In the UK those who think they have COVID-19, including confirmed cases, isolate at home for 7 days after onset of symptoms. Matt Hancock, the health secretary, was confirmed to have COVID-19 a week ago. He has just come out of isolation after 7 days. See: Matt Hancock leaves week-long isolation period under UK's 'outlier' rules

This is radically different from the WHO isolation period. According to the WHO he is still infectious and could contribute to the spread of the disease. He should only leave isolation this early if he has two negative PCR tests 24 hours apart.

The WHO advice is actually to self isolate for two weeks after symptoms disappear:

People infected with COVID-19 can still infect others after they stop feeling sick, so these measures should continue for at least two weeks after symptoms disappear.

Visitors should not be allowed until the end of this period.

WHO Director-General's opening remarks at the media briefing on COVID-19 - 16 March 2020

Before I go any further, just a reminder, you can protect yourself from this disease. It seems to be transmitted only via larger droplets that come out of your mouth when you cough, sneeze or talk and these fall out of the air in seconds. It is not airborne on smaller droplets in the way flu is [except for certain medical procedures].

This is another article I'm writing to support people we help in the Facebook Doomsday Debunked group, that find us because they get scared, sometimes to the point of feeling suicidal about it, by such stories.

Please share this to help others who can be helped by it, and especially with scientists, politicians and decision makers in the UK

Video about this:

(click to watch on Youtube)


Text on image:

Self-isolation (UK advice)

If you have been symptomatic, then you may end your self-isolation after 7 days. The 7-day period starts from the day when you first became ill

Household isolation

If living with others, then all household members who remain well may end household-isolation after 14 days. The 14-day period starts from the day illness began in the first person to become ill. Fourteen days is the incubation period for coronavirus; people who remain well after 14 days are unlikely to be infectious.

After 7 days, if the first person to become ill feels better and no longer has a high temperature, they can return to their normal routine. If any other family members become unwell during the 14-day household-isolation period, they should follow the same advice - that is, after 7 days of their symptoms starting, if they feel better and no longer have a high temperature, they can also return to their normal routine.

[see Stay at home: guidance for households with possible coronavirus (COVID-19) infection]

Overlay: WHO’s isolation period is through to death for those that die, through to 14 days after recovery or two negative PCR tests 24 hours apart for those who recover.

The WHO's advice is to isolate patients until they have negative PCR positive tests 24 hours apart or for 14 days after end of symptoms. The Director General put it like this:

Caring for infected people at home may put others in the same household at risk, so it’s critical that care-givers follow WHO’s guidance on how to provide care as safely as possible.

For example, both the patient and their care-giver should wear a medical mask when they are together in the same room.

The patient should sleep in a separate bedroom to others and use a different bathroom.

Assign one person to care for the patient, ideally someone who is in good health and has no underlying conditions.

The care-giver should wash their hands after any contact with the patient or their immediate environment.

People infected with COVID-19 can still infect others after they stop feeling sick, so these measures should continue for at least two weeks after symptoms disappear.

Visitors should not be allowed until the end of this period.

WHO Director-General's opening remarks at the media briefing on COVID-19 - 16 March 2020

Detailed advice from the WHO:

For mild laboratory confirmed patients who are cared for at home, to be released from home isolation, cases must test negative using PCR testing twice from samples collected at least 24 hours apart. Where testing is not possible, WHO recommends that confirmed patients remain isolated for an additional two weeks after symptoms resolve

Home care for patients with COVID-19 presenting with mild symptoms and management of their contacts

The patients shed virus for a long time. Through to death for those that die.

Duration of viral shedding ranged between 8 and 37 days. The median duration of viral shedding was 20·0 days (IQR 17·0–24·0) in survivors, but continued until death in fatal cases. Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study

It is true that viral shedding does not mean that it's live virus. For SARS then the live virus could be cultivated for three weeks, but they continued to shed virus for a month.

For SARS coronavirus, viral RNA is detectable in the respiratory secretions and stools of some patients after onset of illness for more than 1 month, but live virus could not be detected by culture after week 3

Understanding COVID-19: what does viral RNA load really mean?

However, the patients do shed virus all the way through to death and half the survivors continue to shed the virus for 20 days or more.

An infector can also infect someone else many days BEFORE symptom onset - which is why it is so important to trace contacts and isolate those.

This is an example paper examining serial pairs amongst 468 confirmed cases in China as of 8th February 2019, paper published on 19th March.

The paper explains that by a serial pair they mean the time interval between the infector reporting symptoms and the infectee reporting symptoms.

The serial interval of COVID-19 is defined as the time duration between a primary case-patient (infector) having symptom onset and a secondary case-patient (infectee) having symptom onset

12.6% have negative intervals meaning the infectee developed symptoms before the infector. The largest negative interval is -10 days i.e. the person they infected developed symptoms 10 days before the infector.

That’s figure 1 from this paper Serial Interval of COVID-19 among Publicly Reported Confirmed Cases.

In the other direction, the 20 days difference between onset of symptoms in infector and infectee does not tell us much. You need the time between onset of symptoms in the infector and the contact that infected the infectee. There must be studies of this too - do say if you know in comments.



COVID-19 both is and isn't more contagious than flu. It is not airborne, and in that sense is not more contagious. But it does transmit through prolonged and close contact and it is infectious for much longer than flu. All the way through to death, or to two weeks after recovery and all symptoms disappearing.

It is also infectious for several days before you get the symptoms, and that also makes it more infectious than flu.

Flu is only infectious for about 12 hours before symptoms and then for about 7 days after they start, most of that in the first part of that period.

About a third of those who get flu never show any symptoms, but can still infect others. Those able to infect others with COVID-19 nearly always develop symptoms later, and so can be found and their contacts traced.

So COVID-19 is both more and less infectious than influenza. It is just not the same disease and transmits in a different way. A strategy that works for flu is not likely to work so well for COVID-19 and vice versa.

There are many other differences between the simulated flu used by these researchers and the real COVID-19 data.

From what I can tell the UK epidemiologists base their model on data for flu, not for COVID-19. All they take from the data from COVID-19 is an estimate of the incubation period.

I summarize the main differences in this graphic:


Meanwhile you can do a lot to protect yourself with simple effective measures. If you are in the UK and aren’t doing these yet, I recommend starting on them right away. Our government hasn't explained this clearly enough - at least most that I talk to via private messaging in the UK who contact me scared of COVID-19 do not fully understand the importance of this when they first contact me. They think that they are bound to get COVID-19 eventually and all they can do with physical distancing is to help delay the infection to a time when the health service is under less pressure.

This is NOT TRUE. This virus is transmitted via large droplets that people expel when they cough, sneeze or talk. They fall to the ground in seconds. You can only be infected if these droplets land in your eyes, nose or mouth, or if you touch a surface they fell on and then touch your eyes nose or mouth. It is not a contact virus and can only get into your body that way.

See WHO tweet here

This is part of the infodemic including sharing academic articles that are actually about aerosols produced through medical procedures, and other articles that are mistaken and withdrawn.

There were several clear examples of airborne transmission of SARS early on. Now after a million cases of COVID-19 we don't yet have an example of it happening. The WHO continue to monitor the situation and read all the papers on the topic, and see no reason to modify their advice that it is NOT AIRBORNE

For techy details: Modes of transmission of virus causing COVID-19: implications for IPC precaution recommendations

See my The coronavirus COVID-19 is NOT AIRBORNE

Follow the advice on distancing and washing your hands thoroughly before touching your eyes, nose and mouth, and this virus can’t get into your body.

It is a bit like people not bothering to wear seat belts in cars before "Clunk click Every Trip".

Do you do these four things?

  1. Wash hands thoroughly
  2. Stay 1-2 meters from anyone coughing.
  3. Wash your hands before you touch your eyes, nose or mouth [try to get out of the habit of touching your face in the day]
  4. Cough or sneeze into your elbow OR cough or sneeze into a tissue and put it into a bin immediately. [this is to protect others]

Do this as thoroughly as the experts, and you can say:

"I don't have COVID-19 - I am very low risk".

Dr Bruce Aylward said that immediately after he returned from Wuhan. He knew he was safe because he did those things.

He did also wear a mask, because that was Chinese policy - but that was to protect others. It doesn't protect you, for instance droplets can still enter through your eyes if you are too close to someone with the virus. He didn’t speak directly to patients or contacts - but anyone he met there could have had COVID-19 and he protected himself with these measures of careful physical distancing and hygiene.

The WHO stress that these simple measures save lives. They are not hard to do if you make them into a habit. More details here:

We all need to carefully follow the instructions to protect ourselves and your loved ones and tell everyone else about what they need to do to stay safe. These instructions work. You also help others too, every time you do this you are also helping to break the transmission chain to others.


See also my

For the latest WHO press briefings go to

Press briefings

There is still much we can do and great hope. See

See also my


Do please say if you notice anything here that needs correcting or anything I leave out. I am a science blogger doing my best to present the science accurately. I am not an epidemiologist. Most of what I say is based on listening to the WHO. I have listened to all their press briefings on COVID-19 since they started and I often also follow up on their remarks and find the papers they refer to and read those.

And of course do say if you have any thoughts on this too.