Staphylococcus aureus kolonisatie, dragerschap en transmissie

In this thesis, colonization, carriage and transmission of Staphylococcus aureus (S. aureus) were studied. A novel experimental decolonization and carriage model in rhesus macaques (Macaca mulatta) was set up. We showed that we could decolonize the nose of rhesus macaques that carried S. aureus, for a period of 10 weeks or more and we were able to inoculate the noses of the rhesus macaques with human S. aureus strain 8325–4. Another study with the human inoculation model was performed and methicillin-susceptible S. aureus (MSSA) strain 5062 of bovine origin (ST398, CC398) was found capable of surviving in the human nose for at least 21 days and it successfully outcompeted a human strain 1036 (ST931, CC8). We investigated, using whole-genome sequencing (WGS), whether nosocomial acquisition of S. aureus via healthcare workers (HCWs) occurred in neonates admitted to a neonatal intensive care unit (NICU). We also studied whether transmission and the presence of specific virulence genes support the occurrence of neonatal bloodstream infections. With our data, we can confirm that HCWs might be an important reservoir and link in the transmission of MSSA to neonates and this could partly explain the occurrence of neonatal S. aureus bacteremia