Social Distancing, Lockdown and the Wide Use of Mask; A Magic Solution or a Double-Edged Sword for Respiratory Viruses Epidemiology?

The use of non-pharmaceutical interventions (NPIs), such as social distancing, lockdowns and the massive use of masks, have not only largely prevented the spread of SARS-CoV-2, but also of other respiratory viruses such as influenza or respiratory syncytial virus (RSV). This decrease has been so high that, in most countries, the influenza and RSV epidemic has not occurred. Far from being a beneficial fact, this can be problematic, since the absence of circulation of certain pathogens can lead to a decrease in herd immunity against them. This can promote the rise of more serious, longer-lasting epidemics that start sooner. To alleviate the collateral effects that may occur due to the decrease in circulation of viruses such as influenza, it is necessary to increase the production of influenza vaccines, carry out mass vaccination campaigns and focus on vaccinating the main drivers of this virus, children.