Ten people who were under treatment for amoebic meningoencephalitis were discharged from Medical College, Thiruvananthapuram, on Thursday. Those who were diagnosed with the disease had been in contact with contaminated water, which had the presence of free-living amoebae, according to a release issued by the Health department here on Thursday.

Steps have been taken to do a case control study to determine the reason why only some people who used the same water source contracted the disease. The study will be conducted by the ICMR-National Institute of Epidemiology. Fatality rate of amoebic meningoencephalitis is 97 per cent.

In the first reported case of amoebic meningoencephalitis in the district, Akhil (27) from Kannaravila, Neyyattinkara, succumbed to the disease on July 23. Shortly after, five of his friends also tested positive and were admitted to the Medical College Hospital. All of them had bathed in a temple pond at Kannaravila.

A few days later, a man from Mannamoola in Peroorkada was also diagnosed with the disease. This man had not bathed in any public pond or water body, making the source of his infection a mystery. Cases which were not linked to this cluster were also confirmed from other parts of the district later. Till now, 14 people have been cured of this disease in Kerala.