Awareness about infection caused by ‘brain-eating amoeba’ urged

Like many water-borne bacterial and viral diseases, Naegleria fowleri, an amoebic infection, has emerged as a health threat across Pakistan.

Though the infection is not highly prevalent but reporting of its recent cases in various areas of Pakistan, particularly Karachi, has necessitated the need for specific attention of the concerned authorities.

So far, there is no specific treatment available for Naegleria fowleri infection nor any vaccine is available to prevent it. Many health experts believe that the only way to avoid the deadly infection is preventive measures. It is believed that over 95 per cent of the confirmed cases of the infection have to face death despite treatment.

The amoeba that causes the infection is also called as ‘brain-eating amoeba’, named after the most common complication produced by this infection, primary amoebic meningoencephalitis (PAM), which is usually a fatal complication. This condition directly involves the spread of infection to the brain substance itself causing high mortality rate, said Assistant Professor of Microbiology Dr. Humaira Zafar while talking to ‘The News’ in connection with precautionary measures needed to avoid the infection.

She added that the presentations of infection after the entry of ameba into body through nasal cavity can range from changes in taste and smell, nausea, vomiting, headache, fever, and stiff neck. “In severe cases when disease progresses, confusion, hallucinations, lack of attention, and coordination in body movements can easily be manifested ultimately leading to seizures/fits and death within 14 days of the infection.”

She said that the case fatality rate of the infection is estimated at 98 per cent and the symptoms of the infection start about five days (range is from one to seven days) after exposure.

Dr. Humaira explained that Naegleria fowleri is a free-living amoeba and typically found in contaminated stagnant and contaminated water, such as ponds, lakes, rivers, and hot springs. It is also found in soil especially near the warm water discharges of industrial plants, and non-chlorinated or poorly chlorinated swimming pools. Rarely, it can appear in inadequately treated samples of home-based tap water that is not treated enough to be entirely potable, though this is not the usual method of contracting the illness unless the water is very deeply inhaled, usually deliberately, she said.

She further explained that the predisposing factors for the transformation of inactive to active form of Naegleria fowleri induces food deprivation, crowding, desiccation, accumulation of waste products, and cold temperatures. “The ideal temperature is the changing temperatures ranging from 25°C to 42°C.”

She said that no specific treatment options and vaccine is available for the infection while the prognosis for infected patients is also very poor. “More than 95% of infections are fatal despite treatment. Survivors may have residual neurological problems, such as seizure disorders.”

She said that the only way to reduce the spread of infection is avoiding contact with contaminated sources. This is only possible if access to safe and chlorinated water sources be ensured, she said.

Dr. Humaira said that apart from preventive measures, there needs adoption of proper diagnostic approaches by the examination of Brain Fluid (Cerebro spial fluid) culture and PCR studies are the mainstay of diagnostic approaches. She said that awareness among public should be created on the subject and patients of the infection should fully cooperate with the doctors on the subject of collection of brain fluid so that their management can be started soon.