Human Diseases - Malaria (Class - XII)

P. falciparum is the deadliest malaria-causing agent. It is responsible for 85% of malaria cases.

P. falciparum has the tendency to infect large proportion of RBC. Patients infected with P. falciparum species will exhibit ten times the number of parasites per cubic millimetre of blood than the patients infected with the other three malaria species.

The humans acquire malarial parasite in the form of sporozoites which are haploid cells.

The patients of sickle cell anemia are naturally resistant to malaria. It is probably by microRNAs entering the parasite and tampering with its genome according to the latest research OR it may be due to smaller numbers of P. falciparum being able to infect sickled cells due to their shapes and increased rates of phagocytosis of infected sickled cells.

Most of the malarial drugs like chloroquine, primaquine, etc. destroy the malarial parasites while they are living inside red blood cells.

Mating of the gametocytes takes place in the gut of mosquito. After mating, the resultant embryo embed themselves in the mosquito’s gut, where they mature after 9 to 14 days into oocysts.

The malarial parasite enters the gut of mosquito in the form of gametocyte. These will mate only when they enter the gut of another mosquito that bites the infected person.

The embryonic form of malarial parasite is known as ookinetes. These embed themselves in the mosquito’s gut, where they mature after 9 to 14 days into oocysts.

P. malariae has the longest erythrocytic cycle. It is of 72 hours.

The first resistant malarial parasite was resistant to chloroquine. It was reported in Thailand in 1957.

Hypnozoite is the dormant state of malarial parasite, latent hypnozoites may rest undetected in the liver for up to 30 years.

Liver is the first organ invaded by a malarial parasite. Malarial parasites enter human body as sporozoites and are carried to the liver where they mature into forms known as schizonts. Over the next one to two weeks, each schizont multiplies into thousands of other forms known as merozoites. The merozoites break out of the liver and re-enter the bloodstream.

The first malaria vaccine to be approved was RTS,S (brand name Mosquirix), which was a recombinant vaccine engineered to express P. falciparum proteins capable of stimulating antibody production against the parasite.

P. falciparum causes severe malaria and affects brain, liver and kidney.

Black water fever (BWF) is a severe clinical syndrome, characterised by intravascular hemolysis, hemoglobinuria (with passage of black urine), and acute renal failure caused by a variety of factors in patients with P. falciparum infestation.