Question: Can you always tell if someone has Covid-19?
Fact: No. The virus that causes Covid-19 can be in someone’s body for up to 14 days before they show symptoms and some people will have such a mild case of the novel coronavirus that they might not have any symptoms.
Health experts have said one can still transmit Covid-19, even if they do not have any symptoms.
That is why it is important that everyone follows the recommended prevention advice, such as social distancing, wearing of facial masks and regularly washing their hands, even if they feel healthy.
The term used to define those that do not show Covid-19 symptoms is asymptomatic.
For example, one can live in a house with people with Covid-19 infection and show no symptoms, meaning they may be an asymptomatic case.
This is why self-isolating for the recommended 10-day period from last contact with someone with known infection is so important.
Usually or in most cases, people with Covid-19 have developed a wide range of symptoms, ranging from mild symptoms to severe illness.
Symptoms may appear from two to 14 days after exposure to the virus and anyone can have mild to severe symptoms.
Some of these symptoms of Covid-19 include fever or chills, cough, shortness of breath or difficulty breathing, fatigue, muscle or body aches, headache, new loss of taste or smell, sore throat, congestion or runny nose, nausea or vomiting and diarrhoea.
Due to these symptoms, some think they can spot who has Covid-19 but research indicates it is not as easy as that, as it will mislead people to focus only on those who show symptoms rather than taking steps to prevent spread of the virus.
According to the World Health Organisation (WHO) global research on Covid-19 continues to be conducted, including how the novel coronavirus is transmitted.
Current evidence suggests that most transmission occurs from symptomatic people through close contact with others.
Accordingly, most recommendations by WHO on personal protective measures (such as use of masks and physical distancing) are based on controlling transmission from symptomatic patients, including patients with mild symptoms who are not easy to identify early on.
Available evidence from contact tracing reported by countries suggests that asymptomatically infected individuals are much less likely to transmit the virus than those who develop symptoms.
A subset of studies and data shared by some countries on detailed cluster investigations and contact tracing activities have reported that asymptomatically-infected individuals are much less likely to transmit the virus than those who develop symptoms.
WHO says comprehensive studies on transmission from asymptomatic patients are difficult to conduct, as they require testing of large population cohorts and more data are needed to better understand and quantified the transmissibility of Covid-19.
The health agency is working with countries around the world, and global researchers, to gain better evidence-based understanding of the disease as a whole, including the role of asymptomatic patients in the transmission of the virus.