Schistosomiasis (bilharziasis) is a major human disease caused by three species of the genus Schistosoma, known collectively as blood flukes. Africa and western Asia (e.g., Iran, Iraq) are endemic centres for S. haematobium; S. mansoni also is found in these areas, as well as inâ¦
How Alcohol Damages Sperm. Alcohol can reduce the quantity of sperm a man produces (his sperm count) and the quality of that sperm. One way in which alcohol does this is by preventing the body from absorbing zinc in the normal way. Zinc is found in high quantities in sperm.
Long term use of marijuana does affect fertility in both men and women. For men, marijuana causes a lower sperm count and smaller volume of seminal fluid, that is about half of the normal amount. However, Marijuana also causes abnormalities in the existing sperm.The problem comes from timing.or men, marijuana causes a lower sperm count and smaller volume of seminal fluid, that is about half of the normal amount. However, Marijuana also causes abnormalities in the existing sperm. The problem comes from timing.