The novel coronavirus is still spreading across the world without a treatment. As a response, governments have implemented strict measures to minimise its harmful effects and slow down the spread of the disease it causes, called COVID-19. Globally, countries have closed borders, schools and businesses, limited traffic and transport, encouraged physical distancing, and even imposed lockdown measures. Now as the spread of the virus seems to be slowing down, countries have started to ease their measures.
Professor Graham Medley, Professor of Infectious Disease Modelling and Director of the Centre for the Mathematical Modelling of Infectious Diseases (CMMID) at the London School of Hygiene and Tropical Medicine, UK: “Generally infectious disease patterns in a population, the epidemiology, is determined by a combination of the biology of the pathogen, the environment, and the behaviour of the population. Of particular interest are the networks that behaviour creates, which allow transmission from one person to create chains of transmission that connect the whole population. The structure and shape of these networks largely determine who is at greatest risk of infection and the scale and shape of the epidemic.”
Like many respiratory viruses, the new coronavirus spreads through droplets released from the nose or mouth of an infected person as they cough, sneeze or speak. These droplets can land on other people, clothing, objects and surfaces around them. A quick review suggests that 13 behaviours are key to reducing its transmission, from hand hygiene to physical distancing. Many strategies exist to change people’s transmission-related behaviours and slow down the virus, says Professor Susan Michie at University College London. The behaviours of various actors are crucial, including those of governments, businesses, the media, and community groups.
Professor Susan Michie, Professor of Health Psychology and Director of the Centre for Behaviour Change at University College London (UCL), UK: “The first step to changing behaviour is to understand behaviour in its context, meaning that behavioural science should be at the heart of efforts to reduce disease transmission, and, indeed, all threats to health, the environment and society.”
A framework for understanding and changing behaviour is the COM-B model, which states that in order to arrive at a particular and desired behaviour, people need to have the capability, opportunity and motivation (COM). Behaviour change will not happen unless all three of those are in place, says Professor Michie. Governments and health authorities can use this model to implement effective interventions and supporting policies, whilst encouraging the public to behave accordingly. However, she adds, it is important to tailor these to particular groups and contexts, as well as the available evidence.
To study the impact that human behaviour has on the spread of epidemics, behaviour is integrated in mathematical models for infectious diseases. In general, models can be helpful tools to make predictions about a disease, its spread, and effects of various interventions and policies. For example, based on modelling by Imperial College, the UK government changed its initial ‘herd immunity’ policy to implementing quarantine and social distancing during COVID-19. The same team also used a model to make predictions about the disease in 11 European countries. Others are now comparing containment measures worldwide to find the most effective policies that could further prevent a second wave.
Although no model is perfect, as there are too many variables in the real world, Professor Medley notes that the best models include human behaviour data which contain realistic networks. Data can include basic demography, such as the number and size of households or schools, and the results of contact and time usage. The better the data, the more accurate the model is at representing the real world.
But there are also limitations to such models. “What we cannot yet do in models is to accurately predict human behaviour. Consequently, model output can only be in the form of ‘If 50% of people stop going to work, then…’. Policy-makers then have to determine policies that achieve behaviour change they require,” says Professor Medley.
Adhering to health messages
According to Professor Michie, “people’s decisions and behaviours will be influenced by the extent to which they think there is a threat and the extent to which they think they can do anything to mitigate it.” In 1992, Professor Kim Witte developed a health risk message model which predicts how people, when faced with a perceived threat, will respond to messages. It is commonly used in health communication to persuade the public to adopt healthy behaviours, explains Professor Enny Das.
Professor Enny Das, Professor of Communication and Persuasion, and Principle Investigator of the Persuasive Communication Research Group of the Centre for Language Studies at Radboud University in Nijmegen, Netherlands: “The risk is usually well-communicated, but often officials fail to communicate how people need to deal with that risk. […] People need to understand that the response recommended is effective in controlling the risk, which should be explicitly mentioned, and people should also be able to carry out the tasks needed. This sounds easy, but the reality is that it is often very difficult for people to understand how exactly they should behave.”
People can often understand the severity of a threat, but underestimate its impact. “With social dilemmas during epidemics, it is very important to stress that each individual’s action affects others and their contribution is making a difference,” says Professor Das. Using storytelling to communicate a message, particularly in a visual form such as video, could help people to better understand how the measures are relevant to them on a personal level and how they can have an impact on the population level. Showing people how to do certain actions, such as washing hands properly, can also be more effective than “just telling people”, she adds.
In times of crises, it is also important that messages are contextualised and communicated honestly, transparently and consistently by trusted sources. “When enough people begin routinely adopting personal protective behaviours and enough messages support these coming from a variety of trusted, high-status sources that people identify with, […] then these behaviours can become a cultural and social norm. When we take a multi-faceted approach to changing behaviours, they can become embedded in our practices,” says Professor Michie.
• WHO: Coronavirus disease (COVID-19) advice for the public
• WHO tool for behavioural insights on COVID-19
• European Commission — COVID-19: 5 ways to help prevent the spread
• Coronavirus: Commission boosts urgently needed research and innovation
• Economic and Social Research Institute (ESRI) report
• Nature Human Behaviour: How behavioural science data helps mitigate the COVID-19 crisis
• Covid-19: Social distancing will help health authorities deal with coronavirus
• Why outbreaks like coronavirus spread exponentially, and how to “flatten the curve”
• Stanford Medicine’s Global COVID-19 Prevention video
• A scientist’s opinion : Interview with Professor Enny Das about health communication and persuasion
• A scientist’s opinion : Interview with Professor Susan Michie about behaviour change amid COVID-19
• A scientist’s opinion : Interview with Professor Graham Medley about mathematical modelling of infectious diseases
• EU project : ECOM
• EU project : MOOD