Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Datasheet

Trypanosoma evansi

Toolbox

Datasheet

Trypanosoma evansi

Summary

  • Last modified
  • 14 May 2019
  • Datasheet Type(s)
  • Invasive Species
  • Preferred Scientific Name
  • Trypanosoma evansi
  • Taxonomic Tree
  • Domain: Eukaryota
  •   Kingdom: Protista
  •     Phylum: Protozoa
  •       Subphylum: Sarcomastigophora
  •         Order: Kinetoplastida
  • Summary of Invasiveness
  • Trypanosoma evansi is a protozoan parasite that is the causative agent of the animal disease surra.  The disease occurs in a wide area from the northern part of Africa through the Middle East to Southeast Asia;...

  • Principal Source
  • Draft datasheet under review

  • There are no pictures available for this datasheet

    If you can supply pictures for this datasheet please contact:

    Compendia
    CAB International
    Wallingford
    Oxfordshire
    OX10 8DE
    UK
    compend@cabi.org
  • Distribution map More information

Don't need the entire report?

Generate a print friendly version containing only the sections you need.

Generate report

Identity

Top of page

Preferred Scientific Name

  • Trypanosoma evansi (Steel, 1885) Balbiani, 1888

Other Scientific Names

  • Spirochaeti evansi Steel, 1885
  • Trypanosoma brucei evansi

Summary of Invasiveness

Top of page

Trypanosoma evansi is a protozoan parasite that is the causative agent of the animal disease surra.  The disease occurs in a wide area from the northern part of Africa through the Middle East to Southeast Asia; it is thought to have been introduced to the Americas in the 16th century and is now found in much of Latin America except the southernmost parts.  It is not known to occur in North America (except Mexico), Australia, Europe (except for rare introductions into Spain and France), or northern Russia. It affects a very large range of domestic and wild animals; only one case of human infection has been reported. It has a significant economic and animal health impact on cattle, camels and other livestock in many countries. T. evansi is mechanically transmitted primarily by several species of haematophagous flies (mainly Tabanids and Stomoxes), but in Latin America the vampire bat (Desmodus rotundus) is a vector and reservoir host.  Clinical manifestations of disease include fever, anaemia, loss of appetite, weight loss, nervous signs, abortion, cachexia, and potentially death.  No vaccine is available.  Several chemotherapeutic drugs are used for the prophylaxis and treatment of surra; however, drug resistance is known to occur. Surra is on the OIE list of notifiable diseases.

Taxonomic Tree

Top of page
  • Domain: Eukaryota
  •     Kingdom: Protista
  •         Phylum: Protozoa
  •             Subphylum: Sarcomastigophora
  •                 Order: Kinetoplastida
  •                     Family: Trypanosomatidae
  •                         Genus: Trypanosoma
  •                             Species: Trypanosoma evansi

Notes on Taxonomy and Nomenclature

Top of page

Trypanosomes are protozoan parasites of the blood and sometimes tissues of many animal species.  They are taxonomically assigned to the order Kinetoplastida, family Trypanosomatidae, and genus Trypanosoma. The name is derived from the Greek trypano (borer) and soma (body) because of the corkscrew-like motion of some trypanosomatid species.  The genus Trypanosoma is known from fossils in Dominican amber represented by the extinct species T. antiquus (Poinar, 2005).  T. evansi belongs to the T. brucei group within the subgenus Trypanozoon (Desquesnes et al., 2013).  In fact, recent whole genome sequencing and analysis support the idea that T. evansi should be classified as a subspecies of T. brucei (Carnes et al., 2015). Desquesnes et al. (2013) discussed this and concluded that, as the genetic evidence was not unequivocal, and T. evansi shows strong biological, ecological and medical differences from T. brucei, it was advisable to retain the name T. evansi. T. equinum, affecting horses in South America, was previously regarded as a separate species but is now considered to be a dyskinetoplastic variant of T. evansi (Stevens and Brisse, 2004).

Infection with T. evansi causes a disease named ‘surra’ in India, El debab, El gafar, Tabourit or Mbori in North Africa and Mal de Caderas or Murrina in Latin America (OIE, 2012).  The origin of 'surra' is from the Marathi sūra, meaning “the sound of heavy breathing through the nostrils”.  A parasite that would later be named T. evansi was first identified and described as the causative agent of surra by Griffith Evans in 1880 while working in India. A young veterinarian named J.H. Steel, believing that the causative organisms were spirochaetes, named them Spirochaeti evansi.  Several years later, the taxonomic error was corrected, and they were placed in the genus Trypanosoma (Fallis, 1986).

Distribution

Top of page

Trypanosoma evansi has the widest geographical distribution among the trypanosomes.  In the Eastern Hemisphere, its geographical distribution is continuous from the northern part of Africa through the Middle East to Southeast Asia.  In Africa, it is present in all countries where camels are present.  It is found in sub-Saharan and Mediterranean climates, as well as in arid deserts and semiarid steppes.  It is present in the Arabian Peninsula, Turkey, Afghanistan, Pakistan, and has been occasionally reported from Bulgaria (Desquesnes et al., 2013).  It is also present throughout southern Asia, including India, China, Mongolia, parts of Russia, Bhutan, Nepal, Myanmar, Laos, Vietnam, Cambodia, Thailand, Malaysia, the Philippines, and Indonesia (Luckins, 1988).  Its presence was suspected in Papua New Guinea, but not confirmed, and it is so far absent from Australia (Reid, 2002) (it was briefly introduced there in the early 20th century but was soon eradicated -- Desquesnes et al., 2013, citing Hoare, 1972).  In Latin America, it is present in much of South America other than the southernmost parts, and it is uncertain how far north through Central America its range extends -- some reports suggest Mexico, but this is not certain (Desquesnes, 2004).  In Europe, there have been recent introductions of T. evansi in the Canary Islands (Spain) (Gutiérrez et al., 1998), the Spanish mainland (Tamarit et al., 2010), and a single epizootic in France resulting from infected camels imported from the Canary Islands (Desquesnes et al., 2008).  The parasite is absent from North America, northern Europe, and northern Russia (Desquesnes et al., 2013).

Distribution Table

Top of page

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Continent/Country/RegionDistributionLast ReportedOriginFirst ReportedInvasiveReferenceNotes

Asia

AfghanistanPresentDesquesnes et al., 2013
AzerbaijanNo information availableOIE Handistatus, 2005
BahrainDisease never reportedOIE Handistatus, 2005
BangladeshPresentMisra et al., 2016
BhutanPresentLuckins, 1988; OIE Handistatus, 2005
Brunei DarussalamNo information availableOIE Handistatus, 2005
CambodiaPresentLuckins, 1988
ChinaPresentLuckins, 1988
-Hong KongDisease not reportedOIE Handistatus, 2005
Georgia (Republic of)Disease never reportedOIE Handistatus, 2005
IndiaPresentHoare, 1972
IndonesiaPresentLuckins, 1988; OIE Handistatus, 2005
IranLast reported2000OIE Handistatus, 2005
IraqPresentOIE Handistatus, 2005; Desquesnes et al., 2013
IsraelPresentOIE Handistatus, 2005; Desquesnes et al., 2013
JapanDisease never reportedOIE Handistatus, 2005
JordanPresentOIE Handistatus, 2005; Desquesnes et al., 2013
KazakhstanPresentOIE Handistatus, 2005; Desquesnes et al., 2013
Korea, DPRDisease not reportedOIE Handistatus, 2005
Korea, Republic ofDisease never reportedOIE Handistatus, 2005
KuwaitDisease not reportedOIE Handistatus, 2005
LaosPresentLuckins, 1988
LebanonPresentOIE Handistatus, 2005; Desquesnes et al., 2013
MalaysiaPresentLuckins, 1988
MongoliaPresentLuckins, 1988; OIE Handistatus, 2005
MyanmarPresentLuckins, 1988; OIE Handistatus, 2005
NepalPresentLuckins, 1988; OIE Handistatus, 2005
OmanPresentOIE Handistatus, 2005; Desquesnes et al., 2013
PakistanPresentDesquesnes et al., 2013
PhilippinesPresentLuckins, 1988; OIE Handistatus, 2005
QatarDisease not reportedOIE Handistatus, 2005
Saudi ArabiaPresentOIE Handistatus, 2005; Desquesnes et al., 2013
SingaporeDisease never reportedOIE Handistatus, 2005
Sri LankaNo information availableOIE Handistatus, 2005
SyriaPresentOIE Handistatus, 2005; Desquesnes et al., 2013
TaiwanDisease not reportedOIE Handistatus, 2005
TajikistanNo information availableOIE Handistatus, 2005
ThailandPresentLuckins, 1988; OIE Handistatus, 2005
TurkeyPresentOIE Handistatus, 2005; Desquesnes et al., 2013
TurkmenistanDisease not reportedOIE Handistatus, 2005
United Arab EmiratesPresentDesquesnes et al., 2013
UzbekistanDisease not reportedOIE Handistatus, 2005
VietnamPresentLuckins, 1988; OIE Handistatus, 2005
YemenNo information availableOIE Handistatus, 2005

Africa

AlgeriaPresentHoare, 1972; OIE Handistatus, 2005
AngolaNo information availableOIE Handistatus, 2005
BeninNo information availableOIE Handistatus, 2005
BotswanaDisease never reportedOIE Handistatus, 2005
Burkina FasoPresentHoare, 1972; OIE Handistatus, 2005
BurundiDisease never reportedOIE Handistatus, 2005
CameroonNo information availableOIE Handistatus, 2005
Cape VerdeDisease never reportedOIE Handistatus, 2005
Central African RepublicDisease not reportedOIE Handistatus, 2005
ChadPresentHoare, 1972; OIE Handistatus, 2005
Congo Democratic RepublicDisease not reportedOIE Handistatus, 2005
Côte d'IvoireDisease not reportedOIE Handistatus, 2005
DjiboutiReported present or known to be presentOIE Handistatus, 2005
EgyptPresentHoare, 1972; OIE Handistatus, 2005
EritreaPresentHoare, 1972; OIE Handistatus, 2005
EthiopiaPresentHoare, 1972; OIE Handistatus, 2005
GhanaDisease not reportedOIE Handistatus, 2005
GuineaDisease never reportedOIE Handistatus, 2005
Guinea-BissauNo information availableOIE Handistatus, 2005
KenyaPresentHoare, 1972
LibyaPresentHoare, 1972; OIE Handistatus, 2005
MadagascarDisease never reportedOIE Handistatus, 2005
MalawiNo information availableOIE Handistatus, 2005
MaliPresentHoare, 1972; OIE Handistatus, 2005
MauritaniaPresentHoare, 1972
MauritiusDisease not reportedOIE Handistatus, 2005
MoroccoPresentHoare, 1972; OIE Handistatus, 2005
MozambiqueNo information availableOIE Handistatus, 2005
NamibiaDisease never reportedOIE Handistatus, 2005
NigerPresentHoare, 1972
NigeriaPresentHoare, 1972; OIE Handistatus, 2005
RéunionDisease never reportedOIE Handistatus, 2005
RwandaNo information availableOIE Handistatus, 2005
Sao Tome and PrincipeDisease not reportedOIE Handistatus, 2005
SenegalPresentHoare, 1972; OIE Handistatus, 2005
SeychellesDisease not reportedOIE Handistatus, 2005
SomaliaPresentHoare, 1972; OIE Handistatus, 2005
South AfricaDisease never reportedOIE Handistatus, 2005
Spain
-Canary IslandsPresentIntroduced1995Gutiérrez et al., 1998
SudanPresentHoare, 1972; OIE Handistatus, 2005
SwazilandDisease never reportedOIE Handistatus, 2005
TanzaniaDisease never reportedOIE Handistatus, 2005
TogoNo information availableOIE Handistatus, 2005
TunisiaPresentHoare, 1972; OIE Handistatus, 2005
UgandaLast reported2001OIE Handistatus, 2005
ZambiaDisease never reportedOIE Handistatus, 2005
ZimbabweDisease never reportedOIE Handistatus, 2005

North America

BermudaDisease not reportedOIE Handistatus, 2005
CanadaDisease never reportedOIE Handistatus, 2005
MexicoAbsent, reported but not confirmedIntroducedDesquesnes, 2004; OIE Handistatus, 2005
USADisease never reportedOIE Handistatus, 2005

Central America and Caribbean

BarbadosDisease never reportedOIE Handistatus, 2005
BelizeDisease never reportedOIE Handistatus, 2005
British Virgin IslandsDisease never reportedOIE Handistatus, 2005
Cayman IslandsDisease never reportedOIE Handistatus, 2005
Costa RicaAbsent, reported but not confirmedIntroducedDesquesnes, 2004; OIE Handistatus, 2005
CubaDisease never reportedOIE Handistatus, 2005
CuraçaoDisease not reportedOIE Handistatus, 2005
DominicaDisease not reportedOIE Handistatus, 2005
Dominican RepublicDisease never reportedOIE Handistatus, 2005
El SalvadorDisease never reportedOIE Handistatus, 2005
GuadeloupeDisease not reportedOIE Handistatus, 2005
GuatemalaAbsent, reported but not confirmedIntroducedDesquesnes, 2004; OIE Handistatus, 2005
HaitiDisease never reportedOIE Handistatus, 2005
HondurasAbsent, reported but not confirmedIntroducedDesquesnes, 2004; OIE Handistatus, 2005
JamaicaNo information availableOIE Handistatus, 2005
MartiniqueDisease not reportedOIE Handistatus, 2005
NicaraguaAbsent, reported but not confirmedIntroducedDesquesnes, 2004; OIE Handistatus, 2005
PanamaPresentIntroducedDesquesnes, 2004; OIE Handistatus, 2005
Saint Kitts and NevisDisease never reportedOIE Handistatus, 2005
Saint Vincent and the GrenadinesDisease never reportedOIE Handistatus, 2005
Trinidad and TobagoDisease never reportedOIE Handistatus, 2005

South America

ArgentinaPresentIntroducedDesquesnes et al., 2013
BoliviaPresentIntroducedDesquesnes, 2004; OIE Handistatus, 2005
BrazilPresentIntroduced Invasive Desquesnes, 2004; OIE Handistatus, 2005As of 2004, spreading in Brazil with considerable clinical and economic consequences in newly infected regions
ChileLocalisedIntroducedDesquesnes, 2004; OIE Handistatus, 2005
ColombiaWidespreadIntroducedDesquesnes, 2004; OIE Handistatus, 2005
EcuadorAbsent, reported but not confirmedIntroducedDesquesnes, 2004; OIE Handistatus, 2005
Falkland IslandsDisease never reportedOIE Handistatus, 2005
French GuianaPresent, few occurrencesIntroducedDesquesnes, 2004; OIE Handistatus, 2005One case in a dog suggests presence in wild animals
GuyanaAbsent, formerly present1970IntroducedDesquesnes, 2004; OIE Handistatus, 2005
ParaguayPresentIntroducedDesquesnes, 2004; OIE Handistatus, 2005
PeruPresentIntroducedDesquesnes, 2004; OIE Handistatus, 2005
SurinamePresent, few occurrencesIntroducedDesquesnes, 2004A few reports in dogs; some PCR evidence of presence in cattle
UruguayDisease never reportedOIE Handistatus, 2005
VenezuelaPresentIntroducedDesquesnes, 2004; OIE Handistatus, 2005Enzootic throughout plains

Europe

AndorraDisease never reportedOIE Handistatus, 2005
AustriaDisease never reportedOIE Handistatus, 2005
BelarusDisease never reportedOIE Handistatus, 2005
BelgiumNo information availableOIE Handistatus, 2005
Bosnia-HercegovinaDisease not reportedOIE Handistatus, 2005
BulgariaPresent, few occurrencesOIE Handistatus, 2005; Desquesnes et al., 2013
CroatiaDisease never reportedOIE Handistatus, 2005
CyprusDisease never reportedOIE Handistatus, 2005
Czech RepublicDisease not reportedOIE Handistatus, 2005
DenmarkDisease never reportedOIE Handistatus, 2005
EstoniaDisease never reportedOIE Handistatus, 2005
FinlandDisease never reportedOIE Handistatus, 2005
FrancePresent, few occurrencesIntroduced2006OIE Handistatus, 2005; Desquesnes et al., 2008
GermanyDisease never reportedOIE Handistatus, 2005
GreeceDisease never reportedOIE Handistatus, 2005
HungaryDisease never reportedOIE Handistatus, 2005
IcelandDisease never reportedOIE Handistatus, 2005
IrelandDisease never reportedOIE Handistatus, 2005
Isle of Man (UK)Disease never reportedOIE Handistatus, 2005
ItalyNo information availableOIE Handistatus, 2005
JerseyDisease never reportedOIE Handistatus, 2005
LatviaDisease never reportedOIE Handistatus, 2005
LiechtensteinDisease not reportedOIE Handistatus, 2005
LithuaniaDisease never reportedOIE Handistatus, 2005
LuxembourgDisease not reportedOIE Handistatus, 2005
MacedoniaDisease never reportedOIE Handistatus, 2005
MaltaDisease never reportedOIE Handistatus, 2005
MoldovaDisease never reportedOIE Handistatus, 2005
NetherlandsDisease never reportedOIE Handistatus, 2005
NorwayDisease never reportedOIE Handistatus, 2005
PolandDisease never reportedOIE Handistatus, 2005
PortugalDisease not reportedOIE Handistatus, 2005
RomaniaDisease never reportedOIE Handistatus, 2005
Russian FederationOIE Handistatus, 2005Present based on regional distribution
-Southern RussiaPresentDesquesnes et al., 2013
-Western SiberiaPresentDesquesnes et al., 2013
SlovakiaDisease not reportedOIE Handistatus, 2005
SloveniaDisease not reportedOIE Handistatus, 2005
SpainPresent, few occurrencesIntroducedOIE Handistatus, 2005; Tamarit et al., 2010
SwedenDisease never reportedOIE Handistatus, 2005
SwitzerlandDisease never reportedOIE Handistatus, 2005
UKNo information availableOIE Handistatus, 2005
-Northern IrelandDisease never reportedOIE Handistatus, 2005
UkraineDisease never reportedOIE Handistatus, 2005
Yugoslavia (former)No information availableOIE Handistatus, 2005
Yugoslavia (Serbia and Montenegro)Disease not reportedOIE Handistatus, 2005

Oceania

AustraliaDisease never reportedOIE Handistatus, 2005
French PolynesiaDisease not reportedOIE Handistatus, 2005
New CaledoniaDisease never reportedOIE Handistatus, 2005
New ZealandDisease never reportedOIE Handistatus, 2005
SamoaDisease never reportedOIE Handistatus, 2005
VanuatuDisease never reportedOIE Handistatus, 2005
Wallis and Futuna IslandsNo information availableOIE Handistatus, 2005

History of Introduction and Spread

Top of page

Trypanosoma evansi was first described in 1880 from India.  However, it is thought to be derived from the African T. brucei brucei, which is restricted to the tsetse fly belt of Africa.  T. evansi is no longer able to undergo its cycle in the tsetse fly (Glossina sp.) due to the loss of the maxicircles of mitochondrial DNA; however, it is not known when this phenomenon occurred.  Historical data suggests that surra was already present in India at least several centuries B.C. (Desquesnes et al., 2013).  Apparently the parasite ultimately spread eastward from India, but the date of this initial spread is unknown.  The westward extension of T. evansi is more recent, however.  It is thought to have been introduced into Latin America in the 16th century with the Arabian horses belonging to the Spanish conquistadores (Hoare, 1965).  It was described for the first time on the Island of Marajo at the mouth of the Amazon River in Brazil in 1827; and was further observed in Paraguay in 1847; in the Pantanal, Brazil in 1850; and Mato Grosso, Brazil in 1860, before further spreading into Bolivia, Venezuela, Guyana, and Colombia (Hoare, 1972). 

In Europe, there have been recent introductions of T. evansi in the Canary Islands (Spain) (Gutiérrez et al., 1998) and the Spanish mainland (Tamarit et al., 2010), and a single epizootic in France in 2006 resulting from infected camels imported from the Canary Islands (Desquesnes et al., 2008).

Risk of Introduction

Top of page

Due to its wide host range, Trypanosoma evansi has the potential to invade new geographical areas, as shown by the recent incursions in continental Spain and France. Europe, North America and Australia might potentially be at risk (Desquesnes et al., 2013).

Pathogen Characteristics

Top of page

Trypanosoma evansi is classified within the genus Trypanosoma, subgenus Trypanozoon, along with T. brucei brucei (cause of nagana in livestock), T. brucei rhodesiense and T. brucei gambiense (cause of human African sleeping sickness), and T. equiperdum (cause of a sexually transmitted disease in horses).  When observed microscopically in fresh blood samples, T. evansi appears small with a thin posterior extremity and free flagellum.  There is also a highly visible undulating membrane.  When observed on a Giemsa stained thin smear, T. evansi is described as a monomorphic thin trypomastigote parasite (Desquesnes et al., 2013).  By comparison with T. brucei, it shows mostly slender forms with a long free flagellum and thin posterior extremity with subterminal small kinetoplast, but some intermediate (shorter free flagellum and posterior extremity) and rare “stumpy” forms have been reported. 

The mean length of the parasite is 24 ± 4 µm, which does not vary sustainably with geographical, host, or strain origin, but can change in relation to the growing conditions of the parasite and the immune response of the host (Tejero et al., 2008).  Like all pathogenic trypanosomes, T. evansi is covered by a dense protein layer consisting of a single protein called the variable surface glycoprotein (VSG) (Richards, 1984).

Two key, and related, biological features distinguish T. evansi from the T. brucei group.  First, its transmission is independent from the tsetse fly as an obligatory vector.  Second, all strains of T. evansi investigated so far are akinetoplastic or dyskinetoplastic, that is lacking all or critical parts, respectively, of the mitochondrial or kinetoplast DNA (kDNA).  T. brucei has a complex life cycle involving a vertebrate bloodstream stage and a procyclic stage in the tsetse fly.  In T. evansi a total or partial loss of kDNA has “locked” the trypanosome in the bloodstream form resulting in the elimination of the need for the tsetse fly vector. This has resulted in its ability to leave the African tsetse fly belt and spread to other continents (Lai et al., 2008; Lun and Desser, 1995), allowing T. evansi, along with T. equiperdum, to become one of the pathogenic trypanosomes with the widest geographical distribution.

Surra, the disease associated with this pathogen, is on the list of diseases notifiable to the World Organisation for Animal Health (OIE). Animal Health and Production Compendium users can refer to the AHPC library for further information from OIE, including the International Animal Health Code and the Manual of Standards for Diagnostic Tests and Vaccines. Also see the website: www.oie.int.

Vectors and Intermediate Hosts

Top of page
VectorSourceReferenceGroupDistribution
AtylotusInsect
ChrysopsInsect
Desmodus rotundusOtherSouth America|Central America|South America
HaematobiaInsect
HaematopotaInsect
MuscaInsect
StomoxysInsect
Stomoxys calcitransInsect
TabanidaeInsect
TabanusInsect

Economic Impact

Top of page

Several economically important animals, including camels, horses, buffaloes, and cattle, are particularly affected by surra (OIE, 2012).  Camels, for example, are a major part of the economies of many African and Middle East countries, being used for nomadic pastoralism, transportation, racing, and production of milk, wool and meat.  According to the United Nations Food and Agriculture Organization, the total world camel population is approximately 23 million animals (FAO, 2016), and surra is considered the most important single cause of morbidity and mortality in camels (OIE, 2013).  In addition to camels, Trypanosoma evansi and other livestock trypanosomes threaten 48 million cattle in 37 African countries and are responsible for major losses in the production of milk, meat, and manure fertilizer (Desquesnes et al., 2013).  In addition to Africa, T. evansi (and other animal trypanosomes) place a permanent constraint on raising livestock throughout much of Asia and Latin America.

Environmental Impact

Top of page

While Trypanosoma evansi infects a wide range of domestic and wild animals, clinical disease (surra) mainly affects domestic livestock.  Although infected wildlife can become reservoir hosts (i.e. asymptomatic carriers), the impact of T. evansi on biodiversity and the environment is minimal.

Risk and Impact Factors

Top of page Invasiveness
  • Proved invasive outside its native range
  • Has a broad native range
Impact outcomes
  • Host damage
  • Negatively impacts agriculture
  • Negatively impacts animal health
  • Negatively impacts livelihoods
Impact mechanisms
  • Pathogenic
Likelihood of entry/control
  • Difficult to identify/detect in the field
  • Difficult/costly to control

Gaps in Knowledge/Research Needs

Top of page

An effective vaccine against surra is sorely needed to control this disease.  This has not been possible to date due to the rapid turnover of the parasite’s outer surface glycoprotein (VSG), which also occurs in other animal and human pathogenic trypanosomes.  More research is needed to develop ways to stop or control this antigenic variation and/or develop new vaccine targets.

Another important area for future research is the development of new anti-trypanosome therapeutics, and drug resistance.  The major constraint to chemotherapeutic control of Trypanosoma evansi is the development of drug resistance. There are only a limited number of drugs available for the treatment of trypanosomiasis, and an even more limited number suitable for treatment of T. evansi infection in camels due to the toxicity of some of the available drugs in camels. In addition, these drugs have been in use over many decades, including use as prophylaxis, which can lead to increased drug resistance.

References

Top of page

Carnes, J., Anupama, A., Balmer, O., Jackson, A., Lewis, M., Brown, R., Cestari, I., Desquesnes, M., Gendrin, C., Hertz-Fowler, C., Imamura, H., Ivens, A., Korený, L., Lai DeHua, MacLeod, A., McDermott, S. M., Merritt, C., Monnerat, S., Moon, W. J., Myler, P., Phan, I., Ramasamy, G., Sivam, D., Lun ZhaoRong, Lukeš, J., Stuart, K. (et al), 2015. Genome and phylogenetic analyses of Trypanosoma evansi reveal extensive similarity to T. brucei and multiple independent origins for dyskinetoplasty. PLoS Neglected Tropical Diseases, 9(1), e3404. http://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0003404 doi: 10.1371/journal.pntd.0003404

Cross, G. A. M., 1975. Identification, purification and properties of clone-specific glycoprotein antigens constituting the surface coat of Trypanosoma brucei. Parasitology, 71(Pt 3), 393-417. doi: 10.1017/S003118200004717X

Desquesnes, M., 2004. Livestock trypanosomoses and their vectors in Latin America, [ed. by Desquesnes, M. ]. Paris, France: OIE (World Organisation for Animal Health).ix + 174 pp. https://www.oie.int/doc/ged/D9818.PDF

Desquesnes, M., Bossard, G., Patrel, D., Herder, S., Patout, O., Lepetitcolin, E., Thevenon, S., Berthier, D., Pavlovic, D., Brugidou, R., Jacquiet, P., Schelcher, F., Faye, B., Touratier, L., Cuny, G., 2008. First outbreak of Trypanosoma evansi in camels in metropolitan France. Veterinary Record, 162(23), 750-752. http://veterinaryrecord.bvapublications.com/archive/

Desquesnes, M., Bossard, G., Thévenon, S., Patrel, D., Ravel, S., Pavlovic, D., Herder, S., Patout, O., Lepetitcolin, E., Hollzmuller, P., Berthier, D., Jacquiet, P., Cuny, G., 2009. Development and application of an antibody-ELISA to follow up a Trypanosoma evansi outbreak in a dromedary camel herd in France. Veterinary Parasitology, 162(3/4), 214-220. http://www.sciencedirect.com/science/journal/03044017 doi: 10.1016/j.vetpar.2009.03.033

Desquesnes, M., Holzmuller, P., Lai DeHua, Dargantes, A., Lun ZhaoRong, Jittaplapong, S., 2013. Trypanosoma evansi and surra: a review and perspectives on origin, history, distribution, taxonomy, morphology, hosts, and pathogenic effects. BioMed Research International, 2013, Article ID 194176. http://www.hindawi.com/journals/bmri/2013/194176/

Diall O, Bajyana Songa E, Magnus E, Kouyate B, Diallo B, Van Meirvenne N, Hamers R, 1994. Evaluation of a direct serologic card agglutination test for the diagnosis of camel trypanosomiasis caused by Trypanosoma evansi. (Evaluation d'un test sérologique d'agglutination directe sur carte dans le diagnostic de la trypanosomose caméline à Trypanosoma evansi). Revue Scientifique et Technique, 13(3): 793-800

Fallis AM, 1986. Griffith Evans 1835-1935: Discoverer of the first pathogenic trypanosome. Canadian Veterinary Journal, 27(9): 336-338

FAO, 2016. FAOSTAT: Food and Agriculture Data. Rome, Italy: FAO. http://www.fao.org/faostat

Gutiérrez, C., Montoya, J. A., Padron, M., Corbera, J. A., Juste, M. C., Molina, J. M., 1998. Description of a case of trypanosomiasis due to Trypanosoma evansi in a dromedary in the Canary Islands. (Descripción de un caso de tripanosomosis en el dromedario por T. evansi en Canarias). Medicina Veterinaria, 15(6), 356-357.

Habila, N., Inuwa, M. H., Aimola, I. A., Udeh, M. U., Haruna, E., 2012. Pathogenic mechanisms of Trypanosoma evansi infections. Research in Veterinary Science, 93(1), 13-17. http://www.sciencedirect.com/science/journal/00345288 doi: 10.1016/j.rvsc.2011.08.011

Herrera, H. M., Dávila, A. M. R., Norek, A., Abreu, U. G., Souza, S. S., D'Andrea, P. S., Jansen, A. M., 2004. Enzootiology of Trypanosoma evansi in Pantanal, Brazil. Veterinary Parasitology, 125(3/4), 263-275. doi: 10.1016/j.vetpar.2004.07.013

Hoare, C. A., 1965. Vampire Bats as Vectors and Hosts of Equine and Bovine Trypanosomes. Acta Tropica, 22(3), 204-216.

Hoare, C. A., 1972. The trypanosomes of mammals. A zoological monograph, Blackwell Scientific Publications, 5 Alfred Street, Oxford.xvii + 749 pp.

Holland, W. G., Thanh, N. G., Do, T. T., Sangmaneedet, S., Goddeeris, B., Vercruysse, J., 2005. Evaluation of diagnostic tests for Trypanosoma evansi in experimentally infected pigs and subsequent use in field surveys in North Vietnam and Thailand. Tropical Animal Health and Production, 37(6), 457-467. http://springerlink.metapress.com/link.asp?id=103008 doi: 10.1007/s11250-005-1217-y

Horn, D., 2014. Antigenic variation in African trypanosomes. Molecular and Biochemical Parasitology, 195(2), 123-129. http://www.sciencedirect.com/science/article/pii/S0166685114000590 doi: 10.1016/j.molbiopara.2014.05.001

Igbokwe, I. O., Mohammed, A., 1991. The reticulocyte response to the anaemia in goats caused by experimental Trypanosoma brucei infection. Veterinary Research Communications, 15(5), 373-377. doi: 10.1007/BF00366994

Joshi, P. P., Shegokar, V. R., Powar, R. M., Herder, S., Rahul Katti, Salkar, H. R., Dani, V. S., Aradhana Bhargava, Jannin, J., Truc, P., 2005. Human trypanosomiasis caused by Trypanosoma evansi in India: the first case report. American Journal of Tropical Medicine and Hygiene, 73(3), 491-495.

Lai DeHua, Hashimi, H., Lun ZhaoRong, Ayala, F. J., Lukeš, J., 2008. Adaptations of Trypanosoma brucei to gradual loss of kinetoplast DNA: Trypanosoma equiperdum and Trypanosoma evansi are petite mutants of T. brucei. Proceedings of the National Academy of Sciences of the United States of America, 105(6), 1999-2004. http://www.pnas.org/ doi: 10.1073/pnas.0711799105

Luckins, A. G., 1988. Trypanosoma evansi in Asia. Parasitology Today, 4(5), 137-142.

Lun, Z. R., Desser, S. S., 1995. Is the broad range of hosts and geographical distribution of Trypanosoma evansi attributable to the loss of maxicircle kinetoplast DNA?. Parasitology Today, 11(4), 131-133.

Misra, K. K., Roy, S., Choudhury, A., 2016. Biology of Trypanosoma (Trypanozoon) evansi in experimental heterologous mammalian hosts. Journal of Parasitic Diseases, 40(3), 1047-1061. http://link.springer.com/article/10.1007/s12639-014-0633-1 doi: 10.1007/s12639-014-0633-1

OIE Handistatus, 2005. World Animal Health Publication and Handistatus II (data set for 2004). Paris, France: Office International des Epizooties

OIE, 2012. Trypanosoma evansi infection (Surra) (Chapter 2.1.21). In: Manual of Diagnostic Tests and Vaccines for Terrestrial Animals. Paris, France: OIE, 314-328. http://www.oie.int/fileadmin/Home/eng/Health_standards/tahm/2.01.21_TRYPANO_SURRA.pdf

OIE, 2013. Trypanosoma evansi infections (including surra). Paris, France: OIE, 4 pp. http://www.oie.int/fileadmin/Home/eng/Animal_Health_in_the_World/docs/pdf/Disease_cards/TRYPANO_EVANSI.pdf

Petersen C, Grinnage-Pulley TL, 2015. Trypanosomiasis. In: MSD Veterinary Manual. Kenilworth, New Jersey, USA: Merck Sharp & Dohme. http://www.merckvetmanual.com/mvm/circulatory_system/blood_parasites/trypanosomiasis.html

Poinar, G., Jr., 2005. Triatoma dominicana sp. n. (Hemiptera: Reduviidae: Triatominae), and Trypanosoma antiquus sp. n. (Stercoraria: Trypanosomatidae), the first fossil evidence of a triatomine-trypanosomatid vector association. Vector Borne and Zoonotic Diseases, 5(1), 72-81. doi: 10.1089/vbz.2005.5.72

Reid, S. A., 2002. Trypanosoma evansi control and containment in Australasia. Trends in Parasitology, 18(5), 219-224. doi: 10.1016/S1471-4922(02)02250-X

Reid, S. A., Copeman, D. B., 2003. The development and validation of an antibody-ELISA to detect Trypanosoma evansi infection in cattle in Australia and Papua New Guinea. Preventive Veterinary Medicine, 61(3), 195-208. doi: 10.1016/j.prevetmed.2003.07.004

Reid, S. A., Husein, A., Copeman, D. B., 2001. Evaluation and improvement of parasitological tests for Trypanosoma evansi infection. Veterinary Parasitology, 102(4), 291-297. doi: 10.1016/S0304-4017(01)00539-8

Richards, F. F., 1984. The surface of the African trypanosomes. Journal of Protozoology, 31(1), 60-64.

Sallau AB, Ibrahim MA, Salihu A, Yusuf IA, 2008. Bloodstream form of Trypanosoma evansi contains galactosidase. Middle East Journal of Science Research, 3: 49-52

Shegokar, V. R., Powar, R. M., Joshi, P. P., Aradhana Bhargava, Dani, V. S., Ravindra Katti, Zare, V. R., Khanande, V. D., Jannin, J., Truc, P., 2006. Human trypanosomiasis caused by Trypanosoma evansi in a village in India: preliminary serologic survey of the local population. American Journal of Tropical Medicine and Hygiene, 75(5), 869-870. http://www.ajtmh.org

Stevens, J. R., Brisse, S., 2004. Systematics of trypanosomes of medical and veterinary importance. In: The trypanosomiases, [ed. by Maudlin, I., Holmes, P. H., Miles, M. A.]. Wallingford, UK: CABI Publishing. 1-23. http://www.cabi.org/cabebooks/ebook/20043124834 doi: 10.1079/9780851994758.0001

Tamarit, A., Gutierrez, C., Arroyo, R., Jimenez, V., Zagalá, G., Bosch, I., Sirvent, J., Alberola, J., Alonso, I., Caballero, C., 2010. Trypanosoma evansi infection in mainland Spain. Veterinary Parasitology, 167(1), 74-76. http://www.sciencedirect.com/science/journal/03044017 doi: 10.1016/j.vetpar.2009.09.050

Tejero, F., Roschman-González, A., Perrone-Carmona, T. M., Aso, P. M., 2008. Trypanosoma evansi: a quantitative approach to the understanding of the morphometry-hematology relationship throughout experimental murine infections. Journal of Protozoology Research, 18(1), 34-47.

Verloo, D., Holland, W., My, L. N., Thanh, N. G., Tam, P. T., Goddeeris, B., Vercruysse, J., Büscher, P., 2000. Comparison of serological tests for Trypanosoma evansi natural infections in water buffaloes from north Vietnam. Veterinary Parasitology, 92(2), 87-96. doi: 10.1016/S0304-4017(00)00284-3

Vickerman, K., 1969. On the surface coat and flagellar adhesion in trypanosomes. Journal of Cell Science, 5(1), 163-93.

Wernery U, Kaaden OR, 2002. Infectious diseases in camelids (2nd ed.). Blackwell

Links to Websites

Top of page
WebsiteURLComment
OIE Reference Laboratories http://www.oie.int/en/our-scientific-expertise/reference-laboratories/list-of-laboratories
World Organization for Animal Health (OIE) http://www.oie.int

Organizations

Top of page

Japan: National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, , Inada-cho Nishi 2-13 Obihiro, Hokkaido 080-8555 , http://www.obihiro.ac.jp/~protozoa/eng/index-eng.html

France: World Organization for Animal Health (OIE), Paris, http://www.oie.int

Italy: Food and Agriculture Organization of the United Nations (FAO), Rome, http://www.fao.org

Principal Source

Top of page

Draft datasheet under review

Contributors

Top of page

20/01/2016 Original text by:

Chris Whitehouse, US Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD 21702-5011, USA.

Distribution Maps

Top of page
You can pan and zoom the map
Save map