Table 3. Clinical manifestations of MM cases under 1 year of age by serogroup.

Symptom	Serogroup A (N=26)	Serogroup B (N=106)	Serogroup C (N=12)	Serogroup W (N=2)	Serogroup Y (N=2)	Non-groupable (N=62)	P*
Note: N/A means data missing or unreported. Abbreviation: MM=meningococcal meningitis. * Hypothesis testing was performed using Fisher’s exact test.
Fever (n, %)
Yes	23 (88.46)	102 (96.23)	12 (100.00)	2 (100.00)	2 (100.00)	59 (95.16)	0.486
No	3 (11.54)	4 (3.77)	0 (0)	0 (0)	0 (0)	3 (4.84)
N/A	0 (0)	0 (0)	0 (0)	0 (0)	0 (0)	0 (0)
Nausea and/or vomiting (n, %)
Yes	14 (53.85)	40 (37.74)	7 (58.33)	1 (50.00)	1 (50.00)	36 (58.06)	0.240
No	7 (26.92)	48 (45.28)	4 (33.33)	1 (50.00)	1 (50.00)	15 (24.19)
N/A	5 (19.23)	18 (16.98)	1 (8.33)	0 (0)	0 (0)	11 (17.74)
Seizure (n, %)
Yes	8 (30.77)	32 (30.19)	4 (33.33)	0 (0)	1 (50.00)	27 (43.55)	0.604
No	14 (53.85)	67 (63.21)	7 (58.33)	2 (100.00)	1 (50.00)	31 (50.00)
N/A	4 (15.38)	7 (6.60)	1 (8.33)	0 (0)	0 (0)	4 (6.45)
Petechiae and/or purpura (n, %)
Yes	19 (73.08)	28 (26.42)	11 (91.67)	1 (50.00)	0 (0)	24 (38.71)	<0.001
No	1 (3.85)	16 (15.09)	0 (0)	0 (0)	0 (0)	7 (11.29)
N/A	6 (23.08)	62 (58.49)	1 (8.33)	1 (50.00)	2 (100.00)	31 (50.00)
Consciousness disorder (n, %)
Yes	11 (42.31)	33 (31.13)	6 (50.00)	2 (100.00)	0 (0)	20 (32.26)	0.434
No	14 (53.85)	59 (55.66)	6 (50.00)	0 (0)	2 (100.00)	32 (51.61)
N/A	1 (3.85)	14 (13.21)	0 (0)	0 (0)	0 (0)	10 (16.13)
Opisthotonus (n, %)
Yes	3 (11.54)	5 (4.72)	0 (0)	0 (0)	0 (0)	4 (6.45)	0.414
No	18 (69.23)	90 (84.91)	9 (75.00)	2 (100.00)	2 (100.00)	54 (87.10)
N/A	5 (19.23)	11 (10.38)	3 (25.00)	0 (0)	0 (0)	4 (6.45)
Bulging fontanelle (n, %)
Yes	8 (30.77)	41 (38.68)	1 (8.33)	1 (50.00)	1 (50.00)	19 (30.65)	0.118
No	15 (57.69)	64 (60.38)	11 (91.67)	1 (50.00)	1 (50.00)	41 (66.13)
N/A	3 (11.54)	1 (0.94)	0 (0)	0 (0)	0 (0)	2 (3.23)
Nuchal rigidity (n, %)
Yes	8 (30.77)	28 (26.42)	4 (33.33)	1 (50.00)	1 (50.00)	26 (41.94)	0.165
No	16 (61.54)	72 (67.92)	5 (41.67)	1 (50.00)	1 (50.00)	34 (54.84)
N/A	2 (7.69)	6 (5.66)	3 (25.00)	0 (0)	0 (0)	2 (3.23)
Kernig and/or Brudzinski signs (n, %)
Yes	3 (11.54)	14 (13.21)	0 (0)	0 (0)	0 (0)	8 (12.90)	0.628
No	16 (61.54)	80 (75.47)	10 (83.33)	2 (100.00)	2 (100.00)	48 (77.42)
N/A	7 (26.92)	12 (11.32)	2 (16.67)	0 (0)	0 (0)	6 (9.68)