Molecular surveillance of methicillin-susceptible Staphylococcus aureus at a neonatal intensive care unit in Brazil

• Published in: American journal of infection control Vol. 37; no. 7; pp. 574 - 579
• Main Authors: Silva, Helisângela de Almeida, PhD, Pereira, Eliezer M., MSc, Schuenck, Ricardo P., PhD, Pinto, Ricardo C.M., PhD, Abdallah, Vânia O.S., MD, PhD, Santos, Kátia Regina N., PhD, Gontijo-Filho, Paulo P., MD, PhD
• Format: Journal Article
• Language: English
• Published: New York, NY Mosby, Inc 01-09-2009; Elsevier; Mosby-Year Book, Inc
• Subjects: Anti-Bacterial Agents - pharmacology; Bacterial diseases; Biological and medical sciences; Brazil - epidemiology; Carrier State - epidemiology; Carrier State - microbiology; Carrier State - transmission; Case-Control Studies; Cross Infection - epidemiology; Cross Infection - microbiology; Cross Infection - transmission; Disease transmission; DNA, Bacterial - genetics; Electrophoresis, Gel, Pulsed-Field; Epidemiology; Epidemiology. Vaccinations; Female; General aspects; Genotype; Genotype & phenotype; Human bacterial diseases; Humans; Incidence; Infant, Newborn; Infant, Premature; Infection Control; Infectious Disease; Infectious diseases; Intensive care; Intensive Care Units, Neonatal - statistics & numerical data; Male; Medical sciences; Methicillin - pharmacology; methicillin-susceptible; Molecular Epidemiology; neonatal intensive care unit; neonates; Nosocomial infections; PFGE; Risk Assessment; Risk Factors; S. aureus; Sentinel Surveillance; Sepsis; Staphylococcal Infections - epidemiology; Staphylococcal Infections - microbiology; Staphylococcal Infections - transmission; Staphylococcal infections, streptococcal infections, pneumococcal infections; Staphylococcus aureus - drug effects; Staphylococcus aureus - genetics; Staphylococcus infections; South America; Brazil; America; PFGE; S. aureus; neonates; methicillin-susceptible; neonatal intensive care unit; Human; Check; Intensive care unit; Infection; Prevention; Newborn; Surveillance; Bacteriosis; Bacteria; Micrococcales; Micrococcaceae; Staphylococcal infection; Staphylococcus aureus
• ISSN: 0196-6553; 1527-3296
• DOI: 10.1016/j.ajic.2008.10.021

Background We evaluated the relationship among hospital infection and colonization by methicillin-susceptible Staphylococcus aureus (MSSA), clonal spread, and associated risk factors in a neonatal intensive care unit (NICU) of the Uberlândia Federal University-affiliated hospital in Brazil. Methods Between February 2004 and June 2005, a longitudinal surveillance study was carried out in an NICU with neonates presenting infections, through both the NNIS system and S aureus punctual colonization prevalence inquests. Results The overall rate of infection incidence was 23/1000 patient-days. Of all the neonates assessed, 15 were infected and 15 colonized. Sepsis was the most frequent infection, whereas anterior nare was the most isolated site. Antibiotics use, central vascular catheter (CVC), and CVC use more than 7 days and its insertion by phlebotomy were the risk factors for colonization/infection. Molecular analysis showed polyclonal origin (12 genotypes), with predominance of a genotype (“B“), and clonal identity between colonization and infection samples. Conclusion The analysis by means of classical epidemiology and molecular techniques pointed out that methicillin-susceptible Staphylococcus aureus infections were associated with previous colonization by the pathogen, with evidence of horizontal transmission within the unit.