The brain eating amoeba, and the simple thing that stops it
Every warm season, Karachi loses people to Naegleria fowleri, an amoeba that lives in warm, untreated water. The fear is real, but so is the protection. The first thing to understand is the one most people get wrong.
It is not about drinking your water
You cannot catch it by swallowing water. The amoeba only harms you if untreated water goes up your nose, during ablution, bathing, or nasal rinsing, from where it can reach the brain. That single fact changes what you need to protect.
What the record shows
How it reaches people
The amoeba thrives in warm, still, untreated freshwater. In Pakistani homes the risk is not the glass you drink, it is the water that goes up the nose during wudu, a shower, or nasal rinsing, especially in the summer heat before the monsoon, when water sits warm in underground and rooftop tanks.
Why Karachi, why summer
Warm water is what the amoeba needs. Through the hottest months, water stored in tanks and carried through pipes with little or no chlorine warms to exactly the range it favours, and Karachi records new cases almost every year, most in people who never went near a lake or a pool.
How to protect your home
The protection is simple, and it is the same public health advice Pakistani health officials give every summer: keep a chlorine guard in your stored water, and keep untreated water out of your nose.
- 1
Clean the tanks before summer
Empty and scrub the underground and overhead tanks before the heat sets in. Our guide shows you how.
- 2
Chlorinate the stored water
Keep a chlorine guard in the tank so the water stays protected as it warms and waits. Follow the amount on the pack.
- 3
Guard the nose
For ablution and nasal rinsing, use water that has been properly treated, or boiled and cooled, and do not force untreated water up the nose.
Chlorine works when the water is clear and the guard is kept up. It is far less effective in cloudy water, so cleaning the tank and keeping the water clear go hand in hand with chlorinating it.
Protect your family this summer
See the full picture of your household water, or find the right Aquatabs for your tank.
Where these figures come from
The facts on this page are drawn from the United States Centers for Disease Control and Prevention, the World Health Organization, the Sindh Health Department as reported in the national press, and peer reviewed studies of the Karachi cases. Dosing is not given here, always follow the pack.