Amoebic Meningoencephalitis: What causes delay in treatment; types of the disease

Amoebic Meningoencephalitis has been the most significant cause of concern for people across Kerala this year, with repeated cases getting reported from various districts. However, many are concerned that a wide delay is reported in starting treatment for the disease. According to experts, it is largely due to the difficulty in distinguishing it from other forms of meningoencephalitis. Here's what we need to know about the types of the disease. 

Two types of Amoebic Meningoencephalitis
Amoebic meningoencephalitis is caused by amoebas found in stagnant water, soil, cesspools, freshwater lakes and rivers. The disease has two major forms. The first is Primary Amoebic Meningoencephalitis (PAM), caused by the amoeba Naegleria fowleri. This form invades and destroys brain cells, resulting in swelling and severe damage to brain tissue. The second is Granulomatous Amoebic Encephalitis (GAE), which is caused by a different species of amoeba.

Until 2022, all reported cases were linked to Naegleria fowleri. However, in 2023, two cases were traced to Acanthamoeba. By 2024, yet another species, Vermamoeba vermicularis, was confirmed as a cause. Health authorities, meanwhile,  have also identified other amoebas such as Balamuthia Mandrillaris and Sappinia as culprits in recent infections.

PAM X GAE
1)PAM usually affects children and youngsters, while GAE can affect people of all ages.
2) PAM is typically seen in warm climates, whereas GAE shows no seasonal variation.

3)Those affected by PAM may occasionally experience changes in taste or smell. In most cases, however, its symptoms cannot be distinguished from those of bacterial meningitis. For those with GAE, eye infections or skin lesions may appear before symptoms related to the nervous system develop.
4) In PAM patients, the condition becomes critical soon after the amoeba enters the body. GAE, on the other hand, progresses more slowly, taking days or even weeks to worsen.

Examination
Systems for confirming the presence of amoeba through microscopic examination are available in all major medical colleges.

Patients with suspected amoebic meningoencephalitis are assessed for any history of contact with water entering the nose. If such contact is confirmed, their cerebrospinal fluid is subjected to a rapid test.

PAM should be suspected in patients diagnosed with bacterial meningitis who show no response to antibiotics or whose health condition deteriorates rapidly, even if there is no reported history of water exposure.

Samples are immediately sent for the RPCR test for molecular and genomic diagnosis. This facility is currently available at the Institute of Advanced Virology and the Public Health Lab in Thiruvananthapuram.

Medication
For the treatment of Primary Amoebic Meningoencephalitis (PAM) and Granulomatous Amoebic Encephalitis (GAE), a combination of medicines is used. The key component in them is Miltefosine.
Precautions
1)Avoid swimming or diving in stagnant water. If entry into such water is unavoidable, use a nose plug or keep your head above the surface to prevent water from entering the nose.
2)Do not rupture soil at the bottom of water bodies that are not cleaned regularly.
3)Ensure swimming pools, water theme parks and spas are always kept clean and chlorinated.
4) For nasal washing or sinus cleansing, use only boiled, filtered or properly treated water. Avoid using direct tap water.

5)Keep sprinklers and hoses away from the nose.
6) Always drain and dry children’s pools after use. Before allowing children to bathe, let the water in household pipes or hoses run for a while to flush out stagnant water.
6) The common symptoms of this disease are fever, headache, nausea and vomiting etc.