The two units where the outbreak investigation was performed
took necessary action with regards to updating written
procedures, training of personnel and surface decontamination.
However, one of the reasons for this prolonged outbreak
could be that surveillance cultures of patients and staff were
not introduced before ward closure, and patients with undetected
MRAB colonization could have served as a reservoir.
Lack of screening samples from staff and patients was a limitation
of our study. Only after temporary closure of wards had
been instituted, and full decontamination of the departments
using VHP performed, was the outbreak controlled. Unfortunately,
a second outbreak occurred eight months after the
first. We do not know the source of the second outbreak. Bothde novo introduction of the epidemic strain through transfer of
a colonized patient and undetected persistence of the
epidemic strain in the hospital environment are possible
although none of the multiple environmental samples had
yielded a positive result. On the other hand, the control
measures had at least some effect since no MRAB was isolated
from patients’ blood during the second outbreak. It is therefore
reasonable to think that some procedural errors were eliminated
by strengthening intravascular catheter care and contact
isolation, especially hand hygiene, including the implementation
theWorld Health Organization’s ‘My five moments for hand
hygiene’