Clostridium Welchii

CLOSTRIDRIUM WELCHII

  • This organism is normally an intestinal inhabitant . It is a spore-forming organism, which survives for a considerably longer time in water than the coliform bacilli, and usually resists chlorination.
  • Its presence in water indicates that faecal pollution has occurred, and the finding of Cl.welchii in the absence of members of the coliform group indicates that the contamination is not of very recent date.
  • The chief value of looking for this organism would seem to lie in the detection of remote or intermittent pollution in surface or shallow water supplies , such as those from a pond or a well.
  • Supplies from these sources are commonly used on farms and by small rural communities and their frequent examination by the coliform test is seldom, if ever , practicable.
  • An occasional examination for coliform bacilli might in any case yield misleading results, since these organisms might have died out since the last access of pollution. In circumstances such as those mentioned, then, the demonstration of Cl. welchii will show that water is subject to contamination, and will indicate the necessity of taking steps to eliminate the source of pollution, or otherwise prevent it gaining access to the water. 
Last modified: Wednesday, 9 March 2011, 9:10 AM