Article source: Herald Scotland
A RECENT WARNING that a Kilmarnock hospital where a series of baby deaths is being investigated must urgently upgrade its pipework or risk Legionnaires’ disease is a stark warning of this potentially fatal illness.
Legionnaires’ disease, caused by legionella bacteria, is a form of pneumonia. The recent scare at University Hospital Crosshouse (“Warning over ‘life-threatening’ Legionella outbreak at baby deaths hospital”, The Herald, June 27) and the recommendation that all water pipework must be replaced within five years brings this deadly pathogen into the news yet again.
If it seems that this disease’s frequency in headlines is increasing, that is not surprising. The US Centers for Disease Control has noted a 450 per cent increase in cases from 2000 to 2014, and European Centre for Disease Prevention and Control reported 2015 as having the highest number of cases ever recorded in Europe.
The Legionella bug that causes Legionnaires’ disease is found in all natural water sources, but becomes a danger when it starts to breed in industrial and domestic water systems.
It is a parasite of amoebae which grows in slime called biofilm which lines all man-made water systems. It can burst through the cell walls and escape into the water system. Humans can become infected when water splashes or sprays of any kind form droplets that contain the bug. These droplets are readily inhaled and cause Legionnaires’ disease when the bug enters lung cells, particularly in those over 50, smokers and heavy drinkers or anyone with an underlying medical condition or compromised immune system.
Because the Legionella bug is so ubiquitous, complete eradication is practically impossible, therefore strong control measures and checks are required.
Lab culture tests were the first test developed to identify and monitor the bacteria and they remain widely specified in regulations. However, lab culture tests have serious constraints, not least that the test takes 10-14 days to provide a result. It also does not detect the bug when it is in the most dangerous and active phase of its lifecycle. Clearly, there is risk that cannot be appropriately managed by lab tests alone given the two-week gap in finding a source.
For these reasons rapid testing based on the detection of DNA or antigen have been developed. The simplest of these to undertake, with the most rapid results is the antigen test, a technology pioneered by Scottish environmental technology company Albagaia. Similar to a pregnancy test, it allows a water sample to be added and within 25 minutes a red line will appear if the result is positive. This allows immediate action to be taken if Legionella is present.
Because current regulation focuses on lab testing, many Legionella risk management programmes have that as their focus. Yet people are exposed to risk each time these tests are undertaken because of the delay of up to two weeks for a result, and the fact the most dangerous phase of the deadly bug is ignored. In order to effectively protect the public, regulation and risk management programmes need to incorporate the latest rapid testing technologies.