How can you avoid catching swine flu? It may be as simple as staying at home and watching TV, scientists say. Simple measures such as staying inside and watching TV can help combat potential flu epidemics, a new study has found. Non-pharmaceutical interventions (NPIs) include actions individuals can take to reduce disease spread, such as hand washing and minimising contacts with sick people. These can play a key role in reducing the spread of infectious diseases such as influenza, according to research published in the journal BMC Infectious Diseases. Social distancing, staying indoors and avoiding social activity, is an important NPI in the event of an epidemic, especially when a vaccine is unavailable or limited. Whether privately initiated or policy directed, NPIs calling for the closure of schools and entertainment venues, and cancelling public events are becoming more relevant in control strategies, researchers said. "The swine flu outbreak that hit Mexico City in April 2009 could have been worse, but spread of the virus was reduced by people's behavioural response of distancing themselves from each other," said University of California at Davis economist Michael Springborn, lead author of the study. The study drew on the combined disciplinary strengths of epidemiology and economics to create a new model that incorporates behavioural responses into existing models of disease spread. Researchers from University of California, Arizona State University, Georgia State University, and Yale University used home television viewing in Central Mexico as an indicator of behavioural response during the pandemic. Television ratings data are consistently and widely available and "highly correlated with time spent in the home," said Springborn. These data provide a good indicator for the level of social interaction, because time spent watching television generally increases with time spent at home. When people are home, they are limiting the number of contacts they make. "We found that the behavioural response to the outbreak was initially strong but waned sooner than expected," said Springborn. This dynamic is interpreted as a "rebound effect". At the onset of a flu outbreak, the public responds strongly to the directed control policies. After a prolonged period of staying indoors people began to spend less time in the confines of their homes. "This suggests that efforts to utilise social distancing to mitigate disease spread may have a limited window of efficacy, ie before pent up-demand for activities outside the home takes precedence," Springborn said. There is historical evidence for this behaviour. Observations from the 1918 influenza pandemic in Australia showed that when the perceived risk decreased the public reverted back to normal behaviour.