More than 40% of people with coronavirus are asymptomatic, suggesting the virus may be far more widespread than the CDC's latest estimates

Nearly half of all cases of the novel coronavirus may be asymptomatic, a new study suggests.

Researchers found that more than 40 percent of patients didn't experience a cough, a fever or difficulty breathing.

These patients were more likely to be younger, female, and have much less damage to organs such as the lung and liver. 

Previously, the director of the Centers for Disease Control and Prevention, Dr Robert Redfield, estimated that one in four patients are asymptomatic. 

The team, from Zhongnan Hospital in Wuhan, China - where the worldwide outbreak originated - says its new findings are evidence that the highly-infectious virus may be more widespread than previously believed.

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Researchers looked at 78 coronavirus patients from Wuhan, China, and found that 33 - more than 42% - are asymptomatic. Pictured: A customer wearing a protective mask tries on a pair of shoes at Sundance Shoes in Birmingham, Michigan, May 27

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Asymptomatic patients tended to be younger (in their 20s to 40s), women and had less damage to their organs. Pictured: Nurse Paula Johnson administers a deep suction tube into the lungs of a coronavirus patient, in the ICU at Roseland Community Hospital in Chicago, Illinois, April 22

For the study, published in JAMA Network Open, the team looked at 78 patients who tested positive for the virus from December 24, 2019 to February 24, 2020.

They found that 45 patients were symptomatic with signs such as a dry cough, fever, fatigue and shortness of breath. 

However, 33 patients - more than 42 percent - were asymptomatic, meaning they didn't exhibit any of those signs.

Asymptomatic patients were more likely to be younger ranging from their late 20s to their early 40s, while symptomatic patients ranged from their mid-30s to early 60s.

Females also tended to show no signs of the virus with nearly 67 percent of the asymptomatic group made of women compared to 31 percent of the symptomatic group.

In addition, the group of asymptomatic patients had a 'lower proportion of liver injuries' and had a faster lung recovery at about nine days in comparison with 15 days. 

'Our finding...suggests that damage to the immune system in asymptomatic infections was milder compared with symptomatic infections,' the authors wrote. 

Researchers noted that because asymptomatic patients may be unaware of their disease, they likely didn't isolate themselves or seek medical are and, thus, spread the disease to others.

But, fortunately, asymptomatic patients tended to shed the virus for half as long, eight days in comparison with 19 days.  

'Since patients with asymptomatic COVID-19 were relatively concealed, the fact of viral shedding detected via nasopharyngeal swabs must not be ignored,' they wrote.

'Therefore, identifying and isolating patients with asymptomatic COVID-19 as early as possible is critical to control the transmission of COVID-19.'

The team also suggests identifying close contact of coronavirus patients and monitoring them to avoid secondary transmission.   

The findings come on the heels of another study, conducted by Australian researchers, that looked at passengers on a 21-day Antarctic cruise earlier this year.

Of the 217 passengers and crew members, 128 tested positive for the virus and an astonishingly high 81 percent did not have symptoms.