By Sandra Albert and Glenn Kharkongor
We are beginning to see state governments passing new rules and restrictions every day. Some of these rules vary from state to state, resulting in uneven regulations. To some extent, of course, the situation differs across the country. In any case, it should be the public health and scientific establishment that should advise the decision-making.
A unified national policy is also essential, as inter-state travel continues, though substantially decreased, and monitored at some state borders. After all, educational institutions and many workplaces are closed, and students and workers must return home, especially since hostels and guest houses have also been shut. Governments and citizens must heed public health advisories, otherwise it will soon be every man for himself and chaos will descend. Contradictory, piecemeal, and unnecessary regulations must be avoided by governments.
The Indian Council for Medical Research (ICMR) has taken the lead in public health announcements and Central Government policy has so far been aligned with ICMR pronouncements. The ICMR categorically states that there is no community transmission in India till now. International agencies such as the WHO have concurred with this assessment.
Country still at Stage 2
To recap, the stages of a pandemic are as below:
Stage 1: Imported and sporadic cases, who are only those who have travelled to virus-hit countries and test positive. They are quarantined and treated. Travel into India from abroad has been stopped from Mar 22-29, and the 1.4 million passengers who entered India shortly before this have been, screened, and placed in home quarantine.
Stage 2: Local transmission: This occurs when family members, friends, neighbours or other close contacts, contract the virus from an infected person from Stage 1. The source of the transmission is known, contacts can be located, and appropriate measures such as testing, treatment and isolation, are taken. India is at this stage now, and has tracked incoming travelers and their contacts. All 271 cases (total up to Mar 21, 2020 according to the Union Health Ministry, though some reports say 323 cases) in India fall in this category.
Stage 3: Community transmission: The source of the infection cannot be located because several areas now have been affected. A person tests positive despite no known exposure to an infected person nor any history of travelling to an infected area. Italy, Iran and Spain are in this category now.
Stage 4: Epidemic or pandemic, which is an outbreak so severe with no clear end point for the ongoing transmission. China is in currently in the decline of this stage, and in the Wuhan region there have been no new cases for several days.
Stage 2 Testing
Till Mar 21, the ICMR guidelines for testing covered only travelers and their contacts who had symptoms. The others are not tested but quarantined.
On Mar 21, the criteria for testing further included hospitalised individuals with severe respiratory illness (fever and cough/shortness of breath), and high-risk contacts without symptoms, of a confirmed case. These contacts are to be tested between days 5-14 after contact.
So the numbers tested so far remain small. Graphs in the media that claim India is behind other countries in testing are comparing apples and oranges. Countries in Stage 3-4 will evidently need to test more people. An interview in The Hindu with a virologist quoted him as saying that “everyone should be tested for infection”. This is irresponsible. The gentleman may be an eminent lab scientist, but he is not a public health epidemiologist.
Even if it was needed, it is not possible to test everyone, even in a country like the US. The required number of test kits, labs, and qualified personnel are not available. The probes needed to detect RNA/DNA in the test have to be imported and the ICMR has ordered one million recently. Each test, though done free, costs Rs 4500.
As of Mar 21, ICMR has tested 17,701 samples with 271 as positive. A scientifically-determined sample number of tests done in the general population in the country are all negative, confirming that community transmission from unknown sources has not yet occurred.
The ICMR network of 79 labs are so far working at 10% capacity. The inclusion of private labs is being pursued and set in place, so if needed, testing can be upscaled.
Stage 2 Measures
The appropriate measure for containment in a Stage 2 situation is Mitigation: slowing epidemic spread. Mitigation can be achieved by home isolation of suspect cases, home quarantine of those living in the same household as suspect cases, and social distancing. So far the positive cases and suspect cases are all directly or indirectly related to foreign travelers.
The other strategy is Suppression: reversing epidemic spread, reducing case numbers to low levels and maintaining that situation till a vaccine is available. This is required for Stage 3, though some suppression measures may help to forestall Stage 3.
Partial suppression will require a combination of school and university closures, social distancing, home isolation of cases and household quarantine of their family members. Total suppression (required for Stage 3) entails complete social contact shutdown, including stoppages of work and closure of all commercial establishments, except of course for essential services.
The aim of suppression is to reduce the transmission number R (the number of new cases each case generates) to below 1.
The Stages in China
The Wuhan experience has been studied in detail by international scientists, and a cluster of studies have already been published in prestigious journals such as Nature. The four stages have been tracked and also the post-epidemic decline in new cases, up to zero.
The epidemic began on Dec 1, 2019, peaked on Feb 16, 2020, with a rapid decline thereafter. As of Mar 16, 2020, only 110 ‘old’ cases are under treatment and the R number is 0.5. In other words, the ‘active’ phase of the epidemic lasted about two and a half months. Wuhan, with its 11 million population, is now being restored to normalcy.
The policies and measures being followed by the Government of India seem appropriate for Stage 2 and are intended to contain the situation at this stage and forestall progression to Stage 3.
State governments need to follow the lead of the central government, though some local measures may also be appropriate.
For example, in Bangalore, 500 two-member teams, consisting of a health worker and a constable are visiting the homes of all foreign returnees from high risk countries, to ensure they are in quarantine. Bangalore has about 43 thousand such individuals, and Kerala has 53 thousand. In Meghalaya the individuals being registered are domestic travelers so an online monitoring system is suitable.