Legionella bacteria can present a risk anywhere where water is used or stored. It is all to easy to think of Legionella risk only in terms of cooling towers, showers and spas - but Kepak, a food producer for brands such as Rustlers, found this week prosecutions can be brought for failing to assess, control and monitor the risk in other water systems too.

This particular outbreak seems to have focussed on pressure washers, presumably used for cleaning equipment or processing carcasses. Such systems can of course harbour bacteria, and generate aerosols when used.

However the implications are even greater than the £45,000 of fines and costs - as following the closure of the site for decontamination it has never reopened.

Your grandmother probably told you not to go out in the rain or you would “catch your death of cold”. It seems maybe she knew more than we give her credit for - whilst most scientists agree that you can’t catch a cold by going out in the rain - it seems that you might catch Legionnaires’ disease. Researchers in Japan (reported here by the US CDC) found that Legionella pneumophila bacteria (the cause of 90% of Legionnaires’ disease cases) is found in puddles on road surfaces, and can even be splashed back up and become aerosolised within vehicles. Worse still the most prevalent serogroup found was L. pneumophila sg1 - the serogroup widely accepted as being the most virulent - and most likely to cause infections in generally healthy individuals.

Research by the UK Health Protection Agency has already suggested the weather patterns can affect the number of cases of Legionnaires’ disease observed each year.

Avoiding infection with Legionnaires’ disease is difficult, as the bacteria are invisible to the naked eye - and so we all rely on those responsible for maintaining water systems doing their job right. The risk factors that make you more or less likely to get infected are well known (being male, over 50, smoking, underlying health problems etc) but it seems that even divine intervention won’t prevent you getting infected if you are unfortunate enough to be exposed to an aerosol containing the bacteria.

Cruise ships are an ideal breeding ground for all sorts of infections: they have a large number of people in a very enclosed space which means that with diseases that are passed from person to person outbeaks spread quickly. These problems can be compounded by poor water quality or even direct contamination of the water supply itself. The potential consequences are highlighted in this story at the BBC

Behind Legionella, Norovirus (or Norwalk virus) is the microbial infection we are asked most about detecting in relation to cruise ships. Viruses are generally very difficult to detect in the environment though, and so its not currently part of our development plans. We are of course interested in talking to people with the need for detecting such viruses or methods of detecting them that might be suitable for use in the field.