Reopened Colleges Discover Well being Dangers in Water After Covid-19 Lockdowns

The CDC has issued guidelines for reopening businesses and buildings after the coronavirus lockdown. An agency spokeswoman said her guidelines are “applicable to all types of buildings,” including schools. But the vagueness of many guidelines means, according to Dr. Whelton that schools can take as much or as little general preventive action and claim compliance.


July 8, 2021, 6:10 p.m. ET

The common way to protect yourself from Legionella growth is through a process known as purging. By introducing fresh water into the system, a small dose of chlorine remains in the system, which limits the ability of the bacteria to multiply. However, flushing must be done regularly and for all outlets. That means running every tap, shower and toilet.

One of the Ohio schools that found the bacterium, Englewood Elementary in the Northmont City Schools District outside of Dayton, began flushing its system in July. When a water management company discovered Legionella last week, they shut off all of the water in the building and sent high levels of chlorine through the system. A spokeswoman for the county said the water will continue to be tested to ensure it is safe.

The only way to tell if the conditioner is effective is to test the water. A single flush will not eliminate Legionella if they are present. Milton Union High School in Ohio began testing their water in late July. They found that the chlorine level had dropped to zero after 72 hours. They flushed again and when they tested 24 hours later it was back to zero. They tested the water and found legionella.

Caitlin Proctor, a postdoctoral fellow at Purdue who studied Legionella during the lockdown, said that despite the use of chlorine, the bacteria ‘s biofilms can protect some of them from completely disappearing. “They can reproduce again as soon as the disinfectant has evaporated.”

Officials from the suburban Fox Chapel Area school district, who also discovered the bacteria in several schools, said in an email to parents that they were sending high-temperature water through the system. This process, known as thermal shock, has been suggested by the county health authorities as another means of killing the bacteria. However, some industry groups question the effectiveness of thermal shocks in stopping Legionella.

Some schools do not have the budget to test for Legionella and other water-related risks. But even the schools that do so encounter a lack of authoritative advice. For example, many test their water immediately after rinsing. Since the water is fresh, the legionella will not be visible, which makes the test ineffective.