Invasive hammerhead worms are spreading in Texas, and have been spotted in Houston, Dallas, Austin and toward the coast.

Tapeworms have a three-stage lifecycle: an egg, an immature stage called a larva, and an adult stage at which the worm can produce more eggs. ... Preventing Tapeworms in Humans.

Screwworm parasites primarily infect livestock, but human cases have risen in Central America after the pests escaped ...