Legionella Pneumophilia

More information on LEGIONELLA and prophylaxis of water borne pathogens

Drinking water in many developed countries has stringently controlled standards. Therefore it is difficult to imagine that water for human use, delivered through taps and shower heads, could contain harmful pathogens.

However bacteria such as the Legionella Pneumophilia and Mycobacterium Avium (both 0,5 – 0,7 µm in size) occur naturally in surface water and are frequently found in shower plumbing. The bacteria can reproduce themselves to high levels in the slimy layer (bio-film), which forms on the inside of water pipes filled with stagnant or slow moving warm water.

Situations like that are found in the plumbing of large buildings as hospital, nursing homes, apartment buildings, hotels, sports centers, camping’s and vacation homes in warm climates, that are unoccupied part of the year.

Legionella bacteria are released from the bio-film into the water stream and reach users when taps or showers are opened. To cause an infection the contaminated water must be vaporized and inhaled, after which the bacteria can settle in the lungs, causing the so-called veterans disease, legionella fever or pneumonia symptoms related to the M. Avium bacteria.  This can happen easily if someone takes a shower or inhales contaminated water vapor over a kitchen sink.

The first reported outbreak dated from 1976. Army veterans assembled in a hotel in Philadelphia, which had been unused  for a while, acquired massively pneumonia. Investigation showed that the outbreak was due to the presence of certain bacteria in the water, which were called Legionella Pneumophilia, on the analogy of the first known outbreak amongst army veterans (legionnaires).

The higher the bacteria concentration in the inhaled water vapor, the more likely an infection will occur. It has been demonstrated that the risk of infection is much greater at lower levels for the elderly, smokers and people with compromised immune systems. The fever variant (or Pontiac fever) is the mildest form. Veterans disease on the other hand can deteriorate into a chronic affection of the lungs with a fatality rate of approx. 15%.

Legislation prescribes that there shall be no stagnant water in shower plumbing and  that disinfection with chemicals and/or hot  water of 80 °C and moreover regular flushing of the plumbing must be carried out.

Quite often structural adaptations appear to be impractical or impossible. Despite all measures taken it is extremely difficult to eradicate bio-film once established. As a result  the presence of the legionella bacteria persists. Recent scientific studies show that Legionella bacteria feed on dead organic material, which stimulates the multiplication of remaining colonies after disinfection cycles.

Filtration at the point of use is therefore an obvious solution, to prevent outbreaks. However as long as  regular testing shows that there is no sign of Legionella contamination, there is no need to go through the expense to filter the water prophylactically.

Prime Water’s focus is safe water at the point of use when needed. The PW shower handles can be retrofitted with a 0,15 µm membrane filter that stops all bacteria, including Legionella Pneumophilia, in case of need. It provides protection, even if the problem persists for several months.

H36 shower with disposable membrane filter

A comforting thought to all facility managers, who dare not to think of the consequences of closing down the showers in their facility. Prime Water provides the means to handle the problem professionally and keep the showers open.

Countless hospitals, hotels and other public buildings have meanwhile been equipped with the Prime Water Legionella Safe showers.

Legionella bacteria