of clean water (51% service coverage, 307 L) allowed
the population to maintain individual hygiene and food
safety practices, which resulted in a decrease in the
incidence of typhoid fever and the second decrease in
the fatality rate. In 1971, the fatality rate was already
maintained at the 1% rate by providing proper medical
services, but the water service coverage continuously
increased. Therefore, an adequate amount of clean water
was the primary and most important factor in preventing
typhoid fever.