More than half of coronavirus patients caught the virus from people with no symptoms

Researchers from the University College Dublin reviewed 17 different studies to understand how the coronavirus spread around the world and the study reveals startling information that more than half of coronavirus patients caught the virus from people with no symptoms at all. The findings suggest that between 33 per cent and 88 per cent of people down with coronavirus caught it from people they didn't even know were infected in the first place.

The researchers also raised concerns about governments across the world easing the lockdown and warned that asymptomatic carriers could further escalate the numbers adding more burden to the already stressed out health sector. The study also revealed that it takes an average of about six days before a person starts to show symptoms and might take around 14 days for the majority of the cases to turn positive.


Strict social distancing measures should be in place

The researchers stressed on the fact that governments should continue strict social distancing measures as people with no symptoms are a ticking bomb and things might get out of control if the lockdown is eventually eased or lifted. "Our work suggests that transmission of SARS-CoV-2 is most likely in the day before symptom onset, whereas estimates suggesting most pre-symptomatic transmission highlighted a mean transmission times almost 3 days before symptom onset."

The study further states that a substantial amount of pre-symptomatic transmission can occur and everyone is indeed at a high risk of contracting the virus. ''Despite the variation between estimates based on different studies, we highlight the consistent finding that a substantial amount of pre-symptomatic transmission can occur. In absence of active surveillance, infectious people without symptoms may not be quarantined, and therefore may have more contacts with susceptible people resulting in increased COVID-19 transmission.''

The importance of staying home

The researchers revealed that it is very important for people to stay home even if the lockdown is eased as the potential to transfer the virus to people with a weaker immune system is at an all time high. ''Quantifying the transmission potential of Covid-19 before or in the absence of symptoms will inform disease control measures and predictions of epidemic progression. We used a straightforward approach of simulating large numbers of samples from both the incubation period distribution from our meta-analysis."

The findings highlight the urgent need for extremely rapid and effective case detection, contact tracing and quarantine measures if strict social distancing measures are to be eased. Every country must begin testing their citizens even if they show no symptoms at all.

Related topics : Coronavirus