Sinus Rinsing For Health or Religious Practice

Filter: Use a filter designed to remove common germs.

• The label should read “NSF 53” or “NSF 58” or contain the words “cyst removal” or “cyst reduction”. If these words are present it means the filter can remove Naegleria. See more information about reading filter labels.
• Filter labels that read “absolute pore size of 1 micron or smaller” are also effective at removing Naegleria.
• Some manufacturers of nasal rinsing devices recommend using 0.2 micron absolute pore size filters that will also remove many types of bacteria; these would also remove Naegleria. Follow the manufacturer recommendations if 0.2 micron absolute filters are recommended.

Disinfect: Learn how to disinfect your water to make it is safe from Naegleria.

If you are unable to use 1) boiled or 2) sterile/distilled or 3) filtered water, you can use chlorine bleach to treat the water using the following instructions. If the water being treated is cloudy or murky (turbid), those particles may protect Naegleria from being killed by the chlorine. Because of that, we recommend filtering cloudy water first to remove particles and then using a double dose of chlorine disinfectant. The protocol below for disinfection with bleach is intended only to be used for nasal rinsing and not to be used for routine or emergency drinking water disinfection. We have added an extra amount of bleach to this protocol for an additional safety factor that is higher than that used for treating drinking water. If you need to disinfect drinking water, please see Emergency Water Supply Preparation.

If the water is clear:

• Obtain a medicine dropper and add the number of drops shown in the table below of unscented liquid household chlorine bleach for the amount (one gallon or one quart/liter) of clear water to be disinfected. Use the % sodium hypochlorite shown on the label (either 4 to 5.9% or 6 to 8.25%).
  • Stir the mixture well.
  • Let it stand for 30 minutes or longer before you use it.
  • Store the disinfected water in clean, sanitized, covered containers.

If the water is cloudy, murky, colored, or very cold:

• Filter water through a clean cloth, paper towel, or coffee filter

OR

• Allow any sediment to settle to the bottom of your container, then carefully pour the clear water from the top into a clean container with as little disturbance of the sediment layer as possible.

THEN

• Obtain a medicine dropper and add the number of drops of unscented liquid household chlorine bleach shown in the table below for the amount (1 gallon or 1 quart/liter) of clear water to be disinfected. Use the % sodium hypochlorite shown on the label (either 4 to 5.9% or 6 to 8.25%).
• Stir the mixture well.
• Let it stand for 30 minutes or longer before you use it.
• Store the disinfected water in clean, sanitized, covered containers.

Disinfection of Water Used for Nasal Rinsing

If liquid bleach is not available for disinfection, solid chlorine tablets or powder may be used. Two common forms that may be available are chlorinated isocyanurates and calcium hypochlorite. See below for links that may be helpful in mixing disinfecting solutions using solid chlorine tablets or powder. Because there are so many different types and sizes of tablets available (containing different amounts of chlorine), you should follow the manufacturer’s instructions for disinfection.

• WHO. Calcium hypochlorite fact sheet.[PDF – 5 pages]

The inactivation data for Naegleria is limited ^1-6 but recent CT values (concentration of disinfectant [mg/l] X contact time [in minutes]) have been developed ⁵. Under laboratory conditions, chlorine at a concentration of 1 ppm (1 mg/L) added to 104.4°F (38°C) clear well water at a pH of 8.01 will reduce the number of viable and more resistant Naegleria fowleri cysts by 99.99% (4 logs) in 56 minutes (CT of 56) ⁴. The bleach disinfection protocol is based on using this CT of 56 and increasing the amount of bleach to give a 5-fold safety factor* for the lowest concentration in the range used in the table. This is added to account for the unknown quality, organic content, pH, and temperature of the water to be treated, which can reduce the amount and efficacy of the bleach available for disinfection. For visibly cloudy water, the amount of bleach to add has been doubled since particles and organic matter in the water will also react with the chlorine. The protocol below for disinfection with bleach is intended only to be used for nasal rinsing and not to be used for routine or emergency drinking water disinfection. As mentioned above, we have added an extra amount of bleach to this protocol as an additional safety factor that is higher than that used for treating drinking water. If you need to disinfect drinking water, see Emergency Water Supply Preparation.

Disinfection of Water Used for Nasal Rinsing*

*The dosage calculations are based on 20 drops per ml (50µl/drop) and 3.8 liters per gallon. The formula for the calculation is shown below. It calculates the dose needed to achieve a CT of 56 and then multiplies by the safety factor of five to account for other particles or organic material in the water that could use up the chlorine:

If Naegleria fowleri amebae are present in tap water, nasal rising with tap water likely increases the risk of transmission compared to drinking the water. In addition, the potential outcome is much more severe than illness caused by most other waterborne pathogens. As a result, a five-fold protective factor has been adopted in these calculations to increase safety.

References

1. Chang SL. Resistance of pathogenic Naegleria to some common physical and chemical agents.[PDF – 8 pages] Appl Environ Microbiol. 1978;35:368-75.
2. 3.Tiewcharoen S, Junnu V. Factors affecting the viability of pathogenic Naegleria species isolated from Thai patients. J Trop Med Parasitol. 1999;22:15-21.
3. De Jonckheere J, van de Voorde H. Differences in destruction of cysts of pathogenic and nonpathogenic Naegleria and Acanthamoeba by chlorine.[PDF – 4 pages] Appl Environ Microbiol. 1976;31:294-7. (1mg/l for an hour for cysts)
4. Cursons RT, Brown TJ, Keys EA. Effect of disinfectants on pathogenic free-living amoebae: in axenic conditions.[PDF – 5 pages] Appl Environ Microbiol. 1980;40:62-6.
5. Sarkar P, Gerba C. Inactivation of Naegleria fowleri by chlorine and ultraviolet light. J AWWA. 2012;104:51-2.
6. Robinson BS, Christy PE. Disinfection of water for control of amoebae. Water. 1984;September:21-4.