Isolation and molecular characterization of T. gondii from Suricata suricatta with fatal toxoplasmosis in Argentina.

BASSO W.; MORÉ G.; QUIROGA M.A.; PARDINI L.; BACIGALUPE D.; MAKSIMOV P.; VALENZUELA M.C.; BALDUCCHI D.; VENTURINI M.C.; VENTURINI L.; SCHARES G.

University of Hamburg, Bernhard-Nocht Institute for Tropical Medicine.Alemania

Congreso; XXIII Anual Meeting of the German Society for Parasitology; 2008

Toxoplasma gondii infection is frequently asymptomatic; however, it can be severe or even fatal to some hosts. Some species like New World monkeys, lemurs, Pallas cats and some Australian marsupials are considered highly susceptible to clinical toxoplasmosis. In this study, the diagnosis of fatal disseminated toxoplasmosis in captive slender-tailed meerkats (Suricata suricatta) in the Zoo La Plata, Argentina and the in-vitro isolation and molecular characterization of T. gondii is reported. Between January and April 2007 6/18 meerkats died.  Samples from 3 dead animals were processed. The animals showed depression, dyspnea, hypothermia, and ataxia in one case and died within 1-5 days. The main histopathological lesions included interstitial pneumonia (3/3), non-suppurative inflammatory changes and focal necrosis in liver (3/3), spleen (2/3), kidney (2/3) and brain (1/3 meerkats). Tachyzoites were present in lung (3/3), liver (3/3), spleen (1/3), brain (2/3) and mesenteric lymph nodes sections (1/3 meerkats), and stained using T. gondii anti-serum in immunohistochemical staining. T. gondii was isolated in N: NIH Swiss mice and in BM cell cultures from tissues of one of the meerkats. 8/9 mice had IFAT and MAT titers  800 or greater for T. gondii and remained asymptomatic for over 48 days post infection. T. gondii DNA was demonstrated using the B22-B23 specific primers in tissues of all 3 animals and in tachyzoites isolated in cell cultures. Nested PCR of markers based in 3¡¯-SAG2, 5¡¯-SAG2, BTUB, GRA6 and SAG3 loci of T. gondii produced amplicons that were identified as corresponding to genotype III by RFLP analysis in all samples. Although type III strains of T. gondii are usually not virulent in the mouse model, the pathogenicity in other animal species is uncertain. In the present case, T. gondii from clonal type III lineage was responsible of fatal cases in S. suricatta.