Surveillance is often discussed in technical terms: case definitions, notification thresholds, data quality, timeliness. These matter. But behind every case report is a human decision. A community member decided to seek care. A health worker decided to investigate and report. A supervisor decided to act on the information rather than bury it.
Each of these decisions is influenced by trust. Trust in the health system. Trust that reporting will lead to response, not just paperwork. Trust that the information collected will be used to protect the community, not punish it.
When I worked on disease surveillance in Nigeria, I encountered communities where that trust had eroded. Families who had seen health teams arrive, collect samples, and leave without any feedback or follow-up. Communities where the last disease response had involved quarantine and property restrictions with no compensation. People who associated the surveillance system not with protection but with intrusion.
In those settings, surveillance did not work. Not because the system lacked technology or trained personnel, but because the social contract on which it depends had been broken.
Rebuilding that contract is slow. It requires consistent feedback loops: when a community member reports a suspected case, they should learn what happened to that report. It requires visible follow-through: when surveillance data triggers a response, the community should see that response happen. It requires engagement before crises: surveillance systems that only interact with communities during outbreaks will always struggle to mobilise community participation when they need it most.
The COVID-19 pandemic demonstrated this at scale. Countries with pre-existing community health worker networks and functional community surveillance structures had advantages that could not be rapidly improvised. The investment in community trust, made over years before the pandemic, paid dividends during it.
Surveillance is not just a technical infrastructure. It is a relationship between a health system and the communities it is supposed to serve. Like any relationship, it requires ongoing investment to remain functional.