Dealing with the unforeseen challenges caused by the COVID-19 pandemic has taken a significant toll on people all across the world. Many of the buildings where we lived out our pre-virus days have been largely empty and idle.
But as restrictions are easing in many parts and people are tiptoeing back into everyday life, they may face a new danger hidden within their building: water contaminated with the Legionella bacteria that cause Legionnaires’ disease — a serious type of pneumonia.
In this blog, we try to compare Legionnaires’ Disease with COVID-19 as they both share similar early symptoms.
It should, however, be noted that this blog is a hypothesis. It takes information from various sources and uses this to highlight areas where similarities can be noted.
What is Legionnaires Disease?
Legionnaires’ disease is a severe form of pneumonia — lung inflammation usually caused by infection. It’s caused by a bacterium known as legionella pneumophila.
Legionella bacteria are found naturally in freshwater environments, like lakes and streams. The bacteria can become a health concern when they grow and spread in human-made building water systems like:
- Showerheads and sink faucets
- Cooling towers (structures that contain water and a fan as part of centralized air cooling systems for buildings or industrial processes)
- Hot tubs
- Decorative fountains and water features
- Hot water tanks and heaters
- Large, complex plumbing systems
What is COVID-19?
Coronavirus disease (COVID-19) is an infectious disease caused by the SARS-CoV-2 virus.
COVID-19 can be severe and has caused millions of deaths around the world as well as lasting health problems in some who have survived the illness. The virus can lead to pneumonia, respiratory failure, heart problems, liver problems, septic shock, and death.
Researchers aren’t sure what caused it and investigations as to its origin are ongoing. There’s more than one type of coronavirus and most of them have originated from animals including bats, camels, cats, and cattle.
Unlike the flu, a lot of people aren’t immune to the coronavirus because it’s so new.
Comparing the Signs & Symptoms
Legionnaires’ disease usually develops 2 to 10 days after exposure to legionella pneumophila.
Symptoms include headaches, muscle aches, fatigue, cough, high temperature, chest pain, shortness of breath, and other flu-like symptoms.
These symptoms are sure to make people think of COVID-19. But Legionnaires’ disease comes from bacteria. It’s not viral.
Similar to SARS-CoV-2, Legionella bacteria infect a person’s lungs and causes pneumonia and, sometimes, death.
A mild form of Legionnaires’ disease — known as Pontiac fever — can produce fever, chills, headache and muscle aches. Pontiac fever doesn’t infect your lungs, and symptoms usually clear within two to five days.
Contracting the Disease
After Legionella grows and multiplies in a building water system, water containing Legionella can spread in droplets small enough for people to breathe in. People can get Legionnaires’ disease or Pontiac fever when they breathe in small droplets of water in the air that contains the bacteria.
Less commonly, people can get sick by aspiration of drinking water containing Legionella.
On the other hand, SARS-CoV-2, the virus, mainly spreads from person to person.
Most of the time, it spreads when a sick person coughs or sneezes. They can spray aerosol droplets 6 feet away or even further. If you breathe them in or swallow them, the virus can get into your body.
COVID-19 is contagious, hence why we are told to socially distance ourselves from others.
People at increased risk of getting sick from both these diseases are:
- People 50 years or older
- People with chronic lung disease (like chronic obstructive pulmonary disease or emphysema)
- People with weak immune systems or who take drugs that weaken the immune system (like after a transplant operation or chemotherapy)
- People with underlying illnesses such as diabetes, kidney failure, or liver failure
Effect of Weather on Disease Incidence
There are good reasons to expect a respiratory virus to show seasonal variation.
Infections from influenza and respiratory syncytial virus are more common during winter in temperate areas of the world. The lower humidity aids the spread of virus aerosols and could make the virus more stable.
Links between COVID-19 cases and temperature are less certain.
Studies from Australia, Spain & Iran have reported no effect of temperature and COVID-19 transmission or deaths. However, higher temperatures are associated with a lower number of cases in Turkey, Mexico, Brazil, and the U.S
On the other hand, statistics show that summer is a peak time for Legionnaires’ disease infections.
While Legionella bacteria are ubiquitous in freshwater sources, an outbreak could occur when provided with favourable growth conditions.
Legionella grows and thrives in temperatures ranging from 20°C to 45°C. As the temperatures start to rise in summers, the incoming mains water may be in this danger zone. The increased use of air cooling systems during the summer months can also be a concern.
Legionnaires Disease and COVID-19 Lockdown
Legionella bacteria multiply in water systems where temperatures are between 20°C to 45°C and water is stagnant, and nutrients are available.
With buildings shut down or infrequently used during the COVID-19 pandemic, water is not circulating through plumbing systems and has become stagnant. As a result, disinfectants in the water dissipate, potentially allowing microorganisms, bacteria and pathogens to grow within plumbing systems.
As buildings and areas begin to open back up and social distancing is relaxed, the risk of these pathogens being released into the environment increases. Contaminated aerosols could be circulated by showers and possibly cooling units being switched on again as the load increases on the building after a period of disuse.
Furthermore, those who have recovered recently from COVID-19 are susceptible to contracting Legionnaires’ Disease due to compromised immune systems.
Such systems may have been out of use for a significant time and in most cases cannot simply be used straight away. The system may require recommissioning as if new (that is thorough flushing, cleaning and disinfection and/or controlled flushing of outlets such as taps, showers and toilets) before returning to use and reopening of the building.
Advice for Reopening your Building Safely
It is the legal duty of those in control of premises such as offices, shops, cafes, restaurants and public buildings to reduce the risks of exposure to legionella bacteria and to make sure their water supplies are safe.
From a legionella control perspective, the most important thing to remember is not to simply open buildings up again for immediate use. When recommissioning a building of any kind, it is wise to create a plan to help you do so.
Essential steps for managing the risks associated with legionella bacteria include:
If you need expert guidance on how to reopen your premises safely after lockdown, get in touch with our team of water hygiene consultants for a free consultation.
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