People are often not aware of the disastrous consequences of dumping waste and wastewater into the waterways and oceans of developing countries. Even in many parts of the country, there is no infrastructure to provide treated water and ensure that wastewater fields are adequate and do not infiltrate the water table used by the community. Old sewage systems carry everything residents leave in toilets, such as pharmaceuticals and personal care products, as well as human waste. The same system also has rainwater that washes sidewalks, streets, and gutters, containing chemicals, pesticides, fertilizers, and garbage.
Diseases associated with polluted water and vector transmission (Insects)
Contaminated water may be a factor in vector diseases, i.e., diseases conveyed by mosquitoes or other insects that find favorable breeding conditions in dirty water and reproduce more quickly in it. These insects host the parasites and cause numerous dangerous diseases. The major vector-borne illnesses include:
● Schistosomiasis: is more common and is a parasite known as blood fluke that hatches from eggs into feces or urine from infected individuals who defecate or urinate in freshwater in the tropics. As the eggs hatch, the parasite grows and multiplies in the snail. When they leave the snails, parasites may penetrate the skin of people wading, swimming, or bathing in contaminated water. It can also spread via skin-to-skin contact or by cutting or scratching. The disease affects approximately 200 million people worldwide and is most commonly found in tropical communities with poor sanitation. The parasitic roundworm occurs within the blood vessels of the human host, where the female produces eggs. Eggs typically go to the intestines, liver, or bladder. The body’s response to the eggs, not the worms themselves, causes a host of problems, including anemia, malnutrition, learning problems, and, over time, damage to the bowel, liver, bladder, and even lungs. Eggs are also found in the spinal cord or brain, leading to infection, convulsions, or even paralysis.
● Malaria: is a severe and sometimes fatal illness caused by a parasite that routinely infects a specific mosquito that feeds humans. People who contract malaria are usually very sick with high fevers, shivers, and influenza-like diseases. Four types of malaria parasites infect people: Plasmodium falciparum, P. vivax, P. ovale, and P. malariae.
● Lymphatic filariasis: is a parasitic disease caused by microscopic worms that breed in contaminated water similar to thread. Adult worms are found only in the lymphatic system of man. Lymph filariasis is transmitted from person to person through mosquitoes. People with this disease may have lymphoedema and elephantiasis, and in men, this disease causes swelling in the scrotum, called a hydrocele.
● Dengue fever: is a disease caused by a family of Aedes mosquito-borne viruses. Symptoms of dengue fever include severe joint and muscular pain, swollen lymph nodes, headache, fever, exhaustion, and rashes. The dengue virus is widespread in the tropics and subtropical regions.
● Yellow fever: is an Acute virus hemorrhagic disease transmitted by infected mosquitoes. The “yellow” in the name refers to icterus which affects certain patients. Its symptoms include fever, headache, jaundice, muscular pain, nausea, vomiting, and tiredness.