Fenwick A, Figenschou B H
Bull World Health Organ. 1972;47(5):567-72.
In an attempt to justify future snail control on an irrigated sugar estate in Tanzania, the effects of Schistosoma mansoni infection on the productivity of apparently healthy cane cutters were investigated. The bonus earnings of cane cutters who were found to be infected with S. mansoni were compared, retrospectively, with earnings of uninfected cane cutters during the years 1968-69. For one 6-month period a more detailed study was made to correlate bonus earnings with actual output in tons of cane cut. It was found that in the four 6-month periods the mean bonus earnings of the uninfected cane cutters exceeded the mean bonus earnings of the infected men by 11.0%, 11.4%, 6.0%, and 13.7%, respectively. In all except the third period these differences were statistically significant. After treatment for S. mansoni infection, the workers were able to improve their earnings relative to both infected and uninfected workers. In a more detailed study of some of the workers during the third 6-month period, it was discovered that a 4% difference in bonus earnings represented a 1% difference in output. Taking into account the variations of bonus earnings it was estimated that the overall difference in productivity between infected and uninfected workers was 3-5%.
为了证明在坦桑尼亚一个灌溉甘蔗种植园未来进行蜗牛控制的合理性，研究了曼氏血吸虫感染对表面健康的甘蔗砍伐工人生产力的影响。回顾性地比较了1968 - 1969年期间被发现感染曼氏血吸虫的甘蔗砍伐工人与未感染工人的奖金收入。在一个为期6个月的时间段内，进行了更详细的研究，以将奖金收入与实际砍伐甘蔗的吨数产量相关联。结果发现，在四个6个月的时间段里，未感染甘蔗砍伐工人的平均奖金收入分别比感染工人的平均奖金收入高出11.0%、11.4%、6.0%和13.7%。除第三个时间段外，所有这些差异在统计学上均具有显著性。在接受曼氏血吸虫感染治疗后，这些工人相对于感染和未感染的工人都能够提高他们的收入。在对第三个6个月期间的一些工人进行更详细的研究中，发现奖金收入4%的差异代表产量1%的差异。考虑到奖金收入的变化，估计感染和未感染工人之间的总体生产力差异为3 - 5%。
