Thiruvananthapuram’s conundrum. Where did the brain-eating amoebae originate?

Even a fortnight after the death of Akhil, the Health Department has still not been able to identify the source of the suspected primary amoebic meningoencephalitis (PAM) infection that eight people in Thiruvananthapuram district had fallen prey to. The latest case (42-year-old S Ajikumar) was confirmed on August 8.

What connects seven of the eight infected are their links to a pond (Kavinkulam) in the Maruthamcode ward of Athiyannur panchayat near Neyyattinkara. All seven, including Akhil who died on July 23, had regularly taken baths in the moss-infested pond.

The water from the pond was promptly tested. But it tested negative for the brain-eating amoeba Naegleria fowleri. A sampling error was not ruled out; the first sample could have been taken only from the surface of the pond. Therefore, a decision to go for a repeat sample test was taken.

Since the amoebae are found in the muddy water bed, it was said that the bottom of the pond should be first disturbed to allow the amoebae to rise, and only then should the samples be collected.

Wellspring of infections
However, the second sample has not yet been taken. "Without the retest, how are we to know conclusively that the infection came from the pond," said Vishnu S, the Maruthamcode ward member. A temporary fence has been erected around the pond and is now out of bounds for the public.

Over 50 others in Maruthamcode and Poothamcode wards in Athiyannur who bathed in the pond till July 24, the day it was sealed off, are also under surveillance. (Seven of the eight infected belong to these two wards)

Health experts say the initial symptoms of PAM - fever, headache, nausea, stiff neck - break out between 5-10 days. None among the 50-odd under surveillance has reported any symptoms even after a fortnight. "There is a family of four, including a child and an old man, who regularly use the pond. They had splashed about in the pond even on the day Akhil died (July 23). None of them has shown any symptoms," Vishnu said.

Driver’s puzzle
For the seven infected, there is at least an unclean pond to suspect. The eighth patient who has been officially confirmed with PAM, a driver named V Nijith, belongs to Mannammoola in Peroorkada, some 30 kms from Athiyannur and within the city limits. He has not taken a swim or even gone near any pond in the last two months. The Health Department is clueless about the source of his infection.

Narcotic connection
Health Minister Veena George had revealed that it was a dangerous drug habit that had caused infection in all the seven from Athiyannur. It is said that they had the habit of aggressively sniffing the drug mixed in the water from the pond.

The father of one of the patients, Shyam alias Achu, was furious. He asked the health minister to first conduct a blood test on these youngsters and then conclude whether they had taken drugs. "I am certain my son has not taken drugs," he told Malayala Manorama.

The deceased Akhil's sister, too, opposed the minister's claim. "Medical College doctors had told me that the amoeba got into his brain through his ears while bathing. The doctors had also told me that those with severe head injuries were at high risk. Does the minister know that my brother had sustained a major head injury 10 years ago," she said.

However, a local health worker in Athiyannur told Onmanorama on the condition of anonymity that one of the infected youngsters had spilled the beans about their drug behaviour to the Medical College doctors. "There is a vacant house near the pond where they spend most of their time. They might have indulged in drug use but we are not sure. But one of them was heard telling his relatives that he would speak the truth about their drug habit to the doctors," the source said.
Driver Nijith, on the other hand, has no history of drug use.

Final confirmation awaited
On top of all this, the PCR (polymerase chain reaction) results of the samples taken from the body of the infected have still not arrived. As per protocol, treatment for PAM can begin after a preliminary confirmation. This is done by doing a wet mount of the cerebrospinal fluid taken from the suspected cases. Wet Mount is a laboratory procedure to observe highly mobile microorganisms.

Only the PCR results could conclusively say whether it is PAM. Only a PCR test can identify the type of amoeba involved, whether it is the suspected brain-eater Naegleria or relatively less dangerous Acanthamoebam Balmuthia Mandrillaris, Sappinia or Vermabia.

Even Akhil's PCR results have not arrived. It will take at least 35 days for the results to come. Akhil's is expected by the last week of August.