NUcheckt assesses messages for their reliability. According to multiple readers, a German virologist has said that researchers have shown that 50 percent of corona infections are from aerosols. This is not the case.

Several readers wrote this week on NUjij that the German virologist Christian Drosten said on May 26 that it has been proven that half of the infections with the coronavirus occurred through very small droplets - so-called aerosols - emitted by infected persons. Aerosols, unlike larger droplets, can float in the air for a longer period of time.

Drosten expects aerosols to play an important role in the spread of the coronavirus. However, he did not say that it has been proven that half of the coronavirus infections were aerosolized.

“Listen to the scientific podcast 26 May of Prof Dr Drosten. He says that research shows that 50 percent, pay attention to 50 percent, of the infections caused by aerosols inside. ” NOW you reader

Where is it from?

Christian Drosten is a virologist at the University Hospital Charité in Berlin. Twice a week he records a podcast with the German radio station NDR, in which he is interviewed by a science journalist.

Monday's podcast discussed aerosols, and their possible role in the spread of the coronavirus. Drosten says in this podcast that several studies showed that coronavirus infections mainly occur indoors, which according to Drosten indicates that aerosols play a role in the spread of the coronavirus. After all, aerosols can occur in the air in relatively high concentrations.

See also: NUchecks: UvA study no evidence for corona hazard aerosols

In addition, Drosten said in the podcast that a study from Hong Kong found that half of the virus particles that an infected person emits through breathing and coughing are emitted in the form of aerosols. The other half is ejected in the form of larger drops. The larger drops quickly fall to the ground, but the aerosols can float in the air for a relatively long time.

Based on this, NUjij readers have probably concluded that 50 percent of the infections were shown to be from aerosols. However, Drosten did not say this and has not been studied in the research to which he referred.

How do respiratory viruses spread?

  • Coronavirus is the name for a type of virus. There are multiple coronaviruses. Corona viruses include SARS, MERS, various cold viruses and the virus that is now causing a pandemic.
  • There are multiple ways in which respiratory viruses, such as the flu and coronaviruses, can spread. You can become infected with a respiratory virus through direct contact, for example by kissing an infected person, you can become infected through indirect contact, for example because there are virus particles on the door handle and you can become infected through the air.
  • In the air, the transmission can take place again in two ways: via large cough, sneeze and speech drops that fall quickly to the ground and through aerosols, which float longer in the air and which can therefore infect someone at a greater distance. Whether each form of transmission is possible and how large the role of each manner in which the virus can be transmitted probably differs per virus.

What research did Drosten refer to?

Drosten writes to NU.nl that the research he talked about in the podcast on Monday was not about the emission of this corona virus, but about the emission of the flu virus and cold viruses, including various corona viruses.

Coronavirus is the name for a group of viruses. The coronavirus that is now causing a pandemic is officially called SARS-CoV-2. SARS, MERS and various cold viruses are also coronaviruses.

Drosten expects this coronavirus to behave no differently in terms of aerosol emissions than coronaviruses that cause a cold.

The Hong Kong study did not examine how contagious the virus particles emitted were. It has therefore not been proven that the cold virus particles emitted in aerosols were sufficiently intact to make a person sick.

Larger drops important in spreading coronavirus

Drosten expects that contamination via aerosols will play a greater role in the current pandemic than contamination via indirect contact. For this reason, Drosten also argues that it is probably more important to ventilate than to disinfect objects.

However, according to Drosten, drops that are larger than an aerosol, which you can come into contact with when standing close to an infected person, are still very important spreaders of the coronavirus. Keeping your distance helps to prevent contamination via these drops.

The RIVM writes that the spread with the coronavirus mainly takes place via larger droplets, which do not travel more than 1.5 meters through the air. Whether virus transmission via aerosols, especially during sports and singing, plays a role in the spread of the coronavirus is still being investigated, according to the RIVM.

See also: Roll aerosols unproven, we do know about coronavirus spread

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