Introduction
First, they suspected the food prepared for the birthday party to be the cause of the outbreak. It turned out that it was a waterborne disease, a norovirus. Waterborne disease can easily affect children who come in contact with the contaminated water. The swim club manager seemed not very much cooperative during the initial outbreak; but the VHD investigators needed the cooperation of the swim club manager in identifying the real cause of the outbreak. Later, the manager told them that other persons not invited to the February 1 birthday party (members of an infant-mother swim class) got sick ...
