Quartan fever is one of the four types of malaria which can be contracted by humans.[1]
Quartan fever | |
---|---|
P. malariae schizont in a thick blood smear | |
Specialty | Infectious disease |
Symptoms | Fever |
Duration | Fever in 72 hour intervals |
Causes | Plasmodium spread by mosquitos |
Diagnostic method | Blood tests |
Medication | Chloroquine |
It is specifically caused by the Plasmodium malariae species, one of the six species of the protozoan genus Plasmodium. Quartan fever is a form of malaria where an onset of fever occurs in an interval of three to four days, hence the name "quartan".[2] It is transmitted by bites of infected female mosquitoes of the genus Anopheles. Symptoms include fevers which range from approximately 40–41 °C (104–106 °F) and occur periodically in 72 hour intervals. Although cases of malaria have occurred throughout the world, quartan fever typically occurs in the subtropics. Quartan fever is considered to be a less severe form of malaria fever that can be cured by anti-malarial medication, and prevention methods can be taken in order to avoid infection.[3]
The female Anopheles mosquito is a vector which transmits quartan fever to people. Mature mosquitoes carry uninucleate sporozoites in their salivary glands; these sporozoites enter a human's bloodstream when mosquitoes puncture human flesh during feeding. Sporozoites attack and inhabit liver parenchymal cells, called hepatocytes, in order to develop further. Once the uninucleate sporozoites have matured, the sporozoites then develop into uninucleate merozoites. Uninucleated merozoites mature into an erythrocytic stage called schizonts which contain merozoites. The schizonts, an infected erythrocyte, then rupture to release these merozoites; leading to more infections in the red blood cells. Uninucleated merozoites can also mature into uninucleate gametocytes which can invade and infect other female Anopheles mosquitoes during feeding, thus spreading the disease onto a wider population of humans.[3]
Fevers in intervals of 72 hours distinguish quartan fever from other forms of malaria where fevers range in 48 hour intervals or fever spikes that occur sporadically.[3]
Early indications of quartan fever include having irritated spots, welts, hives and burning skin, however this is dependent on individual's tolerance to mosquito bites and may not be evident on some people. With the Anopheles malaria mosquitoes, the welts are most likely to not appear unless there are severe allergic reactions.[4]
The prepatent period is the time interval for when parasites infect a host and when they can be detected on a thick blood film. For quartan fever, P. malariae has a prepatent period ranging from 16 to 59 days. Specifically in the case of quartan fever, the rupturing of liver stage schizonts releases merozoites. This stage of the P. malariae life cycle is known as the "ring stages" and are the first stages which can be detected in human blood for diagnosis.[5]
Ways to minimise exposure to the Anopheles mosquito include: