Legionella Outbreak at Western North Carolina Fair Kills 4 Blamed on Hot Tubs

[Ahhsomeguy]

This could be a game changer for the industry having filled active hot tubs at shows.
Four People Have Died From A Legionnaires' Outbreak Linked To A Hot Tub Display At A State Fair

 

[JamesW]

What recommendations would you make to help prevent further such incidents?

 

[Ahhsomeguy]

Here is abundant information that will be helpful to all hot tub and swimming pool users.

https://www.cdc.gov/healthywater/pdf/swimming/resources/legionella-factsheet.pdf

1. How is Legionella spread in hot tubs?

Legionella is naturally found in water, especially warm water. Hot tubs (or spas) that are not cleaned and disinfected enough can become contaminated withLegionella. A person can get infected with Legionella when they breathe in steam or mist from a contaminated hot tub.
Legionella can also be found in cooling towers, plumbing systems, and decorative pools or fountains.
Legionella is not spread from one person to another.

1. Four Questions to ask Your Hot Tub Operator
   • What was the most recent health inspection score for the hot tub?
   • Are disinfectant and pH levels checked at least twice per day?
   • Are disinfectant and pH levels checked more often when the hot tub is being used by a lot of people?
   • Are the following maintenance activities performed regularly:
2. 
   
   • » Removal of the slime or biofilm layer by scrubbing and cleaning?
   • » Replacement of the hot tub water filter according to manufacturer’s recommendations?
   • » Replacement of hot tub water?

The Most Recent Legionnaires' Disease Outbreaks | HC Info

The above link shows a list of Legionella incidents so you can search for the ones for spas.

http://www.floridahealth.gov/diseas...se/_documents/gsi-legionella-update-final.pdf

The above talks about the bacteria being in amoeba and biofilm.

The following are papers on Legionella in biofilms:

Biofilms: The Stronghold of Legionella pneumophila

There is now evidence that some legionellosis outbreaks are correlated with the presence of biofilms.

Factors Mediating Environmental Biofilm Formation by Legionella pneumophila

L. pneumophila is able to survive and persist within multi-species biofilms that cover surfaces within water systems. Biofilm formation by L. pneumophila is advantageous for the pathogen as it leads to persistence, spread, resistance to treatments and an increase in virulence of this bacterium. Furthermore, Legionellosis outbreaks have been associated with the presence of L. pneumophilain biofilms, even after the extensive chemical and physical treatments. In the microbial consortium-containing L. pneumophila among other organisms, several factors either positively or negatively regulate the presence and persistence of L. pneumophila in this bacterial community. Biofilm-forming L. pneumophila is of a major importance to public health and have impact on the medical and industrial sectors. Indeed, prevention and removal protocols of L. pneumophila as well as diagnosis and hospitalization of patients infected with this bacteria cost governments billions of dollars.

 

[JamesW]

Thanks for keeping people aware of the issue.

 

[Rattus Suffocatus]

If you actually read that article it appears the fill water at the fair itself had legionella bacteria in it! I imagine it might be very difficult to prove that the hot tub vendors were in fault. It appears one vendor tested negative. But you are correct in that if I were a vendor I would be REALLY careful at these events.

 

[JamesW]

The vendors should have maintained a good fc level in the tub, which would have killed the bacteria.

 

[Ahhsomeguy]

Even if fill water had it, a properly sanitized hot tub would eliminate the threat.

 

[Rattus Suffocatus]

And in at least one of the cases, they did.

 

[JamesW]

And in at least one of the cases, they did.

They did what?

 

[Rattus Suffocatus]

Eliminated the threat. One of the spa companies tested clean. Says in the linked article.

I suspect if it really is determined to be the hot tub displays (which this and other newer articles actually put in doubt, I would now be leaning to blaming the water supply at the fair, and the ladies restroom).. then it's the other vendor... if the other vendor didn't put any sanitizer in because its "only a couple of days"... well, then there you are....

 

[Newdude]

From what I read it had to have direct contact with the people. The mix of people getting sick probably rules out the ladies room. The airborne evaporation and steam around the hot tubs would be more likely. I doubt many people felt the hot tub water.

 

[JamesW]

Testing after the fact doesn't necessarily mean that the problem didn't exist.

Someone could have poured in some chlorine at any time before the test.

 

[JamesW]

The mix of people getting sick probably rules out the ladies room.

Important note: The thing in the bathroom that looks like a water fountain is not a water fountain. Don't drink from it.

 

[Ahhsomeguy]

The hot tubs are a very high probability to be the culprit. Hers’s what happens at a fair. Hot shot salespeople from the manufacturer and dealers are brought in to sell tubs. Over 35% of hot tub sales occur at fairs, shows and parking lot bonanzas. These guys don’t want to whiff sanitizer all day and don’t want to scare potential buyers away so they let the levels get down low or even to zero FAC. Yes, people poke their hands and fingers in the water as they walk by. Contact with water does not make you sick. It is the breathing in of the water vapors and moisture surrounding the contaminated tub that can cause this to people with compromised immune systems. This is not a new phenomenon. This occurs frequently. 29 people were killed just walking by a contaminated hot tub at a flower show in the Netherlands in 1999. Google it! This happened! There have been many additional outbreaks since then but people just don’t see all those stories.

 

[dlleno]

in addition to the obvious solution that proper spa set-up ( with shock and sanitation) could have prevented this outbreak, there is a related and less-emphasized factor that gives one pause when considering the purchase of a demo spa that has been used in such a situation: they had to have underwent some non-zero amount of storage and transportation, in warm weather, both prior to and after the event! Given how aggressive biofilms can be, and how this very bacteria has been shown to find safe harbor within a protective layer of biofilm, one has to go beyond the traditional de-con procedure in situations like this, it seem to me ..

One of the references I have cited in my original "purge test" articles is an interesting article showing the plausibility of biofilm accumulation even in the presence of chlorine. the summary is quoted as saying, "Results showed that the biofilm was able to accumulate on coupons and in the filter systems of reactors treated with ... 1–3 mg/L free chlorine"

Without an aggressive purge process, I think there is evidence that even the commercially-recognized decon procedure might still leave some bad guys behind.

 

[Arizonarob]

@dlleno I just read through all 3 parts of your blog, what a well thought out and executed performance test of the products. Thanks for taking the time, money, and effort to do so. I have bookmarked your blog to pass on your findings to others.

 

[dlleno]

Thank you im really glad to see that my work has contributed something useful!