Surveillance is critical to improving public health in relation to infectious diseases, but it can be made difficult by under reporting, language barriers and logistical issues.
Researchers took a digital epidemiological approach and looked at Google search queries for ‘chicken pox’ over an 11-year period in 36 countries. They found that Google Trends data can act as a proxy for disease incidence and that real-time data can predict the timing and severity of seasonal outbreaks.
Reporting in PNAS (online, 31 May 2016)
, the team also found that countries implementing public varicella zoster virus (VSV) vaccination programmes showed significantly reduced seasonality in Google Trends data compared with other countries.
The authors say that the findings highlight the potential of digital epidemiology as an additional surveillance tool, as well as the population-level impact of VZV vaccination.