Reported lassa fever surveillance for Sierra Leone (SLE) — — latest record 2026-10-07
The latest report for Sierra Leone gives an outbreak total of 1 lassa fever cases to date. That is a running total since the outbreak began, not a count for 2026. No 2025 figure has been reported.
ENCLAI has logged 5 surveillance records for lassa fever in Sierra Leone in 2026, with the most detailed reporting in Oct 2026 (2 records); the case counts run to 2026-03-15. 3 distinct surveillance sources reported this pair in 2026.
Reporting authorities for these counts: WHO AFRO Weekly Bulletin — cumulative suspected cases · WHO AFRO Weekly Bulletin on Outbreaks and Other Emergencies
One email a day: what changed in official disease reporting worldwide, with the source named for every number. Reported facts only — no forecasts and no interpretation.
| Year | Reported cases | Share of worldwide reports |
|---|---|---|
| 2023 | not reported | — |
| 2024 | not reported | — |
| 2025 | not reported | — |
| 2026 (year to date) | 1 (outbreak total to date) | — |
Reporting bounds and case definitions vary; historical baselines are a separate comparison measure. Worldwide share compares this country's reported figure with the sum of all countries reporting lassa fever to ENCLAI for that year. "Incomplete year" means our sources cover less than ten months of that year, so no full-year figure is shown; "outbreak total to date" is a running total since an outbreak began, not a count for one year.
| Month | Records | Reporting sources |
|---|---|---|
| May 2026 | 1 | 1 |
| Jun 2026 | 1 | 1 |
| Sep 2026 | 1 | 1 |
| Oct 2026 | 2 | 1 |
A record is one dated surveillance publication or one row of an official table; a month with many records is a month with detailed reporting, not necessarily more cases.
| Country | 2026 cases | Trend |
|---|---|---|
| Nigeria | 1,138 | |
| Liberia | 249 | |
| Guinea | 4 (outbreak total to date) |
| Disease | 2026 cases | Trend |
|---|---|---|
| Mpox (monkeypox) | 5,442 (outbreak total to date) | |
| Dengue fever | 1 (outbreak total to date) |
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One email a day: what changed in official disease reporting worldwide, with the source named for every number. Reported facts only — no forecasts and no interpretation.
