In our work we found that resistance was associated with a high parasite-specific IgA titres present in saliva since the beginning of the infection, and remained constant during the experiment, while susceptible animals had low parasite-specific IgA levels at the beginning of the study and presented increased IgA levels only at 3 weeks after infection, indicating that potency and duration of the elicited adaptive immunity, and in particular, IgA antibody levels, are key to assure resistance and parasite clearance. The gene discussed is CD79A; the disease is infection.