Table 4.
Quarterly distribution of confirmed cases of Lassa fever in Nigeria, 2009–2018 as seen at Irrua Specialist Teaching Hospital.
| Year | No. (%) of cases in | Total No. (%) | |||
|---|---|---|---|---|---|
| Jan–Mar | Apr–Jun | Jul–Sept | Oct–Dec | ||
| 2009 | 64 (46.7) | 14 (10.2) | 30 (21.9) | 29 (21.2) | 137 (100) |
| 2010 | 36 (47.3) | 10 (13.2) | 14 (18.4) | 16 (21.1) | 76 (100) |
| 2011 | 41 (43.2) | 13 (13.7) | 10 (10.5) | 31 (32.6) | 95 (100) |
| 2012 | 82 (47.7) | 39 (22.7) | 23 (13.3) | 28 (16.3) | 172 (100) |
| 2013 | 95 (68.4) | 17 (12.2) | 10 (7.2) | 17 (12.2) | 139 (100) |
| 2014 | 40 (48.9) | 16 (19.5) | 14 (17.1) | 12 (14.6) | 82 (100) |
| 2015 | 38 (59.7) | 8 (12.5) | 6 (9.4) | 12 (18.7) | 64 (100) |
| 2016 | 113 (74.3) | 13 (8.6) | 9 (5.9) | 17 (11.2) | 152 (100) |
| 2017 | 92 (37.4) | 74 (30.1) | 42 (17.1) | 38 (18.5) | 246 (100) |
| 2018 | 353 (81.9) | 36 (8.4) | 42 (9.7) | NA | 431 (100) |
| Total | 954 (59.9) | 240 (15.1) | 200 (12.5) | 200 (12.5) | 1,594 (100) |
| Median (IQR)*, ** | 48.3 (19.4)%#, @, & | 12.9(7.4)%# | 11.9 (7.6)%@ | 18.5 (6.5)%& | |
Percentages add across. IQR, interquartile range.
*
Median (IQR) of the proportions of cases per quarter.
**
Kruskal-Wallis test for significance of the difference between the medians: χ2 = 18.5, p < 0.001.
Significant differences between medians are indicated by similar symbols:
#
p < 0.001,
@
p < 0.001, and
&
p < 0.001.