(CTN News) – During the Covid pandemic, social distancing and face masks “unequivocally” reduced infection spread, a report found.
Non-pharmaceutical interventions (NPIs) – not drugs or vaccines – were examined when used in packages that combine a number of complementary measures.
A Royal Society report called Covid-19: examining the Effectiveness of non-pharmaceutical interventions reviewed evidence gathered during the pandemic about six types of NPIs and how well they worked.
A few of them included masks and face coverings, social distancing and lockdowns, test, trace, and isolate travel restrictions, and environmental controls.
The review found that many of the NPIs used in the pandemic had positive – if limited – evidence of transmission reduction. Combinations of NPIs, however, showed a positive effect.
Further, NPIs were most effective at low transmission intensities, so they’re best used early in a pandemic.
Until drug treatments and vaccines are developed, NPIs are often the only controls for emerging infectious diseases.
As the pandemic showed, their use can have negative personal, educational, and economic effects, so assessment of their effectiveness is essential.
Prof Sir Mark Walport, the foreign secretary of the Royal Society and chairman of the report’s expert working group, said: “There’s enough evidence to say early implementation of complementary NPIs limited Sars-CoV-2 infections unequivocally.”
There’s no guarantee every NPI worked everywhere, but learning from this pandemic’s wealth of research will help us prepare for the next.
Social distancing and lockdowns were the most effective NPIs. Sars-CoV-2 transmission was significantly reduced by stay-at-home orders, physical distance, and reducing gathering size. According to the experts, the more stringent the measures, the bigger the effect.
There was a reduction in transmission and outbreaks in care homes with measures like cohorting and visitor restrictions.
Furthermore, the report found that school closures and other distancing measures reduced Covid-19 cases, but the effectiveness varied based on adherence and pupils’ ages.
Studies consistently found that face masks and mask mandates helped reduce infection rates. Moreover, higher-quality respirator masks (like N95 masks) are more effective than surgical masks.
Studies from countries that implemented contact tracing, with isolation of infected individuals and their contacts, found a reduction in Covid-19 deaths.
The report recommends setting up international protocols for clinical trials and observational research before further pandemics.
Prof Christopher Dye, professor of epidemiology at the University of Oxford, said: “The next thing is Disease X.”
‘We don’t know what it’s going to be, we don’t know where it’s going to come from. We need a system that can handle anything of that kind, and for me, the number one priority is to have a global surveillance response system.”
According to Christl Donnelly, head of department and professor of applied statistics at Oxford University, and professor of statistical epidemiology at Imperial College London, we can’t say for sure what might be implemented in the future.
The Coronavirus incident can be characterised, and that will inform decision-making, but if there is another pandemic, we’ll need more data.
In a special issue of Philosophical Transactions of the Royal Society A, six expert-led evidence reviews are gathered together.
Thousands of studies were reviewed, and papers that were sufficiently robust were selected for each review.