Countries across the world have taken greater measures to combat COVID-19 than any other disease in living memory. Despite this, the disease is projected by some to become a yearly, seasonal condition.
Not since the Spanish flu that began more a century ago have we witnessed lockdown measures of the manner being witnessed today. COVID-19 has impacted lives across the globe, with many losing their homes, livelihoods, and indeed their lives to the disease and its resultant effects on the economy. It comes as bleak news that some experts believe that the disease may be here to stay.
A study, published in the journal Transboundary and Emerging Diseases, has reported an association between lower humidity and an increase in locally acquired COVID-19 cases. “COVID-19 is likely to be a seasonal disease that recurs in periods of lower humidity. We need to be thinking if it’s wintertime, it could be COVID-19 time,” said study author Professor Michael Ward of the University of Sydney in Australia.
There are biological factors at play that can increase infection rates under different climates. In the case of diseases spread by coughing and sneezing, cold weather typically increases infection rates. “When the humidity is lower, the air is drier and it makes the aerosols smaller. When you sneeze and cough those smaller infectious aerosols can stay suspended in the air for longer,” Ward said. “That increases the exposure for other people. When the air is humid and the aerosols are larger and heavier, they fall and hit surfaces quicker.
“This means we need to be careful coming into a dry winter. Ongoing testing and surveillance remain critical as we enter the winter months, when conditions may favour coronavirus spread.”
This research warrants further investigation into COVID-19 infection rates across both the northern and southern hemisphere as seasons change. The infection rate may reduce as the north goes into summer, though at the same time infection rates may increase in the southern hemisphere as winter begins. This could result in cases surging in countries such as Brazil, currently the world’s second largest hotspot with 558,237 total cases.
India is now facing the very real likelihood that community transmission is occurring. Following the announcement of 200,000 cases the country may never fully eradicate the disease should transmission continue to occur in rural communities and areas where healthcare infrastructure is all but non-existent.
The announcements by experts of community transmission in the country add credulity that the disease could become seasonal. It is all but impossible that the disease will be eradicated in India — or indeed most countries — within a year. Therefore, countries must be prepared for yearly increases similar to what is currently observed in diseases such as the flu.