Journal of Patient Safety and Infection Control

: 2021  |  Volume : 9  |  Issue : 2  |  Page : 60--61

Nature - The great leveller: It is a way to end the COVID era?

Raman Sardana1, Leena Mendiratta2, Hena Butta3,  
1 Hospital Infection Society, India
2 IEC, AHERF Indraprastha Apollo Hospitals, New Delhi, India
3 Department of Microbiology, Indraprastha Apollo Hospitals, New Delhi, India

Correspondence Address:
Dr. Hena Butta
Department of Microbiology, Indraprastha Apollo Hospitals, New Delhi

How to cite this article:
Sardana R, Mendiratta L, Butta H. Nature - The great leveller: It is a way to end the COVID era?.J Patient Saf Infect Control 2021;9:60-61

How to cite this URL:
Sardana R, Mendiratta L, Butta H. Nature - The great leveller: It is a way to end the COVID era?. J Patient Saf Infect Control [serial online] 2021 [cited 2022 Jun 30 ];9:60-61
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Full Text

In August 2021, we are seeing a surge in influenza cases (influenza A, influenza A H1N1 2009 and influenza B) in our geographical area in India. Hence, we looked into the data of influenza cases at our tertiary healthcare set-up from March 2019 to August 2021 [Figure 1]. We found similar surge of influenza cases in 2019 in August and September. However, in August 2020, cases of influenza were very minimal in number. Moreover, the surge of influenza cases was observed in March 2019 and February–March 2020 but not in March 2021. It shows the seasonal occurrence of influenza virus in these months. There are many co-circulating viruses that inhabit human respiratory tract and may cause acute respiratory tract infections. The dynamics of type of virus causing infection depends upon virus–virus interactions. Existence of interactions amongst respiratory viruses and virus competition is a known phenomenon and has been reported earlier.[1] It has been proposed by various scholars that the less frequent occurrence of influenza in the last year may be due to good hygienic practices, social distancing, lockdown, antiviral defence provided by SARS CoV-2 in the respiratory tract and lesser diagnostic test for influenza virus. We strongly believe that such pattern of occurrence of influenza virus in the last 2½ years is due to its interaction with SARS CoV-2. Last year in these months, SARS CoV-2 would be outcompeting influenza virus, maybe due to its novel characteristics, higher virulence, more transmissibility and less antibodies levels in human beings. At present, we are seeing a declining trend of SARS CoV-2 from the last 2 months, and the sero-surveillance data have shown occurrence of antibodies against SARS CoV-2 in 68% of the population.[2] However, now, its influenza virus turns to outcompete SARS CoV-2. The various mechanisms of virus interactions amongst themselves include interference, i.e. one virus blocking entry of other through common entry receptors, viruses competing for host cell resources and cross-protection through immune response.[3] The entry receptors for influenza (sialic acid receptors) and SARS CoV-2 (angiotensin-converting enzyme 2) are different.[4] Hence, the main interaction between these two viruses is based upon host cells' resources, innate and acquired immunity of the host against particular virus and antigenic changes in the viruses.{Figure 1}

The sharp decline in influenza cases during SARS CoV-2 pandemic was noticed across the world, and the main cause was proposed to be COVID mitigation measures.[5] The complacent behaviour of the people, due to decline in COVID cases and a drop in flu and other vaccinations globally, may also be leading to the rise in cases of influenza and other respiratory viral illnesses. We strongly recommend the COVID appropriate behaviour for the mitigation of both COVID and influenza and influenza-like illness.

This rise in cases of influenza may be a good sign as it is going by seasonality-like earlier years before COVID-19 pandemic. It also goes by law of nature to balance itself and thus gives a ray of hope that SARS CoV-2 virus would epidemiologically behave like its predecessor coronaviruses (human coronavirus 229 E, NL63, OC43, HKU1) circulating for many years amongst human global population, competing with other coronaviruses causing mild cold–cough illness or facing competition from other respiratory viruses causing influenza and influenza-like illnesses in global population.

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Conflicts of interest

There are no conflicts of interest.


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