Leishmania spp

From Cow
Amastigotes of L. donovani in skin lesions smear
Cutaneous leishmaniosis on the lower jaw of a cow

Leishmania spp are a protozoan parasite which cause leishmaniosis in cattle and visceral leishmaniasis in humans[1] in the Mediterranean area, the Middle East, Asia and East Africa.

Although cattle often show serological exposure, they are not thought to play a role of reservoir for this parasite[2].

Transmission is by Phlebotomus spp[3][4] and Lutzomyia spp sand flies[5].

Species recognized as pathogenic in cattle include:

  • Leishmania donovani[6]
  • Leishmania siamensis[7]
  • Leishmania infantum (L. chagasi)
  • Leishmania braziliensis

Clinical signs

Most cattle are subclinically affected by this parasite, although cutaneous lesions do occur.

In severely affected cattle, fever, lymphadenopathy and skin ulcerations predominate.

Diagnosis

Diagnosis is based on presenting clinical signs supported by laboratory isolation of the parasite in blood and skin impressions.

Immunofluorescence assays, ELISA, direct agglutination and PCR assays are currently used to assist definitive diagnosis.

Treatment

Treatment in cattle requires the use of the antiprotozoal drug N-methylglucamine antimoniate. Allopurinol, Miltefosine and Amphotericin B have also been reported as eefective.

Repellants or control of breeding ground where sandlfies colonise is important to prevent recurrences.

References

  1. Bhattarai NR et al (2010) Domestic animals and epidemiology of visceral leishmaniasis, Nepal. Emerg Infect Dis 16(2):231-237
  2. Alam MS et al (2011) Survey of domestic cattle for anti-Leishmania antibodies and Leishmania DNA in a visceral leishmaniasis endemic area of Bangladesh. BMC Vet Res 7:27
  3. Svobodová M et al (2009) Cutaneous leishmaniasis caused by Leishmania infantum transmitted by Phlebotomus tobbi. Int J Parasitol 39(2):251-256
  4. Gebre-Michael T et al (2010) Further studies on the phlebotomine sandflies of the kala-azar endemic lowlands of Humera-Metema (north-west Ethiopia) with observations on their natural blood meal sources. Parasit Vectors 3(1):6
  5. Noguera P et al (2006) Effect of blood source on the survival and fecundity of the sandfly Lutzomyia ovallesi Ortiz (Diptera: Psychodidae), vector of Leishmania. Biomedica 26(1):57-63
  6. Khanal B et al (2010) Spatial analysis of Leishmania donovani exposure in humans and domestic animals in a recent kala azar focus in Nepal. Parasitology 137(11):1597-1603
  7. Lobsiger L et al (2010) An autochthonous case of cutaneous bovine leishmaniasis in Switzerland. Vet Parasitol 169(3-4):408-414