Sera from healthy Peruvians between the ages of 10 and 50 years (but mostly between 20 and 25 years) were tested for toxoplasma antibodies by the indirect fluorescent antibody method. The majority of the persons were blood donors or students from towns in different regions.

Positive reactors at a titre of 1 in 16 were found in 42% of 370 persons in Lima (coastal region), 9% of 144 in the Andean region and 47% of 283 in the jungle region. In the Andes all the reactors had titres of only 1 in 16, compared with the coastal region where 68 % of the positive reactors had such a low titre and the jungle region where only 45% had a similar low titre. High titres (1 in 512 or more) were found only in the last group. The prevalence was the same in males and females. The lowest prevalence and the lowest titres were found in the dry or arid Andes, the highest in the humid jungle. No information on the cat populations is given. The findings are compared with those of other surveys. J. K. A. Beverley.