Strict COVID anti-contagion policies can provide long-term health benefits

By Sreetama Dutt M.Sc.Dec 5 2021Reviewed by Benedette Cuffari, M.Sc.

Vaccines may be the first line of defense against the severe acute respiratory syndrome coronavirus (SARS-CoV-2). The coronavirus disease (COVID-19) pandemic was declared as one in March 2020; however, containment measures were not widely enforced until several months after this declaration. Eventually, most governments around the world declared lockdowns across states and countries and enforced strict anti-contagion policies like masking and physical distancing to curb infection rates.

Study: Short- and medium-term impacts of strict anti-contagion policies on non-COVID-19 mortality in China. Image Credit: Chansom Pantip / Shutterstock.com

Background

The key to evaluating the welfare implications of anti-contagion policies is to examine their short- and long-term public health consequences. Multiple studies have shown that strict physical distancing and human mobility restrictions can effectively control the spread of SARS-CoV-2 and ultimately prevent deaths. However, the efficacy of such interventions and their effects on disease patterns and deaths from other causes remains debatable.

According to one theory, measures like lockdowns could harm overall population health in the shorter term, as human mobility restrictions would reduce access to healthcare services. Additionally, business restrictions might lead to sharp economic disruption and massive layoffs, thereby affecting economies significantly.

In contrast, theories in support of these policies argue that, without effective interventions, the pandemic would cause greater health damage over time, as adverse economic damage could be more substantial and a larger number of COVID-19 patients might jeopardize healthcare provision.

However, there is also speculation virus containment policies might bring about unintended health benefits because they encourage protective health behaviors like masking and physical distancing. These measures could subsequently reduce risks associated with business activities like improving air quality, reducing work and traffic accidents, and reducing the transmission of other infectious diseases like seasonal influenza.

In a recent Nature Human Behavior study, researchers assess the short- and long-term benefits of these policies on health outcomes in the Chinese population.

About the study

In the current study, the researchers used comprehensive and representative death records from China’s Disease Surveillance Points (DSP) system, covering more than 324 million people in 605 DSP districts/counties in 321 cities. These records accounted for 24.3% of China’s population. Additionally, the researchers collected information from various news media and government announcements on whether a city implemented non-pharmacological interventions like lockdowns.

Matching the datasets, the researchers constructed a daily DSP site-level panel dataset from January 1, 2020, to July 31, 2020, which included 1,105,938 death records in the DSP system that were reported until September 28, 2020.

Researchers used a three-point analysis system to assess the impact of strict anti-contagion policies. Firstly, they estimated the short-term impacts of these policies on the number of deaths from various causes, including cardiovascular diseases (CVDs), injury, acute lower respiratory infections (ALRIs), chronic lower respiratory infections (CLRIs), neoplasms, and other causes during the study period.

Secondly, the researchers investigated whether these policies had long-lasting impacts on public health. In the third step, they analyzed the heterogeneous impacts of these policies across different cities. They hypothesized that results might differ along several dimensions including income levels, industrial structure, initial health status, and initial pollution level.

Study findings

Using death registries based on 300 million Chinese people and a difference-in-differences design, the researchers calculated that China’s strict anti-contagion policies during the COVID-19 pandemic significantly reduced non-COVID-19 mortality outside Wuhan by 4.6%. The health benefits persisted and became even more impactful after the measures were loosened. Ultimately, COVID-19 related mortality was reduced by 12.5% in the medium term.

There were significant changes in the behavioral pattern of the Chinese population who were now wearing masks regularly and practicing social distancing. There was a significant reduction in air pollution and traffic accidents that were assumed to have driven these results.

The researchers estimated that 54,000 lives could have been saved from non-COVID-19 causes during the 50 days of strict policies and 293,000 in the subsequent 115 days. These encouraging results suggested that virus countermeasures were not only effective in controlling COVID-19 in China but also brought about unintended and substantial public health benefits.

Implication

This study showed that strict anti-contagion policies were responsible for unintended short- and medium-term health benefits. There were fewer deaths from CVDs, traffic accidents, and ALRIs, and CLRIs during the period of SAPs.

These health benefits persisted into the post-lockdown period. Such interventions can therefore be considered sustainable alternatives to improve the health and quality of life of the population, even after the pandemic has subsided.