Over 600 fish are dead at the Alexandria Zoo after a highly contagious bacterial infection called Columnaris disease spread around the ponds.

The spread of the disease can be associated with the summer heat, which brought the temperature of the ponds to over 80 degrees and the recent rain didn't help either.

Fish are very susceptible to the disease and the chances increase after they have been exposed to an environmental stress, such as when the temperature of the water rises to the upper level of their preferred body temperature.

Zoo keepers noticed the first few fish died on August 6th, and within 48 hours, the Zoo lost all of it's koi and carp population.