were included for comparison.


RESULTS
All GAS isolates from children attending the day-care center, including those from streptococcal TSS cases, shared the same emm type 4, genomic pattern by PFGE (A) and toxin-gene profile. Neither the emm type nor the PFGE pattern or toxin gene profile of the outbreak-associated strains were encountered among GAS isolated from household or staff contacts.


CONCLUSIONS
A clone of GAS belonging to emm type 4 and characterized by a specific PFGE pattern and toxin-gene profile was responsible for a community outbreak of streptococcal TSS disease in a child day-care center in Spain. This is the first day-care outbreak reported in our country.
Service of Microbiology, University Marqués de Valdecilla, Spain. micabj@humv.es
Jesus
J
Aguero
Manuel
M
Ortega-Mendi
Maria
M
Eliecer Cano
Alvaro
A
Gonzalez de Aledo
Jorge
J
Calvo
Luis
L
Viloria
Purificacion
P
Mellado
Teresa
T
Pelayo
Amparo
A
Fernandez-Rodriguez
Luis
L
Martinez-Martinez
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000942:Antigens, Bacterial / Q000235:genetics; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D001427:Bacterial Toxins / Q000235:genetics; D015373:Bacterial Typing Techniques; D002352:Carrier Proteins / Q000235:genetics; D002656:Child Day Care Centers; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000453:epidemiology / Q000382:microbiology; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D005838:Genotype; D006801:Humans; D007223:Infant; D008826:Microbial Sensitivity Tests; D017422:Sequence Analysis, DNA; D012772:Shock, Septic / Q000382:microbiology; D013030:Spain / Q000453:epidemiology; D013290:Streptococcal Infections / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*
D000900:Anti-Bacterial Agents; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001427:Bacterial Toxins; D002352:Carrier Proteins; D004269:DNA, Bacterial; C014689:streptococcal M protein