Sledilnik in Action: Fighting COVID-19 with Open Source
When Slovenia confirmed its first official case of COVID-19 on 4 March 2020, one citizen (Luka Renko) quietly began collecting data, not as a government official or academic, but as an individual with asthma concerned about a looming respiratory threat. He then initiated Sledilnik, the Slovenian volunteer project that used open source solutions to collect, publish and digitally organise COVID-19 data from various public sector sources. Luka stepped in to fill a gap left by the Slovenian public sector, which was not publishing its COVID-19 data and was gathering them only on paper. After gaining the attention of the authorities, the National Institute of Public Health (NIJZ) began cooperating with the Sledilnik team, providing data in the structured format the team required.
Sledilnik’s origin story and gradual success
Because official briefings lacked clear data, people struggled to understand the situation and protect themselves from the pandemic. One of them was Luka. He started entering case numbers into a spreadsheet, analysing patterns to understand whether the virus was spreading exponentially or remaining linear. Within days, he posted his tables to Twitter. The response was immediate. Others joined him, first individuals, then local media and medical professionals from across Slovenia and what began as a solo initiative quickly grew into a nationwide community and collaborative effort: the COVID-19 Tracker- Sledilnik.
Despite institutional resistance, the team collected hospital and wastewater data, essential for understanding national COVID-19 trends. By the third week, the community attracted over 250 contributors, with experts across disciplines universities and public hospitals, working daily to provide, organise, visualise, and communicate vital information. Sledilnik operated without hierarchy, as people contributed based on expertise and initiative. The tracker’s data became a major public resource, peaking at a million unique monthly users in a country of two million, and even outperformed major search topics on Google.
It also contributed to improving policies For example, it pushed for better data infrastructure as the NIJZ transitioned from paper-based to digital data collection and to better trust in the institutions. Sledilnik filled that gap by systematically compiling and processing hospitalisation figures, offering policymakers near real-time insights they otherwise lacked. This not only increased situational awareness but also demonstrated the urgent need for digitalisation in the healthcare system, which laid the groundwork for more resilient systems in case of future health crises.
Tracking the Virus, Empowering the Public
The story of Sledilnik proves that open source solutions can be enablers of collaborative volunteering, driving digital innovation and transformation. This experience also highlighted the need for transparency and the transformative potential of open data, the vital role that their openness brings to trust and transparent communication in times of crisis, alongside the need for resilient digital infrastructure. Sledilnik stands as a testament to what committed individuals can achieve by filling the gaps, supporting institutions, and demonstrating how open source and open data can amplify public capabilities.
Although Sledilnik’s regular updates ended in August 2024, the community remains active, now focusing the platform on health access data and potentially shifting to climate change analysis. What began as a COVID-19 tracking tool is evolving into a broader civic tech platform, potentially applying its open source, data-driven model to new public health and environmental challenges.
For more technical information on the different functionalities of Sledilnik like data on doctors’ availability and the licence that the solution uses click on its GitHub page.
Sources
- https://covid-19.sledilnik.org/sl/stats
- https://www.rtvslo.si/zdravje/pet-let-pozneje/luka-renko-v-letu-2021-je-sledilnik-po-stevilu-iskanj-prehitel-vreme-in-evrosong/738224
Image taken from here