About our COVID-19 research

We have been working on a number of different studies to understand the biology of COVID-19 and the body’s response, as well as the effects of the pandemic on physical and mental health.

This has only been possible thanks to the incredible commitment and support of our twins. We are very grateful to our twins, who have been taking part in studies throughout the pandemic.

Find out more about our COVID-19 research with Professor Claire Steves and Professor Tim Spector in this webinar:

COVID-19 Personal Experience Study

The COVID-19 Personal Experience (COPE) is a questionnaire study that aims to understand the physical and mental health implications of the pandemic.

We sent out the first round of this questionnaire during the peak of the epidemic in the UK, and we have asked our twins to complete a second, third, fourth and fifth round at other points throughout the pandemic. TwinsUK members have now received their sixth, and hopefully final, round of this questionnaire. The sixth round captured people who may be experiencing Long COVID, as well as more information on the broader impact of the pandemic on individuals, two years on from the first questionnaire.

COVID-19 Home Visit Serology Study

In 2020, we visited over 500 twins at home to collect samples and test participants for active traces of the virus that causes COVID-19, as well as antibodies.

We re-visited a proportion of participants throughout 2020 and 2021 in order to collect further swabs and samples so that we can see how the body’s response to COVID-19 changes over time.

Nurse drawing blood from woman as her twin watches
One of nurses takes a blood sample from a TwinsUK member during the home visit study

COVID-19 Antibody and Health Study

In August 2020, we combined the second round of the COPE questionnaire with an antibody study. We sent finger-prick blood collection kits to TwinsUK members, to collect a small blood sample at home and return it in the post for antibody testing.

COVID-19 Home Antibody Testing Study

In April 2021, we worked with other population cohorts in the UK to carry out an antibody study. 4,500 of our TwinsUK members received a kit in the post to collect a finger-prick blood sample at home. The majority of our twins tested positive for COVID-19 antibodies, suggesting that most of our twins had received a COVID-19 vaccination at the time of the blood collection, or had had a prior COVID-19 infection. 

Twins repeated this exercise in November and December 2021 in order to help us understand how antibody status changes in the months following infection and/or vaccination. 

Antibody kit box


Longitudinal Health & Wellbeing National Core Study

We are members of several multi-university COVID-19 research projects that report findings to the government.

The Longitudinal Health & Wellbeing National Core Study (LHW NCS) is one of six studies established by Sir Patrick Vallance, UK Chief Scientific Advisor, as part of the UK’s response to the pandemic. The LHW NCS aims to understand the health, social and economic impacts of the COVID-19 pandemic by uniting established population cohorts and national anonymised electronic health records to inform policy. Find out more about the work so far here.

NCS logo


Since the pandemic began, people have been reporting that they have continued to experience symptoms for weeks or even months after infection. This can range from mild symptoms all the way to debilitating symptoms that have a major impact on people’s lives. This condition is now described as ‘Long Covid’ – but there is currently no set definition of what constitutes Long Covid, even as more and more people develop the condition.

TwinsUK is part of a multi-university study called CONVALESCENCE, which aims to understand, define and improve diagnosis of Long Covid. There are many parts to this project, and more information is available here.

As part of this project, we are working with collaborators at University College London (UCL) and other population cohorts to carry out a detailed studied of how COVID-19 affects the body. This study will recruit people with a range of COVID-19 experiences. We will contact you directly if you are eligible to take part in this study.

You can also take part in this study by contributing to a discussion about what Long Covid means to you. This is open to everyone.

UK Longitudinal Linkage Collaboration (UK LLC)

For the first time, data from many UK cohort studies will be brought together into one secure research server, managed by universities. Researchers doing COVID-19 research can apply to use data held in the UK LLC. 

TwinsUK staff have helped to shape the UK LLC. TwinsUK has contributed COVID-19 data from TwinsUK participants, and the UK LLC will also be able to link to TwinsUK participants’ health and environmental records, unless they opted out of this. By taking part in the UK LLC, TwinsUK data is playing an essential role in the fight against COVID-19. 

Find out more about TwinsUK’s involvement on pages 14-15 of the Data Linkage Information Leaflet sent to you in 2021.

UK LLC logo

COVID-19 Symptom Study App

Health science company Zoe has developed a COVID-19 Symptom Tracker app with input from King’s College London and Massachusetts General Hospital. The app tracks in real time how the disease progresses. The aim of the app is to help slow the outbreak, by helping researchers identify:

  • How fast the virus is spreading in your area
  • High-risk areas in the country
  • Who is most at risk, by better understanding symptoms linked to underlying health conditions


The app is available for both TwinsUK members and the general public to use. Participants using the app will record information about their health on a daily basis, including temperature, tiredness and symptoms such as coughing, breathing problems or headaches.

Download the app to your Apple or Android device

The app is available to download from the Apple App Store here.

The app is available to download from Google Play here.

CLICK HERE to see a list of questions asked in the App.

Follow our research updates

Our researchers are working round the clock to analyse all the symptom data that’s coming in.

CLICK HERE to find out about our latest findings.


Find answers to frequently asked questions about the app HERE.