The aim of this study was to determine the prevalence and risk factors associated with Toxoplasma gondii infection in domestic cats using an indirect-ELISA (IgM and IgG) and PCR. Samples collected from 220 cats from Merida, Yucatan, Mexico, were analyzed. Cases were reported as acute or chronic. Cases when positive to IgM and IgG and PCR were considered as reactivated chronic infection. Risk factors (sex, age, body condition, diet access to hunting, and number of cats in home) were assessed with a multivariate analysis, 75.5% (166/220) of the cats were IgM and 91.8% (202/220) IgG-seropositive and 79% were PCR-positive (173/220). Number of cats per household and low body condition score were associated with reactivated chronic infection (P < 0.05). It is concluded that T. gondii is scattered in the studied population with several periods of reinfection, and therefore an environmental contamination with infecting oocysts exists and there are intrinsic associated factors in cats that increase the risk of becoming infected.

The antiprotozoal activity in vivo against Trypanosoma cruzi of (8-hydroxymethylen)-trieicosanyl acetate was evaluated in BALB/c mice during the acute phase of Chagas' disease (15 days after infection). Animals were treated during 15 days at doses of 16.8 and 33.6 µg/g, reduced parasitemia of 77.6 and 64.1% was observed respectively, in comparison with positive control mice (allopurinol 8.5 µg/g) which reduced only 29.7%. Also, amastigote nests in cardiac tissue were significant reduced in treated mice groups. The regression of effect induced after the suppression of the treatment with the compound was evaluated; animals were infected and simultaneously began the treatment with the compound during 20 days (16.8 and 33.6 µg/g). Mice were monitored after the end of the treatment for one more week. A good antitrypanosomal response was observed (66.1 and 68.9% less than untreated mice) during treatment, but 8 days after suspension of treatment, parasitemia level increased, reducing only 58.6 and 56.29 % respectively in treated animals compared with no treated.