Babesia bovis
Encyclopedia
Babesia bovis is a single-celled protozoan parasite of cattle
which occasionally infects humans. It is a member of the phylum Apicomplexa
, which also includes the malaria
parasite. The disease it and other members of the genus Babesia
causes is a hemolytic anemia
known as Babesiosis
and colloquially called Texas Cattle Fever, Redwater or Piroplasmosis. It is transmitted by bites from infected larval ticks of the order Ixodida. It was eradicated from the United States by 1943, but is still present in Mexico and much of the world's tropics. The chief vector of Babesia species is the southern cattle fever tick Rhipicephalus microplus
(formerly Boophilus microplus).
In 2007 the sequencing
of its genome
was announced. Measuring 8.2 million base pairs, its genome is remarkably similar to the genome of Theileria parva
, the cause of East Coast fever
(Theileriosis) in cattle.
or a water buffalo
, releasing the parasites into the animal's bloodstream. The involvement of the larval stage of the ticks in the cycle is specific to B. bovis; other Babesia species only involve adult ticks. The parasites then invade individual red blood cells, multiplying and destroying the host cells until the animal is stricken with hemolytic anemia. Adult ticks which feed upon infected cattle are infected themselves, completing the cycle. In humans, infection is rare and usually only affects splenectomized
patients.
Cattle
Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...
which occasionally infects humans. It is a member of the phylum Apicomplexa
Apicomplexa
The Apicomplexa are a large group of protists, most of which possess a unique organelle called apicoplast and an apical complex structure involved in penetrating a host's cell. They are unicellular, spore-forming, and exclusively parasites of animals. Motile structures such as flagella or...
, which also includes the malaria
Malaria
Malaria is a mosquito-borne infectious disease of humans and other animals caused by eukaryotic protists of the genus Plasmodium. The disease results from the multiplication of Plasmodium parasites within red blood cells, causing symptoms that typically include fever and headache, in severe cases...
parasite. The disease it and other members of the genus Babesia
Babesia
Babesia is a protozoan parasite of the blood that causes a hemolytic disease known as Babesiosis. There are over 100 species of Babesia identified; however only a handful have been documented as pathogenic in humans....
causes is a hemolytic anemia
Hemolytic anemia
Hemolytic anemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells , either in the blood vessels or elsewhere in the human body . It has numerous possible causes, ranging from relatively harmless to life-threatening...
known as Babesiosis
Babesiosis
Babesiosis is a malaria-like parasitic disease caused by infection with Babesia, a genus of protozoal piroplasms. After trypanosomes, Babesia are thought to be the second most common blood parasites of mammals and they can have a major impact on health of domestic animals in areas without severe...
and colloquially called Texas Cattle Fever, Redwater or Piroplasmosis. It is transmitted by bites from infected larval ticks of the order Ixodida. It was eradicated from the United States by 1943, but is still present in Mexico and much of the world's tropics. The chief vector of Babesia species is the southern cattle fever tick Rhipicephalus microplus
Rhipicephalus microplus
Rhipicephalus microplus is an economically important tick that parasitises a variety of livestock species; it is known as the cattle tick or southern cattle tick. It has been recorded on "cattle, buffalo, horses, donkeys, goats, sheep, deer, pigs, dogs and some wild animals"...
(formerly Boophilus microplus).
In 2007 the sequencing
Full genome sequencing
Full genome sequencing , also known as whole genome sequencing , complete genome sequencing, or entire genome sequencing, is a laboratory process that determines the complete DNA sequence of an organism's genome at a single time...
of its genome
Genome
In modern molecular biology and genetics, the genome is the entirety of an organism's hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. The genome includes both the genes and the non-coding sequences of the DNA/RNA....
was announced. Measuring 8.2 million base pairs, its genome is remarkably similar to the genome of Theileria parva
Theileria parva
Theileria parva is a parasitic protozoan, named in honour of Arnold Theiler, that causes East Coast fever in cattle, a costly disease in Africa. The main vector for T. parva is the tick Rhipicephalus appendiculatus...
, the cause of East Coast fever
East Coast fever
-Introduction:East Coast fever is a disease of cattle, sheep and goats caused by the protozoan parasite Theileria parva. The term excludes diseases caused by other Theileria, such as tropical theileriosis , caused by T. annulata, and human theileriosis, caused by T...
(Theileriosis) in cattle.
Infection
Babesia bovis are transmitted from mother ticks to their eggs, and can remain resident in tick populations for up to four years without infecting a vertebrate host. More commonly, a larval tick feeds upon a domestic cow, an African buffaloAfrican Buffalo
The African buffalo, affalo, nyati, Mbogo or Cape buffalo is a large African bovine. It is not closely related to the slightly larger wild Asian water buffalo, but its ancestry remains unclear...
or a water buffalo
Water buffalo
The water buffalo is a domesticated bovid widely kept in Asia, Europe and South America.Water buffalo can also refer to:*Wild water buffalo , the wild ancestor of the domestic water buffalo...
, releasing the parasites into the animal's bloodstream. The involvement of the larval stage of the ticks in the cycle is specific to B. bovis; other Babesia species only involve adult ticks. The parasites then invade individual red blood cells, multiplying and destroying the host cells until the animal is stricken with hemolytic anemia. Adult ticks which feed upon infected cattle are infected themselves, completing the cycle. In humans, infection is rare and usually only affects splenectomized
Splenectomy
A splenectomy is a surgical procedure that partially or completely removes the spleen.-Indications:The spleen, similar in structure to a large lymph node, acts as a blood filter. Current knowledge of its purpose includes the removal of old red blood cells and platelets, and the detection and fight...
patients.