Dr Jonathan Fluxman brings us a guest post investigating the research and narratives at play in perpetuating (and fighting back against) the myth that Covid-19 is droplet based and not airborne. He explores the consequences of this narrative and suggests some ways we can push back.
At the 2nd December 2022 weekly Independent SAGE briefing, Dr David Nabarro, WHO Special Envoy on Covid-19, said “…Covid is primarily, primarily, a droplet-borne infection, it may be airborne in certain circumstances, but we still in WHO contexts say its primarily droplet-borne…” 
This statement flies in the face of international scientific consensus that the pandemic is driven by airborne transmission of the SARS-CoV-2 virus. This was reiterated by a recent multinational Delphi consensus statement published in Nature in November: all 386 academic, health, non-governmental organization, government and other experts from 112 countries agreed that “SARS-CoV-2 is an airborne virus that presents the highest risk of transmission in indoor areas with poor ventilation.” 
Recognising the correct mode of transmission of Covid-19 is fundamental to our response to the pandemic. Widespread transmission continues to occur, in both unvaccinated and vaccinated populations, driving new mutations. In addition to deaths, hospitalisations and long covid, there is now evidence that repeated infections cause cumulative damage with each further infection  . It is clear that transmission must be addressed.
The ‘droplet precautions’ (hand washing, cleaning of surfaces, surgical masks) only make sense if that is Covid’s primary method of transmission, and since the available evidence points to airborne transmission, we need to also ensure there is clean indoor air and wear respiratory-grade facemasks (FFP2 or FFP3) to stop breathing in the virus. To date, official UK Infection Prevention and Control (IPC) guidance still rejects airborne transmission and says the virus is droplet-spread, except for so-called “aerosol generating procedures”. 
This rejection of airborne mitigation has had profoundly damaging consequences. Over 2,100 health and social care workers died from Covid-19 in the UK in the first two years of the pandemic , while almost 200,000 NHS workers have long Covid . Nearly 40,000 residents of care homes died from Covid-19 in the first year of the pandemic  while 11,600 patients died of Covid-19 they caught in hospital up until November 2021 . These figures are out of date, and will be higher now. Rates of hospital acquired Covid-19 infection have been high for most of the pandemic, reaching 36% in December 2022 . This compares with an OECD average of 6% for hospital acquired infections for other pathogens. 
While this is happening in our hospitals and care homes, within our schools the government instituted a nationwide program of CO2 monitoring and air filtering units, to reduce airborne transmission.  The Department of Health and Social Care itself launched a national public information campaign in November 2020, showing how Covid-19 spreads through the air, and encouraging people to ventilate their homes and indoor spaces . And the Chief Medical Officer said in a speech to a Confederation of British Industry conference in January 2022, “‘We have realised the extraordinary importance of improving the ventilation of workplaces – not just for Covid, but also for many other respiratory infections.”  It is simply not tenable to argue that airborne transmission happens in schools, our homes and workplaces, but stops at the front doors of the NHS and social care.
Dr Nabarro’s comment is consistent with the position of IPC within WHO,  and national IPC authorities, including here in the UK.  Since the start of the pandemic they have simply asserted that a droplet mode of transmission predominates, without providing any evidence. Dr Nabarro’s intervention is therefore a welcome opportunity to evaluate the evidence for this.
A detailed historical analysis of research on transmission of disease, by Jimenez et al, found no evidence for droplet transmission.  Here in the UK, Evonne T Curran, infection control specialist and Honorary Senior Research Fellow at Glasgow Caledonian University, carried out her own review; the result was the same: no evidence. All she found were circular references to unsubstantiated assertions that droplet transmission occurs, but no actual evidence. [18, 19]
A paper by Doctors in Unite  explores these and related issues in detail. For example why did UK IPC not follow WHO guidance which clearly says that in a pandemic due to a novel virus, precautions against all modes of spread Including “airborne precautions” should be taken?  This would keep health care workers and patients safe while the mode of spread is being fully elucidated. IPC instead ruled out any possibility of airborne spread, leaving staff and patients unprotected from airborne spread.
The pandemic is accelerating globally. The UK had five waves of Omicron in 2022, we are now in the first wave of 2023. We cannot afford any longer denial and obfuscation on the main route of transmission of the virus from WHO and IPC. It is time for Dr Nabarro, WHO and IPC to either produce the evidence for droplet spread, or to officially abandon this theory of transmission, and embrace airborne spread. We cannot wait any longer.
Suggested actions: If you visit your GP or a hospital or care home, wear a well-fitting FFP2/3 mask. Challenge any staff who tell you to remove it and wear only a surgical mask. Ask them about ventilation, use your CO2 monitor if you have one to check air quality. If you work in health/social care talk to your colleagues and your union, ask your managers about airborne protections. These are also good questions to be asking of non-medical places, no matter where you work or spend time.
Image is a screenshot of Dr. Nabarro on the indie SAGE zoom call.