Fernández, R.A.*(1), Ciccarelli, A.S.(1), P. de Centorbi, O.N.(2), Centorbi, H.(2), Rosetti, F.A.(3), de Jong, L.I.T.(1), and Demo, N.(2).
(1)Cát. Microbiología, FCMédicas, UNCuyo, Mendoza, (2)Cát. Bacteriologéa, FQBF, UNSan Luis, San Luis, and (3)Serv. Bacteriol. Sanitaria, Instituto Carlos G. Malbrán, Buenos Aires, Argentina.

Infant botulism, first recognized in 1976, occurs in infant between 1 week and 12 months of age and results from the absorption of botulinal toxin produced by clostridia that colonize the intestinal tract. The majority of cases published comes from the USA. In Argentina, the first case was described in 1982. Between 1982 and 1997 we reported 145 cases.
Fecal samples, and serum when available, were obtained after admission. Serum and fecal specimens were tested for botulinal toxin, and the fecal samples were also cultured for toxigenic organism. In all pacients, the diagnosis was established by the identification of botulinal toxin and the organism in feces. Toxin was found in the serum of 28/46 (60,9%) patient of Mendoza. This is interesting in view of the negative results usually reported in USA.
The geographical distribution of cases is: Mendoza 46 (31,7%), Buenos Aires 45 (31,0%), Neuquén 16 (11,0%), San Luis 13 (9,0%), Río Negro 7 (4,8%), Chubut 4 (2,8%), La Pampa 3 (2,1%), Córdoba 3 (2,1%), San Juan 3 (2,1%), Tierra del Fuego 1 (0,7%), Misiones 1 (0,7%), Salta 1 (0,7%), Santa Fe 1 (0,7%) y Tucumán 1 (0,7%).
The cases included in this report were between 2 and 48 weeks of age (95% with 24 weeks old or younger and only one with 48 weeks). Arithmetical mean: 13,7; median: 12 and mode: 8. Fifty four (37,2%) were baby boys and 38 (26,2%) were baby girls. Sex was not recorded in 53 (36,6%) cases. The seasonal distribution was: 21 june-20 september (winter): 43 (29,7%); 21 september-20 december (spring): 42 (29,0%); 21 december-20 march (summer): 36 (24,8%) and 21 march-20 june (autom): 22 (15,2%). In 2 cases was not available.
The majority of the pacient lived in the suburbs of cities or in rural areas in both cases, associated with environmental factors such as dryness, strong winds an dust. All strains isolated belonged to C. botulinum type A which is consistent with the predominance of this type in Argentina. It is possible that many cases are still occurring unnoticed. Pediatricians having more experience with cases of infant botulism and improved access to diagnosis laboratories may lead to better identification of future cases.