The percentage of acute cases of toxoplasmosis found in this study (5.9%) considering only PCR positive cases (1.8%) plus IgM, PCR positive cases (4.1%) are lower than the 8.3% found by Galván et al. [8] in Guadalajara, Mexico, considering only IgM antibodies. The gene discussed is CD40LG; the disease is toxoplasmosis.