Some 12 million Filipinos are reportedly at risk of contracting schistosomiasis (also called bilharzia or snail fever). The tropical disease is endemic to 12 regions in 28 provinces, with 6.8 million people already exposed to the parasite in the country. The highest rate of infection in the Philippines is among those between the ages of five and 15 with a mortality rate of 1.8 percent among untreated patients. While the disease is primarily prevalent in poor provinces, regions, and neighborhoods, any person who comes into contact with contaminated water sources is at risk of contracting the parasite.
Schistosomiasis is an acute and chronic disease caused by parasitic worms. People become infected when larval forms of the parasite - released by freshwater snails - penetrate the skin during contact with infested water. The disease symptoms include bloody urination, abdominal pain, and bloody diarrhea. Transmission occurs when people suffering from schistosomiasis contaminate freshwater sources with their excreta containing parasite eggs which hatch in water. Treatment is available.
The United States Centers for Disease Control (CDC) previously categorized this disease as the most deadly neglected tropical disease (NTD). The World Health Organization (WHO) has said that based on estimates, 218 million people required preventive treatment for schistosomiasis worldwide while more than 66.5 million people were reported to have been treated for the disease in 2015.
Individuals in the Philippines are advised to drink only bottled or purified water, to avoid bathing in bodies of fresh water (lakes, ponds, etc.), and to seek medical attention if presenting the above symptoms.