Burr D H, Sugiyama H
Infect Immun. 1982 Apr;36(1):103-6. doi: 10.1128/iai.36.1.103-106.1982.
The relationship between the indigenous intestinal microflora of adults and their resistance to the enteric botulinum infection of infant botulism was studied. Orogastric challenges of 10(5) type A Clostridium botulinum spores were given to adult mice whose gut flora had been altered by feedings of a mixture of erythromycin and kanamycin sulfate. From 80 to 100% of mice became infected when challenged 15 to 60 h after antibiotic administration. The mean infective dose of 2 X 10(4) spores per mouse for challenges given 23 h after antibiotic administration contrasted with the failure of 10(6) spores to infect control mice. Botulinum-colonized mice remained asymptomatic, although colonization lasted up to 5 days, and total botulinum toxin in the gut on days 3 and 4 postchallenge averaged 3,400 and 2,200 mouse intraperitoneal mean lethal doses. The mean infective dose for inocula placed in the colon of antibiotic-treated mice was 10(3) spores per mouse, and C. botulinum multiplied in the cecum as well as in the colon.
研究了成年小鼠肠道内原生微生物群落与其对婴儿肉毒中毒肠道肉毒杆菌感染抵抗力之间的关系。给肠道菌群因喂食红霉素和硫酸卡那霉素混合物而改变的成年小鼠经口胃途径接种10⁵个A型肉毒杆菌孢子。在抗生素给药后15至60小时进行攻击时，80%至100%的小鼠被感染。抗生素给药后23小时进行攻击时，每只小鼠的平均感染剂量为2×10⁴个孢子，相比之下，10⁶个孢子未能感染对照小鼠。肉毒杆菌定殖的小鼠没有出现症状，尽管定殖持续长达5天，攻击后第3天和第4天肠道内肉毒杆菌毒素总量平均为3400和2200个小鼠腹腔平均致死剂量。置于抗生素处理小鼠结肠内接种物的平均感染剂量为每只小鼠10³个孢子，肉毒杆菌在盲肠和结肠中均有繁殖。
