Table 1.

Basic parameters on the included subjects

Parameter	Exposed	Non exposed
	n = 83	n = 79
Age: mean (SD)	13.7 (10.1)	13.2 (7.55)
Sex:
- Male: n (%)	44 (53.0)	38 (48.1)
Etiological agent by PCR or Latex:
- N. meningitidis: n (%)	78 (94)	0
Serogroup W135	72 (86.7)	0
Location:
- Niamey: n (%)	53 (63.9)	52 (65.8)