Medical Centre

Lateral flow tests are now being used by many members of the public. In this article, I answer some of the common questions that people ask about these tests, which I was asked to comment on for an article for the Guardian Newspaper . 1. How do lateral flow tests work and how reliable are they? Lateral flow test (LFTs) work by detecting the proteins on the surface of the SARS-CoV-2 virus that is the cause of Covid-19. They can be carried out at home and don’t require a laboratory to process the test, unlike PCR tests. They also give a result very quickly, typically within 30 minutes. They are less accurate than PCR tests, which is why these are recommended for people with symptoms. Studies show widely varying estimates of the accuracy of LFTs, typically detecting between 40%-90% of people who have Covid-19 in different studies. We can’t just take an average of these studies to determine the accuracy of the tests as this will depend on a range of factors – such as the type of people...

In an article for VICE UK , I answer questions from Darcey Edkins about staying safe this Christmas in the midst of a wave of Covid-19 infections driven by the Omicron SARS-CoV-2 variant. We cover topics such as the Three C Approach to personal safety, why you should wear a well-fitting FFP2 mask, and testing for Covid-19.  1. Given the scientific data out there, is it safe to travel home for Christmas right now? There is currently a high level of Covid-19 in the UK so you need to take appropriate precautions when travelling such as adopting the “ Three C Approach ” to reduce the risk of infection to you. This means: Avoid closed spaces; Avoid crowded spaces; Avoid getting too close to other people when outside your household. When you travel home, you should use a good quality FFP2 face mask to protect yourself better if you are on public transport or enter places such as bus, train and service stations. You can test yourself before you travel with a lateral flow test. If you h...

One question I have been asked is why the London-region has been the area of the UK most affected by the Omicron variant of SARS-CoV-2? Over 80% of Covid-19 cases in London are thought to be due to Omicron compared to a national average in England (as of 19 November) of 67%.  There are several factors that have driven the rapid increase in Omicron cases in London. London is the UK’s main international travel hub with the UK’s busiest airports located nearby. Hence, travellers from overseas who are infected with a new variant of SARS-CoV-2 are more likely to arrive in the London region than in other parts of the UK. London also has a very large number of international visitors – for activities such as work, study, tourism, leisure, and sports events.  London is the also UK’s largest city and is very densely populated, with many overcrowded households, often with people from three generations living together (multi-generation households), which makes infections more likely to sp...

Several patients have asked me if  lateral flow devices (LFDs) will detect Omicron infections. These are the rapid tests that people can use to check for Covid-19 infection while they are asymptotic. NHS staff are required to use these tests regularly if they are in patient-facing roles. Short Answer: Yes. The UK HSA has confirmed this in an initial laboratory evaluation of the LFDs currently used in the UK. The data from the initial samples in the HSA study show a similar sensitivity for the detection of Covid-19 from Omicron to that seen for previous strains of SARS-CoV-2 including Delta, which has been the predominant strain in the UK from May to December 2021.  All LFDs approved for use within the UK specifically detect the nucleocapsid protein of SARS-CoV-2 using a combination of 2 or more different antibodies, each targeting a distinct epitope. Full details of the study are available on pages 14-16 of the HAS study. Finally, remember that LFDs are not 100% sensitive and ...

On Friday 17 December, a record number of Covid-19 cases (93,045) was reported in the UK.  Unfortunately, the recently identified Omicron variant has proven to be considerably more infectious than previous variants. Vaccines are also less effective against Omicron, with two doses of the vaccine providing only limited protection from symptomatic Covid-19 infection. A booster (third) dose increases protection but not to the level seen against other variants.  Although the clinical severity of Omicron-linked cases is still to be fully determined, the sheer volume of cases will lead to greater pressures on all sectors of England’s NHS. This comes at a time when the NHS in England is already struggling to cope with existing demands, whilst also trying to manage the enormous backlog that has built up since the start of the pandemic in early 2020.  With the NHS now tasked with substantially increasing the number of Covid-19 vaccines available, we are entering a very challenging ...

With the number of covid-19 cases from the Omicron SARS-CoV-2 variant rising exponentially in the UK, Boris Johnson, the prime minister addressed the nation on 12 December 2021, announcing a target to deliver a booster covid-19 vaccine to all eligible adults in England by the end of December. The devolved governments in Wales, Scotland, and Northern Ireland are expected to set similar targets. This extremely ambitious target will involve delivering over one million covid-19 vaccines per day in England over the next couple of weeks. So far, 81.3% of adults have received two vaccine doses in England, but despite this the covid-19 alert system in England moved from 3 to 4 as a result of the large increase in daily case rates and the concerns that the latest variant is overwhelming the NHS. 1 2   In response, the Joint Committee on Vaccination and Immunisation has recommended reducing the time between second doses and boosters from six months to three months, rendering 14 million more ...

The UK is facing a surge in Covid-19 infections from the Omicron variant of SARS-CoV-2 coronavirus with a record number of Covid-19 cases (78,610) reported in the UK today. Cases of Covid-19 due to Omicron will soon account for most infections in the UK. Omicron has proved to be highly infectious - more so than other variants of SARS-CoV-2 - and is also able to evade vaccines better than other variants. To protect yourself, and reduce the risk of infection to you and others remember the three C approach to personal safety: - Avoid closed spaces - Avoid crowded spaces - Avoid getting too close to other people when outside your household These are simple and effective messages that need to be disseminated and adopted widely. Remember also to get vaccinated - including with a booster as well as your first two doses - and to wear a good quality FFP2 mask when in indoor spaces outside your home. Three doses of vaccines provide much better protection against symptomatic Covid-19 infection th...

When am I allowed to have my booster? You can have your booster Covid-19 vaccine once you are three months past your second vaccine dose. The gap was previously six months but has now been reduced. Who is eligible for a booster? Anyone aged 18 and over is now eligible for a booster. People aged 16-17 with underlying health conditions that put them at higher risk of severe Covid-19 are also eligible for a booster. The NHS will aim to vaccinate people in order of clinical priority. Can I have a booster if I’ve never been vaccinated? You can’t have a booster until you are three months past your second Covid-19 vaccination. If you have not been vaccinated, you will need to have your first two vaccine doses eight week apart and then get your booster three months after your second dose People who are not vaccinated are at much greater risk of a serious Covid-19 illness, hospitalisation and death. So please do come forwards for vaccination if you are currently unvaccinated. Does a...

 The number of Covid-19 cases in the UK has increased in recent weeks to an average of around 50,000 per day. The number of cases caused by the Omicron variant, although currently small, is doubling about every three days. If this increase continues, Omicron will replace Delta as the most common variant of the Coronavirus in the UK within a few weeks. This is concerning because it looks like our current vaccines may be less effective against the Omicron variant than against the Delta variant. The good news though is that three doses of a vaccine (the first two doses followed by a booster dose) should continue to provide good protection from serious illness, even if current Covid-19 vaccines are a little less effective against Omicron. To help counter the threat from Omicron and limit the pressures on the NHS, the government is introducing new measures in England to reduce the risk of infection. As well as following the new rules, you should also ensure you are fully vaccinated – in...