BETA
This is a BETA experience. You may opt-out by clicking here

More From Forbes

Edit Story

Can A Spring Thaw Help To Reduce Spread Of The Coronavirus?

Following
This article is more than 4 years old.

We know that as temperatures begin to warm in March and early April, the flu season begins to wane.

But with COVID-19 spreading throughout the globe, will it also follow suit?

The short answer is that we don't truly know at this point, but we can look at previous outbreaks of coronavirus to generate some clues.

Of the many coronaviruses that exist in the family of coronaviruses, just seven affect humans. Four of these viruses cause mild cold-like symptoms, while the remaining three are more lethal and presumed to be transmitted from animals such as camels, civets or bats.

The hope that spring and summer could effectively end the potential for a pandemic is certainly attractive. Trump tweeted earlier this month, saying that China’s steps to contain the virus would be successful, “especially as the weather starts to warm.”

But, is there any truth to this, or science to back this up?

The answer is partly true. Viruses that cause influenza or mild coronaviruses that lead to cold-like symptoms, do tend to regress as temperatures warm up: they are seasonal in nature, and their natural history is that they dissipate.

That said, we we still don't know if COVID-19 will follow the same course. The data and models are not able to accurately predict how this virus will behave as the weather starts to warm up.

As of today, over 81,000 cases and 2,700 deaths have occurred in 34 different countries. The outbreak has spread to 6 of world’s 7 continents, except Antartica. Public health officials now warn that COVID-19 is on the cusp of officially becoming a pandemic. What’s now left to see is whether sustained transmission begins to develop outside of China.

Viruses- The Basics

So, what are viruses composed of? What are they made of that makes them so dangerous?

Viruses such as the flu or coronaviruses are composed of simple things: lipids (or fats) and proteins. Viruses can wreak havoc and destruction, but only if they have a “host”. The host (animal) is their lifeline for sustenance and how they can replicate or divide inside the body. However, once a virus leaves it host, it’s not that easy to survive, primarily due to environmental factors.

As a result of physical contact, viruses can be passed person to person, spread by droplets or aerosols, but they can also survive on hard surfaces or fabrics, potentially for many hours up to days. The composition of the surface determines how long the virus can survive and, in turn, how infectious it may be to others who come in contact with it. And soap and water or hand sanitizer can reduce the ability of a virus to survive and infect others, by destroying its outer proteins and lipid core.

Research into “seasonal” viruses has largely centered around the flu, which is more prevalent during the winter, with flu season generally beginning in October and lasting into March and even April. Close quarters, and colder temperatures may partly explain why transmission is more likely during wintertime, when people tend to stay indoors. But air temperature, along with humidity may also play a pivotal role.

We know that colder and drier air allows viruses to survive in the air or actually travel longer distances as they become airborne. Animal research published in 2007 using guinea pigs demonstrated that high temperatures, but especially high humidity, reduced the spread and replication of influenza. As the humidity continued to increase, the virus was not able to spread at all. The explanation is that warmer air retains more moisture, preventing airborne viruses’ ability to travel efficiently as they might in drier air. As the humidity climbs, the droplets in a cough or sneeze acquire a greater degree of moisture as they are expelled. As this occurs, they are too heavy to remain airborne, and fall to the ground, unable to survive.

Real-world studies have produced similar results as above, including some tropical locations that display more influenza during rainy season, when people also stay indoors.

What we believe is that lower humidity, which typically occurs during the winter, may impede the ability of the mucous in our nasal cavities to function optimally. The mucous functions to serve as a filter to trap and then expel viruses and bacteria. The normally thick, mucous becomes much thinner and less able to function as an effective barrier as a result of colder, drier air.

But the role of sunlight is also another aspect that helps to deter and destroy viruses, including coronaviruses. Sunlight, which is less prevalent in the wintertime, actually helps to destroy viruses that land on surfaces.

Ultraviolet (UV) light helps to clean or sterilize surfaces, by breaking down proteins, but ultimately attacking the molecular bonds in their building blocks: DNA and RNA. UV light is being used in hospitals to sterilize equipment due to its keen ability to kill bacteria and viruses. In fact, recent research has demonstrated that Far Ultraviolet-C light, or “far UVC” has the potential to reduce the transmission of airborne microbial diseases such as influenza and tuberculosis (TB).

Unfortunately, past research is not able to provide enough information at this point in time as to whether COVID-19 will display the same seasonal behavior as influenza and other benign coronaviruses.

But if we look at similar, more recent outbreaks—SARS and MERS—we may be able to get some clues. SARS, in fact, shares nearly 90 percent of its DNA with COVID-19.

SARS, which began in November, 2002, and ended in July, 2003, suggests it may be seasonal, but also may have been controlled by effective identification of persons, contact tracing and swift quarantines. (People with SARS were also quickly identified and quarantined when they began to develop symptoms, which is not always characteristic of COVID-19, due to the potential for asymptomatic transmission). The question is whether it (SARS) abated with warmer weather, or did effective containment and prevention approaches prevent its spread?

If we look at MERS, which began in September, 2012 in Saudi Arabia where the temperatures are quite high, what’s clear is that this virus was never completely contained, and we continue to see pockets of new infection emerge in areas of the Middle East such as Iran and the United Arab Emirates. It hasn't behaved in a way that suggests it displays seasonal variation.

We simply don't know it COVID-19 will display behavior similar to SARS or MERS. It’s a waiting game, leaving global uncertainty in financial markets and supply chain dynamics, with the ability to seriously disrupt the stability of the global community.

If it behaves like the flu, it may continue to wreak havoc in the southern hemisphere as the seasons begin to change. The reality is that much uncertainty remains. But, what we can do is continue to be vigilant in our efforts to contain this virus: quickly identify patients, isolate, trace contacts and quarantine.

The use of antivirals such as Remsdesivir (used to treat Ebola) may offer hope in treating patients with severe pneumonia and respiratory compromise, but also those with more moderate disease symptoms. Trials are currently underway to investigate this possibility. But the promise of an effective, large scale vaccine is at least 12-18 months away, even with promising technology using mRNA.








Follow me on Twitter or LinkedInCheck out my website