Hyderabad: Prime Minister Narendra Modi during a video conference with chief ministers on 3 April, had called for a common exit strategy to ensure staggered re-emergence of the population once the Covid-19 lockdown ends.
But before initiating an exit strategy, we need to assess our current preparation and decide where we need to focus our continuing response efforts.
Media reports have highlighted the chronic shortage of beds, infrastructure, equipment, personnel in general and how this will be even more exacerbated during a potential surge in demand.
India is estimated to have about 48,000 functional ventilators mostly concentrated in urban areas, whereas the country would need several fold more in case there is an uncontrolled spread. This has pushed the government to reach out to academia, innovators and even the corporate sector, such as inviting auto makers to initiate and ramp up production of ventilators, while banning all export of this critical medical device.
In all of this, however, there has been an abject neglect of the art and science of contact tracing.
Contact tracing includes locating and monitoring those who have come in contact with positive patients. It involves locating all contacts of a positive patient, listing them and then regularly following up on them for signs of symptoms and testing for infection.
It is accepted without much debate, almost as a public health dogma that contact tracing only plays a key role when the cases and chains of transmission are manageable.
But it can be important to prevent transmission in both containment (breaking all chains of transmission) and mitigation (slow the spread of the virus by social distancing/ flatten the curve) phases of the pandemic response.
Around 266 of the 410 districts surveyed by the government were found to be grossly underprepared for Covid-19 with insufficient number of ventilators, testing kits, and PPEs. Given this, contact tracing to prevent as many cases as possible and subsequently reducing health care exposure becomes an important central option.
Overemphasis on ventilators?
It should be remembered that a majority of Covid-19 patients recover with mild illness (80 per cent), another 15 per cent have relatively severe illness. Only five per cent need ICU care, of which a smaller proportion would need ventilators.
Ventilator availability does not ensure functionality, which in turn does not guarantee survivability. In fact, survival rates of Covid-19 patients who require ventilator care is fairly low, varying from 14 per cent to 34 per cent.
Ventilators also require highly-trained teams of doctors, nurses and paramedics to ensure provision of high-quality critical care through proper use, care, and maintenance.
For instance, the British Covid-19 patient who was discharged from Ernakulam in Kerala was treated by a multidisciplinary team of eight doctors, his sample collection and maintenance was done by four doctors, nursing care by five nurses including infection control and they were assisted by two dieticians, along with other support staff.
At a bare minimum, factoring in shifts, one ventilator unit needs at least four nurses and five units need four resident doctors for round-the-clock care. Even if new personnel can be trained, they will all need to be provided with appropriate PPE because intubation and ventilator-based care is a high-risk procedure given the possibility of aerosol generation.
Ventilators also require 24×7 availability of electricity, oxygen, and other maintenance parts.
Not emphasising on rigorous contact tracing is as problematic as the lack of ventilators. Climbing cases, especially of asymptomatic ones, each with multiple contacts can make contact tracing seem pointless. But contact tracing need not stop even when the cases are climbing. Containment and mitigation are not necessarily mutually exclusive but rather a continuum.
It’s important to remember that a contact successfully traced, isolated early and treated if sick, could prevent between two to three further new infections.
Sustainable contact tracing systems
Several states such as Odisha and Telangana have started recruitment drives for specialist healthcare workers to meet the surge in demand and NITI Aayog’s call for volunteer doctors has already received over 31,000 applications.
But there isn’t a similar initiative to recruit, train and deploy a large pool of contact tracers. In fact, current contact tracing duties are probably taking away healthcare workers from other key functions in health systems, perhaps to the detriment of functions like immunisation, and other health programmes.
Having a pool of trained contact tracers who are part of a strengthened Integrated Disease Surveillance System team supported by good quality accessible testing will play a critical role for the medium to long term, to prevent sporadic outbreaks or a potential second Covid-19 wave. The current policy does not seem to put in place a long-term strategy that can withstand any eventuality post lockdown.
Large-scale contact tracing may appear daunting and impractical to a diverse country like India. How can India replicate Singapore or South Korea which are smaller and homogenous countries, especially given asymptomatic transmitters?
The foremost requirement is political will.
In Wuhan, at the peak of local spread, China had 1,800 teams of five people each to trace 6,85,000 contacts. We need to recruit a sufficient pool of people, train them, and deploy them. This resource will be useful for us in future routine health activities such as communicable and non-communicable disease surveillance, as well as to help us be better prepared for other infectious epidemic onslaughts in the coming years.
A much simpler task
Training contact tracers is much simpler, quicker and practical compared to training healthcare professionals on intensive care.
For surveillance, technology can be incorporated with appropriate ethical safeguards. This can include smartphone apps to track nearby contacts in public spaces or to observe contacts’ adherence to quarantine. CCTV camera footage can aid police and transport departments for comprehensiveness.
We may not be able to detect all asymptomatics but they can only spread infection for 14 days and we can break that transmission chain at the next stage — through contacts that develop symptoms from such cases.
A Covid-19 case on an average infects 2.79 persons, a number called basic reproduction rate, R0. But this isn’t set in stone, our actions like hygienic measures and correct use of homemade masks will reduce this.
A study showed that for controlling outbreaks with an R0 of 2.5, more than 70 per cent of contacts had to be traced. But for a 1.5 R0, a majority of outbreaks were controllable with less than 50 per cent of contacts successfully traced.
There is a scientific surgical approach to breaking the transmission chains. The government’s containment plan and micro plan documents currently paint a sledgehammer approach to containment. Cluster containment is simply a miniature lockdown of a “hot zone of 3 to 5 km radius” from cases’ with a buffer zone, regardless of the cases’ travel pattern or social networks.
Using existing front-line health workers, the government imposes travel restrictions and other curtailments that may not only endanger community participation but also stigmatise the involved communities if not implemented with care. Managing a district or a large city with three to six discrete hot zones can lead to confusion and uncertainty and is untenable as a strategy in the long term.
Ventilators dominate the public discourse, perhaps driven by what Atul Gawande calls the heroic expectation of how medicine works — the image of doctors saving a person from the clutches of certain death is fascinating.
A contact tracer with a clipboard requesting a list of people with whom the patient spent more than 30 mins within two metres proximity in the last seven days appears mundane by contrast. But in discounting the lucid and effective strategy of contact tracing, we forget that in responding to extraordinary pandemic situations, simplicity might be the ultimate sophistication.
Dr Manjunath Shankar is a public health specialist. He participated in the US CDC Emergency Response (Modelling Task Force) to the West African Ebola outbreak in 2014-15.
Dr Anant Bhan is a researcher in global health, bioethics and health policy.