MIAMI BEACH (CBS4) - A health problem on Miami Beach seems to be spreading. Officials say more stray cats are using the sand as a litter box leading to an increased number of hookworms. Six people have now been treated for hookworms believed to have come from a stretch of Miami Beach where there are a large number of feral cats.

Members of the Miami-Dade Department of Health were back on the beach Friday, documenting potential evidence of the hookworm outbreak, particularly along the sandy stretch west of the dunes in the 60th Street area. They found sample, after sample, after sample of fresh cat feces, cat food and hundreds of cats hidden in the mangroves. That parasite can be carried in cat feces and due to the large stray cat population, officials believe this is the source of the problem.

Paul Sylvestre of the Miami-Dade Department of Health told CBS4's Chief I-Team Investigator Michele Gillen that it's important for beachgoers to use a towel or blanket when laying on the sand and wear shoes or sandals on the beach.

Residents in the area had heard of the hookworm outbreak but couldn't believe it was in their own backyard.

Michele Gillen has been investigating what's in the South Florida sand for months. Click here to read and see more and be sure to tune in Sunday, Nov. 14 for her in-depth report on an I-Team Special at 6:30 p.m. on CBS4.

CBS4's Michele Gillen contributed to this report.

(© MMX, CBS Broadcasting Inc. All Rights Reserved.)