View source for Babesiosis

{{Short description|Malaria-like parasitic disease caused by infection with the alveoate Babesia or Theileria}}
{{redirect|Texas fever}}
{{cs1 config |name-list-style=vanc |display-authors=6}}
{{Infobox medical condition (new)
| width           = 200px
| name            = Babesiosis
| synonyms        = Babesiasis, Texas fever
| pronounce       = Babesiosis {{IPAc-en|b|@|b|i:|z|ᵻ|'|ou|s|ᵻ|s}}, babesiasis {{IPAc-en|b|ae|b|ᵻ|'|z|ai|@|s|ᵻ|s}}
| symptoms        = [[fever]], [[chills]], headache, fatigue<ref name=CDCBabesiosis>{{cite web |url= https://www.cdc.gov/parasites/babesiosis/ |title= CDC — Babesiosis |publisher= [[Centers for Disease Control and Prevention]] |access-date= 2021-02-25 |archive-date= 2021-03-08 |archive-url= https://web.archive.org/web/20210308103409/https://www.cdc.gov/parasites/babesiosis/ |url-status= live }}</ref>
| risks           = Removed [[spleen]], weakened immune system, doing outdoor activities<ref name=CDCBabesiosis/>
| image = Blood smear of Babesia microti, annotated.png
| caption = [[Blood smear]] of ''[[Babesia microti]]''
| field           = [[Infectious disease (medical specialty)|Infectious disease]]
| differential diagnosis           = [[Malaria]]
}}

'''Babesiosis''' or  '''piroplasmosis''' is a [[malaria]]-like [[parasitic disease]] caused by infection with a [[eukaryotic]] parasite in the order [[Piroplasmida]], typically a ''[[Babesia]]'' or ''[[Theileria]]'', in the [[phylum]] [[Apicomplexa]].<ref>{{cite book |first1=Stephen A. |last1=Berger |first2=John S. |last2=Marr |title=Human Parasitic Diseases Sourcebook |url=https://books.google.com/books?id=AB39e6KZ8MMC |year=2006 |publisher=Jones & Bartlett Learning |isbn=978-0-7637-2962-2 |access-date=2016-10-14 |archive-date=2013-11-13 |archive-url=https://web.archive.org/web/20131113073942/http://books.google.com/books?id=AB39e6KZ8MMC |url-status=live }}</ref> Human babesiosis [[Tick-borne disease|transmission via tick bite]] is most common in the [[Northeastern United States|Northeastern]] and [[Midwestern United States]] and parts of Europe, and sporadic throughout the rest of the world. It occurs in warm weather.<ref>{{cite web|title = CDC — Babesiosis|url = https://www.cdc.gov/parasites/babesiosis/|website = www.cdc.gov|access-date = 2015-10-25|first = CDC - Centers for Disease Control and|last = Prevention|archive-date = 2015-10-25|archive-url = https://web.archive.org/web/20151025150642/http://www.cdc.gov/parasites/babesiosis/|url-status = live}}</ref>  People can get infected with ''Babesia'' parasites by the bite of an infected [[tick]], by getting a [[blood transfusion]] from an infected donor of blood products, or by congenital transmission (an infected mother to her baby).<ref>{{cite web|title = CDC2 - Babesiosis|url = https://www.cdc.gov/parasites/babesiosis/resources/babesiosis_policy_brief.pdf|website = www.cdc.gov|access-date = 2018-09-20|first = CDC - Centers for Disease Control and|last = Prevention|archive-date = 2018-07-27|archive-url = https://web.archive.org/web/20180727113507/https://www.cdc.gov/parasites/babesiosis/resources/babesiosis_policy_brief.pdf|url-status = live}}</ref>
Ticks transmit the human strain of babesiosis, so it often presents with other tick-borne illnesses such as [[Lyme disease]].<ref name="NEJM Babesiosis Review" /> After [[Trypanosoma|trypanosome]]s, ''Babesia'' is thought to be the second-most common blood [[parasite]] of mammals. It can have major adverse effects on the health of domestic animals in areas without severe winters. In cattle, the disease is known as '''Texas cattle fever''' or '''redwater'''.<ref name="Hunfeld">{{cite journal |vauthors=Hunfeld KP, Hildebrandt A, Gray JS |title=Babesiosis: Recent insights into an ancient disease |journal=Int J Parasitol |volume=38 |issue=11 |pages=1219–37 |year=2008 |doi=10.1016/j.ijpara.2008.03.001 |pmid=18440005}}</ref>

== Signs and symptoms ==
Half of all children and a quarter of previously healthy adults with ''Babesia'' infection are asymptomatic. When people do develop symptoms, the most common are fever and [[hemolytic anemia]], symptoms that are similar to those of malaria.<ref name="NEJM Babesiosis Review" /> People with symptoms usually become ill 1 to 4 weeks after the bite, or 1 to 9 weeks after transfusion of contaminated blood products. A person infected with babesiosis gradually develops [[malaise]] and fatigue, followed by a fever. Hemolytic anemia, in which red blood cells are destroyed and removed from the blood, also develops. Chills, sweats, and [[thrombocytopenia]] are also common symptoms. Symptoms may last from several days to several months.<ref>{{cite journal |vauthors=Marcos LA, Wormser GP |title=Relapsing Babesiosis With Molecular Evidence of Resistance to Certain Antimicrobials Commonly Used to Treat Babesia microti Infections |journal=Open Forum Infect Dis |volume=10 |issue=8 |article-number=ofad391 |date=August 2023 |pmid=37539067 |pmc=10394720 |doi=10.1093/ofid/ofad391 }}</ref>

Less common symptoms and physical exam findings of mild-to-moderate babesiosis:<ref name="NEJM Babesiosis Review" />
{{columns-list|colwidth=30em|
* Headache
* [[Myalgia|Muscle pain]]
* [[Anorexia (symptom)|Anorexia]]
* Nonproductive cough (mucus is not coughed up)
* [[Arthralgias]] (noninflammatory joint pain, unlike arthritis, which is inflammatory)
* [[Nausea]]
* [[Vomiting]]
* [[Sore throat]]
* Abdominal pain
* [[Conjunctival injection|Pink eye/Conjunctivitis]]
* [[Photophobia]] (abnormal intolerance to visual perception of light)
* Weight loss
* [[Emotional lability]]
* [[Depression (mood)|Depression]]
* [[Hyperesthesia]] (more sensitive to stimuli)
* [[Splenomegaly|Enlarged spleen]]
* Pharyngeal erythema
* [[Hepatomegaly|Enlarged liver]]
* [[Jaundice]] (yellowing of the skin and of the [[sclera]])
* Retinopathy with splinter hemorrhages
* Retinal infarcts
* [[Neutropenia]]<ref>{{cite journal|vauthors=Wormser GP, etal|title=Neutropenia in congenital and adult babesiosis|journal=Am J Clin Pathol|year=2015|volume=144|issue=1|pages=94–96|url=http://www.medscape.com/viewarticle/847995?nlid=86904_804&src=wnl_edit_medp_infd&uac=21973EZ&spon=3&impID=796573&faf=1|doi=10.1309/AJCP2PHH4HBVHZFS|pmid=26071466|doi-access=free|access-date=2015-08-19|archive-date=2019-12-18|archive-url=https://web.archive.org/web/20191218223616/http://www.medscape.com/viewarticle/847995?nlid=86904_804&src=wnl_edit_medp_infd&uac=21973EZ&spon=3&impID=796573&faf=1|url-status=live}}</ref>
}}
In more severe cases, symptoms similar to malaria occur, with fevers up to 40.5&nbsp;°C (105&nbsp;°F), shaking chills, and severe anemia (hemolytic anemia). Organ failure may follow, including [[adult respiratory distress syndrome]]. Sepsis in people who have had a [[splenectomy]] can occur rapidly, consistent with [[overwhelming post-splenectomy infection]]. Severe cases are also more likely to occur in the very young, very old, and persons with [[immunodeficiency]], such as [[HIV/AIDS]] patients.<ref>{{cite journal |vauthors=Lobo CA, Singh M, Rodriguez M |title=Human babesiosis: recent advances and future challenges |journal=Curr Opin Hematol |volume=27 |issue=6 |pages=399–405 |date=November 2020 |pmid=32889826 |pmc=11042670 |doi=10.1097/MOH.0000000000000606 }}</ref>

A reported increase in human babesiosis diagnoses in the 2000s is thought to be caused by more widespread testing and higher numbers of people with immunodeficiencies coming in contact with ticks, the disease vector.<ref name="Hunfeld"/> Little is known about the occurrence of ''Babesia'' species in malaria-[[Endemic (epidemiology)|endemic]] areas, where ''Babesia'' can easily be misdiagnosed as ''[[Plasmodium]]''. Human patients with repeat babesiosis infection may exhibit [[premunity]].<ref name="ShawDay2005">{{cite book|last1=Shaw|first1=Susan E.|last2=Day|first2=Michael J.|title=Arthropod-borne Infectious Diseases of the Dog and Cat|url=https://books.google.com/books?id=OwE4yoj3LukC&pg=PA71|date=11 April 2005|publisher=Manson Publishing|isbn=978-1-84076-578-6|page=71|access-date=14 October 2016|archive-date=26 June 2014|archive-url=https://web.archive.org/web/20140626180318/http://books.google.com/books?id=OwE4yoj3LukC&pg=PA71|url-status=live}}</ref>

==Cause==
''Babesia'' species are in the [[phylum]] [[Apicomplexa]], which also has the protozoan parasites that cause [[malaria]], [[toxoplasmosis]], and [[cryptosporidiosis]].<ref name="NEJM Babesiosis Review" /> Four clades of ''Babesia'' species infect humans. The main species in each clade are:{{cn|date=August 2022}}
# ''B. microti'' (< 3&nbsp;μm)
# ''B. <!-- duncani'' and ''B. --> duncani''
# ''B. divergens'' (cattle parasite seen mostly in Europe) and ''B.&nbsp;venatorum'' ([[roe deer]] parasite, formerly called EU1), most closely related to the large ''Babesia'' clade
# Large'' Babesia'' (> 3&nbsp;μm) mostly infects [[ungulates]], but also includes K01 strain (an isolated case observed in South Korea, see [[#Isolated cases|isolated cases]])

== Pathophysiology ==
[[Image:Babesia life cycle human en.svg|thumb|450px|''Babesia'' lifecycle]]
''Babesia'' parasites reproduce in [[red blood cell]]s, where they can be seen as plus-shaped inclusions (four [[merozoite]]s asexually budding, but attached forming a structure looking like a "[[Maltese cross]]")<ref name="Noskoviak2008">{{cite journal |vauthors=Noskoviak K, Broome E | title = Images in clinical medicine. Babesiosis | journal = N Engl J Med | volume = 358 | issue = 17 | pages = e19 | year = 2008 | pmid = 18434647 | doi =10.1056/NEJMicm070903 }}</ref> and cause hemolytic anemia, quite similar to malaria.

Unlike the ''Plasmodium'' parasites that cause malaria, ''Babesia'' species rarely exhibit an exoerythrocytic phase with trophozoite forms.<ref>{{cite journal |vauthors=Setty S, Khalil Z, Schori P, Azar M, Ferrieri P |title=Babesiosis. Two atypical cases from Minnesota and a review |journal=Am J Clin Pathol |volume=120 |issue=4 |pages=554–9 |date=October 2003 |pmid=14560566 |doi=10.1309/N3DP-9MFP-NUJD-4XJY }}</ref>

In nonhuman animals, ''[[Babesia canis]] rossi'', ''[[Babesia bigemina]]'', and ''[[Babesia bovis]]'' cause particularly severe forms of the disease, including severe haemolytic anaemia, with positive erythrocyte-in-saline-agglutination test indicating an immune-mediated component to the haemolysis. Common sequelae include haemoglobinuria "red-water", disseminated intravascular coagulation, and "cerebral babesiosis" caused by sludging of erythrocytes in cerebral capillaries.{{citation needed|date=June 2016}}

In bovine species, the organism causes hemolytic anemia, so an infected animal shows pale mucous membranes initially. As the levels of [[bilirubin]] (a byproduct of red blood cell lysis) continue to increase, the visible mucous membranes become yellow (icterus) due to the failure of the liver to metabolize the excess bilirubin.  Hemoglobinuria is seen due to the excretion of red-blood-cell lysis byproducts via the kidneys. A fever of 40.5&nbsp;°C (105&nbsp;°F) develops due to the release of inflammatory byproducts.{{citation needed|date=June 2016}}

== Diagnosis ==
Only specialized laboratories can adequately diagnose ''Babesia'' infection in humans, so ''Babesia'' infections are considered highly under-reported. It develops in patients who live in or travel to an endemic area or receive a contaminated [[blood transfusion]] within the preceding 9 weeks, so this aspect of the medical history is vital.<ref name="idsa-guidelines"/> Babesiosis may be suspected when a person with such an exposure history develops persistent fevers and hemolytic anemia. The definitive diagnostic test is the identification of parasites on a [[Giemsa stain|Giemsa-stained]] [[blood film|thin-film blood smear]].<ref name="idsa-guidelines">{{cite journal |vauthors=Wormser GP, Dattwyler RJ, Shapiro ED |title=The clinical assessment, treatment, and prevention of Lyme disease, human granulocytic anaplasmosis, and babesiosis: clinical practice guidelines by the Infectious Diseases Society of America |journal=Clin. Infect. Dis. |volume=43 |issue=9 |pages=1089–134 |date=November 2006 |pmid=17029130 |doi=10.1086/508667 |url=http://www.empirestatelymediseaseassociation.org/Scientific%20Articles/IDSA%20RESTRICTIVE%20GUIDELINES%202006.pdf |display-authors=etal |doi-access=free |access-date=2019-09-20 |archive-date=2020-07-26 |archive-url=https://web.archive.org/web/20200726120418/http://www.empirestatelymediseaseassociation.org/Scientific%20Articles/IDSA%20RESTRICTIVE%20GUIDELINES%202006.pdf |url-status=live }}</ref>

So-called "Maltese cross formations" on the blood film are diagnostic ([[pathognomonic]]) of babesiosis since they are not seen in malaria, the primary differential diagnosis.<ref name="Noskoviak2008"/> Careful examination of multiple [[smear test|smear]]s may be necessary, since ''Babesia'' may infect less than 1% of circulating red blood cells, thus be easily overlooked.<ref name="krause">{{cite journal |author=Krause PJ |title=Babesiosis diagnosis and treatment |journal=Vector Borne Zoonotic Dis. |volume=3 |issue=1 |pages=45–51 |year=2003 |pmid=12804380 |doi=10.1089/153036603765627451 }}</ref>

[[Serology|Serologic testing]] for [[antibody|antibodies]] against ''Babesia'' (both [[Immunoglobulin G|IgG]] and [[IgM]]) can detect low-level infection in cases with high clinical suspicion, but negative blood film examinations. Serology is also useful for differentiating babesiosis from malaria in cases where people are at risk for both infections. Since detectable antibody responses require about a week after infection to develop, serologic testing may be falsely negative early in the disease course.<ref>{{cite journal |vauthors=Krause PJ, Telford SR, Ryan R |title=Diagnosis of babesiosis: evaluation of a serologic test for the detection of ''Babesia microti'' antibody |journal=J. Infect. Dis. |volume=169 |issue=4 |pages=923–6 |date=April 1994 |pmid=8133112 |doi= 10.1093/infdis/169.4.923|display-authors=etal}}</ref>

A [[polymerase chain reaction]] (PCR) test has been developed for the detection of ''Babesia'' from the peripheral blood.<ref>{{cite journal |vauthors=Persing DH, Mathiesen D, Marshall WF |title=Detection of Babesia microti by polymerase chain reaction |journal=J. Clin. Microbiol. |volume=30 |issue=8 |pages=2097–103 |date=August 1992 |doi=10.1128/jcm.30.8.2097-2103.1992 |pmid=1500517 |pmc=265450 |url=|display-authors=etal}}</ref> PCR may be at least as [[sensitivity and specificity|sensitive and specific]] as blood-film examination in diagnosing babesiosis, though it is also significantly more expensive.<ref>{{cite journal |vauthors=Krause PJ, Telford S, Spielman A |title=Comparison of PCR with blood smear and inoculation of small animals for diagnosis of ''Babesia microti'' parasitemia |journal=J. Clin. Microbiol. |volume=34 |issue=11 |pages=2791–4 |date=November 1996 |doi=10.1128/jcm.34.11.2791-2794.1996 |pmid=8897184 |pmc=229405 |url=|display-authors=etal}}</ref> Most often, PCR testing is used in conjunction with blood film examination and possibly [[serology|serologic testing]].<ref name="idsa-guidelines"/>

Other laboratory findings include decreased numbers of red blood cells and [[platelets]] on [[complete blood count]].<ref>{{cite journal |vauthors=Akel T, Mobarakai N |title=Hematologic manifestations of babesiosis |journal=Ann Clin Microbiol Antimicrob |volume=16 |issue=1 |page=6 |date=February 2017 |pmid=28202022 |pmc=5310009 |doi=10.1186/s12941-017-0179-z |doi-access=free}}</ref>

In animals, babesiosis is suspected by observation of clinical signs (hemoglobinuria and anemia) in animals in endemic areas. Diagnosis is confirmed by observation of merozoites on a thin film blood smear examined at maximum magnification under oil using Romonovski stains (methylene blue and eosin). This is a routine part of the veterinary examination of dogs and ruminants in regions where babesiosis is endemic.{{cn|date=August 2022}}

''Babesia canis'' and ''B.&nbsp;bigemina'' are "large ''Babesia'' species" that form paired merozoites in the erythrocytes, commonly described as resembling "two pears hanging together", rather than the "Maltese cross" of the "small ''Babesia'' species". Their merozoites are around twice the size of small ones.{{cn|date=August 2022}}

Cerebral babesiosis is suspected ''in vivo'' when neurological signs (often severe) are seen in cattle that are positive for ''B.&nbsp;bovis'' on blood smear, but this has yet to be proven scientifically. Outspoken red discoloration of the grey matter ''post-mortem'' further strengthens suspicion of cerebral babesiosis. Diagnosis is confirmed ''post-mortem'' by observation of ''Babesia''-infected erythrocytes sludged in the cerebral cortical capillaries in a brain smear.{{cn|date=January 2023}}

== Treatment ==
Treatment of asymptomatic carriers should be considered if parasites are still detected after 3 months. In mild-to-moderate babesiosis, the treatment of choice is a combination of [[atovaquone]] and [[azithromycin]]. This regimen is preferred to [[clindamycin]] and [[quinine]] because it has fewer side effects. The standard course is 7 to 10 days, but this is extended to at least 6 weeks in people with [[relapsing]] disease. Even mild cases are recommended to be treated to decrease the chance of inadvertently transmitting the infection by donating blood.<ref name="NEJM Babesiosis Review"/> In severe babesiosis, the combination of clindamycin and quinine is preferred. In life-threatening cases, [[exchange transfusion]] is performed.<ref>{{cite journal|last1=Tanyel |first1=Esra |last2=Guler |first2=Nil |last3=Hokelek |first3=Murat |last4=Ulger |first4=Fatma |last5=Sunbul |first5=Mustafa |title=A case of severe babesiosis treated successfully with exchange transfusion|journal=Int J Infect Dis|year=2015|pmid=26232090|doi=10.1016/j.ijid.2015.07.019 |volume=38 |pages=83–5|doi-access=free }}</ref> In this procedure, the infected red blood cells are removed and replaced with uninfected ones; toxins produced by the parasites may also be removed.<ref>{{cite journal |vauthors=Saifee NH, Krause PJ, Wu Y |title=Apheresis for babesiosis: Therapeutic parasite reduction or removal of harmful toxins or both? |journal=J Clin Apher |volume=31 |issue=5 |pages=454–8 |date=October 2016 |pmid=26481763 |doi=10.1002/jca.21429 }}</ref>

[[Imidocarb]] is a drug used for the treatment of [[Babesiosis of dogs|babesiosis in dogs]].<ref>{{cite web |url=http://www.merck-animal-health-usa.com/products/130_163327/productdetails_130_163631.aspx |title=Imizol {{!}} Overview |author=<!--Staff writer(s); no by-line.--> |publisher=Merck Animal Health |access-date=15 August 2015 |archive-url=https://web.archive.org/web/20150807190718/http://www.merck-animal-health-usa.com/products/130_163327/productdetails_130_163631.aspx |archive-date=7 August 2015 }}</ref>
Extracts of the poisonous, [[bulbous]] plant ''[[Boophone disticha]]'' are used in the [[folk medicine]] of [[South Africa]] to treat [[equine]] babesiosis. ''B.&nbsp;disticha'' is a member of the daffodil family [[Amaryllidaceae]] and has also been used in preparations employed as [[arrow poisons]], [[hallucinogens]], and in [[embalming]]. The plant is rich in [[alkaloids]], some of which display an action similar to that of [[Hyoscine hydrobromide|scopolamine]].<ref name=jad>{{cite web|first=James A.|last=Duke|author-link=James A. Duke|title="Boophone disticha" (Liliaceae)|publisher=Dr. Duke's Phytochemical and Ethnobotanical Databases|url=https://phytochem.nal.usda.gov/phytochem/ethnoPlants/show/8865|access-date=November 10, 2011|archive-date=January 15, 2018|archive-url=https://web.archive.org/web/20180115001244/https://phytochem.nal.usda.gov/phytochem/ethnoPlants/show/8865}}</ref>

== Epidemiology ==
Babesiosis is a [[Vector (epidemiology)|vector-borne]] illness usually transmitted by ''[[Ixodes scapularis]]'' [[tick]]s. ''B.&nbsp;microti'' uses the same tick vector as Lyme disease, and may occur in conjunction with Lyme.<ref name="Hunfeld"/> The organism can also be transmitted by blood transfusion.<ref>{{cite journal|vauthors=Herwaldt BL, Linden JV, Bosserman E, Young C, Olkowska D, Wilson M | title = Transfusion-associated babesiosis in the United States: a description of cases| journal = Ann Intern Med| year = 2011| volume = 155| issue = 8| pages = 509–19| pmid = 21893613| doi=10.7326/0003-4819-155-8-201110180-00362| doi-access = | s2cid = 74852997}}</ref><ref>{{cite journal| journal = Ann Intern Med| year = 2011| volume = 155| issue = 8| pages = 556–7| title = Transfusion-associated babesiosis: shouldn't we be ticked off?| author = Leiby DA| pmid = 21893616| doi=10.7326/0003-4819-155-8-201110180-00363| doi-access = | s2cid = 807441}}</ref> [[Ticks of domestic animals]], especially ''Rhipicephalus (Boophilus) microplus'' and ''R. (B.) decoloratus'' transmit several species of ''Babesia'' to livestock, causing considerable economic losses to farmers in tropical and subtropical regions.{{cn|date=August 2022}}

In the United States, the majority of babesiosis cases are caused by ''B.&nbsp;microti'', and occur in the Northeast and northern Midwest from May through October.<ref name="NEJM Babesiosis Review" /> Areas with especially high rates include eastern [[Long Island]], [[Fire Island]], [[Nantucket Island]], and [[Martha's Vineyard]].<ref>{{cite book |first1=A. James |last1=Giannini |first2=Henry R. |last2=Black |first3=Roger L. |last3=Goettsche |title=Psychiatric, psychogenic, and somatopsychic disorders handbook: a laboratory and clinical guide to the medical management of emotional and intellectual pathology |url=https://books.google.com/books?id=LCBsAAAAMAAJ |year=1978 |publisher=Medical Examination |isbn=978-0-87488-596-5 |page=86 |access-date=2016-10-14 |archive-date=2020-07-26 |archive-url=https://web.archive.org/web/20200726152514/https://books.google.com/books?id=LCBsAAAAMAAJ |url-status=live }}</ref><ref>{{cite news | last = Belluck | first = Pam | title = Tick-Borne Illnesses Have Nantucket Considering Some Deer-Based Solutions | work = [[The New York Times]] | url = https://www.nytimes.com/2009/09/06/us/06nantucket.html | access-date = September 6, 2009 | date = September 6, 2009 | archive-date = November 15, 2011 | archive-url = https://web.archive.org/web/20111115071438/http://www.nytimes.com/2009/09/06/us/06nantucket.html | url-status = live }}</ref><ref name=Herwaldt>{{cite journal|vauthors=Herwaldt BL, Persing DH, Précigout EA |title=A fatal case of babesiosis in Missouri: Identification of another piroplasm that infect humans |journal=Annals of Internal Medicine |volume=124 |issue=7 |pages=643–50 |year=1996 |pmid=8607592 |doi=10.7326/0003-4819-124-7-199604010-00004 |s2cid=46733758 |display-authors=etal }}</ref><ref>{{cite journal |author=Mylonakis E |title=When to suspect and how to monitor babesiosis |journal=Am Fam Physician |volume=63 |issue=10 |pages=1969–74 |date=May 2001 |pmid=11388711 |url=http://www.aafp.org/link_out?pmid=11388711 |access-date=2012-05-26 |archive-date=2022-07-21 |archive-url=https://web.archive.org/web/20220721141444/https://www.aafp.org/pubs/afp/issues/2001/0515/p1969.html |url-status=live }}</ref><ref>{{cite web | url = https://www.cdc.gov/parasites/babesiosis/gen_info/faqs.html | publisher = [[Centers for Disease Control and Prevention]] (CDC | date = May 5, 2009 | access-date = September 6, 2009 | title = Babesiosis FAQs | archive-date = November 28, 2010 | archive-url = https://web.archive.org/web/20101128002053/http://www.cdc.gov/parasites/babesiosis/gen_info/faqs.html | url-status = live }}</ref>
The [[Centers for Disease Control and Prevention]] now requires state health departments to report infections using [https://www.cdc.gov/parasites/babesiosis/resources/50.153.pdf Form OMB No. 0920-0728].<ref>{{cite web |title=Parasites - Babesiosis: National Surveillance |url=https://www.cdc.gov/parasites/babesiosis/surveillance.html |website=Centers for Disease Control and Prevention |access-date=19 June 2018 |archive-url=https://web.archive.org/web/20171216225718/https://www.cdc.gov/parasites/babesiosis/surveillance.html |archive-date=December 16, 2017}}</ref> In 2014, Rhode Island had an incidence of 16.3 reported infections per 100,000 people.<ref>{{cite web |last1=Centers for Disease Control and Prevention |title=Data & Statistics |url=https://www.cdc.gov/parasites/babesiosis/data-statistics/index.html |website=Center |access-date=19 June 2018 |archive-date=19 June 2018 |archive-url=https://web.archive.org/web/20180619040122/https://www.cdc.gov/parasites/babesiosis/data-statistics/index.html |url-status=live }}</ref>

In Europe, ''B.&nbsp;divergens'' is the primary cause of infectious babesiosis and is transmitted by ''I.&nbsp;ricinus''.<ref name="NEJM Babesiosis Review" />

Babesiosis has emerged in the Lower Hudson Valley, New York, since 2001.<ref>{{cite journal| title = Babesiosis in Lower Hudson Valley, New York, USA| volume = 17| issue = 5|date=May 2011|vauthors=Joseph JT, Roy SS, Shams N, Visintainer P, Nadelman RB, Hosur S | journal = Emerg Infect Dis| doi = 10.3201/eid1705.101334 |pmid=21529393 |pmc=3321771| pages = 843–7|display-authors=etal}}<br />
'''Related news articles:'''
{{cite news| url = https://www.nytimes.com/2011/06/21/health/21ticks.html| title = Once Rare, Infection by Tick Bites Spreads| author = Laurie Tarkan| work = [[The New York Times]]| date = June 20, 2011| access-date = February 24, 2017| archive-date = November 25, 2016| archive-url = https://web.archive.org/web/20161125100535/http://www.nytimes.com/2011/06/21/health/21ticks.html| url-status = live}}</ref>

In Australia, one locally-acquired case of ''B.&nbsp;microti'' has been reported, which was fatal.<ref name="senanayake">{{cite journal |last1=Senanayake |first1=Sanjaya N |last2=Paparini |first2=Andrea |last3=Latimer |first3=Maya |last4=Andriolo |first4=Kerrie |last5=Dasilva |first5=Alexandre J |last6=Wilson |first6=Heather |last7=Xayavong |first7=Maniphet V |last8=Collignon |first8=Peter J |last9=Jeans |first9=Phillip |last10=Irwin |first10=Peter J |title=First report of human babesiosis in Australia |journal=Medical Journal of Australia |date=March 2012 |volume=196 |issue=5 |pages=350–2 |doi=10.5694/mja11.11378|pmid=22432676 |s2cid=33068508 }}</ref> A subsequent investigation found no additional evidence of human babesiosis in over 7000 patient samples, leading the authors to conclude that babesiosis was rare in Australia.<ref name="faddy-2019">{{cite journal |last1=Faddy |first1=Helen M. |last2=Rooks |first2=Kelly M. |last3=Irwin |first3=Peter J. |last4=Viennet |first4=Elvina |last5=Paparini |first5=Andrea |last6=Seed |first6=Clive R. |last7=Stramer |first7=Susan L. |last8=Harley |first8=Robert J. |last9=Chan |first9=Hiu-Tat |last10=Dennington |first10=Peta M. |last11=Flower |first11=Robert L.P. |title=No evidence for widespread Babesia microti transmission in Australia |journal=Transfusion |date=July 2019 |volume=59 |issue=7 |pages=2368–74 |doi=10.1111/trf.15336|pmid=31070793 |s2cid=148570372 }}</ref> A similar disease in cattle, commonly known as tick fever, is spread by ''[[Babesia bovis]]'' and [[Babesia bigemina|''B. bigemina'']] in the introduced cattle tick ''[[Rhipicephalus microplus]]''.  This disease is found in eastern and northern Australia.<ref name="PIF">{{cite web|title=Tick fever (bovine babesiosis) |author=Queensland Government, Department of Primary Industries and Fisheries |url=http://www.dpi.qld.gov.au/4790_5838.htm |access-date=21 February 2012 |archive-url=https://web.archive.org/web/20110405112007/http://www.dpi.qld.gov.au/4790_5838.htm |archive-date=5 April 2011 }}</ref>

===Isolated cases===
A table of isolated cases of babesiosis, which may be underestimated given how widely distributed the tick vectors are in temperate latitudes.<ref name="NEJM Babesiosis Review" />
{| class="wikitable sortable"
|-
! Location !! Species
|-
| Pacific Coast (northern California to Washington) || ''B. duncani''
|-
| [[Kentucky]], [[Missouri]], and [[Washington (state)|Washington]] || ''B. divergens''
|-
| [[Austria]], [[Germany]], [[Italy]] || ''B. venatorum''
|-
| [[Canary Islands]] || ''B. microti''
|-
| Africa ([[Egypt]], [[Mozambique]], [[South Africa]]) || Uncharacterized spp.
|-
| Asia ([[Taiwan]], [[Japan]]) || ''B. microti''
|-
| [[South Korea]] ||'' Babesia'' KO1<ref name="pmid17392446">{{cite journal |vauthors=Kim JY, Cho SH, Joo HN |title=First case of human babesiosis in Korea: detection and characterization of a novel type of Babesia sp. (KO1) similar to ovine babesia |journal=J. Clin. Microbiol. |volume=45|issue=6 |pages=2084–7 |date=June 2007 |pmid=17392446 |pmc=1933034 |doi=10.1128/JCM.01334-06|url=|display-authors=etal}}</ref>
|-
| Australia || ''B. microti''<ref name="faddy-2019" />
|-
| South America (Brazil, Colombia) || Uncharacterized spp.
|}

==History==
The disease is named for the genus of the causative organism,<ref>[https://www.merriam-webster.com/dictionary/babesia "babesia"] {{Webarchive|url=https://web.archive.org/web/20220424212822/https://www.merriam-webster.com/dictionary/babesia |date=2022-04-24 }} at [[Webster's Dictionary|Merriam-Webster]] online.</ref> which was named after the [[Romanian people|Romanian]] [[bacteriologist]] [[Victor Babeș]].<ref>{{WhoNamedIt|doctor|367|Victor Babeș}}</ref> In 1888, Victor Babeș identified the microorganisms in red blood cells as the cause of febrile [[hemoglobinuria]] in cattle.<ref name="NEJM Babesiosis Review">{{cite journal|last1=Vannier|first1=Edouard|last2=Krause|first2=Peter J.|title=Human Babesiosis|journal=New England Journal of Medicine|date=21 June 2012|volume=366|issue=25|pages=2397–2407|doi=10.1056/NEJMra1202018|pmid=22716978|s2cid=205116383 |url=https://dermatologycentral.typepad.com/files/nejmra1202018.pdf|url-status=live|archive-url=https://web.archive.org/web/20211112081212/https://dermatologycentral.typepad.com/files/nejmra1202018.pdf|archive-date=2021-11-12}}</ref> In 1893, [[Theobald Smith]] and Frederick Kilborne discovered that a tick was the vector for transmission in Texas cattle. The agent was ''B.&nbsp;bigemina''. This was the first demonstration that an [[arthropod]] could act as a [[disease vector]] to transmit an infectious agent to a vertebrate host.{{cn|date=August 2022}}

In 1957, the first human case was documented in a [[splenectomy|splenectomized]] Croatian herdsman.<ref name="NEJM Babesiosis Review" /> The agent was ''B.&nbsp;divergens''. In 1969, the first case was reported in an [[immunocompetent]] individual on Nantucket Island. The agent was ''B.&nbsp;microti'', and the vector was the tick ''[[Ixodes scapularis|I. scapularis]]''.{{citation needed|date=June 2016}} [[Horse|Equine]] babesiosis (caused by the protozoan ''[[Theileria#Important species|Theileria equi]]'') is also known as piroplasmosis (from the [[Latin language|Latin]] {{Lang|la|piro}}, meaning [[pear]] + [[Greek language|Greek]] ''plasma'', a thing formed).<ref name=lexic>{{cite web|url=https://www.lexic.us/definition-of/piroplasma|title=Definition of Piroplasma|publisher=lexic.us|access-date=November 9, 2011|archive-date=November 11, 2011|archive-url=https://web.archive.org/web/20111111142406/http://www.lexic.us/definition-of/Piroplasma|url-status=live}}</ref>

==Other animals==
Veterinary treatment of babesiosis does not normally use antibiotics. In livestock and  animals, [[diminazen]] (Berenil), [[imidocarb]], or [[trypan blue]] would be the drugs of choice for treatment of ''B.&nbsp;canis rossi'' (dogs in Africa), ''B.&nbsp;bovis'', and ''B.&nbsp;bigemina'' (cattle in Southern Africa). In acute cases in cattle, a blood transfusion may be carried out.  A vaccine is effective against ''B.&nbsp;canis canis'' (dogs in the Mediterranean region), but is ineffective against ''B.&nbsp;c.&nbsp;rossi''. ''B.&nbsp;imitans'' causes a mild form of the disease that frequently resolves without treatment (dogs in Southeast Asia).{{cn|date=January 2023}}

== References ==
{{Reflist}}

== External links ==
{{Wikispecies|Babesia}}
* {{cite web |author=Center for Global Health |title=Babesiosis |date=2019-06-25 |work=Parasites and Health, DPDx—Laboratory Identification of Parasites of Public Health Concern |publisher=Centers for Disease Control & Prevention |url=http://www.dpd.cdc.gov/dpdx/HTML/Babesiosis.htm |access-date=2003-10-07 |archive-url=https://web.archive.org/web/20130307053855/http://www.dpd.cdc.gov/dpdx/HTML/Babesiosis.htm |archive-date=2013-03-07 }} [[Public domain]] source from which the first version of this article was derived.
* {{cite journal |last1=Krause |first1=Peter J |last2=Auwaerter |first2=Paul G |last3=Bannuru |first3=Raveendhara R |last4=Branda |first4=John A |last5=Falck-Ytter |first5=Yngve T |last6=Lantos |first6=Paul M |last7=Lavergne |first7=Valéry |last8=Meissner |first8=H Cody |last9=Osani |first9=Mikala C |last10=Rips |first10=Jane Glazer |last11=Sood |first11=Sunil K |last12=Vannier |first12=Edouard |last13=Vaysbrot |first13=Elizaveta E |last14=Wormser |first14=Gary P |title=Clinical Practice Guidelines by the Infectious Diseases Society of America (IDSA): 2020 Guideline on Diagnosis and Management of Babesiosis |journal=Clinical Infectious Diseases |date=27 January 2021 |volume=72 |issue=2 |pages=e49–e64 |doi=10.1093/cid/ciaa1216 |pmid=33252652 |url=https://academic.oup.com/cid/article/72/2/e49/6012666|doi-access=free }}
* {{cite journal |vauthors=Homer MJ, Aguilar-Delfin I, Telford SR, Krause PJ, Persing DH |title=Babesiosis |journal=Clin. Microbiol. Rev. |volume=13 |issue=3 |pages=451–69 |date=July 2000 |pmid=10885987 |pmc=88943 |doi= 10.1128/CMR.13.3.451-469.2000}}
* [https://web.archive.org/web/20021115013840if_/http://www.merckvetmanual.com:80/mvm/index.jsp?cfile=htm/bc/10402.htm "Babesiosis: Overview"]—''The Merck Veterinary Manual''
* [https://web.archive.org/web/20120913002322/http://www.oie.int/wahis_2/public/wahid.php/Diseaseinformation/Diseasehome Current status of Equine piroplasmosis worldwide] at OIE. WAHID Interface—OIE World Animal Health Information Database
* [https://www.woah.org/en/what-we-do/animal-health-and-welfare/animal-diseases/ Disease card]—OIE

{{Medical resources
|   ICD10          = {{ICD10|B|60|0|b|50}}
|   ICD9           = {{ICD9|088.82}}
|   ICDO           =
|   OMIM           =
|   DiseasesDB     = 1200
|   MedlinePlus    =
|   eMedicineSubj  =
|   eMedicineTopic =
|   MeshID         = D001404
| Orphanet=108
}}
{{Chromalveolate diseases}}
{{Tick-borne diseases}}
{{Flea-borne diseases}}

[[Category:Babesia]]
[[Category:Protozoal diseases]]
[[Category:Tick-borne diseases]]
[[Category:Zoonoses]]