ATLANTA – Hospitalizations for three common water-borne diseases cost the healthcare system as much as $539 million annually, according to research recently presented at the International Conference on Emerging Infectious Diseases.

"These cost data highlight that water-related diseases pose not only a physical burden to the thousands of people sickened by them each year, but also a substantial burden in healthcare costs, including direct government payments through Medicare and Medicaid," said Michael Beach of the Centers for Disease Control and Prevention, an author of the study.

There is no data on total healthcare costs associated with all water-borne diseases. However, using data from a large insurance claims database between 2004 and 2007, Beach and his colleagues estimated the hospitalization cost of three common water-borne diseases in the United States – Legionnaires' disease, cryptosporidiosis and giardiasis.

For each case, they calculated the cost paid by the insurer, the out-of-pocket cost to the patient and the total amount paid.

Total estimated costs for hospitalization for the three diseases was $154 million to $539 million, including $44 million to $147 million in direct government payments for Medicare and Medicaid. Estimated annual costs for the individual diseases were $16 million to $63 million for giardiasis, $37 million to $145 million for cryptosporidiosis and $101 million to $321 million for Legionnaires' disease.

Inpatient hospitalization costs per case averaged more than $34,000 for Legionnaires' disease, approximately $9,000 for giardiasis and more than $21,000 for cryptosporidiosis.

"These infections can cause severe illness that often result in hospital stays of more than a week, which can quickly drive up healthcare costs," Beach said.

The study suggests that modest investments in preventing these diseases could lead to reduced rates of infection and significant healthcare cost savings. Examples of possible low-cost interventions include public education campaigns, appropriate maintenance of building water systems and regular inspection of pools and other recreational water facilities.