Resumen

HERNANDEZ-CHAVARRIA, Francisco; CHAVES, Fernando  y  FREER, Enrique. Clostridium Tetani, tétanos y su frecuencia en Costa Rica. Rev. costarric. cienc. méd [online]. 2000, vol.21, n.3-4, pp.191-202. ISSN 0253-2948.

Clostridium tetani is a cosmopolitan and normal inhabitant of the soil and marine sediments, and it is often isolated from intestines of animals. This agent is a spore forming, anaerobic, Gram positive bacilli, that produce the tetanospasmine, a potent neurotoxin responsible of the clinical entity, know as tetanus. The bacteria is isolated from soil samples at virtually any location, with a frequency usually higher than 30%, as described for Costa Rica. C. tetani, as other species of the genus Clostridium, exhibits the swarming phenomenon, which consists in a morphological and physiological modification, that conduces to hyper-flagellated, giant cells that actively move on solid culture medium, forming a growth film. In Costa Rica, for the period from 1916 to 1970 there were between 365 to 200 annual mortal cases. Then, fatal cases decreased to less than 20 from 1970 to 1980. Since 1980 there were lesss than three fatal cases by year. The sharp reduction of the number of cases was the effect of the two intense vaccination campaigns against tetanus; the first in 1951 (DPT) and the second in 1971 using a toxoid vaccine. However if the figures are adjusted by death rates /100 000 persons, the resulted negative slope of the curve showed a progressive reduction tendency that was more evident from 1926. We propose that comunitary education, sanitation development, improved health services at deliver time, proper management of skin injuries, among other factors are related to the mortality reduction by tetanus.

Palabras clave : tetanus; soil isolation; mortality rates.