Do COVID-19 vaccines work?

Israel is currently leading the way with COVID-19 vaccination; 62.5% of people have had at least one dose of vaccine. The UK isn’t far behind, with 1 in 2 people having had a COVID-19 jab. Given the UK is only vaccinating adults, it’s actually vaccinated 2 in 3 people. That’s a substantial proportion of the population, with all vulnerable adults having been offered a jab. 💉

Thanks to a lockdown and vaccinations, positive coronavirus tests and related deaths have been falling since January in Israel. The UK has a population of 68 million people, much larger than Israel’s 9 million, so how are things working out here?

Has the UK beaten coronavirus?

The UK went into a lockdown at the start of January. Schools re-opened in March, with restrictions gradually easing since then. Around the same time, testing capacity was dramatically increased, improving detection of asymptomatic cases. On one day in March nearly 2 million coronavirus tests were conducted! Despite this, the number of positive tests still continues to fall, as does the number of people in hospital with coronavirus and COVID-19 related deaths.

So how does this relate the the vaccine roll-out, what were the key milestones?

The UK split its 53 million adult population into three categories:

  1. Priority cohorts 1 to 4 – 15 million people
    • This group included over 70s, the Clinically Extremely Vulnerable (those shielding), as well care home residents, and those who work in care homes, health care and social care
  2. Priority cohorts 5 to 9 – 17 million people
    • This group included over 50s, as well as anyone deemed to be at risk due to their job or social circumstances
  3. General population – 21 million people
    • Everyone else

Cohorts 1 to 4 account for around 88% of all COVID-19 deaths, while groups 1 to 9 account for 99% of all deaths. So once 32 million people have been offered a jab, there will be a significant reduction, near elimination, in the likelihood of deaths from COVID-19.

That’s huge!

So where are we at? Currently, around 35 million people have had a first jab, 16 million of which have also had a second. That’s a mix of the AstraZeneca, Pfizer, and Moderna vaccines.

That means all the most vulnerable groups (accounting for 88% of deaths) are fully vaccinated – bar those who’ve refused a vaccine.

Here are some charts showing the UK’s progress. The delivery forecast is based on the 90-day average of vaccinations administered.

The data is all going in the right direction, and I feel quite confident in saying: yes, COVID-19 vaccines do work and the UK is beating coronavirus. Vaccinations are effective at reducing hospitalisation, death, but also at reducing virus transmission.

Points to consider

The more people who catch COVID-19 (globally) the greater the risk of new variants or strains, these could potentially be more harmful, transmissible and vaccine-resistant, but they could also be more benign. Until we’ve stamped out COVID-19 globally, there will be a risk that even a highly vaccinated country could go backwards.

There are also ethical questions around vaccine supply. The UK provided funding and support to multiple vaccine programmes very early on, helping it to secure supplies of several vaccines. Now it’s vaccinated it’s most vulnerable, is there a case for it to gift or sell on doses to other countries with fewer supplies and higher need? Countries like India, which is struggling with the pandemic at the moment. A vaccine given to a not-at-risk adult may stop 1 death in 100,000 in the UK, whereas if given to someone at risk in India right now, it could save 1 in 1,000. It could also free up health care capacity, to support others who haven’t been vaccinated yet.

Wherever you are in the world, there is cause for optimism.

Vaccines work and we are turning the tide on COVID-19! 😊

UK Vaccination Progress Update

The UK has set out its steps to reduce coronavirus restrictions. It’s hoped the fantastic progress of the vaccination programme will mean this is the last COVID-19 lockdown in the UK.

We’ve been told that decisions will be informed by the data, so let’s dig into the stats!

Cases – and the rate of infection

Cases have been dropping for the last seven weeks, from a high of 414k confirmed cases in Week 44 – 4th of Jan to 10th of Jan. The ONS estimated 1 in 50 people had the virus in England in the last week of 2020. That’s now dropped to 1 in 145 people.

The rate of infection (the “R” rate) has been below 1 for seven weeks now – by my estimates, which are based on the reported positive test results.

An “R” of 0.9 means every 100 people with the virus, infect a further 90. An “R” of 1.1 means those 100 people instead infect 110 people.

Cases are going in the right direction, although I’d argue it’s not cases that matter anymore.

UK COVID-19 Cases, Hospitalisations, Deaths and Vaccinations

Hospital Patients

The reason we’ve all been asked to “Stay at home” is to “Protect the NHS” and “Save lives”. The more people who get ill with coronavirus, the more pressure that puts on the National Health Service.

It’s okay to have COVID-19 cases if nobody goes to hospital. Thanks to the vaccine roll-out, fewer people are, and here’s a great visual tweet explaining why.

Vaccination almost completely eliminates the chance of getting severe or moderate symptoms!

There are still significant numbers of people in hospital, but it’s now less than half the peak and dropping further.


The vaccine will reduce hospital admissions, but it’ll also reduce deaths – even more significantly so.

Even a single dose of the Oxford-AstraZeneca and Pfizer-BioNTech vaccines is proving to have a significant impact on immunity to COVID-19. This is great news and will be contributing to the rapid fall in deaths in the UK.

In just five weeks, the UK has gone from ~8.7k coronavirus deaths a week to ~2.3k. To put that in perspective, around 3.2k people sadly die from cancer each week.


Here’s why the UK has been able to set-out it’s roadmap out of lockdown: the vaccine roll-out.

The UK is vaccinating the entire adult population (53 million people) meaning it needs to administer 106 million vaccinations.

So far over 1 in 3 people have had their first dose, and the programme is already over 20% complete.

UK COVID-19 Vaccine Progress

If the UK continues to roll-out vaccinations at the current rate, it’s set to meet, if not exceed its targets to re-open the country.

All the data I’ve shared in this post comes from the UK Gov Coronovirus Dashboard. Predictions are based on my interpretation of this data and vaccine supply data.

How does the UK Approved COVID-19 vaccine work?

Synthetic Biology Technology has brought us to the point today that the UK has accepted one of the COVID-19 vaccines for distribution, with the promise that distribution will begin soon. This result has taken just 10 months, how have the pharmaceutical researchers managed to do this? Through advances in technology.

In reality, there are different types of COVID-19 vaccine currently in trials:

1: Live attenuated vaccines

Some well-known vaccines for other infectious diseases are based on weakened versions of a virus.  These are known as live attenuated vaccines.
The viruses are weakened to reduce virulence by culturing cells in a laboratory, and then processed into a vaccine. After people come into contact with these attenuated viruses through vaccination, the virus will not be able to replicate easily in humans. As a result, our immune system has enough time to learn how to fight against this weaker form of the virus. This approach enables us to become immune without getting sick.

2: Inactivated vaccines

Inactivated vaccines contain viruses or bacteria that have been killed, which are either whole or in pieces. When our immune system detects these dead viruses or bacteria or their fragments, it can learn to recognise the fragments. After this, we are protected. If we are infected by the live version of the virus or bacteria in the future, our immune system will recognise the virus or bacteria and respond more quickly to protect us from infection – so we will not become ill.

3: Subunit vaccines

If the vaccine only contains particular pieces of a virus or bacteria, it is known as a subunit vaccine. When that subunit can be recognised by the immune system, it is referred to as an antigen.
Extensive research is being carried out on subunit vaccines for protection against COVID-19. An important subunit of SARS-CoV-2 is the spike protein or S protein, which is attached to the exterior of the virus. The virus uses the S protein to make contact with another protein which is located on the exterior of the cells in our lung vesicles. If the virus attaches itself to a human cell via the S protein, the virus can penetrate the exterior and enter the cell. Then the cell is infected.  Because the S protein plays such an essential role in the infection process, it is targeted by many vaccine developers. If we are infected by the live version of the virus in the future, our immune system will immediately recognise the virus and we will not become ill.

4: mDNA and mRNA vaccines (m stands for messenger)

DNA and RNA vaccines add a new piece of genetic material – deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) – to specific immune cells in our body. The targeted cells are often a particular type, which absorb and break down a virus or bacteria. The immune cells that have broken down a virus or bacteria then show a piece of the virus or bacteria (a subunit known as an antigen) to other immune cells so they learn to recognize the antigen. That is why these immune cells are also referred to as antigen-presenting cells. The cells that learn to recognize the antigen are called lymphocytes. DNA and RNA vaccines allow the antigen-presenting cells to detect a piece of the pathogen without the cell first having to absorb and break down the live version of the virus or bacteria. If we are then infected by the live version of the virus or bacteria in the future, the lymphocytes will recognize the antigen for the pathogen, neutralize the virus or bacteria, and we will not become ill.

There are also DNA and RNA vaccines that use ‘normal’ body cells instead of immune cells. These cells also present the antigen to our immune system, which ensures that we will not become ill if we do get infected. 
These DNA and RNA techniques are new, and a DNA or RNA vaccine has not yet been approved for any human disease. A number of DNA vaccines have already been used successfully for animals.

5: Vector vaccines

Researchers can modify existing viruses to act as vaccines. Once that happens, they are no longer viruses, but vectors. The viruses have been adapted in such a way that they do not display exactly the same behaviour as unmodified viruses. The difference compared to the real viruses is that vector viruses:

  • can no longer make someone ill;
  • (often) cannot replicate themselves, and;
  • not only contain their own RNA or DNA, but also have a piece of RNA or DNA from another virus within them. All pieces of RNA or DNA can work as an antigen, so the cells in our immune system will react to the vector virus as well as to part of the vaccine virus. This is how immunity is developed.

A category of viruses that are often adapted into a vector are the adenoviruses. Adenoviruses are a group of viruses to which people are often exposed, but which cause no or only mild illness. Because adenoviruses are so common, our immune system is very good at dealing with an adenovirus infection.

This article in Nature goes into further detail.

The vaccine approved today in the UK from Pfizer/BioNTech is an mRNA vaccine. This is cutting-edge technology, and the first time such a vaccine has been approved!

To produce an mRNA vaccine, scientists produce a synthetic version of the mRNA that a virus uses to build its infectious proteins. This mRNA is delivered into the human body, whose cells read it as instructions to build that viral protein, and therefore create some of the virus’s molecules themselves. These proteins are solitary, so they do not assemble to form a virus. The immune system then detects these viral proteins and starts to produce a defensive response to them.

Synthetic Biology!