Naegleria: Prevention is the best defence

Naegleria Fowleri, a parasitic protozoan, also commonly known as ‘the Brain-eater’, has snatched at least ten lives in Karachi since May this year.
The media have reported that 15 patients have been admitted to various hospitals in the city with symptoms of having contracted this parasite.
However, practitioners fear that there may have been other cases where the victims and their families did not report the cases and the symptoms went unnoticed and unlinked to the deadly parasite.
Before the recent outbreak in Pakistan, Naegleria emerged in 1965 in Australia. Around 144 patients have died from then in UK and the US.
Found worldwide in moist soil, fresh water ponds, lakes and swimming pools, Naegleria Fowleri is thermophilic (heat loving) and proliferates during the tropical and temperate climates. The usual source of acquiring the protozoan is diving in to pools and ponds.
However, among recent cases, some of the victims contracted the parasite after washing their noses using tap water.
The organism enters the body of its host via the nasal cavity and reaches the brain via olfactory nerves. As soon as it enters the brain, it initiates destroying the brain cells so quickly that death is certain within a couple of weeks, if no treatment is acquired.
The deadly organism forms a cyst to protect itself from the body’s immune system. The disease thus caused is termed as Primary Amoebic Meningoencephalitis (PAM) and is usually difficult to diagnose because of its mild symptoms such as Headache, nausea, vomiting, fever, lethargy, increase somnolence, seizures, stiff-neck, etc., which highly resemble bacterial or viral meningitis. However, the infection can be diagnosed by examining the spinal cord under the microscope. Newer methods using Polymerase Chain Reaction (PCR) are also being developed which could facilitate early detection.
The presence of N. fowleri amoebae in Karachi municipal water supply may have several elucidations. First, Karachi is devoid of an indigenous water source and water obtained from the two suburban freshwater lakes is not adequately filtered or chlorinated. Moreover, common leaks in water and sewage pipes can cause outflow of sewage into the water supply, which may be a potential reservoir for the amoebae. Given the rapidity with which the parasite takes its toll, precaution is perhaps the best mode of defense against it. Experts propose that boiled, sterilized or filtered water should be used, especially when brushing teeth, gargling, or cleaning the nasal area during ablution.
Moreover, swimming in the unregulated pools or puddles of rain water should be avoided. The government should also consider launching an awareness campaign that advises people to take necessary precautions without inciting undue panic among the public.