P Ovale Malaria | 12 Dec 2020

Why in News

Recently a not very common type of malaria, Plasmodium ovale, has been identified in a jawan in Kerala.

• The soldier is believed to have contracted it in Sudan, where Plasmodium ovale is endemic.

Key Points

• About:
  
  • Plasmodium ovale is one among the five kinds of malarial parasites — Plasmodium falciparum, Plasmodium vivax (the commonest ones), Plasmodium Malariae, Plasmodium Ovale and Plasmodium Knowlesi.
  • It is termed ovale as about 20% of the parasitised cells are oval in shape.
  • The parasite can remain in the spleen or liver of the body for a long time, even years, after the mosquito bite, and the person could become symptomatic later.
• Symptoms:
  
  • Symptoms include fever for 48 hours, headache and nausea, and it rarely causes severe illness.
• Similar to P vivax:
  
  • P ovale is very similar to P vivax and the treatment modality is the same as it is for a person infected with P vivax.
  • Distinguishing between P vivax and P ovale may be tricky and can be differentiated only through careful detection.
• Prevalence:
  
  • P ovale malaria is endemic to tropical Western Africa. It is relatively unusual outside of Africa and, where found, comprises less than 1% of the isolates.
  • It has also been detected in the Philippines, Indonesia and Papua New Guinea, but is still relatively rare in these areas.
• Transmission in India:
  
  • According to the National Institute of Malaria Research (NIMR), the Kerala case could be an isolated one and there are no recorded cases of local transmission so far.
  • Previously, too, isolated cases were reported in Gujarat, Kolkata, Odisha and Delhi. However, no local transmission has been recorded — which means these cases have been acquired.
  • In India, out of 1.57 lakh malaria cases in the high-burden states of Odisha, Chhattisgarh, Jharkhand, Meghalaya and Madhya Pradesh in 2019, 1.1 lakh cases (70%) were cases of falciparum malaria.
  • According to the recent World Malaria Report 2020, cases in India dropped from about 20 million in 2000 to about 5.6 million in 2019.

Malaria

• Malaria is caused by Plasmodium (a protozoan).
• Malaria caused by Plasmodium falciparum is the most serious one and can even be fatal.
• Life Cycle of Plasmodium:
  
  • Plasmodium enters the human body as sporozoites (infectious form) through the bite of infected female Anopheles mosquito.
  • The parasites initially multiply within the liver cells and then attack the Red Blood Cells (RBCs) resulting in their rupture.
    
    • The rupture of RBCs is associated with release of a toxic substance, haemozoin, which is responsible for the chill and high fever recurring every three to four days.
  • When a female Anopheles mosquito bites an infected person, these parasites enter the mosquito’s body and undergo further development.
  • The parasites multiply within them to form sporozoites that are stored in their salivary glands. When these mosquitoes bite a human, the sporozoites are introduced into his/ her body, thereby initiating the events mentioned above.

Source: IE