A resident of California lost their life after exposure to water contaminated with fatal bacteria.
They were among over a dozen individuals who contracted Legionnaires’ disease in Napa County, located approximately one hour northeast of San Francisco, due to a deteriorating water system.
The outbreak occurred in July 2022, but the Centers for Disease Control and Prevention (CDC) only disclosed it in a report today.
CDC investigators linked the cluster of cases to the improper maintenance of multiple water plant cooling towers. This negligence permitted bacteria to accumulate and flow through pipes into residential properties and faucets, potentially exposing individuals to the pathogens through inhalation of water droplets or consumption of water from their residences.
Legionnaires’ disease is a severe form of pneumonia predominantly caused by the Legionella bacteria, which flourishes in the water supply of large structures.
A mortality rate of approximately 10 per cent is attributed to complications arising from Legionnaires’ disease; however, individuals with compromised immune systems may experience a fatality rate as high as 30 per cent.
Napa’s Legionnaires’ Challenge
It is particularly problematic in temperate climates, where the heat facilitates its reproduction, such as in Napa, where summer temperatures can reach 80 degrees.
Fourteen confirmed cases of the disease were reported by Napa County Public Health (NCPH), with an additional three points being suspected.
Ten confirmed patients required intensive care unit admission, while five were mechanically ventilated.
In total, one fatality and sixteen cases and suspected cases necessitated hospitalisation.
NCPH was notified on July 11 and 12, 2022, of three positive disease tests conducted in Napa, the renowned wine country.
Between July 11 and August 15, 2022, additional investigations uncovered eleven confirmed cases and three suspected cases of Legionnaires’ disease. California typically experiences one to two issues annually.
Two of the 14 patients had visited downtown Napa, and one worked there.
In collaboration with the California Department of Public Health (CDPH) and the CDC, the health agency could concentrate its investigation on facilities within a limited geographical area due to the proximity and scheduling of the cases.
Public health professionals linked the incident to an environmental cause by sequencing water and positive test results.
High-Risk Zone and Facility Inspections
Authorities established a ‘high risk’ zone in the Napa region. This zone was defined as the vicinity of a concentration of patients’ residences within a one-mile radius.
Seven of the eight assessed facilities were situated within the high-risk radius.
Five of seven locations tested positive for Legionella, with cooling towers at all facilities.
Inspections, records, and samples of the facilities revealed a deficiency in cooling tower maintenance. Numerous towers needed more chlorine or contained adequate chlorine concentrations. This disinfectant eliminates bacteria, viruses, and parasites in water.
According to officials, this occurred because the cleaner was improperly added to the water towers. It happened due to a system malfunction, such as clogged pipelines preventing the cleaning solution from entering the building.
After thoroughly examining the results, public health authorities notified nearby healthcare providers. They instructed them to conduct Legionella testing on patients presenting with pneumonia or comparable symptoms.
Additionally, the public was issued a warning that detailed the circumstances and urged individuals experiencing symptoms to seek medical attention.
Officials also notified positive facilities and issued one court order to close a noncompliant location.
Legionnaires’ disease is transmitted via showerheads, air conditioning units, and faucet water droplets; the bacteria can cause pneumonia, a potentially fatal illness that is currently on the rise among children in the United States.
Symptoms and Diagnostic Measures
Cough, difficulty breathing, fever, muscle aches, headaches, and chest discomfort are among the symptoms.
Health and safety regulations stipulate that hot water supplies must be maintained at a minimum temperature of 122 degrees Fahrenheit. This is to inhibit bacterial growth since the bacteria cannot survive at this elevated temperature.
The minimum temperature for cold water is 68 degrees Fahrenheit.
Legionnaires’ disease can be diagnosed through urine or blood tests. These tests detect the presence of Pontiac fever, a moderate influenza-like illness induced by Legionella bacteria exposure. Despite this, a negative test result does not preclude the possibility that an individual is infected.
Legionnaires’ disease necessitates antibiotic treatment following a diagnosis.
According to the most recent data from the CDC, 8,900 cases of the disease were reported in 2019. However, the actual number is likely higher because many cases go undiagnosed.
