Many scientists claim that there is evidence that coronavirus in small particles in the air can infect humans, so they called on the World Health Organization (WHO) to change its recommendations.
The WHO states that coronavirus is primarily spread from person to person with drops, from the nose and mouth of an infected person when sneezing, coughing or talking. In an open WHO letter, 239 scientists from 32 countries presented evidence that smaller particles could infect humans. They plan to publish their letter in a scientific journal next week, writes the New York Times.
Even in its latest correction regarding coronavirus, the WHO states that the transmission of the virus by air is possible only after medical procedures that produce aerosols or drops of less than five microns, and that proper ventilation and N95 masks can help in those situations. It doesn’t matter if the coronavirus is transmitted by larger particles after sneezing or by smaller particles created by breathing, the coronavirus is transmitted through the air and can infect people when they inhale it, scientists say.
However, the WHO states that the evidence for such a virus transmission, ie airborne transmission, is not convincing. “In recent months, we have repeatedly stated that we believe air transfer is possible, but there is no solid evidence of that,” said Bennett Allegranci, director of the WHO’s Infection Prevention and Control Program, adding that discussions were under way. In early April, a group of 36 air quality experts and aerosols called on the WHO to consider growing evidence of airborne coronavirus transmission.
The agency reacted quickly and invited Dr. Lidija Moravska, group leader and longtime WHO consultant. Dr. Moravska and others have pointed to several cases that indicate the transmission of the virus through the air, especially in poorly ventilated and crowded places. They said the WHO makes an artificial distinction between aerosols and larger droplets, although infected people produce both. “Since 1946. We know that coughing and talking create aerosols, “said Dr. Linzi Marr, an expert in transmitting the virus by air from Virginia Tech.
Scientists have failed to grow coronavirus from aerosols in the laboratory. But that doesn’t mean aerosols aren’t contagious, said Dr. Marr, adding: “Most of the samples in these experiments come from hospital rooms with good airflow that would dilute the level of the virus.” In most facilities, she said, “airflow is usually much lower, allowing the virus to accumulate in the air, which poses a greater risk.” Dr. Marr and other experts said that coronavirus was most effective when people were in long-term contact, especially indoors, close to each other, which is what scientists call the transmission of the infection by small particles (aerosols).