More than 7,690 people have so far been tested for coronavirus in the UK, with 19 confirmed cases in the country.
Schools and GP surgeries have closed, and England’s chief medical officer has warned that it is “only a matter of time” before the illness spreads further.
Public Health England is in charge of ensuring all possible measures to contain the potentially deadly infection are put in place. So when a patient returns a positive result, what do those on the frontline do next?
Information gathering
The first crucial step in preventing the spread of the virus is to piece together the exact movements of the infected patient following the onset of symptoms – a process known as contact tracing.
Where have they been? Who have they visited? Who are their family members, friends, work colleagues and acquaintances?
Carried out by experienced public health protection teams, this fact-finding mission allows experts to quickly reach as many people as possible to inform them they may also be at risk.
Risk assessment
Once a patient’s connections have been established, public health officials carry out an individual risk assessment on each person they are known to have had contact with.
Contacts will then be categorised as high risk or low risk.
Closely-connected people, such as family members or those who have spent a prolonged period in close proximity to the patient and are deemed high risk, may be asked to self-isolate for 14 days. They will also have a daily contact assessment of their health and will be tested for the virus.
Others who may have had more fleeting contact will be given advice on symptoms to look out for and what to do if they start to feel unwell, including emergency contact details.
Anyone who reports symptoms after exposure to the virus will be assessed and offered testing.
What counts as ‘close contact’?
“Close and sustained contact” means those who have been within two metres of a “confirmed clinical case” for 15 minutes or more.
Public Health England says those who have not been in close contact with a positive-testing patient do not need to take any specific action.
What about people travelling from abroad?
Those who have travelled to Cambodia, mainland China, Hong Kong, Iran, northern Italy, Japan, Laos, Macau, Malaysia, Myanmar (Burma), Singapore, South Korea, Taiwan, Thailand or Vietnam in the last 14 days, or believe they may have Covid-19 or been in contact with someone who does, are advised to call the NHS 111 helpline.
PHE follows the exact same contact tracing process in suspected cases entering the UK, applying its information-gathering from the moment of arrival in the country, and uses translators to make sure everything is fully understood.
How effective is the system?
PHE’s protection team follows the same rigorous process when dealing with any infectious disease and its methods are tried and tested.
They have been used in the past to contain outbreaks of measles, one of the most contagious diseases.
Some of the earliest cases of coronavirus in the UK were uncovered as a direct result of contact tracing: for instance, the four identified in a single day on February 11.
“Our priority has been to speak to those who have close and sustained contact with confirmed cases, so we can advise them on what they can do to limit the spread of the virus,” said a PHE spokesperson.
What happens next?
When confirmed cases are healthcare workers – for example, the two diagnoses that led to the closure of two linked GP surgeries in Brighton – teams work on identifying all of the patients they may have had contact with.
“As soon as they were identified, we advised them to self-isolate in order to keep patient contact to a minimum,” the PHE spokesperson added.
They will also identify all patients and other healthcare workers who may have come into close contact. Only a handful of further cases have been identified since, suggesting the spread from these cases was successfully contained.
“We would like thank all those who have followed public health advice and have taken the necessary steps to reduce the risk to the general public,” the spokesperson added.