Aetiological diagnosis of acute respiratory illness in patients under investigation for the novel corona virus (SARS-CoV-2) before major Covid-19 outbreak in India

ABSTRACT

Background:The first case of COVID-19 was reported in India on 30th January 2020 with origin from China (PIB 2020, ‘https// pib.gov.in/pressreleaseiframepage.aspx?prid=1601095’). As on 6th May 2020 the total cases reported in India are 35,043, with 8,889 recoveries and 1,147 deaths (https//www.mohfw.gov.in/ accessed on 6th may at 1254 PM). However, the rate of infection is lower as compared to other countries. Since the Covid-19 pandemic started spreading in world outside China including India and large scale testing for Covid-19 became available, all the focus suddenly shifted to Covid-19. Other respiratory viruses, which were in existence for many years and testing and management of these infection was always standard of care, started getting neglected. Hence, we analysed the retrospective laboratory results from cases of acute respiratory infection, tested in the month of February 2020, when Covid-19 cases in India were close to negligible. This is to focus on need of testing for other respiratory viruses along with Covid-19 so that these infections can be managed as per standard protocol and do not get neglected in the wake of pandemic. Methods:The Virus research and diagnostic laboratory at Department of Microbiology, King George’s Medical University (VRDL) start- ed testing for Covid-19 on 3rd February 2020. This laboratory routinely tests all patients presenting as Severe Acute Respiratory Ill- ness (SARI) for 12 respiratory viruses including Influenza (Inf) A (both H1N1 and H3N2) and B, Adenovirus (ADV), Respiratory syntitial virus (RSV), Parainfluenza (Parainf) viruses 1, 2, 3 and 4, Measles virus (MEV), Bocavirus, Human metapneumo virus (HMPV) and Rhi- noviruses (Rhino). All patients presenting as Influenza like illness (ILI) are routinely tested for Influenza A and B viruses. If they test negative, other viruses are tested depending on clinical suspicion. The testing is routinely done as per methods described earlier (Singh A.K., Jain A., Jain B., Singh K.P., Dangi T., Mohan M. Viral aetiology of acute lower respiratory tract illness in hospitalised paedi- atric patients of a tertiary hospital one year prospective study Indian J Med Microbial. 2014;3213–18). Results:During February 2020, we tested 316 cases of SARI/ ILI for covid-19. None of them tested positive for Covid-19. Samples from these cases were also tested for other respiratory viruses as mentioned above. Total 10 (3.2%, 8 H1N1 (2.5%) and 2 H3N2 (0.6%)) samples tested positive for Influenza A, 2 each tested positive for Influenza B, HMPV and Adenoviruses. One sample each tested posi- tive for RSV and Rhinoviruses. Total 5 samples tested positive for parainfluenza viruses;3 for parainfluenza 1, and 1 each for parain- fluenza 1 and 4 Conclusions:( table). The positivity for covid-19 in India in pandemic time remains less than 4% (https//www.mohfw.gov.in/ ac- cessed on 06 May 2020, 0800 IST), while the positivity for rest of the respiratory viruses as shown in present analysis is 7.3%. It is essential to see that infection with other respiratory viruses does not get neglected and add to the Covid-19 misery.