Effectiveness of non-pharmaceutical interventions to contain COVID-19: a case study of the 2020 spring pandemic wave in New York City

Abstract

As COVID-19 continues to pose significant public health threats, quantifying the effectiveness of different public health interventions is crucial to inform intervention strategies. Using detailed epidemiological and mobility data available for New York City and comprehensive modelling accounting for under-detection, we reconstruct the COVID-19 transmission dynamics therein during the 2020 spring pandemic wave and estimate the effectiveness of two major non-pharmaceutical interventions—lockdown-like measures that reduce contact rates and universal masking. Lockdown-like measures were associated with greater than 50% transmission reduction for all age groups. Universal masking was associated with an approximately 7% transmission reduction overall and up to 20% reduction for 65+ year olds during the first month of implementation. This result suggests that face covering can substantially reduce transmission when lockdown-like measures are lifted but by itself may be insufficient to control SARS-CoV-2 transmission. Overall, findings support the need to implement multiple interventions simultaneously to effectively mitigate COVID-19 spread before the majority of population can be protected through mass-vaccination.

Epidemiological characteristics of three SARS-CoV-2 variants of concern and implications for future COVID-19 pandemic outcomes

“…In addition, the B.1.351 variant would be slightly more competitive if the vaccines are less effective against it than the P.1. variant (Fig 4B and Table S1), as has been shown in laboratory studies 7,9 . Tallies of model-projected infections (Fig 4B) and deaths (Fig S4) reveal four key determinants of future pandemic outcomes.…”

“…Our estimates of the level of immune evasion for the B.1.351 and P.1 variants are also consistent with antibody neutralization data suggesting both variants can evade prior immunity induced by infection and vaccination, though to a larger extent for the B.1.351 variant. 7,9 Here we provide joint quantification of immune escape and the change in transmissibility for both variants. Overall, the model-inference system estimates and model simulations suggest that both B.1.351 and P.1 are likely more competitive than the B.1.1.7 variant due to their greater propensity for immune escape.…”

“…wild-type and B.1.1.7) via cross-protective immunity; 2) variant-specific transmissibility and population susceptibility, based on estimates derived in this study; 3) variant-specific vaccine efficacy under different scenarios (see Table S5); 4) age-specific differences in vaccination coverage at the start of simulation and vaccination uptake rates for the simulation period (see Table S4); 5) seasonality; and 6) changes in NPIs under different scenarios (see Table S5). We used data from NYC for baseline vaccination coverage 32 and initial prevalence of different variants, 33 as well as key model estimates (e.g., transmission rates and infection fatality risk by age group; see Table S5) 17, 34, 35 . As in previous work, 17, 34, 35 we included 8 age-groups (i.e.…”

COVID-19 case doubling time associated with non-pharmaceutical interventions and vaccination: A global experience

“…The finding regarding the high effectiveness of vaccine rollout accords with clinical evidence that COVID-19 vaccines have high efficacy in reducing the incidence of SARS-CoV-2 infection [ 29 , 30 ]. Prior to the introduction of vaccine rollouts, scholars discovered that lockdown-like NPIs had a larger effect on reducing transmission than public health NPIs, including face covering, did [ 6 , 11 , 13 ]. By including post-vaccination periods, we determined that the marginal effect of vaccine rollouts appears to outweigh those of NPIs.…”

“…Brauner et al estimated the effectiveness of NPIs for 34 European and 7 non-European countries between January and May 2020 [ 8 ], and Haug et al assessed the effectiveness of worldwide NPIs implemented in March-April 2020 [ 9 ]. Other studies have examined the effects of NPIs during spring 2020 [ 10 - 13 ]. More recently, scholars have reported the combined effects of NPIs and vaccine rollouts based on simulations of epidemiological models for the United Kingdom [ 14 ], the United States [ 15 ], Italy [ 16 ], and China [ 17 ].…”