Plasmodium ovale: Difference between revisions

Revision as of 15:24, 9 December 2024

File:Relative incidence of Plasmodium (malaria) species by country of origin for imported cases to non-endemic countries.png

File:Microphotograph of Plasmodium ovale microgametocyte in Giemsa-stained thin blood film, with Schüffner's dots and hemozoin pigment.png

File:Microphotographs of Plasmodium ovale in Giemsa-stained thin blood films.jpg

File:IEcycle.PNG

Plasmodium ovale

Plasmodium ovale is a protozoan parasite and one of the species of Plasmodium that cause malaria in humans. It is one of the less common causes of malaria, with the others being Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, and Plasmodium knowlesi.

Taxonomy and Classification

Plasmodium ovale belongs to the genus Plasmodium, which is part of the phylum Apicomplexa. This genus is known for its role in causing malaria, a disease transmitted by the bite of infected Anopheles mosquitoes. P. ovale is further divided into two subspecies: Plasmodium ovale curtisi and Plasmodium ovale wallikeri.

Life Cycle

The life cycle of Plasmodium ovale is similar to that of other Plasmodium species and involves two hosts: the human host and the mosquito vector.

In the Human Host

1. Sporozoite Stage: The infection begins when an infected Anopheles mosquito bites a human, injecting sporozoites into the bloodstream. 2. Liver Stage: The sporozoites travel to the liver, where they invade hepatocytes and develop into schizonts. This stage can last for about 9-14 days. 3. Blood Stage: Schizonts rupture, releasing merozoites into the bloodstream. These merozoites invade red blood cells, where they undergo asexual reproduction, leading to cycles of fever and chills characteristic of malaria. 4. Hypnozoite Stage: P. ovale can form dormant liver stages known as hypnozoites, which can reactivate and cause relapses weeks or months after the initial infection.

In the Mosquito Vector

1. Gametocyte Stage: Some merozoites develop into sexual forms called gametocytes, which are taken up by a mosquito during a blood meal. 2. Fertilization and Oocyst Formation: In the mosquito's gut, gametocytes fertilize to form zygotes, which develop into ookinetes and then oocysts. 3. Sporozoite Formation: Oocysts release sporozoites, which migrate to the mosquito's salivary glands, ready to infect a new human host.

Clinical Features

Plasmodium ovale malaria is generally less severe than that caused by P. falciparum. Symptoms include: - Fever - Chills - Headache - Muscle aches - Fatigue

The fever pattern in P. ovale malaria is typically tertian, meaning it recurs every 48 hours.

Diagnosis

Diagnosis of P. ovale infection is primarily through microscopic examination of blood smears, where the parasite can be identified by its characteristic oval-shaped infected red blood cells. Molecular methods such as PCR can also be used for more accurate identification.

Treatment

The treatment for P. ovale malaria includes:

Chloroquine: For the blood stage of the parasite.
Primaquine: To eliminate hypnozoites in the liver and prevent relapses.

Epidemiology

Plasmodium ovale is primarily found in sub-Saharan Africa, but cases have also been reported in Southeast Asia and the Western Pacific. It is less prevalent than P. falciparum and P. vivax.

Prevention

Preventive measures include: - Use of insecticide-treated bed nets. - Indoor residual spraying. - Prophylactic antimalarial drugs for travelers to endemic areas.

Also see

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-[[file:Plasmodium_ovale_01.png|thumb|Plasmodium ovale 01]] [[file:Relative_incidence_of_Plasmodium_(malaria)_species_by_country_of_origin_for_imported_cases_to_non-endemic_countries.png|thumb|Relative incidence of Plasmodium (malaria) species by country of origin for imported cases to non-endemic countries|left]] [[file:Microphotograph_of_Plasmodium_ovale_microgametocyte_in_Giemsa-stained_thin_blood_film,_with_Schüffner's_dots_and_hemozoin_pigment.png|thumb|Microphotograph of Plasmodium ovale microgametocyte in Giemsa-stained thin blood film, with Schüffner's dots and hemozoin pigment]] [[file:Microphotographs_of_Plasmodium_ovale_in_Giemsa-stained_thin_blood_films.jpg|thumb|Microphotographs of Plasmodium ovale in Giemsa-stained thin blood films|left]] [[file:IEcycle.PNG|thumb|IEcycle]] '''Plasmodium ovale''' is a protozoan parasite and one of the species of [[Plasmodium]] that cause [[malaria]] in humans. It is one of the five species of Plasmodium that commonly infect humans, the others being [[Plasmodium falciparum]], [[Plasmodium vivax]], [[Plasmodium malariae]], and [[Plasmodium knowlesi]]. Plasmodium ovale is less common compared to Plasmodium falciparum and Plasmodium vivax.
+[[File:Relative incidence of Plasmodium (malaria) species by country of origin for imported cases to non-endemic countries.png|thumb]] [[File:Microphotograph of Plasmodium ovale microgametocyte in Giemsa-stained thin blood film, with Schüffner's dots and hemozoin pigment.png|thumb]] [[File:Microphotographs of Plasmodium ovale in Giemsa-stained thin blood films.jpg|thumb]] [[File:IEcycle.PNG|thumb]] Plasmodium ovale
-== Life Cycle ==
+'''Plasmodium ovale''' is a protozoan parasite and one of the species of Plasmodium that cause malaria in humans. It is one of the less common causes of malaria, with the others being [[Plasmodium falciparum]], [[Plasmodium vivax]], [[Plasmodium malariae]], and [[Plasmodium knowlesi]].
-The life cycle of Plasmodium ovale involves two hosts: the [[Anopheles]] mosquito and humans. The cycle begins when an infected Anopheles mosquito bites a human, injecting sporozoites into the bloodstream. These sporozoites travel to the liver, where they infect liver cells and mature into schizonts. The schizonts then rupture, releasing merozoites into the bloodstream, which infect red blood cells. Inside the red blood cells, the parasites undergo asexual reproduction, leading to the formation of more merozoites. Some of these merozoites develop into gametocytes, which can be taken up by another mosquito during a blood meal, continuing the cycle.
-== Clinical Features ==
+==Taxonomy and Classification==
-Plasmodium ovale causes a form of malaria known as ovale malaria. The symptoms of ovale malaria are similar to those caused by other Plasmodium species and include fever, chills, headache, and muscle pain. The fever in ovale malaria typically follows a tertian pattern, occurring every 48 hours. Unlike Plasmodium falciparum, Plasmodium ovale infections are generally less severe and less likely to be fatal.
+Plasmodium ovale belongs to the genus [[Plasmodium]], which is part of the phylum [[Apicomplexa]]. This genus is known for its role in causing malaria, a disease transmitted by the bite of infected [[Anopheles]] mosquitoes. P. ovale is further divided into two subspecies: '''Plasmodium ovale curtisi''' and '''Plasmodium ovale wallikeri'''.
-== Diagnosis ==
+==Life Cycle==
-Diagnosis of Plasmodium ovale infection is typically made through microscopic examination of blood smears, where the characteristic oval-shaped infected red blood cells can be observed. Molecular methods such as [[polymerase chain reaction]] (PCR) can also be used for more accurate identification.
+The life cycle of Plasmodium ovale is similar to that of other Plasmodium species and involves two hosts: the human host and the mosquito vector.
-== Treatment ==
+===In the Human Host===
-The treatment for Plasmodium ovale malaria includes antimalarial drugs such as [[chloroquine]] and [[primaquine]]. Chloroquine is used to treat the blood stage of the infection, while primaquine is used to target the liver stage and prevent relapse.
+. '''Sporozoite Stage''': The infection begins when an infected Anopheles mosquito bites a human, injecting sporozoites into the bloodstream.
+. '''Liver Stage''': The sporozoites travel to the liver, where they invade hepatocytes and develop into schizonts. This stage can last for about 9-14 days.
+. '''Blood Stage''': Schizonts rupture, releasing merozoites into the bloodstream. These merozoites invade red blood cells, where they undergo asexual reproduction, leading to cycles of fever and chills characteristic of malaria.
+. '''Hypnozoite Stage''': P. ovale can form dormant liver stages known as hypnozoites, which can reactivate and cause relapses weeks or months after the initial infection.
-== Epidemiology ==
+===In the Mosquito Vector===
-Plasmodium ovale is primarily found in sub-Saharan Africa, but it can also be found in some parts of Asia and the Western Pacific. It is less prevalent than Plasmodium falciparum and Plasmodium vivax.
+. '''Gametocyte Stage''': Some merozoites develop into sexual forms called gametocytes, which are taken up by a mosquito during a blood meal.
+. '''Fertilization and Oocyst Formation''': In the mosquito's gut, gametocytes fertilize to form zygotes, which develop into ookinetes and then oocysts.
+. '''Sporozoite Formation''': Oocysts release sporozoites, which migrate to the mosquito's salivary glands, ready to infect a new human host.
-== Related Pages ==
+==Clinical Features==
+Plasmodium ovale malaria is generally less severe than that caused by P. falciparum. Symptoms include:
+- Fever
+- Chills
+- Headache
+- Muscle aches
+- Fatigue
+The fever pattern in P. ovale malaria is typically tertian, meaning it recurs every 48 hours.
+==Diagnosis==
+Diagnosis of P. ovale infection is primarily through microscopic examination of blood smears, where the parasite can be identified by its characteristic oval-shaped infected red blood cells. Molecular methods such as PCR can also be used for more accurate identification.
+==Treatment==
+The treatment for P. ovale malaria includes:
+* '''Chloroquine''': For the blood stage of the parasite.
+* '''Primaquine''': To eliminate hypnozoites in the liver and prevent relapses.
+==Epidemiology==
+Plasmodium ovale is primarily found in sub-Saharan Africa, but cases have also been reported in Southeast Asia and the Western Pacific. It is less prevalent than P. falciparum and P. vivax.
+==Prevention==
+Preventive measures include:
+- Use of insecticide-treated bed nets.
+- Indoor residual spraying.
+- Prophylactic antimalarial drugs for travelers to endemic areas.
+==Also see==
 * [[Malaria]]
 * [[Plasmodium falciparum]]
 * [[Plasmodium vivax]]
-* [[Plasmodium malariae]]
-* [[Plasmodium knowlesi]]
 * [[Anopheles]]
+* [[Antimalarial drugs]]
-== See Also ==
+{{Malaria}}
-* [[Protozoa]]
+{{Protozoa}}
-* [[Vector (epidemiology)]]
-* [[Infectious disease]]
-{{Taxobox
-| name = Plasmodium ovale
-| image =
-| image_caption =
-| domain = [[Eukaryota]]
-| unranked_regnum = [[SAR (Stramenopiles, Alveolates, Rhizaria)|SAR]]
-| unranked_superphylum = [[Alveolata]]
-| phylum = [[Apicomplexa]]
-| classis = [[Aconoidasida]]
-| ordo = [[Haemosporida]]
-| familia = [[Plasmodiidae]]
-| genus = [[Plasmodium]]
-| species = '''P. ovale'''
-| binomial = Plasmodium ovale
-}}
 [[Category:Plasmodium]]
 [[Category:Parasitic diseases]]
-[[Category:Infectious diseases]]
-[[Category:Protozoal diseases]]
 [[Category:Malaria]]
-{{medicine-stub}}