Dear Tamar,

 

Something I just received from regional Office, but not much additional value.

Just in case you find anything useful in the message.

 

“Risks of COVID-19 spread through heating, ventilation, and air conditioning (HVAC) systems in non-healthcare settings

Currently available evidence supports that the predominant route of human-to-human transmission of the SARS-CoV-2 is through respiratory droplets and/or contact routes.

•                     Droplet transmission means that any person who is in in close contact (generally considered to be within 1 meter) with someone who has respiratory symptoms (e.g., sneezing, coughing) is at risk of having his/her mucosae (mouth and nose) or conjunctiva exposed to potentially infective respiratory droplets (which are > 5-10 μm in diameter). Moreover, droplet transmission may involve fomites in the immediate environment around the infected person. Therefore, contact transmission can happen for SARS-CoV-2 by direct contact with infected people and indirect contact with surfaces in the immediate environment or with objects used on the infected person.

•                     During some aerosol-generating procedures (tracheal intubation, non-invasive ventilation, tracheotomy, cardiopulmonary resuscitation, manual ventilation before intubation, and bronchoscopy) have been associated with an increased risk of transmission of coronaviruses.

 

Some scientific articles are suggesting that HVAC system may play a role on airborne transmission of COVID-19. However, to date no convincing epidemiologic evidence is available to support that the COVID-19 virus can spread through HVAC systems.

 

Basic principles of physical distancing (at least 1 m), surface cleaning and disinfection, hand hygiene and other strategies of good hygiene in combination with containment strategies (detect, isolate, treat and contact tracing) are the key measures to prevent COVID-19.

 

International societies are suggesting some actions related to HVAC systems

-              Increase ventilation rates and increase the percentage of outdoor air in the system

-              Extend the operation time of the ventilation system

-              Check that the ventilation units are properly set up and they are serviced correctly in accordance with the manufacturer’s instructions

 

In the context of the national university entry exams, we recommend national authorities to refer to the WHO considerations for school-related public health measures in the context of COVID-19 (available at https://www.who.int/publications-detail/considerations-for-school-related-public-health-measures-in-the-context-of-covid-19). “

 

With best regards,

Silviu

 

 

 

 

Thanks a lot!

 

 

FYI – the most recent one…

 

Best regards,

Silviu