KARACHI, Oct 11: While the Karachi Water and Sewerage Board is yet to adequately chlorinate its household water supply across the city as was resolved at a recent official meeting on the control of Naegleria fowleri, various town administrations launched awareness campaigns about the amoeba on Thursday.

According to official sources, the addition of chlorine to water for its purification could not be confirmed in over 15 per cent of the samples drawn from various pumping stations and localities in the city on Thursday.

There was no chlorine in 20 samples collected by a KWSB team from SITE, Landhi, Saddar, Malir, North Nazimabad, Gulshan-i-Iqbal, Jamshed, Lyari and Korangi towns.

On Oct 10, too, the KWSB had collected 79 samples, of which four did not have any chlorine parts, while traces of chlorine were found in 18 other samples. The quantity of chlorine ranged from 0.15 part per million to 0.25ppm in the remaining 43 samples and 0.5ppm in 14 other samples on Wednesday.

In all, 131 water samples were collected from all towns except Gulberg Town, where three of the 10 Naegleria deaths have occurred since May.

Traces were reported in 93 samples and absolute absence of chlorine was confirmed by laboratory in 20 samples, while chlorine ranged from 0.15ppm to 1ppm in 13 samples and from 0.5ppm to 2ppm in three samples drawn from pumping stations in Keamari Town and a swimming pool in Jamshed Town.

The high-level meeting held on Oct 8, also attended by the KWSB MD, had called for increasing the level of chlorination at the KWSB’s major treatment and pumping stations up to 2ppm and in a way that water did have not less than 0.5ppm when received at the users’ end.

According to a KWSB report, water samples with no chlorine are unsatisfactory, while having traces or any lab known parts of chlorine in it are held satisfactory.

The health EDO of Karachi, Dr Imdadullah Siddiqui, who is a member of the committee notified by the Sindh health department, among other terms, for overseeing the water sampling and maintenance of data, told Dawn that the overall rate of chlorination of water had increased in comparison to a couple of days back.

According to experts, chlorination is a water treatment that destroys disease-causing bacteria, nuisance bacteria, parasites and other organisms. Chlorination also removes soluble iron, manganese and hydrogen sulfide from water.

Liaquatabad Town administrator Syed Mohammad Taha said at an awareness session held for students and teachers at Sir Syed Girls College that Naegleria fowleri, also called the brain-eating amoeba, was found in warm freshwater, such as lakes and rivers. People should avoid activities in freshwater ways having no chlorination and ensure regular cleaning and chlorination of underground and overhead water tanks at least twice a year.

After an inspection water tanks at the college were also dewatered for proper cleaning.

Awareness walks and meetings were also held in Korangi Town, Sindh Government Hospital Korangi and Saudabad Government Hospital on Thursday.