Quartan

Quartan refers to a pattern of fever associated with malaria caused by the parasite Plasmodium malariae. Fevers occur in 72-hour cycles, resulting in a paroxysm every three days (approximately every three days), which gives the name quartan. This pattern distinguishes quartan malaria from tertian malaria, which has 48-hour cycles caused by P. vivax and P. ovale, and from the irregular fevers of P. falciparum.

Etiology and transmission: P. malariae is transmitted by Anopheles mosquitoes. The parasite is found in tropical and subtropical regions and is less common than P. falciparum and P. vivax. Infections may become chronic with low-grade parasitemia lasting years if not treated.

Clinical features and diagnosis: Paroxysms include fever, chills, and sweating, recurring every 72 hours. Anemia and splenomegaly can occur; nephrotic syndrome is a rare complication. Incubation period is typically 18–40 days. Diagnosis is by microscopy of thick and thin blood films showing characteristic parasite forms; rapid diagnostic tests are less reliable for P. malariae. PCR can confirm species in difficult cases.

Treatment and prognosis: Chloroquine is usually effective for P. malariae; alternatives include ACTs in areas with resistance or when malaria species is not clearly known. Unlike P. vivax and P. ovale, P. malariae does not form dormant liver stages, so primaquine is not needed for radical cure. With appropriate treatment, prognosis is good; relapse is less common than with P. vivax.

Epidemiology and history: Historically described in the 19th and 20th centuries, quartan malaria remains present in regions with malaria transmission but is relatively uncommon compared with other malaria species. Public health measures and vector control continue to reduce its incidence.