What is a contact survey and how can you help?
None of us like being ill. We want to avoid ourselves, or our loved ones, catching an infectious disease like flu, chickenpox or COVID-19. Many of us have also experienced the impacts an epidemic can have on wider society, like schools having to close or people being unable to see friends and family during lockdown
These diseases can spread when people come into contact with one another, for example chatting together in person, sitting alongside someone on public transport, and physical contact like hugging or shaking hands. The type of contact that matters differs with different diseases, but in general, the more time we spend together, the greater the opportunity for infections to spread.
We know that these contacts are important in understanding how these diseases spread. But what scientists do not yet know is exactly how people mix together and when and where these sorts of contacts happen. This is why they carry out studies called contact surveys.
What is a contact survey?
A contact survey focuses on a group of people, say students at a school, and asks them about who they come into contact with during their day, where and how these contacts happen. People answer these questions based on their own personal experience, recording who they have met over a period of time, e.g. from the past 24 hours or from the past week.
Although there is a lot of detail given in the answers in the survey, the information about who answered the questions and the people they met is kept anonymous. Scientists collate the information from all the surveys completed and build an average picture of how the people in that group, say that school, typically mix together and have contact with each other. This information helps them more accurately predict how a particular infectious disease could spread through that group of people, and crucially, what interventions might effectively reduce that spread.
These predictions help inform decisions that are made when an epidemic occurs, such as whether a class, or school should stay at home and isolate to control the spread of the disease.
How you can help
Researchers at Lancaster University are undertaking a new contact survey in schools. They are interested in learning more about the specific places within a school where people come into contact, such as the classroom, canteen, or playground. They also want to understand how often schoolmates come into contact outside of school, and how often young people meet pupils from other schools. This information will help understand how different interventions could be designed to reduce cases of diseases like flu and COVID-19 in schools while also keeping young people in school.
Inspired by previous studies showing the importance of including young people in research (this is called participatory research - you can see an example here) the team are working with school pupils from the very start. Before they conduct the survey, they are co-designing the questions with pupils and schools to make sure they ask questions that accurately reflect the social lives of young people, in a way that is accessible to all ages.
You can find out further information on the study’s website. If you or your school are interested in participating, you can register your interest here.
How is the contact information used?
What is a mathematical model?
A mathematical model is a description of a process in the world around us that is written in terms of mathematical expressions. You've probably intuitively used mathematical models without even realising it, such as calculating how long it will take you to save £100, if you save £10 a week.
Mathematical models are always simplifications of reality and involve uncertainties, but a good model can provide the most educated guess we're ever going to be able to make about how a process may play out.
You can read more in our easy introduction here, and find out the basics of how diseases are modelled mathematically here.
Scientists, called epidemiologists or disease modellers, use mathematics to understand how infectious diseases spread. They build a mathematical model: a mathematical description of how the infection moves through a population.
The data from the contact survey is used to refine the mathematical model so that the predictions it makes are more accurate, and so they can better understand the impact different interventions may have.
Contact surveys reveal important information about how and where different groups of people mix. For example, it can provide evidence for how children mix within year groups compared to between different year groups.
You can read more about how one of the researchers from this study, Trystan Leng, uses the data to help in this article. It reports on research that looks for “silver bullet strategies”, control strategies for schools that stem the spread of the disease and simultaneously reduce pupil absences.
Disease modelling for beginners
Find out more about how maths helps us understand how diseases spread in this collection of easy introductions.
What is it like to be an epidemiologist?
Contagious maths
How does maths help in tackling infectious diseases? Join Julia Gog to find out in this series of videos and articles, and have a go at modelling diseases yourself!
Meet the researchers!
Watch these videos to find out about the real research questions that Julia and some of her colleagues are working on!
This article is part of our collaboration with JUNIPER, the Joint UNIversities Pandemic and Epidemiological Research network. JUNIPER is a collaborative network of researchers from across the UK who work at the interface between mathematical modelling, infectious disease control and public health policy. You can see more content produced with JUNIPER here.
