Digital Tools for Lassa Fever Surveillance and Outbreak Response in Nigeria: A Focused Scoping Review

Background

Lassa fever remains a persistent public health threat in Nigeria, where recurrent outbreaks place considerable demands on surveillance, laboratory services and outbreak-response capacity. Timely identification of suspected cases is particularly important because delayed notification and laboratory confirmation can impede case management, contact follow-up and infection prevention. Digital surveillance has increasingly been incorporated into Nigeria's response, with the Surveillance Outbreak Response Management and Analysis System (SORMAS) supporting electronic case-based reporting and real-time outbreak monitoring. Evidence on how these digital capabilities have contributed specifically to Lassa fever surveillance, however, remains dispersed across state-level investigations and implementation studies.

Methods

A focused scoping review was undertaken to synthesise evidence on digital technologies used for Lassa fever surveillance and outbreak response in Nigeria. The evidence base was identified from literature published between 2015 and 2026 and searched through PubMed, ScienceDirect, SpringerLink, BMJ Global Health and Google Scholar. Eligible evidence was restricted to studies reporting digital surveillance applications or outcomes directly relevant to Lassa fever in Nigeria. Data were synthesised narratively because of heterogeneity in study designs, settings and reported outcomes. The synthesis examined electronic case-based surveillance, reporting and notification, contact tracing, real-time outbreak monitoring and implementation constraints.

Results

SORMAS was the dominant digital platform identified for Lassa fever surveillance. Evidence was reported from several Nigerian states, including Benue, Kaduna, Anambra, Ebonyi and Cross River. Digital case-based surveillance supported real-time tracking of suspected and confirmed cases and enabled geographical identification of areas with concentrated disease burden. Reported state-level case fatality rates varied substantially, from 24% in Ebonyi to 73.3% in Kaduna, indicating that improved surveillance capability coexisted with considerable mortality. Digital surveillance was also associated with improvements in specific response processes. In Ebonyi, contact-tracing completeness increased from 45% to 85%, while evidence from Cross River reported a five-day reduction in response time following the introduction of real-time alerts. Persistent constraints included unreliable electricity, poor internet connectivity, limited digital literacy, shortages of digital equipment and continued dependence on parallel paper and electronic reporting.

Conclusion

Digital surveillance has strengthened important operational components of Lassa fever surveillance and outbreak response in Nigeria, particularly case-based reporting, real-time monitoring, contact tracing and rapid transmission of surveillance information. The evidence also shows that stronger surveillance does not necessarily translate into low mortality where clinical, laboratory, infrastructural and workforce limitations persist. Digital platforms should therefore be positioned as components of an integrated outbreak-response system rather than stand-alone solutions. Sustained infrastructure, workforce capability, interoperability and long-term financing remain necessary to convert improvements in surveillance intelligence into stronger Lassa fever control.

Lassa fever, digital surveillance, SORMAS, outbreak response, contact tracing, disease surveillance, Nigeria

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