Mathematical modelling suggests containment of COVID-19 possible
Mathematical modeling studies suggest containment of COVID-19 might be possible but success of containment operations “cannot be guaranteed” since there is efficient human to human transmission, the Union health ministry said on Saturday (May 16).
It also said there is no approved drug or vaccine for the treatment of COVID-19 as of now and Chemoprophylaxis with Hydroxychloroquine are recommended for healthcare workers and high risk contacts.
“Since there is efficient human to human transmission, success of containment operations cannot be guaranteed. Mathematical modeling studies suggest containment might be possible,” the health ministry said.
The government has drawn out a containment plan as clusters posing high risk of further spread of COVID-19 have emerged.
The cluster containment strategy aims to contain the spread of the disease within a defined geographic area by early detection of cases, breaking the chain of transmission and thus preventing its spread to new areas.
For institutional mechanisms and inter-sectoral coordination at the national level, the National Crisis Management Committee (NCMC) and the Committee of Secretaries (CoS) will be activated. The NCMC will coordinate with health and non-health sectors on issues flagged by the health ministry.
“The concerned state will activate the State Crisis Management Committee or the State Disaster Management Authority, as the case may be to manage the clusters of COVID-19,” a document by the health ministry read.
There will be regular co-ordination meetings between the Centre and the affected states through video conference, it said.
The document said India would follow a strategic approach for possible scenarios — travel-related cases reported in India, local transmission of COVID-19, large outbreaks amenable to containment, widespread community transmission of the disease, and COVID-19 becoming endemic in India.
According to the document, “Containment for large outbreaks through geographic quarantine strategy calls for near absolute interruption of movement of people to and from a relatively large defined area where there is single large outbreak or multiple foci of local transmission of COVID-19”.
“In simple terms, it is a barrier erected around the focus of infection. Geographic quarantine shall be applicable to such areas reporting large outbreak and/or multiple clusters of COVID-19 spread over multiple blocks of one or more districts that are contiguous,” it said.
The cluster containment strategy would include geographic quarantine, social distancing measures, enhanced active surveillance, testing all suspected cases, isolation of cases, quarantine of contacts and risk communication to create awareness among the public on preventive public health measures, the document stated.
As far as the evidence for implementing geographic quarantine is concerned, the document said that the “current geographic distribution of COVID-19 mimics the distribution of H1N1 pandemic influenza”.
“This suggests that while the spread of COVID-19 in our population could be high, its unlikely that it will be uniformly affecting all parts of the country,” the ministry said.
Large-scale measures to contain COVID-19 over large territories have been tried in China.
Mathematical modelling studies have suggested that containment might be possible especially when other public health interventions are combined with an effective social distancing strategy, the document stated.
The ministry listed some of the factors affecting large outbreak cluster containment. A number of variables determine the success of the containment operations through geographic quarantine which include the number and size of the cluster and also how efficiently the virus is transmitting in Indian population, taking into account environmental factors especially temperature and humidity, it said.
The factors also include public health response in terms of active case finding, testing of large number of cases, immediate isolation of suspect and confirmed cases and quarantine of contacts along with the geographical characteristics of the area.
According to the document, the authorities will do extensive contact tracing and active search for cases in the containment zone, test all suspect cases and high-risk contacts, isolate all suspect or confirmed cases, implement social distancing measures and intensive risk communication as part of the cluster containment strategy.
For large outbreaks amenable to containment, the document stated that the strategy will remain the same but vary in extent depending upon spread and the response to be mounted to contain it.