Schistosomiasis, also known as bilharzia (bill-HAR-zi-a), is a disease caused by parasitic worms. Infection with Schistosoma mansoni, S. haematobium, and S. japonicum causes illness in humans.Although schistosomiasis is not found in the United States, more than 200 million people are infected worldwide.chistosomiasis, also known as bilharzia (bill-HAR-zi-a), is a disease caused by parasitic worms. Infection with Schistosoma mansoni, S. haematobium, and S. japonicum causes illness in humans.
Part 2: How do Dry Snorkels Work? Dry snorkels have a mechanism at the top of the tube that closes when you submerge under water. It also has a covering at the top to prevent surface water from splashing into the top of tube. The dry snorkel has a valve/hinge mechanism at the top. When you submerge underwater, accidentally or purposely, the hinge reacts via a float mechanism and closes onto the top of the tube and seals it which prevents water from filling the tube.
What are the differences between snorkeling, free diving, skin diving, Scuba diving is fairly easy to figure out what is: strap a tank on your back and breathe from it under water, and by default, youâre scuba diving. But remove the tank and things get a lot murkier, and often, terms like snorkeling, free diving, and skin diving is used interchangeably. But there are differences, and each has its advantages, and we as scuba divers can learn from them.