The spread of coronavirus through the UK population will be tracked with the help of a new study that the government hopes will help pin down immunity levels and infection rates.
Some 20,000 households in England are being contacted to take part in the first-wave of the research, with initial findings expected in early May.
All participants will provide a nose and throat swab to test for whether or not they currently have the virus.
Adults in some 1,000 of the households will provide a blood sample to find out what proportion of the population has developed antibodies to Covid-19.
The Department of Health and Social Care (DHSC), leading the study with the Office for National Statistics (ONS), said participants will form a representative sample of the UK population by age and geography.
Those selected will provide samples taken from self-administered nose and throat swabs and answer a few short questions during a home visit by a trained healthcare professional.
Swab tests will show whether or not participants currently have the virus.
They will be asked to take further tests every week for the first five weeks, then every month for a year.
In total, the Government says some 25,000 people will take part in the pilot phase with plans to extend it to up to around 300,000 over the next 12 months.
Scientists will also analyse blood samples from adults in around 1,000 households to determine how many people have developed antibodies to the virus.
Antibody testing is considered crucial in providing an exit pathway from the current lockdown, and also providing data to those developing a vaccine.
England's chief medical officer Professor Chris Whitty said at Wednesday's daily Downing Street briefing that there is currently not a test available that Public Health England (PHE) has enough confidence in.
Scientists at Oxford University are in the process of validating an antibody test, also known as an Elisa test, which will be used in this study.
They are on track to have a "fully validated and an accreditation compliant test" in place by May 4 according to Professor Derrick Crook, who is among those co-ordinating the programme of work at Oxford.
This laboratory test will be used in the study by DHSC and ONS, but Prof Crook said there is capacity to process well over 20,000 tests a day should there be such a demand for testing.
Participants in the antibody test will be asked to give further samples monthly for the next 12 months.
The Government says nose and throat swabs will be taken from all participating households, whether their members are reporting symptoms or not.
Blood for antibody tests will not be taken in any households where someone has symptoms of Covid-19 or is currently self-isolating or shielding.
Although swab test results will be given to participants via their GP, a letter seen by the PA news agency says that those participating in the antibody test will not receive their results.
The de-identified blood samples will be sent to Oxford University to be tested for antibodies, while infection testing swabs are to be sent to UK Biocentre.
Health Secretary Matt Hancock said: "This survey will help to track the current extent of transmission and infection in the UK, while also answering crucial questions about immunity as we continue to build up our understanding of this new virus.
"Together, these results will help us better understand the spread of the virus to date, predict the future trajectory and inform future action we take, including crucially the development of ground-breaking new tests and treatments."
