Various public health measures have been adopted to combat the spread of SARS-CoV-2, but there is no silver bullet which can single-handedly put an end to the pandemic. This requires a multi-faceted approach leveraging all the tools we now know to be effective in COVID-19 detection and helping to limit its transmission.
COVID-19 is an enduring risk to public health. Every facet of society, from academia through to healthcare, has struggled to cope with seismic shifts in their risk mitigation strategies. Namely, how can they possibly continue to operate in a period of widespread employee absences, and in such unstable public health conditions? Fortunately, we now have a greater understanding of the pain points in risk mitigation strategies and how best to support them. Most facilities opt for a combination of individual testing for COVID-19 detection, social distancing, and surface cleaning; protocols which exist against the backdrop of greater vaccine uptake. Therein lies an example of the multi-layered approach that can be taken to safeguard public health.
The layers of COVID-19 mitigation strategy
- Vaccines are a critical protective measure shown to significantly reduce COVID-19-related disease, hospitalization, and death. Currently, average daily cases among the unvaccinated population of the U.S. are six times higher than those among the fully vaccinated population1. However, they cannot provide complete protection, and vaccine effectiveness must be continually monitored to observe ongoing effectiveness, particularly against emerging variants, like the now dominant omicron strain.
- Masks are one of the most enduring symbols of the pandemic, and though the science has proven their effectiveness in reducing the risk of transmission, debate about their utility continues. Nevertheless, as with vaccines, breakout cases can occur even with diligent mask-wearing.
- Testing is our chief method of COVID-19 detection at the diagnostic level. It allows us to carry out contact tracing, and to diagnose cases in symptomatic and asymptomatic individuals alike. But testing alone isn’t sufficient for containing the virus.
- Social distancing is the main behavioral method we can deploy as a community to help limit the spread of COVID-19. However, its effectiveness indoors leaves much to be desired, as in-air pathogens may remain suspended in air for many minutes after an infectious person has left.
- Ventilation has been touted as an important facet of any COVID-19 mitigation strategy since the early days of the pandemic. It was clear relatively early on that the main route of transmission was through inhalation of respiratory particles. So, facilities aimed to combat in-air pathogens through ventilation. In some regions CO2 monitoring is used as a measure of ventilation efficiency.
- Disinfection was a hot-button issue at the start of the pandemic, but we now know that indirect contact through fomite transmission is a much smaller risk than via airborne pathogens. Still, facilities are urged to regularly clean surfaces, and to disinfect indoor spaces if/when there is a confirmed case in that community setting.
- Environmental surveillance paired with PCR testing is another layer/tool in that it presents us with an opportunity for community-wide COVID-19 detection, using a choice of surveillance methods. For instance: Air sampling paired with PCR testing is becoming increasingly prevalent, especially as a complementary solution to asymptomatic testing for full site coverage at the individual level as well as the environmental level.
Each of these individual layers provides varying levels of protection. We cannot rely on half-measures when battling an ongoing pandemic. The solution is to combine these protocols into a robust, multi-layered approach to COVID-19 mitigation. Many facilities are already implementing several of these layers with decent efficacy, but one aspect which is consistently lacking is environmental surveillance. This last step is absolutely crucial as it can help monitor each preceding step in the chain.
With effective airborne pathogen identification, you can help to determine whether your current risk mitigation strategies are sufficient or not. There has been an element of inconsistency with screening since it was first rolled out. Namely, if your COVID-19 detection protocol is based on on-site testing once or twice a week, what happens if COVID-19 is present onsite on a non-testing day? Environmental surveillance gives you the insight needed to help confirm that strategies are working, as well as the data necessary to change protocols proactively when they are not.