Table 2.

Frequency of bacterial isolates by grade level among asymptomatic primary school children in Debre Berhan town, North Shewa, Ethiopia, February 1 to April 30, 2021

Grade level of children
Isolated bacteria species	Grade 1	Grade 2	Grade 3	Grade 4	Grade 5	Grade 6	Grade 7	Grade 8	Total (n/%)
S. aureus = n (%)	12 (16.4)	10 (13.7)	19 (26.07)	11 (15.1)	5 (6.8)	6 (8.2)	5 (6.8)	5 (6.8)	73 (53.3)
CoNS = n (%)	2 (10)	4 (20)	3 (15)	2 (20)	3 (15)	2 (10)	2 (10)	2 (10)	20 (14.6)
S. pyogens = n (%)	2 (20)	1 (10)	2 (20)	2 (20)	1 (10)	1 (10)	1 (10)	0 (0.0)	10 (7.3)
K. pneumoniae = n (%)	1 (10.)	1 (10)	3 (30)	1 (10)	2 (20)	1 (10)	(0.0)	1 (10)	10 (7.3)
H. Influenzae = n (%)	2 (22.2)	1 (11.1)	2 (22.2)	3 (33.3)	1 (11.1)	0 (0.0)	0 (0.0)	0 (0.0)	9 (6.6)
K. rhinoscleromatis = n (%)	0 (0.0)	2 (22.2)	1 (11.1)	2 (22.2)	3 (33.3)	1 (11.1)	2 (22.2)	0 (0.0)	9 (6.6)
K. oxytoca = n (%)	2 (33.3)	0 (0)	2 (33.3)	1 (16.7)	1 (16.7)	0 (0)	0 (0)	0 (0)	6 (4.4)
Total = n (%)	21 (15.3)	19 (13.9)	32 (23.4)	22 (16.1)	16 (11.7)	11 (8.02)	12 (9.0)	7 (5.1)	137 (100)

CoNS Coagulase negative Staphylococcus