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Last update
20 Jul 2026 · 12:49 UTC
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2026 Nigeria Lassa fever season

Active
Jan 5, 2026 – OngoingNigeriaLineage: Lineage II

About this outbreak

Nigeria's 2026 dry-season Lassa fever outbreak, the country's annual epidemic amplified by the Natal multimammate mouse (Mastomys natalensis). Confirmed cases climbed through a January–early-April peak (epi weeks 3–13) concentrated in Ondo, Edo, Bauchi, Taraba and Benue states, with the Irrua Specialist Teaching Hospital (Edo) and the Federal Medical Centre / FUTA treatment centres in Owo and Akure (Ondo) as the epicentres, before tapering into the mid-year low-transmission tail. Dominated by Lassa virus Lineage II, with Lineage III in the north-central states. NCDC coordinated the response with WHO and partners; the case fatality rate held around 25% among confirmed cases.

Outbreak story

Editorial

A curated, narrated reconstruction of how this outbreak unfolded — editorial, not live surveillance. Each point links to its source.

Epidemic curve

Daily new confirmed cases and deaths over time, with a 7-day trailing average and cumulative totals.

Jan 4, 2026 – Jul 16, 2026

Cases in range

807

Deaths in range

207

Peak daily cases

52 on Feb 9

Daily new cases

  • Daily
  • 7-day average
100500
Jan 4Apr 10Jul 16
Daily new cases
DateDaily7-day average
Jan 4, 202600
Jan 5, 202600
Jan 6, 202600
Jan 7, 202600
Jan 8, 202600
Jan 9, 202600
Jan 10, 202600
Jan 11, 202600
Jan 12, 2026284
Jan 13, 202604
Jan 14, 202604
Jan 15, 202604
Jan 16, 202604
Jan 17, 202604
Jan 18, 202604
Jan 19, 2026304.3
Jan 20, 202604.3
Jan 21, 202604.3
Jan 22, 202604.3
Jan 23, 202604.3
Jan 24, 202604.3
Jan 25, 202604.3
Jan 26, 2026223.1
Jan 27, 202603.1
Jan 28, 202603.1
Jan 29, 202603.1
Jan 30, 202603.1
Jan 31, 202603.1
Feb 1, 202603.1
Feb 2, 2026263.7
Feb 3, 202603.7
Feb 4, 202603.7
Feb 5, 202603.7
Feb 6, 202603.7
Feb 7, 202603.7
Feb 8, 202603.7
Feb 9, 2026527.4
Feb 10, 202607.4
Feb 11, 20262410.9
Feb 12, 2026010.9
Feb 13, 2026010.9
Feb 14, 2026010.9
Feb 15, 2026010.9
Feb 16, 2026449.7
Feb 17, 202609.7
Feb 18, 202606.3
Feb 19, 202606.3
Feb 20, 202606.3
Feb 21, 202606.3
Feb 22, 202606.3
Feb 23, 2026344.9
Feb 24, 202604.9
Feb 25, 202604.9
Feb 26, 202604.9
Feb 27, 2026207.7
Feb 28, 202607.7
Mar 1, 202607.7
Mar 2, 2026307.1
Mar 3, 202607.1
Mar 4, 202607.1
Mar 5, 202607.1
Mar 6, 2026247.7
Mar 7, 202607.7
Mar 8, 202607.7
Mar 9, 20264610
Mar 10, 2026010
Mar 11, 2026010
Mar 12, 2026010
Mar 13, 2026189.1
Mar 14, 202609.1
Mar 15, 202609.1
Mar 16, 2026408.3
Mar 17, 202608.3
Mar 18, 202608.3
Mar 19, 202608.3
Mar 20, 202605.7
Mar 21, 202605.7
Mar 22, 202605.7
Mar 23, 2026304.3
Mar 24, 202604.3
Mar 25, 202604.3
Mar 26, 202604.3
Mar 27, 2026146.3
Mar 28, 202606.3
Mar 29, 202606.3
Mar 30, 2026286
Mar 31, 202606
Apr 1, 202606
Apr 2, 202606
Apr 3, 202604
Apr 4, 202604
Apr 5, 202604
Apr 6, 2026223.1
Apr 7, 202603.1
Apr 8, 202603.1
Apr 9, 202603.1
Apr 10, 2026165.4
Apr 11, 202605.4
Apr 12, 202605.4
Apr 13, 2026387.7
Apr 14, 202607.7
Apr 15, 202607.7
Apr 16, 202607.7
Apr 17, 2026127.1
Apr 18, 202607.1
Apr 19, 202607.1
Apr 20, 2026346.6
Apr 21, 202606.6
Apr 22, 202606.6
Apr 23, 202606.6
Apr 24, 2026167.1
Apr 25, 202607.1
Apr 26, 202607.1
Apr 27, 2026205.1
Apr 28, 202605.1
Apr 29, 202605.1
Apr 30, 202605.1
May 1, 202602.9
May 2, 202602.9
May 3, 202602.9
May 4, 2026121.7
May 5, 202601.7
May 6, 202601.7
May 7, 202601.7
May 8, 202601.7
May 9, 202601.7
May 10, 202601.7
May 11, 2026223.1
May 12, 202603.1
May 13, 202603.1
May 14, 202603.1
May 15, 202603.1
May 16, 202603.1
May 17, 202603.1
May 18, 2026202.9
May 19, 202602.9
May 20, 202602.9
May 21, 202602.9
May 22, 202602.9
May 23, 202602.9
May 24, 202602.9
May 25, 2026182.6
May 26, 202602.6
May 27, 202602.6
May 28, 202602.6
May 29, 202602.6
May 30, 202602.6
May 31, 202602.6
Jun 1, 2026142
Jun 2, 202602
Jun 3, 202602
Jun 4, 202602
Jun 5, 202602
Jun 6, 202602
Jun 7, 202602
Jun 8, 2026131.9
Jun 9, 202601.9
Jun 10, 202601.9
Jun 11, 202601.9
Jun 12, 202601.9
Jun 13, 202601.9
Jun 14, 202601.9
Jun 15, 2026142
Jun 16, 202602
Jun 17, 202602
Jun 18, 202602
Jun 19, 202602
Jun 20, 202602
Jun 21, 202602
Jun 22, 2026121.7
Jun 23, 202601.7
Jun 24, 202601.7
Jun 25, 202601.7
Jun 26, 202601.7
Jun 27, 202601.7
Jun 28, 202601.7
Jun 29, 202600
Jun 30, 202600
Jul 1, 202600
Jul 2, 202600
Jul 3, 202600
Jul 4, 202600
Jul 5, 202600
Jul 6, 202681.1
Jul 7, 202601.1
Jul 8, 202601.1
Jul 9, 202601.1
Jul 10, 202601.1
Jul 11, 202601.1
Jul 12, 202601.1
Jul 13, 202600
Jul 14, 202600
Jul 15, 202600
Jul 16, 202660.9

Daily new deaths

  • Daily
  • 7-day average
20100
Jan 4Apr 10Jul 16
Daily new deaths
DateDaily7-day average
Jan 4, 202600
Jan 5, 202600
Jan 6, 202600
Jan 7, 202600
Jan 8, 202600
Jan 9, 202600
Jan 10, 202600
Jan 11, 202600
Jan 12, 202660.9
Jan 13, 202600.9
Jan 14, 202600.9
Jan 15, 202600.9
Jan 16, 202600.9
Jan 17, 202600.9
Jan 18, 202600.9
Jan 19, 202681.1
Jan 20, 202601.1
Jan 21, 202601.1
Jan 22, 202601.1
Jan 23, 202601.1
Jan 24, 202601.1
Jan 25, 202601.1
Jan 26, 202650.7
Jan 27, 202600.7
Jan 28, 202600.7
Jan 29, 202600.7
Jan 30, 202600.7
Jan 31, 202600.7
Feb 1, 202600.7
Feb 2, 202681.1
Feb 3, 202601.1
Feb 4, 202601.1
Feb 5, 202601.1
Feb 6, 202601.1
Feb 7, 202601.1
Feb 8, 202601.1
Feb 9, 2026101.4
Feb 10, 202601.4
Feb 11, 202672.4
Feb 12, 202602.4
Feb 13, 202602.4
Feb 14, 202602.4
Feb 15, 202602.4
Feb 16, 2026112.6
Feb 17, 202602.6
Feb 18, 202601.6
Feb 19, 202601.6
Feb 20, 202601.6
Feb 21, 202601.6
Feb 22, 202601.6
Feb 23, 202691.3
Feb 24, 202601.3
Feb 25, 202601.3
Feb 26, 202601.3
Feb 27, 202662.1
Feb 28, 202602.1
Mar 1, 202602.1
Mar 2, 202692.1
Mar 3, 202602.1
Mar 4, 202602.1
Mar 5, 202602.1
Mar 6, 202672.3
Mar 7, 202602.3
Mar 8, 202602.3
Mar 9, 202692.3
Mar 10, 202602.3
Mar 11, 202602.3
Mar 12, 202602.3
Mar 13, 202652
Mar 14, 202602
Mar 15, 202602
Mar 16, 2026102.1
Mar 17, 202602.1
Mar 18, 202602.1
Mar 19, 202602.1
Mar 20, 202601.4
Mar 21, 202601.4
Mar 22, 202601.4
Mar 23, 202681.1
Mar 24, 202601.1
Mar 25, 202601.1
Mar 26, 202601.1
Mar 27, 202641.7
Mar 28, 202601.7
Mar 29, 202601.7
Mar 30, 202681.7
Mar 31, 202601.7
Apr 1, 202601.7
Apr 2, 202601.7
Apr 3, 202601.1
Apr 4, 202601.1
Apr 5, 202601.1
Apr 6, 202671
Apr 7, 202601
Apr 8, 202601
Apr 9, 202601
Apr 10, 202661.9
Apr 11, 202601.9
Apr 12, 202601.9
Apr 13, 202682
Apr 14, 202602
Apr 15, 202602
Apr 16, 202602
Apr 17, 202641.7
Apr 18, 202601.7
Apr 19, 202601.7
Apr 20, 202691.9
Apr 21, 202601.9
Apr 22, 202601.9
Apr 23, 202601.9
Apr 24, 202652
Apr 25, 202602
Apr 26, 202602
Apr 27, 202651.4
Apr 28, 202601.4
Apr 29, 202601.4
Apr 30, 202601.4
May 1, 202600.7
May 2, 202600.7
May 3, 202600.7
May 4, 202640.6
May 5, 202600.6
May 6, 202600.6
May 7, 202600.6
May 8, 202600.6
May 9, 202600.6
May 10, 202600.6
May 11, 202640.6
May 12, 202600.6
May 13, 202600.6
May 14, 202600.6
May 15, 202600.6
May 16, 202600.6
May 17, 202600.6
May 18, 202650.7
May 19, 202600.7
May 20, 202600.7
May 21, 202600.7
May 22, 202600.7
May 23, 202600.7
May 24, 202600.7
May 25, 202650.7
May 26, 202600.7
May 27, 202600.7
May 28, 202600.7
May 29, 202600.7
May 30, 202600.7
May 31, 202600.7
Jun 1, 202630.4
Jun 2, 202600.4
Jun 3, 202600.4
Jun 4, 202600.4
Jun 5, 202600.4
Jun 6, 202600.4
Jun 7, 202600.4
Jun 8, 202640.6
Jun 9, 202600.6
Jun 10, 202600.6
Jun 11, 202600.6
Jun 12, 202600.6
Jun 13, 202600.6
Jun 14, 202600.6
Jun 15, 202630.4
Jun 16, 202600.4
Jun 17, 202600.4
Jun 18, 202600.4
Jun 19, 202600.4
Jun 20, 202600.4
Jun 21, 202600.4
Jun 22, 202620.3
Jun 23, 202600.3
Jun 24, 202600.3
Jun 25, 202600.3
Jun 26, 202600.3
Jun 27, 202600.3
Jun 28, 202600.3
Jun 29, 202600
Jun 30, 202600
Jul 1, 202600
Jul 2, 202600
Jul 3, 202600
Jul 4, 202600
Jul 5, 202600
Jul 6, 202620.3
Jul 7, 202600.3
Jul 8, 202600.3
Jul 9, 202600.3
Jul 10, 202600.3
Jul 11, 202600.3
Jul 12, 202600.3
Jul 13, 202600
Jul 14, 202600
Jul 15, 202600
Jul 16, 202610.1

Cumulative totals

  • Cumulative cases
  • Cumulative deaths
1,0005000
Jan 4Apr 10Jul 16
Cumulative totals
DateCumulative casesCumulative deaths
Jan 4, 202600
Jan 5, 202600
Jan 6, 202600
Jan 7, 202600
Jan 8, 202600
Jan 9, 202600
Jan 10, 202600
Jan 11, 202600
Jan 12, 2026286
Jan 13, 2026286
Jan 14, 2026286
Jan 15, 2026286
Jan 16, 2026286
Jan 17, 2026286
Jan 18, 2026286
Jan 19, 20265814
Jan 20, 20265814
Jan 21, 20265814
Jan 22, 20265814
Jan 23, 20265814
Jan 24, 20265814
Jan 25, 20265814
Jan 26, 20268019
Jan 27, 20268019
Jan 28, 20268019
Jan 29, 20268019
Jan 30, 20268019
Jan 31, 20268019
Feb 1, 20268019
Feb 2, 202610627
Feb 3, 202610627
Feb 4, 202610627
Feb 5, 202610627
Feb 6, 202610627
Feb 7, 202610627
Feb 8, 202610627
Feb 9, 202615837
Feb 10, 202615837
Feb 11, 202618244
Feb 12, 202618244
Feb 13, 202618244
Feb 14, 202618244
Feb 15, 202618244
Feb 16, 202622655
Feb 17, 202622655
Feb 18, 202622655
Feb 19, 202622655
Feb 20, 202622655
Feb 21, 202622655
Feb 22, 202622655
Feb 23, 202626064
Feb 24, 202626064
Feb 25, 202626064
Feb 26, 202626064
Feb 27, 202628070
Feb 28, 202628070
Mar 1, 202628070
Mar 2, 202631079
Mar 3, 202631079
Mar 4, 202631079
Mar 5, 202631079
Mar 6, 202633486
Mar 7, 202633486
Mar 8, 202633486
Mar 9, 202638095
Mar 10, 202638095
Mar 11, 202638095
Mar 12, 202638095
Mar 13, 2026398100
Mar 14, 2026398100
Mar 15, 2026398100
Mar 16, 2026438110
Mar 17, 2026438110
Mar 18, 2026438110
Mar 19, 2026438110
Mar 20, 2026438110
Mar 21, 2026438110
Mar 22, 2026438110
Mar 23, 2026468118
Mar 24, 2026468118
Mar 25, 2026468118
Mar 26, 2026468118
Mar 27, 2026482122
Mar 28, 2026482122
Mar 29, 2026482122
Mar 30, 2026510130
Mar 31, 2026510130
Apr 1, 2026510130
Apr 2, 2026510130
Apr 3, 2026510130
Apr 4, 2026510130
Apr 5, 2026510130
Apr 6, 2026532137
Apr 7, 2026532137
Apr 8, 2026532137
Apr 9, 2026532137
Apr 10, 2026548143
Apr 11, 2026548143
Apr 12, 2026548143
Apr 13, 2026586151
Apr 14, 2026586151
Apr 15, 2026586151
Apr 16, 2026586151
Apr 17, 2026598155
Apr 18, 2026598155
Apr 19, 2026598155
Apr 20, 2026632164
Apr 21, 2026632164
Apr 22, 2026632164
Apr 23, 2026632164
Apr 24, 2026648169
Apr 25, 2026648169
Apr 26, 2026648169
Apr 27, 2026668174
Apr 28, 2026668174
Apr 29, 2026668174
Apr 30, 2026668174
May 1, 2026668174
May 2, 2026668174
May 3, 2026668174
May 4, 2026680178
May 5, 2026680178
May 6, 2026680178
May 7, 2026680178
May 8, 2026680178
May 9, 2026680178
May 10, 2026680178
May 11, 2026702182
May 12, 2026702182
May 13, 2026702182
May 14, 2026702182
May 15, 2026702182
May 16, 2026702182
May 17, 2026702182
May 18, 2026722187
May 19, 2026722187
May 20, 2026722187
May 21, 2026722187
May 22, 2026722187
May 23, 2026722187
May 24, 2026722187
May 25, 2026740192
May 26, 2026740192
May 27, 2026740192
May 28, 2026740192
May 29, 2026740192
May 30, 2026740192
May 31, 2026740192
Jun 1, 2026754195
Jun 2, 2026754195
Jun 3, 2026754195
Jun 4, 2026754195
Jun 5, 2026754195
Jun 6, 2026754195
Jun 7, 2026754195
Jun 8, 2026767199
Jun 9, 2026767199
Jun 10, 2026767199
Jun 11, 2026767199
Jun 12, 2026767199
Jun 13, 2026767199
Jun 14, 2026767199
Jun 15, 2026781202
Jun 16, 2026781202
Jun 17, 2026781202
Jun 18, 2026781202
Jun 19, 2026781202
Jun 20, 2026781202
Jun 21, 2026781202
Jun 22, 2026793204
Jun 23, 2026793204
Jun 24, 2026793204
Jun 25, 2026793204
Jun 26, 2026793204
Jun 27, 2026793204
Jun 28, 2026793204
Jun 29, 2026793204
Jun 30, 2026793204
Jul 1, 2026793204
Jul 2, 2026793204
Jul 3, 2026793204
Jul 4, 2026793204
Jul 5, 2026793204
Jul 6, 2026801206
Jul 7, 2026801206
Jul 8, 2026801206
Jul 9, 2026801206
Jul 10, 2026801206
Jul 11, 2026801206
Jul 12, 2026801206
Jul 13, 2026801206
Jul 14, 2026801206
Jul 15, 2026801206
Jul 16, 2026807207

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