'New model finds countries should work together to control COVID-19'

Countries looking to contain the spread of diseases like COVID-19 should work together in multiple hotspots, according to a mathematical model developed by scientists.

Researchers at the Arizona State University (ASU) in the US said because it would be difficult to completely eliminate the novel coronavirus, countries should focus on keeping the rate of infection low by collaborating in multiple areas.

However, a clear division of labour may be called for in some circumstances, they said.

The model is intended to guide policymakers responding to the outbreak of harmful species, including pests, parasites and even infectious diseases like COVID-19, according to the study published in the journal PNAS.

It indicates that sometimes a "divide and conquer" approach is better, while in other situations it is more effective to work together in several locations, the researchers said.

A key question, they noted, is whether to focus on eliminating the harmful species entirely or controlling its spread to prevent the next outbreak.

"If you want to eradicate the harmful species, or reduce its abundance rapidly, then you may want to split the duties of the agents," said Adam Lampert, an assistant professor at ASU.

"If you want to control it, and keep it at a low level for prolonged periods, then working together becomes important," Lampert said.

He identified three factors to determine if the species should be controlled or eradicated: the annual cost of maintaining the population, the natural growth rate of the harmful species, and its response to the treatment.

Given the ongoing spread of novel coronavirus, Lampert said that we are seeing a mix of blanketed and targeted control efforts.

"With diseases, you can put a lockdown on the entire country, or a region, and say 'ok nobody goes out', and this way you reduce the infection level over time," he said.

"Or you can do some more targeted actions by identifying the people who are sick -- and keep them at home," Lampert said.

His research indicates that effective long-term control methods to reduce the spread of harmful species, including the novel coronavirus, require international cooperation.

Lampert says it is unlikely that we will be able to completely eradicate the virus, but controlling the spread is necessary for our social welfare, and can be accomplished most effectively if countries work together.

Lampert is already working on additional research applying these findings to COVID-19, specifically.