American scientists from two universities and the New York State Department of Health investigated the reasons for the mysterious increase in the incidence of legionellosis, or Legionnaires’ disease, an atypical type of pneumonia caused by Legionella bacteria. Experts concluded that clean air is one of the main reasons for the spread of serious respiratory infections. The study was published in the scientific journal magazine Proceedings of the National Academy of Sciences Nexus (PNAS Nexus).
Over the past two decades, the incidence of Legionnaires’ disease in the United States has increased ninefold; It increased from 1,100 cases in 2000 to 10,000 cases in 2018. In Europe and parts of Canada, the number of Legionnaires’ disease infections increased 5-7 times during the same period.
Although major outbreaks of Legionnaires’ disease beginning in 1976 have been linked to air conditioners, commercial ventilation systems, and cooling towers that use fans to remove heat from factories, in the vast majority of cases the underlying source of infection was unknown.
Dirty ventilation systems and cooling towers spread Legionella bacteria over significant distances through the diffusion of water vapor. Microbes settle in water droplets and with them enter the respiratory tract of people.
Researchers examined humidity, temperature, precipitation and ultraviolet radiation in New York state from 1992 to 2019, but none of the parameters could explain the increase in Legionnaires’ disease.
Scientists then turned their attention to the decreasing sulfur dioxide (SO2) In the air. It turns out that the purification of the atmosphere is strangely associated with an increase in the number of lung infections.
Sulfur dioxide is formed when fossil fuels are burned. As modeling shows, when mixed with water, this compound turns into sulfuric acid, creating an unfavorable environment for bacteria.
SO concentration over 20 years, as shown by repeated analysis2 New York’s weather dropped 10 times; almost as much as cases of legionellosis are increasing.
Scientists noted that strategies should be developed to combat bacteria that will keep the atmosphere clean.
happened before knownLegionella disease has reached Warsaw.