In May, the U.S. Centers for Disease Control and Prevention (CDC) warned that building closures for a period of time could trigger Legionella growth. When the water supply pipe is closed, the flow of tap water will stop and the chlorine and other disinfectants in the water will gradually evaporate. If the tap water is not used for a long time, its temperature can reach 77 to 108 degrees Fahrenheit (25 to 42 degrees Celsius), which is conducive to the growth and reproduction of bacteria. Today Legionella is found in buildings leased by the Centers for Disease Control and prevention.
Image source of CDC office area: Capitol Hill
In a statement, the Centers for Disease Control and Prevention said, despite the corresponding preventive measures, they still found Legionella in several water sources and a cooling tower of the office building, which may lead to human infection with Legionella. For safety reasons, the buildings will continue to be closed until the clean-up is completed.
Chris Edens, an epidemiologist at the U.S. Centers for Disease Control and prevention, said: its not clear whether the new outbreak exacerbates the problem. Generally, state health departments are responsible for monitoring Legionella infection, and there is no national agency to monitor Legionella infection in water sources in buildings.
Legionella is found not only in office buildings, but also in factories, medical centers, schools, restaurants and stadiums, according to the US health website everyday health on July 30.
In mid July, a California Resort Hotel reported that it had tested positive for Legionella in its tap water during the closure period. On July 1, a school employee in Kettering, Ohio, was diagnosed with Legionnaires disease. Subsequently, Legionella was detected in four locations on the campus. In July, the bacteria were also found in buildings on the University of Pennsylvanias West Chester campus. At the end of June, there was also a case of Legionnaires disease at a nursing home in Bloomfield Hills, Michigan.
How harmful is Legionella
Hospitals and clinics need to pay attention to Legionella as people begin to return to work or go out, Edens said. Right now, influenza and the new coronavirus are not the only causes of severe pneumonia, he said Novel coronavirus pneumonia should be tested if people develop pneumonia symptoms. The disease can be treated with antibiotics, which is completely different from influenza or new crown pneumonia.
A color electron microscope image of Legionella: CNN
Many studies have confirmed that most cases of Legionnaires disease are associated with hot and cold water pipeline system, heating system, air conditioning cooling water and shower water. A study published in the journal emerging infectious diseases in July showed that the spread of microbial aerosols caused by toilet flushing can also spread the pathogen.
According to the Centers for Disease Control and prevention, the number of Legionella cases has increased nearly nine times since 2000. The National Academy of science, engineering and medicine (nasem) estimates that 52000 to 70000 Americans are infected with Legionnaires disease every year.
Salmonella infection in nearly 50 states
In addition to Legionella, hundreds of people have been infected with Salmonella in the United States recently. According to the investigation, it may be related to the red onion sold in 50 states and Canada.
Salmonella infection in many parts of the United States may be related to onions contaminated with Salmonella, the Capitol Hill reported on the 3rd. According to the report, the batch of red onions containing Salmonella has been transported to supermarkets and restaurants in 50 states and Canada. Thomson international, based in Bakersfield, California, has recalled all red, white, yellow and sweet onions sold since May 1 on August 2 because of concerns about possible impact on its products.
The food and Drug Administration (FDA) issued a warning on social media
CDC pointed out that people will have diarrhea, fever, abdominal spasm and other symptoms within 6 hours to 6 days after infection with Salmonella. Patients with severe symptoms may also have high fever, headache, fatigue, rash and blood in urine or feces. The CDC warned that people could die from Salmonella infection, which estimates that about 1.35 million people are infected with Salmonella each year in the United States.