How Does Coronavirus Spread? We Explain The Basics

A single patient with coronavirus infected at least 10 healthcare workers and four patients at a hospital in Wuhan, China, according to a study , which shows just how fast – and easily – the virus can spread.

The study’s authors estimate that, on average, each patient in the hospital had spread the infection to at least two other people. Meanwhile on home soil, a British man who became infected in Singapore is thought to be responsible for at least seven other confirmed cases in England, France and Spain.

The latest type of coronavirus – known as 2019 Novel Coronavirus (2019-nCoV) – is one of seven types of coronavirus identified since the mid 1960s. There are four common human coronaviruses, where the symptoms tend to be less problematic. These are 229E, NL63, OC43 and HKU1. 

There are also types of coronavirus that originated in animals and evolved to impact humans. These include: MERS-CoV (coronavirus that causes Middle East Respiratory Syndrome, or MERS), SARS-CoV (coronavirus that causes severe acute respiratory syndrome, or SARS), and most recently, 2019 Novel Coronavirus (2019-nCoV).

So how do these viruses spread?

With previous outbreaks like MERS and SARS, human-to-human transmission occurred through droplets (i.e. when you cough and sneeze), contact with others, and touching infected objects or materials.

Paul Hunter, a professor in medicine at University of East Anglia, reiterates this, telling HuffPost UK coronaviruses are spread largely by droplets in the air. As the old saying goes: “Coughs and sneezes spread diseases.”

If a person with coronavirus coughs or sneezes and another person is within two metres of where they’re standing, they could inhale infected droplets. Likewise, if an infected person coughs or sneezes onto their hand, then touches a door handle, another person who touches that door handle could pick up the virus.

If an uninfected person touches these surfaces, then washes their hands immediately (and properly), there wouldn’t necessarily be a problem. But if they go on to touch their eyes, nose or mouth, they can become infected with the virus. In fact, touching anywhere near the mouth – for example, smoking – could cause infection, says Prof Hunter.

“That’s how colds spread [and how] SARS spread,” he says. “It is undoubtedly the primary way 2019 Novel Coronavirus spreads.”

Dr Nick Phin, deputy director of the National Infection Service at Public Health England (PHE) echoes this, adding: “While not a lot is known about the novel coronavirus, it is likely to behave in a similar way to other respiratory viruses.”

It’s unclear how long surfaces are contaminated for after an infected person has touched it – although under most circumstances, PHE says the amount of infectious virus is likely to have decreased significantly by 24 hours, and even more so by 48 hours.

Dr Phin says how long any respiratory virus survives will depend on a number of factors: “For example, what the virus is on, whether it is exposed to sunlight, differences in temperature and humidity, and exposure to cleaning products – even simple ones like soapy water and household cleaning sprays.”

Experts don’t currently know whether people without symptoms of coronavirus – but who are infected with the virus – are infectious or not. “If it’s only symptomatic people who spread the virus, you don’t need to worry too much about quarantining asymptomatic people [a person showing no symptoms],” says Prof Hunter. 

But, as we don’t yet know at what stage the virus spreads, it’s important to take whatever precaution you can by continuing to maintain good hygiene. 

The best way to stop germs spreading is to: avoid close contact with people (particularly those suffering from respiratory infection symptoms); frequently wash your hands with soap and warm water (or using sanitiser gel); and cough or sneeze into tissues, and then bin those tissues. This advice is useful for all winter viruses that may be circulating – not just for protecting against coronavirus. 

If the 2019 Novel Coronavirus does turn into a pandemic, this advice might change, Prof Hunter notes.