1. Malaria a brief introduction :
Plasmodium is the causative agent of Malaria. Four species of Malaria, P falciparum, P vivax, P ovale, and P malariae, are involved in causing diseases in humans. Other species of Plasmodium cause the disease in reptiles, birds, and other mammals. Malaria is spread to humans by biting female mosquitoes of the genus Anopheles.
There are approximately 200 million to 500 million new cases each year worldwide, and the disease is the direct cause of 1 million to 2.5 million deaths per year.
2. Clinical manifestation of Malaria:
The patient has fever, chills, sweating, weakness, headache, and other symptoms mimicking a “viral syndrome .”The severe case causes an abnormal level of consciousness, severe anemia, renal failure, and multisystem failure.
3. Five species of Malaria:
- Plasmodium falciparum – It is the most prevalent species in Sub-Sahara Africa. This species is most prevalent and life-threatening.
- Plasmodium vivax – This species is the second most prevalent. It’s found in Southeast Asia and Latin America.
- Plasmodium Ovale – This species, along with vivax species, have the complication of a dormant liver stage, which causes clinical symptoms after reactivation in the absence of the mosquito bite.
- Plasmodium malariae – This species represents only a tiny fraction of infection.
- Plasmodium knowlesi – These species infect primates. This leads to human Malaria, but the mode of transmission is unknown.
4. Avian Malaria in New Zealand:
Avian Malaria has 35 species prevalent in New Zealand. The climatic changes increase the malarial infection in different species of birds. This malarial species is threatening endemic avian species, such as endangered mohua, thought to be particularly susceptible.
5. New Genus of Malaria found in Kerala, India:
This species was detected in Kerala during the covid-19 pandemic. Kerala was the fifth most infected state in India. Plasmodium Ovale was a new genus in the soldier who returned from Sudan. Plasmodium Ovale causes tertian Malaria. However, this species is not in much danger.
6. Human factor and Malaria:
- Genetic Factor: People with Sickle cell anemia have protection against P.falciparum.
A person who is negative for the Duffy blood group has a red cell which shows resistance to P.vivax. - Acquired Immunity: Frequent bites of mosquitoes create Semi-immunity. In Africa, south of the Sahara, the transmission rate is high; this semi-immunity is passed from mother to child.
- Pregnancy and Malaria: The immunity against P.falciparum decreases when an immune woman becomes pregnant. Hence Malaria during pregnancy is harmful to the mother and the child.
- Behavioral Factors: Poor rural populations cannot afford housing and bed nets, and people from the less endemic area do not take proper measures. Human activities create a breeding ground for larval growth, agricultural harvesting, and other activities that increase malarial transmission.
6. Conclusion:
The species of Plasmodium cause malarial infection. Five species of Malaria are involved in spreading the infection to different species. But changing climatic conditions and transmission rate leads to new genera of malarial. They have life-threatening characteristics. There are many human factors involved that increase rate of malarial infection.
References:
- https://www.ncbi.nlm.nih.gov/books/NBK8584/
- https://www.cdc.gov/dpdx/malaria/index.html
- http://www.xinhuanet.com/english/2020-12/11/c_139582117.htm#:~:text=%22Plasmodium%20Ovale%2C%20a%20new%20genus,the%20district%20hospital%20in%20Kannur
- https://www.mmv.org/malaria-medicines/five-species
- Schoener ER, Banda M, Howe L, Castro IC, Alley MR. Avian Malaria in New Zealand. New Zealand veterinary journal. 2014 Jul 4;62(4):189-98.
- https://www.cdc.gov/malaria/about/biology/index.html#tabs-1-3
