How dangerous are brain eating amoeba?

CNN's Elizabeth Cohen explains what you need to know about naegleria fowleri, more commonly known as brain-eating amoeba, found in warm fresh water.

[lordvoldemort]

Well this wouldn’t affect me, I have no brain

[VeryNotSober]

I had a bad habit of holding my nose whenever I go in the water. Welp, it isn’t a bad habit now.

[I_Am_SciCurious]

These videos on infectious diseases are my favorite on this channel. The one on plague was great. Many people have no idea it's still around.

[Noodles]

I just know people came here after seeing that one short where a guy throws a cement block in the water of an abandoned basement

[bigk]

Dear cnn thanks now I won't go swimming.

[Tommytwothumbs]

Isn't nature beautiful ! How such a simple life form can bring down a much more evolved complex one ..

[monicaford]

Nothing to joke about. The kids who have died frm this suffered greatly😟

[KontauriC]

Me: *cements my nose before going swimming*

[SaturnMonkey]

*Had a brain eating amoeba once poor fella died of hungry*

[lovely_layla_asmr]

Sometimes it’s good to be the friend who still pinches there nose 🙂

[TaylorWilmes]

Don't go swimming in fresh warm water😂 are you serious

[errebusaether]

You’ve got to the unluckiest person to ever get an brain eating amoeba that’s for certain.

[csm]

I already didn't like to go to water places other than regularly cleaned swimming pools. Now i will only go to hourly desinfected bathtubs.

[afrainafrain]

Guys it’s super rare just don’t get lake water or pond/river water up your nose and you will be fine that simple.

[BrighamYen]

I am concerned about the water treatment process here in Los Angeles. Although the surface water supply (i.e., from the northern Sierras, etc.) go through a more stringent process, the ground water supply only gets disinfected by chloramine. The surface water supply goes through a process that includes ozone treatment, filter, and UV light, as well as chloramine through the distribution system. HOWEVER, according to a peer reviewed study, nitrification can dilute the potency of chloramine in the water supply that could allow N. fowleri to exist more readily in biofilm in the pipes. Here is an excerpt:

"N. fowleri in drinking water treatment and distribution
systems can be managed using disinfectant concentrations
typically encountered in well-run plants although nitrification
and attendant low disinfectant residuals may pose a challenge for
some systems. The greatest challenge for N. fowleri control is in
premise plumbing systems where conditions are largely outside
the control of utilities, residuals might be low or nonexistent, and
where water temperatures could be high enough to support rapid
growth of the amoebae."

More details about nitrification's concerning effects:

"Although no studies have reported direct involvement of
nitrification in distribution systems and storage facilities on
growth of N. fowleri, nitrification deserves special scrutiny in
assessment and management of N. fowleri risks. In the United
States, increasing numbers of utilities are adopting chloramines
for secondary disinfection (Seidel et al, 2005) because it is more
persistent than free chlorine, it results in lower production of
disinfection byproducts than free chlorine (Seidel et al, 2005),
and chloramines penetrate biofilms more readily than free chlorine
(LeChevallier et al, 1988). Under certain water quality
conditions, many distribution systems using chloramines for
secondary disinfection experience nitrification—the widespread
growth of ammonia-oxidizing and other bacteria (Cunliffe,
1991). Nitrification results in accelerated decay of chloramines
(and loss of residual disinfecting capacity), increased biofilm
growth, and reduced capacity to inactivate microorganisms in
the biofilms and suspended in the water. These conditions are
conducive to propagation of N. fowleri because they result in
reduced disinfectant residual and increased populations of cells
that may be used as food. Nitrification is also believed to be
common in premise plumbing systems (Zhang & Edwards,
2009) and a potential contributing cause of amplification of N.
fowleri and increased human exposure...Of greatest importance
in managing N. fowleri is maintaining a disinfectant residual throughout the drinking water distribution system and in the plumbing of premises. The authors
suggest that a target continuous free chlorine residual of 0.2 mg/L
at the end of distribution is a reasonable target for Naegleria spp.
control. Because of remaining uncertainty about the ability of
secondary disinfectant to control N. fowleri in biofilms, tank
sediments, and other problematic parts of operational distribution
systems, utilities and regulators should use a more conservative
minimum level such as 0.5 mg/L when developing an N.
fowleri control strategy."

UV Light, which is being used in Los Angeles' water treatment plant to reduce ozonation is concerning because it takes a lot of UV light to inactivate N. fowleri, and I'm not sure our UV light treatment here is set that high?

"Sarkur and Gerba (2012) reported that UV inactivation of N.
fowleri required slightly higher doses (63 and 13 mWsec/cm2)
for a 2-log inactivation for cysts and trophozoites, respectively,
than the dose required for Cryptosporidium parvum oocysts (~
10mWsec/cm2). The authors postulate that unlike Cryptosporidium,
this may be due to the increased ability of Naegleria to
repair UV-damaged DNA because they are naturally exposed to
UV in the natural environment."

This is concerning that N. fowleri is almost always in the premise piping:

"Studies have documented the persistence and growth of N.
fowleri in biofilms under conditions typical of distribution systems
and premise plumbing. Biyela et al (2012) introduced laboratory-grown
isolates of N. fowleri into cast-iron and PVC pipe
loops and conducted microbiological analyses of weekly water
samples and of a biofilm material collected five months after the
inoculation of the pipe loops with N. fowleri. Feedwater in the
pipe loops was maintained at 25°C, and flow rate through the
loops was maintained at 0.304 m/s. Other water quality aspects
of the feedwater (chlorine residual, dissolved organic carbon, etc.)
are not described. The pipe loops had been run continuously for
six years prior to inoculation with N. fowleri and were reported
to have well-established biofilms. Nested PCR was used for N.
fowleri detection (presence/absence). N. fowleri was detected in
all water samples collected from the pipe loops, and both vegetative
organisms and cysts were detected in the biofilm samples. No
comparisons of PVC and iron pipe were possible because all
samples were positive for N. fowleri.

The studies of Biyela et al (2012) and Goudot et al (2012)
demonstrate that
• N. fowleri readily attach to and persist in biofilms;
• N. fowleri have the potential to undertake significant and
rapid growth in biofilms; and
• growth in biofilms appears to depend primarily on temperature,
availability of substrate, and competition with other freeliving
amoebae."

And I found this to be the most interesting part about N. fowleri!

Could depleting iron from the water be a treatment in the future?

"Samples that were negative for N. fowleri tended to contain ironand
manganese-oxidizing bacteria, suggesting that iron and manganese
limitation could suppress the growth or prevent the occurrence
of N. fowleri in some groundwaters. Support for this
hypothesis is provided by Newsome and Wilhelm (1983) who
found that iron-chelating agents in water inhibited the growth of
N. fowleri, and by Kyle and Noblet (1985) who observed the highest
N. fowleri densities along a vertical profile in a pond at a depth
where exogenous iron was readily available."

[AlisonAlisonAlison]

Well 2020 has it all- *the gift that keeps on giving*

[_.jaleyart]

this is exactly why Im so worried when I go near lakes! Once when I was fishing I got a cut on my finger, my dad told me to put my hand in the water (because it was bleeding)..OF COURSE I SAID NO! I DON'T WANT AN INFECTION! (thats not related to the video..but still)

[stanleybowman-hood]

Moral of the story: always season your pond to not die

[somanosanghirun]

No wonder my school swimming pool is so frickin cold

[Ralsei]

It’s a really really really rare disease, it could be up to 98% chance of death. You don’t have to worry about it because it is super rare.