232
and silver ions (0.04mg∙L-
1
) to run the disinfection of thewater ismore efficient
than the periodical rinsing with hot water at 77 °C to control
Legionella
in
reservoirs and water distribution systems in hospitals. Kusnetsov
et al
. (2001)
concluded that the regular use of copper ions (84µg∙L
-1
) and silver ions (3µg∙L
-1
)
in water distribution systems in hospitals can control the presence of
Legionella
provided if water is not stagnated at the interior of the pipes for long periods.
The authors also verified that with the reduction of the silver concentration
to values lower than a 2 µg∙L
-1
, cells of
Legionella
were again isolated in the
showers served by this water. However, other studies mentioned by Kusnetsov
et al
. (2001) show that it is necessary to use higher concentrations of copper
(400 µg∙L
-1
) and silver (40 µg∙L
-1
), the same values recommended by the British
authorities for the control of
Legionella
in hot water systems. In case amoebae
control is necessary, you should use, simultaneously, 800 µg Cu∙L
-1
, 80 µg Ag∙L
-1
and 1 mg∙L
-1
of free chlorine.
In turn, Leoni
et al
. (2005) found that the use of copper pipes help to control
Legionella
spp. Table 1, adapted fromLeoni
et al
. (2005) illustrates the influence
of the copper concentration in the water and the percentage of positive samples
for these microorganisms. Rogers
et al
. (1994) had already evidenced that
copper surfaces inhibit the formation of biofilms and limit themultiplication of
Legionella pneumophila
.These authors recommend the use of copper plumbing
to reduce the risk of outbreaks caused by
Legionella
, particularly when it is not
possible to keep the water temperature at 60 °C.
Lin
et al
. (2011) conducted an extensive bibliographic review concerning
the control processes of
Legionella
in hospitals. In the case of the use of copper
and silver ions, they recommend the use of a copper concentration between
0.20 and 0.80 mg∙L
-1
, and between 0.01 and 0.08 mg∙L
-1
of silver ions to
eradicate
Legionella
from the water distribution system of hospitals. In case of
