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Will COVID-19 die down in summer? New tests could help answer that.

Stylized SEM of the SARS coronavirus.
(Image: © MedicalRF.com/Getty Images)

Empty, mocked-up shells of the new coronavirus, SARS-CoV-2, may help explain how well the virus stands up to heat, humidity and other environmental changes. 

The research, just launched by physicists at The University of Utah, is designed to help public health officials understand how the new coronavirus will react as the seasons change. One major question about the virus, which causes a disease called COVID-19, is whether summer will do anything to slow the spread. 

Related: How does the new coronavirus compare with the flu?

"Coronavirus spreads similarly to the influenza virus — as small mucus droplets suspended in the air … Viruses lose infectivity because the particles lose structural integrity," University of Utah physicist Saveez Saffarian said in a statement. "The physics of how the droplets evolve in different temperature and humidity conditions affect how infectious it is."

Along with physicist Michael Vershinin, Saffarian has just received a nearly $200,000 National Science Foundation (NSF) grant to study how the virus's protective outer shell responds to changes in heat and humidity. Viruses are not able to "do anything" on their own, as they are simply shells with genetic instructions tucked inside; when a virus invades a host's cells, it uses that cell's machinery to replicate itself, over and over again.

Related: 13 Coronavirus myths busted by science

The research involves working with dummy versions of the virus's protective outer shell. Using the sequenced genome of SARS-CoV-2, the researchers are building synthetic versions of these shells, with no viral genomes inside. This makes the shells uninfectious and safe to work with. 

"We're making a faithful replica of the virus packaging that holds everything together," Vershinin said in the statement. "The idea is to figure out what makes this virus fall apart, what makes it tick, what makes it die."

To manipulate the nano-sized dummy particles, Vershinin's lab uses a tool called optical tweezers — essentially, focused beams of light. The light's energy can be directed to move and probe individual molecules. Saffarian studies RNA viruses on a broader scale and is an expert in lab techniques that can track individual viral particles. 

The researchers said they hope to find out how well the virus will transmit in different conditions, from outdoors in summer heat to indoors in air-conditioned offices. This could influence how long social distancing and lockdown policies will need to be in place. 

"This is not a vaccine," Vershinin said. "It won't solve the crisis, but it will hopefully inform policy decisions going forward."

Originally published on Live Science.

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  • tomrobey
    Is it a change of seasons that may affect things? I'm curious because they have numerous confirmed cases south of the equator, where countries have opposite seasons of ours; so they just went from summer into fall recently, and the virus seems active in those hotter conditions.
    Reply
  • Vivek
    If Covid-19 can come down in summer why wait for summer. The common hair dryer can also produce the same temparature of around 60-70 degree centigrade.
    Reply
  • DeusExMachina
    Vivek said:
    If Covid-19 can come down in summer why wait for summer. The common hair dryer can also produce the same temparature of around 60-70 degree centigrade.
    Because first of all, that's not how it works, and second, unless you plan on severely burning your sinus passages, trachea, lungs and alveoli, you aren't going to accomplish anything.
    Reply
  • DeusExMachina
    tomrobey said:
    Is it a change of seasons that may affect things? I'm curious because they have numerous confirmed cases south of the equator, where countries have opposite seasons of ours; so they just went from summer into fall recently, and the virus seems active in those hotter conditions.
    No.
    Reply
  • DeusExMachina
    This experiment completely misunderstands the issue of transmission vectors and how they are affected by temperature.
    Aerosolizaton and droplet size and spread at different temperatures have literally nothing to do with increased transmission.
    Respiratory viruses spread more readily in colder months because the viruses rely on the body's response to cold as a transmission vector. Mucous membranes, relative to skin, are much more susceptible to freezing as the temperature drops. To counter this, these membranes, such as that line the nose, mouth, and throat, secrete liquids: saliva, mucous, etc., to increase surface energy and thus decrease rate of freezing of tissues. This is why your nose runs in the cold, regardless of whether or not you are sick. It runs to prevent your sinuses from freezing solid, and thus dying.
    Viruses capitalize on this by riding the waves of mucous out of their current host and into another. Likewise, they reply on the need to wipe these secretions away to hitch a ride on hands and other surfaces to move to a new host.
    For viruses that rely on these mechanisms, cold weather increases transmission rate, not due to the physical properties of the droplets, but the physiological response of the body itself.
    Reply
  • GEO030479
    DeusExMachina said:
    This experiment completely misunderstands the issue of transmission vectors and how they are affected by temperature.
    Aerosolizaton and droplet size and spread at different temperatures have literally nothing to do with increased transmission.
    Respiratory viruses spread more readily in colder months because the viruses rely on the body's response to cold as a transmission vector. Mucous membranes, relative to skin, are much more susceptible to freezing as the temperature drops. To counter this, these membranes, such as that line the nose, mouth, and throat, secrete liquids: saliva, mucous, etc., to increase surface energy and thus decrease rate of freezing of tissues. This is why your nose runs in the cold, regardless of whether or not you are sick. It runs to prevent your sinuses from freezing solid, and thus dying.
    Viruses capitalize on this by riding the waves of mucous out of their current host and into another. Likewise, they reply on the need to wipe these secretions away to hitch a ride on hands and other surfaces to move to a new host.
    For viruses that rely on these mechanisms, cold weather increases transmission rate, not due to the physical properties of the droplets, but the physiological response of the body itself.
    Recently read a study on Dramatic 2015 excess mortality in Italy a 9.1 increase that needs to be explained. Now the numbers on the report almost mirror the numbers infection mortality rate that are coming out of Italy recently. Could there be any correlation between the two, as far as undetected previous outbreaks of Covid19 in parts of Italy. The report specifically refer to north Italy as most affected which from my understanding thats the region most affected in the current epidemic.
    Reply
  • Janini
    tomrobey said:
    Is it a change of seasons that may affect things? I'm curious because they have numerous confirmed cases south of the equator, where countries have opposite seasons of ours; so they just went from summer into fall recently, and the virus seems active in those hotter conditions.
    Very valid question. Because here in the Philippines is almost always summer these days, really warm. But this fact has not prevented the COVID from spreading here. And isn't Italy a summery place and yet has the highest mortality rate from COVID.
    Reply
  • Janini
    DeusExMachina said:
    Because first of all, that's not how it works, and second, unless you plan on severely burning your sinus passages, trachea, lungs and alveoli, you aren't going to accomplish anything.
    I think the point she is trying to make is that maybe we can create the same temperature requirement to destroy the virus via artificial way (e.g. increase radiator temperature) that is when and if the medical experts do find out if environmental temperatures can weaken the integral structures of these microscopic demons enough to kill them.
    Reply