''Plasmodium gallinaceum'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of the genus ''

Plasmodium ''Plasmodium'' is a genus of unicellular eukaryotes that are obligate parasites of vertebrates and insects. The life cycles of ''Plasmodium'' species involve development in a Hematophagy, blood-feeding insect host (biology), host which then inj ...

'' (subgenus '' Haemamoeba'') that causes

malaria Malaria is a Mosquito-borne disease, mosquito-borne infectious disease that affects vertebrates and ''Anopheles'' mosquitoes. Human malaria causes Signs and symptoms, symptoms that typically include fever, Fatigue (medical), fatigue, vomitin ...

poultry Poultry () are domesticated birds kept by humans for the purpose of harvesting animal products such as meat, Eggs as food, eggs or feathers. The practice of animal husbandry, raising poultry is known as poultry farming. These birds are most typ ...

Description

This species was described by Alexandre Joseph Emile Brumpt (1877–1951) a French professor of parasitology during a trip to

Ceylon Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, also known historically as Ceylon, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian subcontinent, ...

(now Sri Lanka).

Stages

Oocyst Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism ...

s must develop inside the

vector Vector most often refers to: * Euclidean vector, a quantity with a magnitude and a direction * Disease vector, an agent that carries and transmits an infectious pathogen into another living organism Vector may also refer to: Mathematics a ...

host. They are not transmissible if they enter an avian host they will not develop.

Sporozoite Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organis ...

s are the

transmission Transmission or transmit may refer to: Science and technology * Power transmission ** Electric power transmission ** Transmission (mechanical device), technology that allows controlled application of power *** Automatic transmission *** Manual tra ...

stage. If they enter an avian host they may infect.

Vectors

Aedes aegypti ''Aedes aegypti'' ( or from Greek 'hateful' and from Latin, meaning 'of Egypt'), sometimes called the Egyptian mosquito, dengue mosquito or yellow fever mosquito, is a mosquito that spreads diseases like dengue fever, yellow fever, malar ...

'' is a

. ''P. gallinaceum'' manipulates ''A. aegypti'' to increase its own chances of success. Koella ''et al.'', 2002 finds that

oocyst Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism ...

s in the gut increase the

volume Volume is a measure of regions in three-dimensional space. It is often quantified numerically using SI derived units (such as the cubic metre and litre) or by various imperial or US customary units (such as the gallon, quart, cubic inch) ...

of each

blood meal Blood meal is a dry, inert powder made from blood, used as a high-nitrogen organic fertilizer and a high protein animal feed. By weight, it is generally 12% nitrogen with trace amounts (≤1%) of phosphorus and potassium. It is one of the hig ...

. This lowers the chances of disgorgement of the parasites into the final host

chicken The chicken (''Gallus gallus domesticus'') is a domesticated subspecies of the red junglefowl (''Gallus gallus''), originally native to Southeast Asia. It was first domesticated around 8,000 years ago and is now one of the most common and w ...

(''Gallus gallus domesticus'') which is important because oocysts can't infect. This prolongs the average duration of oocyst residence in the vector, increasing their chance of successfully maturing to the

stage. On the other hand

sporozoite Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organis ...

s do the opposite: They decrease the volume of meals, increasing the number of meals taken, shortening the time they must continue to be in the vector, and increasing their chance of being successfully disgorged into a final host. Because this is the transmittable (infectious) stage that is desirable. This appears to generalize to ''P. gallinaceum'' and any combination of mosquito and avian.

Virulence factors

Circumsporozoite protein Circumsporozoite protein (CSP) is a secreted protein of the sporozoite stage of the malaria parasite (''Plasmodium'' sp.) and is the antigenic target of RTS,S and other malaria vaccines. The amino-acid sequence of CSP consists of an immunodomina ...

(CSP) is required for host invasion. Warburg ''et al.'', 1992 provides a

monoclonal antibody A monoclonal antibody (mAb, more rarely called moAb) is an antibody produced from a cell lineage made by cloning a unique white blood cell. All subsequent antibodies derived this way trace back to a unique parent cell. Monoclonal antibodie ...

against CSP and demonstrates efficacy. The complete inhibition of

colonization of ''Aedes aegypti''

salivary gland The salivary glands in many vertebrates including mammals are exocrine glands that produce saliva through a system of ducts. Humans have three paired major salivary glands ( parotid, submandibular, and sublingual), as well as hundreds of min ...

s they achieved could be due to the antibody itself blocking contact between the sporozoites and the gland surface, however the antibody's binding is inhibited by a particular CSP motif, suggesting antibody efficacy ''is'' due to its anti-CSP effect. This 15-

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although over 500 amino acids exist in nature, by far the most important are the 22 α-amino acids incorporated into proteins. Only these 22 a ...

motif is one found by the original Dame ''et al.'', 1984 discovery of CSP which contains the 5-length CSP Region I.

Pathology

Infection produces severe changes in

blood plasma Blood plasma is a light Amber (color), amber-colored liquid component of blood in which blood cells are absent, but which contains Blood protein, proteins and other constituents of whole blood in Suspension (chemistry), suspension. It makes up ...

composition. Williams 2005 finds large changes in

plasma protein Plasma proteins, sometimes referred to as blood proteins, are proteins present in blood plasma. They perform many different functions, including transport of hormones, vitamins and minerals in activity and functioning of the immune system. Other b ...

s at 8 days post infection. There is a reduction in

albumin Albumin is a family of globular proteins, the most common of which are the serum albumins. All of the proteins of the albumin family are water- soluble, moderately soluble in concentrated salt solutions, and experience heat denaturation. Alb ...

, α2-globulin, and

creatinine Creatinine (; ) is a breakdown product of creatine phosphate from muscle and protein metabolism. It is released at a constant rate by the body (depending on muscle mass). Biological relevance Serum creatinine (a blood measurement) is an impor ...

. Meanwhile, there is an increase in γ1-globulin, γ2-globulin, total plasma protein, and total plasma

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

. (The enzyme increase is due to an increase in

aspartate aminotransferase Aspartate transaminase (AST) or aspartate aminotransferase, also known as AspAT/ASAT/AAT or (serum) glutamic oxaloacetic transaminase (GOT, SGOT), is a pyridoxal phosphate (PLP)-dependent transaminase enzyme () that was first described by Arthur ...

glutamate dehydrogenase Glutamate dehydrogenase (GLDH, GDH) is an enzyme observed in both prokaryotes and eukaryotic mitochondria. The aforementioned reaction also yields ammonia, which in eukaryotes is canonically processed as a substrate in the urea cycle. Typic ...

, and γ-glutamyltransferase.)

Description

Stages

Vectors

Virulence factors

Pathology

References

Further reading