The usefulness of systematic serological screening of congenital to x op las mo sis and Chagas' disease in our country isdiscussed on the basis of 855 cases, which had been studied in three places of Chile (Santiago, Vicuna and Ovalle).Prevalence of maternal toxoplasmosis reaches 35% in Santiago, 29% in Vicuna and 26% in Ovalle. High liters,indicating early infection of the mother, were found in one case, but congenital toxoplasmosis was not considered inher child because his serological tests became finally negative. Prevention of congenital toxoplasmosis by screeningof women during pregnancy (at a great scale) would be far too expansive, technically difficult and of doubtfulusefulness in our country. Instead, early recognition of the infection by serological examination of suspectednewborns is recommended, Chagas' disease was demonstrated in 4 of the 855 cases, three of them being ofcongenital origin. Prevalence of maternal infection was low in Sa'ntiago (2.7 %); but congenital Chagas' disease couldbe detected in 2 out of 10 infants born to serologicaJly positive mothers. However, in the high endemic areas, whereT. cruzi-infect ion reaches 11.8% (Vicuna) and 17.9%(0valle), only one congenital infection was demonstrated in atotal of 61 newborns considered to be a risk. Additional information (by systematic screening of mothers andnewborns in areas of low and high endemicy) is needed in order to clarify the regional differences observed in thepresent study. A surveillance program for congenital Chagas' disease is considered to be technically feasible in Chile.These studies would be restricted to endemic zones, the number of cases which are at risk for congenital infectionwould be manageable (2% to 20% of the total populations studied) and detection of these cases would be obtainedby serological examination of one sample per case. The strategies for studying both congenital infections are given indetail.(Key words: American trypanosomiasis. Chagas' disease. Congenital. Maternal. Serological screening. Toxoplasmagondii. Toxoplasmosis. Transplacental transmission. Trypanosoma cruzi. Trypanosomiasis, American. Epidemiology.Prevention. Follow-up).

Valor diagnostico de la inmunofluorescencia indirecta con anti-IgM para

Congenital transmision of trypanosoma cruzi402 none selected samples of cord sera were studied for Chagas disease by the indirect inmunofluorescent antibody test (IFAT).Positive results were obtained in 11 cases (2,7%).Demonstration of trypomastigotes in the peripheral blood was achieved (by microscopic examination and xenodiagnosis) in two of the eleven newboms submitted to examination.The results suggest that congenital transmission of T. cruzi may ocurre more often than generally accepted.If so, systematic screening for Chagas' disease in newborn infants will prove of great value in detecting suhclinical infections.As shown in this study, early diagnosis and treatment is of essential importance in these cases.

Determination of inmunoglobuline M in 129 normal newborns in Santiago.Cuantitative determination of total IgM, by the radial inmunodifrusion technique, was performed in 129 cord sera from full-term, normal infants in Santiago.The results obtained varied in amounts from 0 to 138 mgs %.A statistical analysis, covering 80% of the sample, gave a P 10 of 3mgs%andaPc )0 of36mgs%, with a mean value of 11 mgs%.Acoording to these results, 30 mgs% is suggested to be considered as cut off for elevated IgM values in cord sera in this population group.Cuantitation of cord serum IgM is of considerable value as a screening method to detect newborns who are at risk for interuterine infection; however, additional, specific technique should be employed to establish a definitive diagnosis.

Duocoxin, nicrazine and amprol plus showed no therapeutic effect in 50 mice each of which was infected with 25,000 organisms of a virulent Toxoplasma strain.

The effectiveness of five treatment regimens was compared to mice during acute and late infection with Toxoplasma gondii. Parasitic cure rates, as judged by failure of brain tissue from surviving mice to produce infection when inoculated into clean mice, were as follows: pyrimethamine + sulfamethoxypyridazine, 92%; clindamycin + sulfamethoxypyridazine, 75%; spiramycin + sulfamethoxypyridazine, 16.7%; trimethoprim + sulfamethoxypryridazine alone, 0%. Pyrimethamine + sulfamethoxypyridazine was the most effective combination against acute toxoplasmosis in mice.