Spatiotemporal variation of human pathogenic bacteria was observed in the surface waters of a monsoonal estuary and these bacteria were also found to be associated with the native fish of two monsoonal estuaries. The temporal variation was in accordance with any monsoonal estuary. Also, the spatial variation in physicochemical parameters and bacterial counts was very evident at any given time. For instance, one sampling location in the estuary consistently had 10³ fold higher bacterial counts than the rest of the locations within the same estuary. Coliforms, Salmonella-like (SmLO) organisms, Shigella-like (SLO) organisms, Vibrio parahaemolyticus-like (VPLO) organisms and Vibrio cholerae-like (VCLO) organisms occurred at many locations, but the abundance of each group varied differently with time at different locations in the estuary. Coliforms, unlike others, showed an increase in abundance from post-monsoon to pre-monsoon season. VCLO were the most abundant amongst all. Not all the pathogenic bacteria were widespread throughout the channel indicative of dominance in spatial variation over seasonal in this estuary. Most of the fish samples showed similar trend of bacterial numbers as that in surrounding waters, except a few. Presence of sewage pollution indicator bacteria in the fish indicated that fish served as reservoirs of these bacteria. Thermal death time of randomly picked fish-associated isolates was 30 min at 80 °C and these could survive freezing temperature for 24 h and produce siderophore which can account for their pathogenic nature. The monsoonal estuaries thus render survival ground of such bacteria.

在季风河口的地表水中观察到人类致病细菌的时空变化，并且还发现这些细菌与两个季风河口的本地鱼类有关。时间变化符合任何季风河口。同样，在任何给定时间，理化参数和细菌数量的空间变化都非常明显。例如，河口中的一个采样位置始终比同一河口中其他位置的细菌计数高10 ³倍。大肠菌群，沙门氏菌（SmLO）生物，志贺氏菌（SLO）生物，副溶血性弧菌（VPLO）生物和霍乱弧菌类（VCLO）生物发生在许多地方，但河口不同地点的每个群体的丰度随时间变化。与其他大肠菌不同，大肠菌群从季风后到季风前季节增加。VCLO是其中最丰富的。并非所有的致病细菌都分布在整个河道中，这表明该河口在整个季节的空间变化占主导地位。除少数鱼类外，大多数鱼类样品的细菌数量趋势与周围水域相似。鱼中存在污水污染指示细菌，表明鱼类是这些细菌的储存库。随机挑选的与鱼类相关的分离株的热死亡时间在80°C下为30分钟，它们可以在冰冻温度下存活24 h，并产生铁载体，这可以解释其致病性。季风河口因此成为这类细菌的生存基础。