activity. In 2009, reporting to the WBDOSS transitioned from a paper form to the electronic National Outbreak Reporting System (NORS). Annual or biennial surveillance reports of the data collected by the WBDOSS have been published in CDC reports from 1971 to 1984; since 1985, surveillance data have been published in the Morbidity and Mortality Weekly Report (MMWR). WBDOSS and the public health community work together to look into the causes of contaminated water leading to waterborne disease outbreaks and maintaining those outbreaks. They do so by having the public health community investigating the outbreaks and WBDOSS receiving the reports. Society and culture Socioeconomic impact Waterborne diseases can have a significant impact on the economy. People who are infected by a waterborne disease are usually confronted with related healthcare costs. This is especially the case in developing countries. On average, a family spends about 10% of the monthly households income per person infected. History Waterborne diseases were once wrongly explained by the miasma theory, the theory that bad air causes the spread of diseases. However, people started to find a correlation between water quality and waterborne diseases, which led to different water purification methods, such as sand filtering and chlorinating their drinking water. Founders of microscopy, Antonie van Leeuwenhoek and Robert Hooke, used the newly invented microscope to observe for the first time small material particles that were suspended in the water, laying the groundwork for the future understanding of waterborne pathogens and waterborne diseases. See also Airborne disease Food microbiology List of diseases caused by water pollution Neglected tropical diseases Public health Vector (epidemiology) Water quality Zoonosis References External links Water-related Diseases, Contaminants, and Injuries Listing of water-related diseases, contaminants and injuries with alphabetical index, listing by type of disease (bacterial, parasitic, etc.) and listing by symptoms caused (diarrhea, skin rash, and many more ) including links to other resources (CDC's Healthy Water site) World Health Organization (WHO) "Water-Related Diseases" Drinking water Sanitation Environmental health