Glenn C Kharkongor
There have been denials, assertions and side-stepping about community transmission from various spokespersons and experts. The Indian Council of Medical Research (ICMR) has been consistently claiming that community transmission has not occurred. A few days ago, Chief Minister Conrad Sangma assured us that the state was taking steps to forestall community transmission. On June 13, Andhra had 222 new cases of which 186 were reported to be from “community transmission”, the media carefully using quotation marks.
ICMR Director General Balram Bhargava was asked at a media briefing on June 10, if India is in the community transmission phase, Bhargava skirted the question and said, “There is a heightened debate around this term community transmission. Having said that I think even WHO has not given a definition for it.” This was on the day that India registered its highest number, 9996 cases.
But Delhi Health Minister Satyendar Jain said last week that in half of the Covid cases, the source of infection was not known. The assessment of the Delhi administration points towards the “third stage of spread. If the transmission has reached a stage where the source can’t be identified, it is community spread, according to epidemiology,” Jain said. The health minister carefully added, however, that it was up to the Centre to declare whether the community transmission stage had been reached.
What is community transmission?
In leading up to an epidemic, WHO describes the stepwise scenarios of: no cases, sporadic cases, clusters of cases, community transmission, and country-wide transmission.
According to the ICMR, community transmission has occurred when the source of the infection cannot be located because multiple 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. The WHO says that community transmission “is evidenced by the inability to relate confirmed cases through chains of transmission for a large number of cases, or by increase in positive tests through sentinel sampling”.
A state of community spread implies that the virus is now circulating in the community, and can infect anyone. At this stage, it is theoretically possible for everyone to catch the infection.
What are the experts saying?
The denials of the Indian government mean that the country is still at Stage 2, which is local transmission. This occurs when family members, friends, neighbours or other close contacts, contract the virus from an infected person. The source of the transmission is known, contacts can be located, and appropriate measures such as testing, treatment and isolation, are taken.
Some leading physicians have disagreed with this assertion for months. Jayaprakash Muliyil, former professor of epidemiology at CMC Vellore and Member, Research Committee, National Taskforce for Covid, declared that spread by community transmission started in March itself. In the first week of April, India Today quoted the Director ofAIIMS, Dr Randeep Guleria as saying that Stage 3 had begun in some parts of the country.
In the last week of May, a joint statement by the Indian Public Health Association, Indian Association of Preventive and Social Medicine, and the Indian Association of Epidemiologists included this sentence: “It is unrealistic to expect that COVID-19 pandemic can be eliminated at this stage given that community transmission is already well-established across large sections or sub-populations in the country.”
A paper published in the Indian Journal of Medical Research (IJMR) on more than 40,000 positive cases recorded between January and April, conceded that the exposure (travel or contact) history of a large number of confirmed cases was missing. The IJMR is the official journal of the ICMR.
Why doesn’t the government say so?
In March itself, community transmission had been established in at least 12 countries in Africa, said the World Health Organization (WHO). These include Algeria, Senegal, South Africa, Burkina Faso, Cameroon, Ivory Coast, Democratic Republic of the Congo, Ethiopia, Gabon, Liberia, Nigeria and Rwanda.
Since then we haven’t heard much about community transmission. The National Health Service (NHS) of the UK has been unable to trace contacts of 33% of people with coronavirus in spite of a vigorous ‘Test and Trace’ strategy, but they don’t use the term ‘community transmission’. Other than India, few countries seem to stress the concept of community transmission.
It’s difficult to overhear what goes on behind the closed doors of the central Secretariat, so we can only speculate. Perhaps the government feels that to concede the fact of community transmission would be tantamount to saying the lockdown didn’t work. Or they may be criticised for not doing enough testing. Already there has been a misstep by Dr VK Paul, NITI Aayog member, who predicted in the last week of April that cases would decline to zero by May 16.
Once community transmission has occurred the public health strategy changes. Only minimal mitigation measures would be required, mostly dependent on responsible citizen behaviour. Like for the flu, those who get moderately or severely sick will be treated. The doctors will do Covid testing just to confirm the diagnosis. Public health strategies will be confined to surveillance, outbreak monitoring, and vaccination programs when the vaccine is ready. In the long term, tracking of seasonal surges and regional variations and their concomitant factors will round out the knowledge of the behaviour of the virus.
Is community transmission an important concept
While acknowledging the threat of community transmission, the president of the Public Health Foundation of India (PHFI), Dr K Srinath Reddy maintained we must first be clear about the definition. He advises applying it to local situations rather than to the country as a whole. Two categories of localised outbreaks are of concern.
The first are cases concentrated around entry points of foreign travellers, usually large cities. The second are clusters in overcrowded areas, especially slums. The priorities now are to contain the disease in these areas and to protect rural regions, because two-thirds of the population resides in the rural hinterlands. Reddy’s nuanced view takes a disaggregated view, rather than viewing the country as a whole.
What about Meghalaya?
The small number of cases indicate that community transmission has not occurred in the state. All the positive cases are seemingly traceable to their antecedents. Most of these in any case are asymptomatic or have mild disease and are containable at home.
Registering and monitoring incoming travellers needs to be continued. But testing at entry point needs to be done only for those with symptoms or those coming from the 13 cities with high case load as Himachal Pradesh has done. These cities as per the ICMR list are: Delhi, Mumbai, Chennai, Ahmedabad, Thane, Pune, Hyderabad, Gurugram, Chengalpattu, Jaipur, Jodhpur, Kolkata, and Indore. Others do not need entry point testing and should go straight to home quarantine.
As only asymptomatic travellers are allowed to travel, it is unlikely that many newly infected persons will test positive, because the virus load is small in the early stages. Already we have seen such instances in Meghalaya. Institutional quarantine should be reserved only for those with moderate symptoms and for individuals whose home situations are not optimal. In other countries individuals with mild-moderate symptoms are being managed at home. Meghalaya could adopt this approach.
The decisions of headmen in Meghalaya are inconsistent, with some localities mandating that returnees must go to institutional quarantine, even though home conditions are adequate. This is against the current guidelines. Forced institutional quarantine of negative and asymptomatic cases has its own problems of logistics, proper care and supervision, and possible spread of other diseases.
In Karnataka, persons who are in home quarantine are required to provide the names of two neighbours who will assist the tracking system to ensure compliance. In this way, citizen responsibility is combined with systemic monitoring. Public identification of positive cases is not required. This violates the principle of patient confidentiality and may encourage vigilante actions.