Legionella Risk Control: UK

Legionella Risk Control.co.uk is part of the Ames Group Ltd and based in Birmingham, UK. We have an expert team dedicated to legionella services and control and operate nationwide carrying out risk assessments, testing and consultations.

What is Legionella?

water samplingLegionella is a common bacteria found mostly in water systems which can cause a respiratory disease known as Legionellosis. Legionella can also cause Legionnaires’ disease which is far more common and is a type of atypical pneumonia. In some cases Legionnaires’ disease can be fatal and symptoms include muscle pain, fever, shortness of breath, coughing and headaches. In more serious cases the disease cause extreme nausea, vomiting and diarrhoea and around 10% of Legionnaires’ cases are fatal.

As diseases go, Legionnaires’ disease is relatively new. The first recorded outbreak was in 1976 in the United States, where 182 members of the American Legion convention held in Philadelphia contracted the disease. Later 29 member died and Legionnaires’ disease became a worldwide concern. After further investigation studies discovered the causative agent was an unknown strain of bacteria and they named Legionella in homage to the American Legion convention. The particular strain that caused the outbreak was named Legionella pneumophila.

Between 1995 and 2005 a study was carried out that recorded over 32,000 cases of Legionnaires’ disease. The data was collected only in developed countries so the number of cases most probably were much higher. There are strict guidelines in place now and we are learning more about Legionella all the time. Improvements in diagnosis are continuing to improve and Legionella risk assessments and testing are now required by law.

How We Detect Legionella

Legionella and in particular Legionnaires’ disease is spread primarily by large scale water systems. It’s currently impossible to eliminate a risk of contamination altogether, but it is possible to reduce the risk. A Legionella risk assessment is required by law in commercial premises and this is in order to determine the risk of infection. Legionella can be detected by buffered charcoal yeast extract (BCYE) agar and this determines how much Legionella is in a system. To survive Legionella needs cysteine and iron and in the right conditions it can grow and thrive. One of the procedures for detecting Legionella in water filtration onto a charcoal yeast extract agar which contains antibiotics such as  glycine and cyclohexamide among others. This helps to suppress the natural flora in the sample and helps to detect the Legionella bacteria. Heat or acid can also be used to reduce interference from other microbes. On completion of the sample it is then held in incubation for up to 10 days until the presence of Legionella can be confirmed. Further techniques are them used to establish the exact species of bacteria and how much threat it contains.

A quick method of detection is favoured by hospitals and involves a urinary antigen test. This has the benefit of much quicker results and positive or negative results can be determined in just a few days. This is not a standard procedure for hospitals, but if Legionella pneumonia is suspected they can carry this test out to determine a diagnosis quicker. Technology and knowledge is increasing and new techniques are being discovered. In particular the use of a polymerase chain reaction can speed up detection and produce much faster results.

Legionella and Legionnaires’ Disease Prevention

Legionnaires DiseaseThe more we understand Legionella as a bacteria, the more we understand what is required to prevent it’s growth. By limited the conditions Legionella needs to thrive we can help reduce the chances of an outbreak of Legionnaires’ disease. A full Legionella risk assessment is required and then a plan is put in to place which businesses must adhere to, to prevent the disease being spread. Safety measures include:

  • Water temperature must be kept either above or below 20–50 °C (68–122 °F)
  • The removal of all pipes that have no outlet, to prevent standing water.
  • Eliminating construction materials that encourage the buildup of biofilm and other nutrients required for bacterial growth.
  • Regular disinfection of water systems and treatments such as chemical biocide or chlorination.
  • Implementing designs that reduce the production of aerosols.
  • An effective Legionella safety plan can include training, record-keeping, communication, contingency plans and management responsibilities.

Water systems are the main source of Legionella contamination, but this isn’t restricted to just hotels and office blocks. Cooling towers in particular can help spread the bacteria through the air, especially heat rejection equipment used in air conditioning. Legionella can reside in all types of water given the right conditions and of particular concern are:

  • Cooling towers
  • Swimming pools
  • Domestic water systems and showers
  • Ice-making machines
  • Refrigerators and refrigerated cabinets
  • Whirlpool spas
  • Hot springs
  • Fountains
  • Dental equipment
  • Soil
  • Automobile windshield washer fluid

Treatments For Legionnaires’ Disease

In the event of an outbreak of Legionnaires’ disease there are treatments available. Most commonly used are antibiotices that actively kill the Legionella bacteria. These include macrolides, tetracyclines, ketolides, and quinolones. Antibiotics penetrate the cells and kill the bacteria and in most cases are effective. Modern medicine and knowledge has helped decrease the mortality rate, mainly due to a better understanding of the antibiotics that fight Legionella. If treatment is started quickly then the mortality rate can be below 5%. It’s imperitive that the diagnosis is swift and the correct antibiotics prescribed to reduce the rate of severe illness and death.

Symptoms of Legionnaires’ Disease

It’s important for anyone working or living in an environment that could be exposed to Legionella to understand the common symptoms. Quick diagnosis is vital the prevent severe illness of death due to a Legionnaires’ Disease infection. Symptoms usually occur between 2 to 10 days after exposure to the Legionella bacteria, but in some caes can be seen up to 20 days later. Common symptoms include:

  • Fever
  • Chills
  • Coughing

Around one third of suffers experience coughing up blood and most have muscle pains, headaches, tiredness, loss of coordination and loss of appetite.
Persons with Pontiac fever experience fever and muscle aches without pneumonia. They generally recover in two to five days without treatment. For Pontiac fever the time between exposure and symptoms is generally a few hours to two days. Other symptoms include vomiting and severe impairment to cognitive ability.

How Ames Group Ltd Can Help

Ames Group Ltd have a team of Legionella assessors operating nationwide in the UK and we conduct testing and risk assessments to businesses throughout the country.  Contact us today if you have any questions or would like to book a consultation with a Legionella expert in your area.