With experts warning that the Coronavirus pandemic may last well into next year, the urgency of limiting the spread of the virus is sure to increase. Cellphone and social media data will increasingly be viewed as a valuable sources of information for public health authorities, as they seek to identify outbreaks in communities more quickly, rapidly warn people that they may have been exposed to the virus, or enforce quarantine orders. My Globe and Mail op-ed notes the data culled from these sources may prove invaluable, but they raise exceptionally difficult challenges of balancing public health concerns with fundamental privacy rights.