Written by Bhagyashree Dutta and Dr Chandrima Chatterjee 

In December 2019, in Wuhan, China, a cluster of unusual severe pneumonia cases with unknown causes were reported. These were later identified as caused by a novel strain of coronavirus [1]. Severe acute respiratory syndrome, coronavirus 2 (SARS_CoV-2) outbreaks, was declared a global pandemic by the World Health Organization on March 11th, 2020 [1].  Around 216 countries had been affected by this ongoing pandemic, and the number of confirmed cases and death is still increasing [2]. This disaster had been a matter of great concern as it had negatively impacted millions’ health and countries’ socioeconomic status. To fight this battle without any pharmacological weapons like medicines and vaccines, the countries had adopted various public health measures known as non-pharmacological interventions (NPIs).

Non-pharmacological interventions are strict actions against novel coronavirus disease (COVID-19), implemented to interrupt or reduce transmission [3]. It includes various measures like environmental measures, social and physical distancing measures, travel-related measures, and personal protective measures [3]. All these measures are intended to reduce the size of epidemic peaks and buy time to prepare the health system to manage colossal patient load and develop effective vaccines and drugs [4]. There are two strategies under NPIs, namely suppression and mitigation [5]. Suppression aims to decrease the number of cases up to a level where the reproduction number R reaches 1 and human to human transmission is eliminated. These NPIs should be maintained until an effective vaccine is available [5]. Whereas mitigation intends to slow the transmission by reducing R (not less than 1) and helping lessen the health impact due to COVID-19 [5].

Non-pharmacological intervention consists of a lot of measures taken in combination to varying degrees according to their feasibility. Personal protective measures include hand hygiene, respiratory protocol, facemask, while environmental standards include regular surface and object cleaning, use of ultraviolet lights, increased ventilation, etc. [3]. Social distancing measures include contact tracing, isolation of sick individuals, quarantine of exposed individuals, school and measures and closures, avoiding crowding [3]. Travel-related measures include travel advisories, entry and exit screening, international travel restriction, and border closures [3].

The effectiveness of these measures had been documented in various countries. A study to compare the effect of various NPIs in China found that there would be a 67-fold increase in COVID 19 cases if the NPIs were not implemented [4]. There had been an enhanced need to use integrated NPIs for better results. Another study to estimate the impact of non-pharmacological intervention on 11 European countries found that lockdown reduces transmission significantly.  It is important to acknowledge the importance of these interventions and spread awareness among the people of the community to follow the same apart from getting vaccinated. The intervention should be continued to keep the COVID-19 under control [6].

Effectiveness of NPIs:

Personal protective measures- wearing proper face masks and following good hand hygiene by using soap and water or alcohol-based hand rub is one of the most basic and practical steps that can be done at an individual level to prevent the spread of infection [7]. (Provided there is access to it).

Environmental measures – coronavirus can be inactivated in a minute by using a high concentration of ethanol (more than 70%) or bleach solution (0.01%), and this is important because  SARS-CoV2 has the ability to stay active on surfaces(plastic, metal, or glass) up to 9 days [8].

Physical distancing measures- Contact tracing is an essential public health measure in the absence of proper treatment available for an outbreak. It helps identify individuals who may carry the infection without showing symptoms, ultimately preventing further transmission [9]. Isolating infected individuals- in Korea, it has been found that a quick and proper mechanism to isolate sick individuals along with high rates of community testing has helped to control the spread of infection [10].

Quarantine- quarantine of people exposed to infected cases reduces 44 to 81% of new infections and 31-63% of death compared to taking no steps [11]. School measures and closures- in the United States of America, schools’ closures and limits on public gatherings have been shown to reduce the transmission of infection to a large extent due to limited community movement [12].

Travel related measures – Entry and exit screening – screening doesn’t identify infected (50-70%). The asymptomatic, or the pre-symptomatic individuals or individuals who are unaware of their exposure, can be identified. So it becomes crucial to consider this while making policy to fight COVID-19 [13].Internal travel restriction- internal travel restriction can delay the spread of the epidemic but not necessarily stop the progression to a large extent. A modeled study estimates that Wuhan’s internal travel restriction can buy time for 3 -5 days for mainland China to prepare for the disaster [14].

Border closure- in a modeling study done in Japan, it is estimated that border closure could reduce 70% of the COVID-19 cases outside China; however, this can only delay the epidemic by just two days [15].

Impact of Non- pharmacological Intervention:

Non-pharmacological interventions are seen to be very useful in a global threat like this. Nevertheless, countries have to bear a significant socioeconomic loss because of this [3]. Prolonged lockdown and closures of business result in an economic crisis, while the closure of school also threatens the future of children and society as a whole. Moreover, the mental health of people is also affected due to such stringent policies. In a cross-sectional study done across all regions of Norway, it was found that there has been a two to threefold increase in anxiety and depression symptoms associated with public health measures like lockdown, quarantine, isolation, and social distancing [16]. Therefore, it becomes necessary to measure each intervention’s socioeconomic cost and make each intervention’s evidence-informed decisions [3].

Non- pharmacological interventions are robust solutions to fight this ongoing pandemic. In addition to vaccination, countries should continue to adopt such interventions by evaluating the effectiveness and socioeconomic cost to fasten their recovery.

Bhagyashree Dutta is a physiotherapist currently a postgraduate student, pursuing Master of Public Health (Health Policy) at Prasanna School of Public Health, Manipal Academy of Higher Education (MAHE), Manipal, India.

Dr. Chandrima Chatterjee is a dental surgeon and currently a postgraduate student, pursuing Master of Public Health (Global Health) at Prasanna School of Public Health, Manipal Academy of Higher Education (MAHE), Manipal, India.


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