To the Editor.
—The article by Drs Nussenblatt and Belfort1 challenges the established concept that ocular toxoplasmosis is usually a result of congenitally acquired infection. The authors base their postulate on data from various studies performed in areas in Brazil known for the high prevalence of toxoplasmosis. The data include reports of ocular toxoplasmosis in nontwin siblings, transient high IgM titer in some adults with ocular toxoplasmosis, a lower disease prevalence in infants, and increasing incidence with age.The authors' conclusions appear to be convincing. However, in this population with continuous exposure to toxoplasmosis, other possibilities that may have contributed to the above findings should also be considered or explored. One is that of reinfection. Can reinfection occur during subsequent pregnancies and result in congenital toxoplasmosis in the siblings? Coutinho et al2 found evidence of reinfection in other regions of Brazil based on both clinical and serological findings.
Abter EIM, Rode AM. Ocular Toxoplasmosis. JAMA. 1994;272(5):356. doi:10.1001/jama.1994.03520050034025