Covid-19: Viral Load & Distancing

In the world's broad field of battle,

In the bivouac of life,

Be not like dumb, driven cattle!

Be a hero in the strife!

Trust no future, howe'er pleasant!

Let the dead past bury, its dead!

Act, --act in the living present!

Heart within, and God o'erhead!

                H W Longfellow

                A Psalm Of Life

Covid-19 has swayed a death and remorse spell throughout, impacting the economy, livelihood and many other ecological aspects of our humanity. When, as of today, we were supposed to be doing things at offices, institutions and(or) various other sectors, we simply sit at home, distancing ourselves from the important work and a better future.

On an eagle-eyed view, things all around reflect only dismay and pain. Sitting in a room, brains going mundane, feelings of floating endless in a dead sea and praying to socialise again, are some random cyclic thoughts that beseech you into boredom. It looks as if the whole civil society is fighting a war against an enemy that feeds and gains strength on the weak links of the society- the physical relationships.

Although the war looks unending, and requires a great sacrifice on many scales, there is only one method through which this could be fought- to limit the physical contact from an infected pool to healthy pool. Reckon the plagues, the great Spanish flu, Ebola and other such pandemic and you will see that the hard- hit sections of the world followed social distancing. Albeit, it’s the only option with us, but the world today is more mobile, tightly knit than earlier times and economically more connected, and thus the very solution, we are trying to follow, is sending us into deep trenches of abomination and trouble.

Gladly, the solution of social distancing could be improvised because the way these pandemics evolve follow a kind of similar blueprint of their ancestor’s evolution, but the world today has changed a lot. The domains of biotechnology, artificial intelligence and higher strategic managements could be applied to fight such wars and break the neck of this invisible enemy.

In a country like India, where we have nearly 50000 ventilators and a population of 150 crore, that too varying in diversity and opinions, a blanket lockdown just brings revolt and hairline fractures in the plan that could impact the country in the coming future. Indian system, albeit working hard, should change to a different mode of social distancing after a definite period of lockdown (say from 22 march to 15 may). This mode of distancing should not be a blanket lockdown but a strategic clustering lockdown on the basis of scientific targeted testing and demographic economic advantages.

The Viral Load:

To substantiate on the strategies and the policies that government should bring in, let me take you to an interesting concept - the dynamics of the SARS-COV-2 virus inside the host body (the concept is taken from here by Dr. Siddhartha Mukherjee). Dr. Sid Mukherjee explains the importance of quantification of virus in the human host. Each human has a dynamic equilibrium point, known as Peak Viremia, after which the virus replication settles. If this Peak Viremia is high, then people become prone to the disease sooner. In simple terms, the more the virus can replicate itself in the host, the more prone the human body becomes to catch the covid-19 severely. And since, this "virus load" fights off diligently with the immune system of the body, the fluid excretions of the body are also full of the virus contamination. In early times of Covid, due to paucity of data a robust correlation between this virus load factor and severity of disease was not made, but recent research ( peer reviewed) show a promising result in the high virus load factor and severity of disease. ( More information could be found here)

Graphical representation of behaviour of Virus in P1 and P2.

P1 is more close to getting severe covid-19 compared to P2, as P1 has higher Viremia.

So, given the above information what could be done with it? How can it be used? Can quantification of viruses in the host help with better social distancing policies? Currently, the governments across are mainly focussing on the spread of diseases and trying to reduce the spread by blanket quarantining policies, but what if they somehow understood the behaviour of flow of viruses from one host to another? The quantification of number could help us here. To understand how this concept fits in the policy making area let's move to understand the economic perspective of the Indian demography.

Economics of Indian Demography:

India, majorly, is divided into three types of demography - urban, sub-urban and rural. The urban cities are high economic zones with all corporate related stuff happening. These places in India are comparatively much capable of adhering to quarantine rules and getting best medical care. However, the sub-urban and rural areas are the ones that would take a huge blow, if the pandemic is not curtailed in time. The threat is quite evident from the exponential growth of cases in UP, Mumbai and worrisome local transmissions at Dharavi. Although we see the UP, Bihar and slum regions such as Dharavi, as sub-urban, rural and underprivileged parts, 60-70% of the economy of India runs on these regions. Why? Because they are the major contributors to the Indian Unincorporated sector. More on this could be found in a book by Prof. R Vaidyanathan ( India Uninc). Once the virus runs exponential through these golden economic mines of our country, India might be heading towards a crisis greater than all plagues, wars and the great depression. Imagine, a lockdown extended to August or September. It shall disrupt the whole Indian economy and bring the country to its knees. A close look at the Input-Output matrix shows the interdependence ( please find an empirical table for the Indian economy in 2007-08 attached)

Source: Indian Ministry of Statistics ( I/O) Data

If one sees in the table, one can see how high contributions of the primary, secondary and tertiary sectors in India are. Albeit, contributions of primary sector in India are declining at a very high rate, still the India Uninc, contributes majority of contribution to Indian exports and internal usage. The Covid spread in Uninc. rich demography could rupture the economy at an unimaginable rate, possibly also with very high number of deaths.

So, to control the tailspin and a prospective broken economy and curtail the pandemic, with a very less burden on the healthcare systems, Government needs to re-design the aspects of social distancing for these places. How can that be done? And how does a viral load factor help here? For that let's first understand the covid matrix.

Covid Matrix:

McKinsey today came out with a document suggesting plans for different countries to curtail the pandemic at least cost of economic loss by dividing the situation of the pandemic into a set of matrix. A pictorial representation of the spread could be found below:

From McKinsey Insights: How to restart national economies during the coronavirus crisis

From the above 8X8 matrix, the government could easily plan steps to move from a highly deadly zone (A) to a relatively safe zone (B). But the idea on paper assumes a strict lockdown meaning no movement, better testing capabilities and no political jargon. Alas! India loses on all three fronts here, as India lacks the political apparatus that a strict regime possesses, the healthcare system in India is well below the danger watermark level, and we all know the type of political system that governs India. Still, with a robust plan to follow the path of the matrix above, combined with a nice testing strategy that optimises the equipment present to target the early spreaders and quarantining the clusters shall help India ace the fight against covid-19. Here is where the testing strategies to take the viral load into picture, and target testing comes in handy. They actually could help in targetted quarantining and low load on the intensive cases of the healthcare systems, thus promoting the flattening of the curve at a higher speed. But how can that be feasible? How measuring the virus presence in the swab of a patient can help smoothen the curve at macro level? Based on my understanding of the spread of this contagion, I will try to present some ideas.

The Policy:

To make things clear, I have divided the policy into a top-down approach, that starts with finding the hot pandemic affected areas and hunting down to clusters using the concept of advanced virology and viral load factor in the local transmissions.

i) Identifying the high pandemic areas:

The first step is to check the highly affected areas in each state and enforce more healthcare workers, police machinery in those areas. To hunt that down, government already has ample data per state and locality basis to do the same. Apart from that, to hunt that down, Government must investigate the progression of spread in those areas. Government can use easily the McKinsey template ( described above) to locate such areas, and prioritise the sub-urban and rural areas ( as these are high economic yields for our country). Once these areas are identified, the second step comes is to plan the containment.

ii) Containing and restricting the spread:

To understand the restricting of spread, let's understand mathematically how the virus spreads.

# new cases = e^(R0*n)

where n is the number of days for virus's incubation, R0 is the number of persons who get infected by one person.

So, to know the spread if one takes logarithm on both sides of equation, we get

R0 * n = ln(new cases)

So, the logarithmic equation gives us the spread of the new cases in n number of days. And in India, this value is ever increasing:

Source: https://www.covid19india.org/

So, to curtail this spread, one can't reduce the number (n) as it is a fixed incubation timing for the virus, but one could definitely reduce the R0 ( the initial spread). Now how the value of R0 could be curtailed? Here comes the concept of viral load factor. Consider, everyone affected with virus has its own R0. Recall from the first graph about viral load factor, since P1 has a high viremia and P2 has a low viremia, the spread of viruses from both these people differ. So (R0)p1 >> (R0)p2, given the fluids of P1 are led with the virus. If Government during the swab collections differentiate the patients on basis of their viral load factor and the way viruses reach the peak viremia level, based on the antibody tests and other biological apparatus, I believe the R0 collectively could be brought down. 

How that could be done? Government could conduct the testing of people based on contact and label people on basis of the viral load factor tendency present in them.

Suppose in the above case, P1 is labelled red ( prospective extreme super spreader) and P2 is labelled blue ( normal spreader), P1 and immediate contacts in a particular cluster could be easily curtailed into quarantine and early remedies of the first aid medicines ( such as antibiotics, HCQs that helps to inhibit the replication of RNA in cells by lowering Ph) can be given to them. Once the super spreaders are found early, quarantined, their immediate contacts quarantined and given early stage antibiotics to supplement the immune system, the government could easily be trying to reduce the R0 ( initial spread by great amount) and thus in a period of 14 days, we will see a drastic slowdown in the cases. And if the R0 value decreases, the healthcare systems can be efficient to treat the pipelined critical cases, the public machinery would not be overwhelmed, and the cluster distancing could be easily maintained.

Imagine how getting one person with high load factor can create a difference to the economy's output and help India Inc. get back to its running toes in a shorter span of time. 

Although, writing about a policy is easy and its implementation is tough, I believe, with the limit of knowledge I possess, a strategy on similar lines can help India to curb the lockdown to shorter period and assist our healthcare workers in a very optimal way.

As I started this article with the legendry texts by H W Longfellow, it is a time not to be dumb and execute weak policies. This is a time to learn from past, analyse the behaviour of spread and act towards a better future. Hitherto, Indian Government has done a marvellous job to curtail the pandemic, but the diversity and the above-mentioned economic factors of the country must be taken into account once the lockdown crosses 40 days. As Longfellow writes, the past is gone, and future might not be as pleasing, with hope, logic and belief, we can curb the pandemic as a nation. With good policies, we can win the war. If we take all measures properly and logically, sometime in future over a cup of coffee, we would be hymning the lines by Longfellow - In the bivouac of life, we were not like dumb, driven cattle! We were hero in the strife!