Oct 31, 2003

Filter Provides Legionella Barrier for Hospitals

Legionella Bacteria and Other Pathogens Blocked for High-Purity Water

p class=MsoNormal>Presence of the bacteria Legionella pneumophilia in
hospitals and nursing homes in the U.S. and Europe has been detected at an
alarming rate. Contaminated water has frequently been found to be the source.
Legionella is found naturally in water but multiplies in heating systems.

The growing problem of hospital water contaminated with
bacteria, fungi and protozoa can be harmful to patients, especially those with
compromised immune systems. These include surgical, cancer, burn, transplant,
chronic lung disease and HIV infected patients as well as the elderly and
newborns. Contaminated water has been found in a wide number of places
throughout hospitals from patient rooms to intensive care units and from
showers to humidifiers appearing most commonly in the cooling towers and
hot/warm water storage and systems. This has resulted in an increase in
nosocomial (hospital-acquired) infections, some of which are resistant to

Infection control experts in hospitals and medical
institutions are increasingly turning to point-of-use filtration as a
preventive measure to alleviate the problem of contaminated water systems.

Disinfecting water at a treatment plant or even at the point
of entry into a hospital does not solve the problem. Bacteria and other microorganisms
create biofilms (when they attach themselves to a surface as a colony) in
piping systems, faucets and showerheads. When the water meets the air, these
biofilms also can create an aerosolized germ that can be inhaled. Water
treatment methods including heat, chemical disinfection and ultraviolet
radiation do not reliably remove the biofilms that form.

Patient exposure to these potentially lethal microorganisms
in the hospital occurs while showering, bathing, drinking and ingesting ice as
well as from inhaling aerosols of contaminated water. Exposure also can occur
through contact with medical equipment such as tube feed bags, endoscopes and
bronchoscopes, which can become contaminated when rinsed with tap water, or
from the hands of healthcare personnel who have washed using tap water.

Although Legionella is the most recognized of all the
waterborne pathogens, there are many other microbes that are just as dangerous.

In an analysis conducted by Elias J. Anaissie, M.D., et.al.,
of the Myeloma and Transplantation Research Center, University of Arkansas for
Medical Sciences, the waterborne bacteria Pseudomonas aeruginosa is estimated
to cause about 1,400 pneumonia deaths in U.S. hospitals each year (Archives of
Internal Medicine, July 2002). Most recently, the medical community raised new
concern about the toxic mold Aspergillus found in hospital water systems. In a
newly reported study, this waterborne fungus was found to cause illness in
about 15 percent of immune compromised patients with a 50 percent fatality rate,
despite the use of traditional preventative measures.

In response to the increasing number of outbreaks in U.S.
hospitals, various hospitals turned to Pall Corp. to utilize its expertise in
biological processes often used in developing solutions for ultrapure water
used in pharmaceutical manufacturing.

Pall was asked to provide filtration treatment and the
AquaSafe Water Filter was selected. The point-of-use filter was installed in
various hospitals to precent the spread of Legionella and other potentially
lethal pathogens found in the water systems of hospitals as well as other
health care provider sites. The filter provided an effective barrier from
waterborne microbial contamination ensuring the availability of high-purity
water for bathing, showering, food preparation, drinking, rinsing of medical
instruments and other hygiene measures in hospitals and medical institutions.

The disposable, sterilizing grade filter (0.2 mm membrane)
for faucets and showerheads reduces microbial contamination and is a barrier
against common contaminants such as Legionella, Pseudomonas, Aspergillus and
Cryptosporidium, found in hospital water supplies. It served as an easy-to-use
solution for both large and small volumes of point-of-use water.

These various hospitals all found the filter to be an
effective solution to the threat of Legionella. The filter continues to be used
as part of the routine standard of care in these hospitals wherever
immune-compromised patients are located.

About the author

Contributed by Pall Corp.