Nearly two years since it was first discovered, COVID-19 continues to rip through populations around the world. It has sparked a serious discussion on pandemic-preparedness and how governments around the world can update infrastructure to manage the existing pandemic, as well as address new diseases in the future.

Pandemic infrastructure has mainly been focused on supply chains for medical supplies, including personal protective equipment, therapeutic medicines and vaccines. But it also involves information, such as intergovernmental data sharing, systems of international coordination and contact tracing infrastructure.

However, one quite simple but hugely important area has not had the focus it deserves: buildings. More specifically, how buildings are ventilated.

On November 20 the Irish Times published an editorial, saying that the country’s COVID-19 surge is not reaching a crisis – but that it is already a crisis. Interestingly, the editorial criticized public health officials by saying that “almost two years into a pandemic caused by an airborne virus, ministers seldom even talk about ventilation.”

Ireland is an interesting case study on ventilation because half of the people who died from COVID-19 were infected in fewer than 400 buildings, even though there are over 2.5 million buildings in the country. This highlights that COVID-19 is indeed airborne and spread by inhaling infected air – not from contacting surfaces – and speaks to a problem with building ventilation.

However, this is not just a problem in Ireland but indeed all over the world.

For example, the United States’ Occupational Safety and Health Administration (OSHA) has a set Permissible Exposure Limit (PEL) for carbon dioxide of 5,000 parts per million (ppm) (0.5 percent carbon dioxide in air) averaged over an eight-hour work day. (For context, air quality with carbon dioxide of 1150ppm or less is considered ideal for indoor spaces).

Read more: How better indoor air quality can address COVID-19, future pandemics