Enterococcus hirae biofilm formation on hospital material surfaces and effect of new biocides
Di Lodovico et al. Environmental Health and Preventive Medicine
Enterococcus hirae biofilm formation on hospital material surfaces and effect of new biocides
Silvia Di Lodovico 0
Valentina Cataldi 0
Emanuela Di Campli 0
Elisabetta Ancarani 0
Luigina Cellini 0
Mara Di Giulio 0
0 Department of Pharmacy, University “G. d'Annunzio” Chieti-Pescara , Chieti , Italy
Background: Nowadays, the bacterial contamination in the hospital environment is of particular concern because the hospital-acquired infections (HAIs), also known as nosocomial infections, are responsible for significant morbidity and mortality. This work evaluated the capability of Enterococcus hirae to form biofilm on different surfaces and the action of two biocides on the produced biofilms. Methods: The biofilm formation of E. hirae ATCC 10541 was studied on polystyrene and stainless steel surfaces through the biomass quantification and the cell viability at 20 and 37 °C. The effect of LH IDROXI FAST and LH ENZYCLEAN SPRAY biocides on biomasses was expressed as percentage of biofilm reduction. E. hirae at 20 and 37 °C produced more biofilm on the stainless steel in respect to the polystyrene surface. The amount of viable cells was greater at 20 °C than with 37 °C on the two analyzed surfaces. Biocides revealed a good anti-biofilm activity with the most effect for LH ENZYCLEAN SPRAY on polystyrene and stainless steel at 37 °C with a maximum biofilm reduction of 85.72 and 86.37%, respectively. Results: E. hirae is a moderate biofilm producer depending on surface material and temperature, and the analyzed biocides express a remarkable antibiofilm action. Conclusion: The capability of E. hirae to form biofilm can be associated with its increasing incidence in hospital-acquired infections, and the adoption of suitable disinfectants is strongly recommended.
Biocidal products; Biofilm; Enterococcus hirae; Hospital-acquired infections (HAIs); Sanitation
Background
Nowadays, the bacterial contamination in the hospital
environment is of particular concern because the
hospitalacquired infections (HAIs), also known as nosocomial
infections, are responsible for significant morbidity and
mortality [
1
]. The European Centre for Disease Prevention
and Control (ECDC) estimated that, in the EU, each year,
about 4, 100,000 patients acquired a healthcare-associated
infection, resulting in 110, 000 deaths [
2
].
According to ECDC, HAIs are infections contracted in
the healthcare setting (e.g., inpatient hospital admission
or same-day surgery) that can originate from different
sources such as external environment, infected patients,
healthcare staff that may be infected, contaminated
items (food, water, medications, devices, and
equipment), or droplets containing microbes [
3, 4
].
It is well known that bacteria, exposed to various stresses
(e.g., antibiotics, nutrient limitation, non-permissive
temperature), can express the ability to form multicellular
organizations as a network of cell-to-cell interactions
attached to each other and/or to surfaces, called biofilms
that permit survival in adverse environments [5], and that
are difficult to treat, resulting in an enormous impact on
healthcare [
6–9
].
Therefore, the capability of bacteria to grow on biofilm
mode surfaces is in another aspect to consider in the
clinical contamination.
Actually, equipment for sanitation and hand-touch
surfaces sanitizing/sterilization together with hand washing
of visitors to patients, and all medical personnel are the
most effective ways to contrast nosocomial infections [
10
].
Consequently, hospital disinfection policies play an
mportant role in the control of HAIs [
11, 12
]. “Biocidal
products are those that are intended to destroy, render
harmless, prevent the action of, or otherwise exert a
controlling effect on any harmful organism by chemical or
biological means; examples include disinfectants,
preservatives, antiseptics, pesticides, herbicides, fungicides and
insecticides” (Biocides Directive 98/8/EC 1998) [13]. They
are used widely for the disinfection of surfaces and
equipment, and for sterilization of medical devices.
Enterococci, previously included among gut
commensals of humans and animals, in the last years, have
acquired the role of common nosocomial pathogens (the
third leading source of nosocomial infection), causing
urinary tract infections, endocarditis, peritonitis, and
bacteremia [
14
]. Among these, Enterococcus hirae,
proposed as a new test germ within the framework of the
procedures for the European standardization of chemical and
antiseptic agents for evaluation and validation of
disinfectant products (EN14561:2006) [
15
], has been recently
described as an emergent nosocomial pathogen in HAIs
[
16, 17
]. Despite, human E. hirae infection is extended to
be 1–3% of the Enterococcus spp. infections detected in
clinical practice [18], and an emerging role of source of
serious illness can be attributed to this microorganism
responsible (...truncated)