When can I stop shielding? And other questions

So far the vaccines seem to provide equally good protection against the UK variant - which emerged in the autumn and has now become the main strain of the virus in circulation.

There are signs the vaccine could be slightly less effective against another mutation found in the South Africa variant, but nevertheless the jab will still give very good protection.

And while the virus will keep mutating, vaccine developers are poised to update their jabs at relatively short notice.

Cases of the South Africa variant are in their tens in the UK at the moment, so it’s hoped travel bans will restrict further imports of cases containing this and any other genetic changes, that could make suppressing the virus more difficult.

The UK variant shares some similarities with the South African one, but doesn’t generally have one of its more worrying mutations. The genetic change dubbed “E484K” shows signs of being able to hide from the body’s immune response and may cause vaccines to be less effective.

However, the scientists who study the genetic makeup of coronavirus have found a small handful of test samples which, while they look like the UK variant, also have the addition of this alarming mutation.

A tiny number of samples (about 10) have been detected in Bristol which look like the Kent variant, but appear to have an additional mutation which it’s feared could make the vaccine slightly less effective.

Everyone in the relevant area is being invited for tests whether or not they have symptoms, and the government has said it is “critical” they stay at home apart from when it is “absolutely essential” – although no formal additional restrictions have been put in place.

Mutations happen when viruses reproduce inside the body, and there’s a limited number of ways in which they can change - so we do see the same changes happening independently of each other in different countries.

The UK variant and the South African variant for example are made up of distinct constellations of mutations – but they contain some of the same genetic changes within them.

It’s not clear yet how long immunity might last after vaccination.

It is possible that people will need to be vaccinated annually or every few years to have protection.

Yes. Allergy to penicillin is not listed as a clinical reason to avoid having either the Pfizer-BioNTech or the AstraZeneca-Oxford Covid-19 vaccine.

However, when you are invited for your Covid vaccine, you should discuss your allergies with healthcare staff to make sure there is no other reason to avoid it.

Although it’s been done quickly, this vaccine trial hasn’t skipped any of the usual steps.

The only difference is that some of the stages overlapped so, for example, phase three of the trial – when tens of thousands of people are given the vaccine – started while phase two, involving a few hundred people, was still going on.

Side effects usually show up quite quickly after vaccination and longer-term effects are extremely rare – much, much rarer than long-term side effects of the virus.

Usually vaccine trials are slowed down by long periods of waiting around, applying for permission, funding and resources.

It’s those elements that were sped up, because of the huge global interest in doing so.

People will be vaccinated whether or not they’ve had Covid.

We don’t yet know how long natural immunity lasts, and vaccination can offer better protection than immunity from the disease itself.

No, people in the UK are not being told they must have the vaccine.

However, those in the most at-risk groups (over-70s and care home residents), and people who work in care homes and for the NHS will be expected to have it - to protect themselves and the people they care for.

Making a vaccine mandatory is not usually recommended because it can lower confidence in the jab.

Scientists don’t know the exact answer to that at the moment.

The volunteers in the vaccine trials who were given the jab will be followed up for many months to come to check how long they are protected for.

Natural immunity to the virus, once someone has been infected, appears to last at least six months so it’s likely a vaccine will offer this length of protection and hopefully a lot more.

The vaccine significantly reduces the risk of getting seriously ill with coronavirus. But it is unclear whether it stops people from catching the virus or passing it on to others.

So it is really important that people continue with social distancing, wearing face coverings and washing their hands, even if they have been immunised.

If your immune system is suppressed and not working as well as it might, some "live" vaccines are not recommended. This is because the weakened virus they are made from could cause problems.

The Oxford vaccine is not a "live" vaccine. Scientists are testing which patients could benefit from it and whether this might include people with certain health conditions, or who are taking particular medication or undergoing treatment for something else, such as cancer or HIV.

There are lots of different Covid vaccines in development and some may be more suitable for different groups than others.

Neither the Pfizer jab nor the Covid vaccines that could soon be approved for use - Moderna or Oxford/Astrazeneca – are made using eggs so there should be no issue for people with egg allergies.

No vaccine is 100% effective for everyone. And 70% is still very good, particularly for a disease as serious as Covid-19.

US regulators had said they would accept 50% protection as worth pursuing for Covid. Flu jabs are between 40% and 60% effective.

Both vaccines need to be stored at below freezing temperatures when they are transported from the factory out to clinics.

The Pfizer jab needs to be kept at around -70C, which is somewhat challenging, while the Moderna one can be kept in a normal freezer temperature of -20C.

Both can be thawed and kept in a fridge once they arrive at the clinic, but the Pfizer one then has a short shelf life of five days compared to four weeks for the Moderna vaccine.

The NHS has been planning how best to roll out the vaccine. It will be a large-scale immunisation programme, requiring lots of trained staff to administer the jabs.

Pharmacists, nurses, doctors and other healthcare professionals will be able to vaccinate people in a range of settings – including care homes, hospitals and GP clinics as well as pop-up centres, such as sports stadiums and conference buildings.

It could mean some delays to some non-Covid NHS services, but urgent and essential care will be prioritised. The aim is to keep usual services running whenever possible. You could contact your GP to discuss any concerns you have.

Scientists have said that the “incubation period” - the time between catching the virus and starting to show symptoms - is five days on average. However, some people can have symptoms earlier or much later than this.

The World Health Organization advises that the incubation period can last up to 14 days. But some researchers say it may be up to 24 days.

Knowing and understanding the incubation period is very important. It allows doctors and health authorities to introduce more effective ways to control the spread of the virus.

Both viruses are highly contagious.

On average, it's thought people with the coronavirus infect two to three other people, while those with flu pass it on to about one other person.

There are simple steps you can take to stop the spread of flu and coronavirus:

• Wash your hands often with soap and water

If you have returned from holiday abroad and have to self-isolate in quarantine, you will not automatically qualify for Statutory Sick Pay (SSP), so it's possible you might have to make arrangements with your employer if you cannot work from home.

• Catch coughs and sneezes in a tissue and then put it in the bin

Asthma UK's advice is to keep taking your daily preventer inhaler (usually brown) as prescribed. This will help cut the risk of an asthma attack being triggered by any respiratory virus, including coronavirus.

Carry your blue reliever inhaler with you every day, in case you feel your asthma symptoms flaring up. If your asthma is getting worse and there is a risk you might have coronavirus, contact the online NHS 111 coronavirus service.

Coronavirus can be more severe in older people and those with pre-existing conditions such as heart and lung illnesses, or diabetes.

There is no evidence that disabled people who are otherwise healthy - and who don't, for instance, have respiratory problems - are at greater risk from coronavirus.

Covid-19 can, in a small number of cases, lead to pneumonia, most notably in people with pre-existing lung conditions.

But as this is a new virus, no-one will have any immunity to it, whether they have previously had pneumonia, or any other form of coronavirus such as Sars.

Wearing masks presents major challenges for some deaf people who rely on lip-reading to communicate, but who also need to stay safe from catching the virus, especially if in a hospital setting.

The charity Action on Hearing Loss says there are some clinically approved see-through covered face masks that help enable lip-reading. However, they do not provide enough protection against aerosols spread by coronavirus, and wouldn’t be right for health and social care workers to use during this pandemic.

Many of the experimental coronavirus jabs currently being tested contain the genetic instructions for the surface spike protein that coronavirus uses to attach to and infect human cells. Reassuringly, scientists have not seen any substantial mutations to this part of the virus yet that would render these vaccines useless.

If you’re living with someone who’s self-isolating, you should keep all contact to a minimum and, if possible, not be in the same room together.

The person self-isolating should stay in a well-ventilated room with a window that can be opened, and keep away from other people in the house.

If you live with someone who has symptoms, you'll also need to self-isolate for 14 days from the day their symptoms started.

If you get symptoms, self-isolate for 14 days from when your symptoms start, even if it means you're self-isolating for longer than 10 days. If you do not get symptoms, you can stop self-isolating after 10 days.

If you or your housemates develop symptoms after 00:01 GMT on Monday 14 December, you will only have to self-isolate for 10 days.

If you live with your partner, they count as being part of your household. If neither of you is showing coronavirus symptoms and you are already in close contact, having sex won't increase the likelihood of you catching the virus from one another. If one person does have symptoms, they should be self-isolating in a separate room.

Using contraception such as condoms won't alter your risk of catching the virus, as having sex will bring you into close physical contact anyway.

"If you are going to touch each other's genitals it's likely that you will potentially be kissing at the same time - and we know the virus is passed through saliva," Dr Alex George told the BBC's Newsbeat.

"Essentially, any possibility of transfer of coronavirus - from your mouth to your hands, to genitals, to someone else's nose or mouth - increases the risk of passing on coronavirus."

On balance, this is almost certainly unnecessary.

While hand washing is very important for personal hygiene, none of the advice from the world’s leading health bodies – the World Health Organization for example, the CDC in the US or the NHS in the UK – places any importance on hair washing one way or another.

It’s theoretically possible that you could catch the virus if someone sneezed on your hair and those droplets found their way to your eyes, nose or mouth (for instance if your hair fell over your face).

However, research suggests that while virus droplets can survive for a couple of hours on some non-porous surfaces such as steel, there are few – if any – cases of Covid which can be traced back to being transmitted in this way.

The Department for Transport (DfT) has not made it compulsory for taxi drivers to wear face coverings in England because they say they do not want to interfere with the rules and regulations of different transport operators.

However, DfT still advises that drivers wear face coverings when they are unable to socially distance.

In any case, many major operators – Uber, for example – insist that face coverings are worn by both passengers and drivers.

Transport for London has also asked all taxi and private hire companies to ensure drivers wear face coverings.

Taxi drivers in Wales are advised but not compelled to wear face coverings, but it is mandatory in Scotland and Northern Ireland.

Pregnant women are being advised by the UK government to stay at home and keep contact with others to a minimum. However, they should attend antenatal clinics as normal.

There is no evidence to suggest that pregnant women are more likely to get coronavirus. But, for a small number of women, being pregnant may change the way their body deals with a severe viral infection.

The government’s chief medical adviser says this is a precautionary measure until scientists find out more about the virus and that "infections and pregnancy are not a good combination in general”.

Mothers pass on protection from infection to their babies through their breast milk.

If your body is producing antibodies to fight the infection, these would be passed on through breastfeeding.

Breastfeeding mums should follow the same advice as anyone else over reducing risk - cover your mouth when you sneeze and cough, throw away used tissues straight away and wash hands frequently, while trying to avoid touching your eyes, nose or mouth with unwashed hands.

Self-employed people who have symptoms or have been told to self-isolate may apply for two benefits - universal credit or employment and support allowance.

Normally, you would be eligible after four days of being ill. However, the government has responded to the spread of coronavirus by saying that companies will temporarily pay SSP from the first day off.

But charities are worried that there is still a five-week delay before universal credit is paid.

Unless your flatmates were travelling with you, they do not need to self-isolate or quarantine with you.

However, you must avoid contact with them and minimise the time you spend in shared spaces like kitchens, bathrooms and sitting areas.

You should stay in a well-ventilated room with a window to the outside that can be opened, separate from your flatmates, and if you can, you should use a separate bathroom from them. If you do need to share these facilities, regular cleaning will be required after each person has used them.

Make sure you use separate towels from the other people in your house, both for bathing and showering, and for washing your hands.

Not necessarily.

If you have returned from holiday abroad and have to self-isolate in quarantine, you will not automatically qualify for Statutory Sick Pay (SSP), so it's possible you might have to take the extra time off as annual leave, or else as unpaid leave.

The Department of Work and Pensions says that anyone planning to travel should do so in the knowledge that they will be required to self-isolate on their return.

It adds that employers and staff should discuss and agree any arrangements in advance, and urges employers to take socially responsible decisions.

Meanwhile, the Foreign & Commonwealth Office is still advising UK nationals against taking all but essential international travel.