The novel coronavirus might have been circulating in Italy far earlier than previously thought, according to a new study conducted by the National Cancer Institute in the Italian city of Milan.

The research findings, which were published in the science magazine Tumori Journal, revealed that the virus was likely already present in Milan last September—a full five months before the country’s first coronavirus-positive patient was detected and three months before the initial outbreak was reported in Wuhan, China.

In March, health officials and doctors reported a higher-than-average number of cases of severe pneumonia and influenza outside Milan in the last quarter of 2019, which could have been an early sign that the virus was already being transmitted by individuals in the region.

Italy’s first coronavirus patient was officially confirmed on February 21 in a small town near Milan, within the northern region of Lombardy.

The World Health Organization had previously stated that the novel coronavirus was not circulating elsewhere before Wuhan began implementing measures to contain the contagion.

In settling on the study’s surprising findings, the Italian researchers were able to verify that about 12 percent of 959 healthy volunteers enrolled in a lung cancer screening trial between September 2019 and March 2020 developed coronavirus antibodies long before the country’s first case was identified.

More specific coronavirus antibody tests were conducted by University of Siena, and what the researchers discovered was that four cases dated back to early October were also positive for antibodies—meaning that these individuals were likely infected in September.

“This is the main finding: People with no symptoms not only were positive after the serological tests but had also antibodies able to kill the virus,” the study’s co-author Giovanni Apolone told Reuters. “It means that the new coronavirus can circulate among the population for long and with a low rate of lethality not because it is disappearing but only to surge again.”

For Dr. Jill Foster, a professor at the University of Minnesota Medical School, she isn’t necessarily surprised that the study was able to confirm the expansive reach of the virus.

“This is a tipping-point virus that stealthily enters a population and then explodes. It is a virus hiding in plain sight but unseen. It starts first in a mobile population with a high number of social interactions—younger, healthier people who are in school, socializing, going to work, and traveling. One person gives it to two people who give it to two more and you have exponential spread, so that soon you have a hundred and then a thousand,” she told The National Interest.

“A high number of them are not going to have any symptoms or mild ones, so they continue their daily activities rather than staying home in bed. It continues to spread, and it becomes an odds game. Are you a vulnerable person who is elderly or with chronic health issues who interacts in a crowd of a hundred with only one person in the group infected or with fifty infected? Someone may have gotten away with mingling without a mask for months, but as the numbers climb, the minefield for the vulnerable becomes more dense,” she added.

Dr. Dean Winslow, an infectious disease specialist at Stanford Health Care, noted that it is certainly possible that the virus was circulating in September, but did offer one caveat.

“The study used an antibody test for SARS-CoV-2, which found a prevalence of 11.6 percent seropositivity in a cohort of 959 patients undergoing a lung cancer screening study,” he told TNI. “We know that antibody tests may often lack specificity, and it is possible that these seropositive patients had been previously infected with a different coronavirus and the positive results represented cross-reactivity.”

In May, a genetic study out of England suggested that the novel coronavirus was circulating around the world as early as October.

Scientists at University College London’s Genetics Institute were able to identify nearly two hundred recurrent genetic mutations of the coronavirus, which researchers said showed how the virus was adapting to its human hosts as it spreads.

“Phylogenetic estimates support that the COVID-2 pandemic started sometime around October 6, 2019 to December 11, 2019, which corresponds to the time of the host jump into humans,” the research team wrote in the journal Infection, Genetics and Evolution.

Ethen Kim Lieser is a Minneapolis-based Science and Tech Editor who has held posts at Google, The Korea Herald, Lincoln Journal Star, AsianWeek, and Arirang TV. Follow or contact him on LinkedIn.

Image: Reuters