As countries start lifting curbs imposed on societies due to the COVID-19 pandemic, news reports have indicated higher rates of respiratory infections, even unseasonal diseases such as influenza and the respiratory syncytial virus (RSV).

Doctors have called this the “immunity debt” brought on by non-pharmaceutical interventions (NPIs) put in place to reduce the spread of the SARS-CoV-2 virus.

What caused ‘immunity debt’?

The NPIs, including social distancing, use of masks, and hand hygiene, were seen as being effective in breaking the chain of transmission of the SARS-CoV-2.

During the pandemic, they have been employed to do exactly that, and have succeeded at varying levels in countries, depending on the level of compliance.

• However, they have had unintended consequences for other respiratory infections as well.
• America is among the nations seeing an increase in the number of RSV cases in the infant population.
• Non-pharmaceutical interventions (NPIs) have been employed to reduce the transmission of ‘Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)’ yet these measures are already having similar effects on other directly transmitted, endemic diseases.
• Disruptions to the seasonal transmission patterns of these diseases may have consequences for the timing and severity of future outbreaks.

Is the impact only on respiratory viruses (RSV) or on other viruses as well?

• RSV can be severe in very young infants, but it is commonly a winter infection.
• Babies gain some protection from mothers, but the mother must have had some exposure to the virus.
• If mothers are not exposed, it leaves the baby unprotected, and if it is not very severe, children can be supported through the infection.
• A monoclonal antibody is used to treat RSV. In adults, an outbreak of seasonal influenza is expected.

Rethink on lockdowns:

Despite the huge social and economic costs, lockdowns and social distancing have shown demonstrable success in containing the pandemic.

• The Nature Communications article calls for a reassessment of the role of NPIs and an analysis to identify the most effective components to prevent respiratory virus transmission and infection.
• This might yield “new and sustainable interventions that can minimise and prevent seasonal and epidemic respiratory viral illnesses in the future”.

Source: The Hindu