Sack R B, Santosham M, Froehlich J L, Medina C, Orskov F, Orskov I
Am J Trop Med Hyg. 1984 May;33(3):460-6. doi: 10.4269/ajtmh.1984.33.460.
Daily doxycycline (DX), known to be effective prophylaxis against travelers' diarrhea (TD) in areas of the world where enterotoxigenic Escherichia coli (ETEC) are sensitive to the drug, has not been extensively studied in geographic areas where antibiotic resistance is common. Therefore we studied 44 U.S. Peace Corps Volunteers during their first 5 weeks in Honduras, which is such an area. During the first 3 weeks, volunteers took daily either 100 mg DX or placebo (PL) in a double-blind, randomized fashion. All 22 taking PL developed TD during the first 3 weeks, compared to 7 of 22 (32%) taking DX (P less than 0.001; 68% protection). ETEC were isolated from 39% of episodes of TD. From the PL group, ETEC from 7 of 13 stool samples (54%) were resistant to DX, whereas from the DX group, ETEC from 10 of 11 stool samples were resistant (P less than 0.05). TD that developed in persons taking DX was also found to be less severe, as judged by length of illness (P less than 0.01) and frequency of stools (P less than 0.05). This study demonstrates that DX 1) significantly prevents TD even in areas where antibiotic resistance is common, although it does not prevent TD caused by docycycline -resistant ETEC, and 2) significantly diminishes the severity of illness.
已知每日服用强力霉素（DX）在产肠毒素大肠杆菌（ETEC）对该药敏感的世界某些地区可有效预防旅行者腹泻（TD），但在抗生素耐药性普遍存在的地理区域尚未进行广泛研究。因此，我们对44名美国和平队志愿者在洪都拉斯的头5周进行了研究，洪都拉斯就是这样一个地区。在头3周，志愿者以双盲、随机方式每日服用100毫克DX或安慰剂（PL）。所有22名服用PL的志愿者在头3周内都患上了TD，相比之下，22名服用DX的志愿者中有7名（32%）患病（P小于0.001；保护率68%）。39%的TD病例分离出了ETEC。在PL组中，13份粪便样本中的7份（54%）的ETEC对DX耐药，而在DX组中，11份粪便样本中的10份的ETEC耐药（P小于0.05）。从患病时间（P小于0.01）和排便频率（P小于0.05）判断，服用DX者患的TD也较轻。这项研究表明，DX 1）即使在抗生素耐药性普遍存在的地区也能显著预防TD，尽管它不能预防由耐强力霉素的ETEC引起的TD，2）能显著减轻疾病的严重程度。
