COVID-19 patients at increased risk from Legionella co-infections

History can tell us a lot, looking at this study, it was concluded that most deaths in the 1918-1919 influenza pandemic likely resulted directly from secondary bacterial pneumonia. The report states if severe pandemic influenza is largely a problem of viral-bacterial copathogenesis, pandemic planning needs to go beyond addressing the viral cause alone. 

Another report also claims there were two key lessons from the 1918 “Spanish flu”, 1957, 1968, and 2009 outbreaks: 

The first – similarly most fatalities were due to bacterial co-infections

Whilst Legionella co-infection indications relating to Covid-19 are limited, there is evidence that links the two. As highlighted before, a study into COVID-19 fatalities in China found that up to 50% also had bacterial co-infections, of which Legionella pneumophila is one. 

At the time of writing, considering the 255 million COVID-19 cases across the world to date and 5.1 million deaths (2% CFR), it could be assumed that as many as 2.5million people who died could also have been co-infected. Add to this, it is claimed up to 50% of intermittent cases of hospital-acquired pneumonia are caused by legionellae and these outbreaks can have higher fatality rates than community-acquired single cases (10% community CFR, up to 28% CFR in hospitals). 

Despite robust water management programs in hospitals the global 75.6 million admissions of COVID in-patients during 2020 and 2021 has provided a real challenge. These patients need to use the facilities and Legionnaire’s disease occurs after inhalation of Legionella-containing aerosols from shower heads and certain medical equipment (e.g., respiratory equipment) as an example. 

It is therefore suggested that patients with COVID-19 should also be screened for Legionella routinely; due to the symptoms of both infections being remarkably similar, and patient vulnerability.  

The second - the mortality rate and severity scores were higher after the pandemics

COVID-19 infections can predispose patients to Legionella co-infections therefore posing a serious mortality threat to high-risk COVID-19 patients after the peak(s) of the pandemic. 

We’re told COVID-19 is here to stay and so is Legionella. We can see from Legionella infection rates that, over the years, cases have increased dramatically in all corners of the world (>900% increase in the USA and > 500% increase across Europe since 2000). With these viral and bacterial pneumonia-causing infections co-habiting, the risk will remain significant and Legionella may well have increased health risk even after the pandemic impact subsides and covid remains endemic.  

 So, let’s take a closer look at some of the potential causes for the link and the environment risks as people get their much-needed care in hospitals:

1. A rapid increase in the number of patients with COVID-19 entering the hospital setting. 
2. The clinical focus on COVID-19 potentially causing under-diagnosis of Legionella pneumophila.
3. Building closures or reduced use causing less consumption and potential stagnation of water in building water systems. 
4. Rushed time to plan, specify, install, and commission changes to water systems to support COVID–19 care requirements. 
5. Interruption or disruption to routine water maintenance due to staff shortages (self-isolation, illness, family responsibilities). 
6. Conversion of public buildings including hotels and conference centres to healthcare facilities (e.g., as isolation or recovery facilities).  

Whilst understandably water systems may not appear to be at the top of the priority list during the on-going COVID-19 pandemic, it is critical for the health and safety of patients, staff, and visitors that water systems are managed properly.  

Lab-based methods of Legionella testing, such as the lab culture method, can take many weeks to provide conclusive results. During that time, Legionella bacteria will be multiplying, given ideal conditions, so the result of the lab test may not reflect real-time reality. Plus, waiting several weeks before acting will undoubtedly be putting more vulnerable COVID-19 patients at risk.  

By incorporating Hydrosense into your water management control plan, you can detect the most dangerous strain of Legionella in any water system in just 25 minutes, allowing faster remedial action and reducing on-going risk to patients.