Considerations for implementing and adjusting public health and social measures in the context of COVID-19

Key Messages

• Public health and social measures (PHSM) have proven critical to limiting transmission of COVID-19 and reducing 

deaths.

• The decision to introduce, adapt or lift PHSM should be based primarily on a situational assessment of the intensity of 

transmission and the capacity of the health system to respond, but must also be considered in light of the effects these 

measures may have on the general welfare of society and individuals.

• Indicators and suggested thresholds are provided to gauge both the intensity of transmission and the capacity of the 

health system to respond; taken together, these provide a basis for guiding the adjustment of PHSM. Measures are 

indicative and need to be tailored to local contexts.

• PHSM must be continuously adjusted to the intensity of transmission and capacity of the health system in a country and 

at sub-national levels.

• When PHSM are adjusted, communities should be fully consulted and engaged before changes are made.

• In settings where robust PHSMs are otherwise in place to control the spread of SARS-CoV-2, allowing the relaxation 

of some measures for individuals with natural or vaccine-induced immunity may contribute to limiting the economic 

and social hardship of control measures. Applying such individualized public health measures must take into account a 

number of ethical and technical considerations.

Introduction

Public health and social measures (PHSMs) are being implemented across the globe to suppress SARS-CoV-2 transmission and

reduce mortality and morbidity from COVID-19.1 PHSMs include personal protective measures (e.g. physical distancing, 

avoiding crowded settings, hand hygiene, respiratory etiquette, mask-wearing); environmental measures (e.g. cleaning, 

disinfection, ventilation); surveillance and response measures (e.g. testing, genetic sequencing, contact tracing, isolation, and 

quarantine); physical distancing measures (e.g. regulating the number and flow of people attending gatherings, maintaining 

distance in public or workplaces, domestic movement restrictions); and international travel-related measures. In this context, it 

does not include medical countermeasures such as drug administration or vaccination. PHSMs act in concert, and a combination 

of measures is required to ensure adequate control. Measures should be implemented by the lowest administrative level for which 

situational assessment is possible and tailored to local settings and conditions.

Several important developments have occurred since the publication of the previous Considerations for implementing and 

adjusting public health and social measures in the context of COVID-19.

2 First, several COVID-19 vaccines have been approved 

by national regulatory authorities and through WHO Emergency Use Listing (EUL).

3 Vaccination has begun in most countries, 

bringing the prospect of significantly reducing severe disease and mortality further. Initial observational studies following rollout 

of vaccines suggest that vaccines may lead to protection against infection and a reduction in transmission,4–6 which in addition 

to PHSMs will help control the spread of the virus. Second, four WHO-classified variants of concern (VOCs) have emerged 

since December 2020,7,8 which are more transmissible and some of which may cause more severe disease9 and/or lead to a degree 

of vaccine escape, requiring potential adjustments to response measures to account for their different characteristics, including 

their impact on vaccine effectiveness. Several other variants of interest (VOIs) are also being monitored. Finally, more evidence 

is now available on the effectiveness of a range of individual and community-level measures (outlined in Table 3 below).

Control of SARS-CoV-2 will depend on: i) the prevalence of infection and of circulating variants; ii) the rate of growth or decline

in incidence; iii) the types, use of and adherence to control measures in place; iv) the speed with which vaccination occurs; v) 

the targeting and uptake of the vaccines among high-risk groups; and vi) vaccine effectiveness and natural immunity in the 

population.

10 National vaccination strategies should prioritize older individuals at highest risk of severe outcomes and health 

workers, to rapidly reduce mortality and the burden of disease and protect health care services. However, with successful 

COVID-19 vaccination of older populations following the prioritization of vulnerable groups, the virus may continue to spread 

among unvaccinated younger population groups.

11 After achieving high vaccination coverage of SAGE priority groups for stage