OCT 09, 2020 4:40 AM PDT

COVID-19 transmitted in a fractal nature

New research published under the title “Fractal signatures of the COVID-19 spread” in the journal Chaos, Solitons & Fractals proposes an epidemiological model that provides a more detailed description of how the virus is spreading in different countries and regions.

The model is based on the idea of fractals, which are never-ending patterns that create self-similar across different scales. Fractals, often seen in nature, appear in the spread of the virus that has wreaked havoc on the world in the last year, say the researchers. For instance, with transmission, an infected person initially passes the virus to relatively small group or people within direct contact. Then there is a break in transmission, soon after which we see the initial pattern repeated with the infected group transmits the virus to a larger group. This pattern continues consistently, explain the researchers.

This model aims to complement models typical of pandemic transmission tracing, like the SIR. The SIR, which stands for susceptible (S), infected (I), and removed (R), is based on the idea that a susceptible person can be infected, and an infected person will eventually be removed (either via immunization or death): the sum of this total number of individual remains constant throughout the evolution of the epidemic even as the numbers of individuals in each category shifts.

In a SIR model, we see a model where the curve representing the number of COVID-19 infected people rises sharply during the initial phase when the pathogen is spreading rapidly, peaks at maximum contamination, and slopes down more gently as contagion slows until there are no longer any infectious people. The researchers behind this study thought that this type of model was missing a key piece of the COVID-19 story.

“Although this model is a very useful tool to investigate the temporal evolution of the pandemic, it provides few insights into how contagion progresses spatially, which is key to the planning of social distancing programs that effectively protect people and at the same time reduce the socio-economic impact of the disease,” study author Airton Deppman, a professor in the University of São Paulo’s Physics Institute (IF-USP).

The fractal-based model aims to address that gap. In developing the model, the research team used data for China, the United States, and the state of São Paulo, testing their findings on data for São Paulo and Europe in order to explore spatial distribution.

“When you construct a graph crossing the number of infected people with the population and quantify the variables on a logarithmic scale on the x and y axes, the result is a straight line. This is typical of a fractal phenomenon, in which the same pattern is repeated at various scales,” Deppman explained.

“The model successfully described in great detail the temporal evolution of contagion. As a rule of thumb, the curve rises steeply at first, and this is followed by smaller peaks and troughs as the virus is transmitted from one area to the next.”

The team says their model can be used to determine when social-distancing and quarantine measures should begin and end. They say, based on the data, these decisions should be made on a region by region case, instead of for an entire state or country.

Sources: Chaos, Solitons & Fractals, Eureka Alert

About the Author
  • Kathryn is a curious world-traveller interested in the intersection between nature, culture, history, and people. She has worked for environmental education non-profits and is a Spanish/English interpreter.
You May Also Like
NOV 24, 2020
Chemistry & Physics
How long does COVID-19 stay on surfaces?
NOV 24, 2020
How long does COVID-19 stay on surfaces?
New research published today in Physics of Fluids explores the drying times of COVID-19 on different think liquid film s ...
DEC 18, 2020
Chemistry & Physics
New research on the physical dynamics of SARS-CoV-2 on surfaces
DEC 18, 2020
New research on the physical dynamics of SARS-CoV-2 on surfaces
New research published in Advanced Nano-Biomed Research contemplates the physical dynamics of SARS-CoV-2 on abiotic ...
JAN 20, 2021
Chemistry & Physics
Check out this anode-free, zinc-based battery
JAN 20, 2021
Check out this anode-free, zinc-based battery
It is at once imperative and urgent to develop batteries capable of storing large amounts of energy if we are to success ...
JAN 24, 2021
Chemistry & Physics
ALMA observations give insight into the formation of stars
JAN 24, 2021
ALMA observations give insight into the formation of stars
New research published in the journal Astronomy & Astrophysics gives new insight into the mystery behind how stars f ...
FEB 03, 2021
Microbiology
How Changing Shape Enables Bacteria to Avoid Antibiotics
FEB 03, 2021
How Changing Shape Enables Bacteria to Avoid Antibiotics
Bacteria are survivors, and they can find ways to get around stuff we use to kill them, like disinfectants and antibioti ...
FEB 09, 2021
Plants & Animals
Venus Flytraps Generate Magnetic Fields
FEB 09, 2021
Venus Flytraps Generate Magnetic Fields
The Venus flytrap (Dionaea muscipula) might be the most famous carnivorous plant; it can entice prey to land on its leaf ...
Loading Comments...