Indian Journal of Medical Specialities

: 2021  |  Volume : 12  |  Issue : 1  |  Page : 48--49

The impact of COVID-19 preventive measures on the spread of influenza viruses and influenza-like illnesses

Chidiebere Emmanuel Okechukwu 
 Department of Public Health and Infectious Diseases, Sapienza University of Rome, Piazzale Aldo Moro 5, Rome, Italy

Correspondence Address:
Dr. Chidiebere Emmanuel Okechukwu
Department of Public Health and Infectious Diseases, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome

How to cite this article:
Okechukwu CE. The impact of COVID-19 preventive measures on the spread of influenza viruses and influenza-like illnesses.Indian J Med Spec 2021;12:48-49

How to cite this URL:
Okechukwu CE. The impact of COVID-19 preventive measures on the spread of influenza viruses and influenza-like illnesses. Indian J Med Spec [serial online] 2021 [cited 2023 Jan 30 ];12:48-49
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Full Text

Dear Editor,

Respiratory viruses such as influenza viruses are spread through droplets and particle aerosols from the coughs and sneezes of infected people and through contact with surfaces that have been infected.[1] Apart from receiving an influenza vaccine, the use of face mask, and observing hand hygiene are important measures for preventing influenza contagion.[1] The mandatory use of face mask, hand sanitizer, and strict observance of social distancing were among the measures that were specified to curtail the spread of coronavirus disease 2019 (COVID-19), and these measures are actually useful for the prevention of other viral respiratory diseases.[2] There was a significant decline in the spread of? influenza-like illnesses in the first half of 2020 when compared to the last 3 years in Singapore, signifying that the actions taken against the COVID-19 pandemic in 2020 were useful in reducing the spread of other viral respiratory diseases in the country.[3] Moreover, a significant decrease in hospital admissions was seen for both noninfluenza respiratory viruses and influenza viruses, and the number of intensive care unit admissions for respiratory viruses also reduced in Singapore.[4] Data from almost 300 medical laboratories in the United States of America (USA) situated in the 50 states of the USA, Puerto Rico, Guam, and the District of Columbia that partook in virologic surveillance for influenza either via the USA World Health Organization Joint laboratories network or the National Respiratory and Enteric Virus Surveillance System, showed that in the USA, influenza virus transmission declined abruptly within 2 weeks of the COVID-19 emergency announcement and extensive enactment of public mitigation measures, including school closures, social distancing, and wearing of face masks.[5]

The decline in the spread of influenza viruses in the USA also occurred in other Northern Hemisphere countries.[5] Subsequent to the extensive implementation of public prevention measures to decrease the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the percentage of USA respiratory specimens presented for influenza test which tested positive decreased from >20% to 2.3% and has lingered at historically low intersessional levels (0.2% vs. 1%–2%), statistics from Southern Hemisphere countries was not significant regarding influenza occurrence.[4] Measures designed to curtail SARS-CoV-2 transmission coupled with influenza vaccination could significantly decrease the prevalence and effect of influenza in the 2020 and 2021 winter season.[5] Moreover, the continuous observance of COVID-19 preventive measures would play a significant role in reducing influenza transmission in the Northern and Southern Hemisphere countries during the winter season to a minimum level.[5]

In conclusion, there is a need to sustain the extensive COVID-19 preventive measures such as the mandatory use of face masks, hand sanitizer, and observation of social distancing; this will significantly reduce the spread of influenza viruses and influenza-like illnesses, particularly in the Northern and Southern Hemisphere countries.

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Conflicts of interest

There are no conflicts of interest.


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2Galvin CJ, Li YJ, Malwade S, Syed-Abdul S. COVID-19 preventive measures showing an unintended decline in infectious diseases in Taiwan. Int J Infect Dis 2020;98:18-20.
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