With community transmission now being confirmed in 36 districts, an expansion and change in testing strategy becomes imperative in the high focus areas for the lockdown to be more successful and meaningful and to prevent the virus spread from spiralling out of control.
Even after the Health Ministry on March 28 acknowledged on its website that there was “limited community transmission”, India’s national taskforce for COVID-19 continues to deny it. Now, a paper published on April 9 in the Indian Journal of Medical Research by the Indian Council of Medical Research and Health Ministry researchers, who are members of the task force, provides evidence of community transmission in 36 districts in 15 States.
The study is based on sentinel surveillance undertaken by the taskforce among severe acute respiratory illness (SARI) patients who have been hospitalised in public sector institutions to identify the spread and the extent of transmission of COVID-19 disease in the community.
Taskforce long aware of community spread
If there were 1.9% (two of 106) SARI cases positive for novel coronavirus (SARS-CoV-2) by the end of March third week, the number increased to 104 by April 2. These people neither had any history of international travel or known contact with a positive person. Of the 102 coronavirus positive SARI cases tested between March 22 and April 2, 40 (39%) had no travel history or contact with a positive case; data on exposure were not available for 59 (58%) cases.
If more than 1% of SARI patients tested positive for the virus in 15 States, at 21 (3.8%) Maharashtra had the most number of coronavirus positive SARI cases in eight districts followed by Delhi (14 cases; 5.1%), Gujarat (13 cases; 1.6%), and West Bengal (9 cases; 3.5%). In comparison, Kerala had just one SARI patient testing positive for the virus.
The authors point out that antibody-based testing carried out in those testing negative for molecular test, given that it throws up false negatives, could have helped identify more positive cases.
Change in testing strategy
With community transmission now being confirmed in 36 districts, an expansion and change in testing strategy has become imperative in the high focus areas for the lockdown to be more successful and meaningful and to prevent the virus spread from spiralling out of control.
Though the taskforce has not openly declared community transmission, it is reassuring to note that the ICMR has already initiated changes in the testing strategy in response to the pattern of virus spread in the community. On April 9, ICMR revised the testing strategy for hotspots/clusters and large migration gatherings/evacuees centres. While the criteria for testing people across India remain the same, the testing norms for the high focus areas will now include people with influenza-like illness (ILI) with certain symptoms.
Focus on hotspots
It is imperative that private hospitals in the high focus areas test all SARI and ILI patients while more public sector hospitals follow suit. Also, antibody testing should be carried out whenever molecular tests on these patients turn out negative. It is important to include antibody testing along with molecular testing when necessary in the high focus areas. Together with containment measures, this approach will greatly help in snapping the transmission chain.
Syndromic surveillance of all SARI and ILI patients along with quick and effective tracing, quarantining and testing of their contacts should be the way forward now to contain the spread. How well India responds now will determine whether the spread is contained or lead to more cases and deaths.
Science Chronicle 