Table 1 Sociodemographic and clinical features of norovirus-positive compared to norovirus-negative diarrheal illness episodes in young Zambian children

 Sex

0.240

  Female

14/22 (63.6)

127/257 (49.4)

  Male

8/22 (36.3)

130/257 (50.6)

 Age

0.797

   < 1 month

0 (0.0)

3/266 (1.1)

  1–6 months

2/23 (8.7)

31/266 (11.7)

  6–12 months

10/23 (43.5)

106/266 (39.8)

  12–24 months

9/23 (39.1)

83/266 (31.2)

   > 24 months

2/23 (8.7)

43/266 (16.2)

 Number of siblings

0.867

  0

8/21 (38.1)

69/210 (32.9)

  1

4/21 (19.1)

53/210 (25.2)

  2

4/21 (19.1)

48/210 (22.9)

  3

2/21 (9.5)

17/210 (8.1)

   ≥ 4

3/21 (14.3)

23/210 (11.0)

 Household electricity

15/23 (65.2)

164/258 (63.6)

0.875

 Household drinking water source

0.793

  Communal tap

12/19 (63.1)

110/244 (45.1)

  Piped to yard

3/19 (15.8)

39/244 (16.0)

  Piped into dwelling

2/19 (10.5)

36/244 (14.8)

  Protected public well

1/19 (5.3)

21/244 (8.6)

  River/stream

0/19 (0.0)

14/244 (5.7)

  Other

1/19 (5.3)

24/244 (9.8)

 Household livestock

3/23 (13.0)

28/251 (11.2)

0.784

 Toilet facility

0.031

  Flush/pour flush to piped sewer

1/20 (5.0)

41/225 (18.2)

  Flush/pour flush to septic tank

3/20 (15.0)

42/225 (18.7)

  Flush/pour flush to pit latrine

3/20 (15.0)

3/225 (1.3)

  Improved ventilated pit latrine

1/20 (5.0)

16/225 (7.1)

  Pit latrine with slab

10/20 (50.0)

78/225 (34.7)

  Open pit latrine without slab

2/20 (10.0)

44/225 (19.6)

  Hanging toilet/hanging latrine

0/20 (0.0)

1/225 (0.4)

 Child ever diagnosed with HIV/AIDS

0/18 (0.0)

1/201 (0.5)

1.000

  0 doses or unknown

13/23 (56.5)

171/266 (64.3)

  At least 1 dose

10/23 (43.4)

95/266 (35.7)

0.458

  2 doses

8/23 (34.8)

79/266 (30.0)

0.610

 Severity score by category

0.766

   ≤ 10 (mild)

16/19 (84.2)

156/183 (85.3)

  11–14 (moderate)

3/19 (15.8)

26/183 (14.2)

   ≥ 15 (severe)

0/19 (0.0)

1/183 (0.6)

 Degree of dehydration on admission

0.319

  None

2/23 (8.7)

57/259 (22.0)

  Mild

7/23 (30.4)

55/259 (21.2)

  Moderate

14/23 (60.9)

136/259 (52.5)

  Severe

0/23 (0.0)

11/259 (4.3)

 Duration of diarrhea, days

0.505

  1–4

21/22 (95.5)

203/221 (91.9)

  5

1/22 (4.5)

6/221 (2.7)

   ≥ 6

0/22 (0.0)

12/221 (5.4)

 Max stools/day

0.444

  1–3

14/22 (63.6)

112/217 (51.6)

  4–5

8/22 (36.4)

90/217 (41.5)

   ≥ 6

0/22 (0.0)

15/217 (6.9)

 Blood in stool

0/22 (0.0)

8/216 (3.7)

1.000

 Vomiting

9/21 (42.9)

83/221 (37.1)

0.603

 Duration of vomiting, days

0.593

  0

12/22 (54.6)

139/221 (62.9)

  1

1/22 (4.6)

9/221 (4.1)

  2

5/22 (22.7)

49/221 (22.2)

   ≥ 3

4/22 (18.2)

24/221 (10.9)

 Maximum vomiting episodes/day

0.502

  0

12/22 (54.6)

139/218 (63.8)

  1

0/22 (0.0)

5/218 (2.3)

  2–4

10/22 (45.5)

65/218 (29.8)

   ≥ 5

0/22 (0.0)

9/218 (4.1)

 Abdominal pain

15/22 (68.2)

137/205 (66.8)

0.898

 Caregiver-reported fever

10/22 (45.5)

97/217 (44.7)

0.946

 Maximal recorded temperature, °C

0.877

   < 37.0

15/22 (68.2)

172/245 (70.2)

  37.1–38.4

7/22 (31.8)

60/245 (24.5)

  38.5–38.9

0/22 (0.0)

6/245 (2.5)

   ≥ 39.0

0/22 (0.0)

7/245 (2.9)

 Duration of fever

2.4 (1.2)

2.6 (1.3)

0.605

 Decreased energy/malaise

13/21 (61.9)

147/217 (67.7)

0.586

 Excessive crying

14/22 (63.6)

96/218 (44.0)

0.079

 Admitted to hospital

3/21 (14.3)

32/223 (14.4)

1.000

 Rotavirus positive

6/23 (26.1)

104/263 (39.5)

0.203

 Status of child

1.000

  Fully recovered

10/10 (100.0)

120/133 (90.20)

  Partially recovered

0/10 (0.0)

6/133 (4.5)

  Worsening

0/10 (0.0)

1/133 (0.8)

  Recovered but became sick again

0/10 (0.0)

6/133 (4.5)