TABLE 1. Characteristics of children and adolescents aged <18 years hospitalized with laboratory-confirmed influenza and influenza and SARS-CoV-2 coinfections (N = 575) — Influenza Hospitalization Surveillance Network, United States, October 1, 2021–April 30, 2022*.
| Characteristic | No. of patients (%) with influenza and SARS-CoV-2 coinfection (n = 32) | No. of patients (%) with only influenza (n = 543) | p-value† |
|---|---|---|---|
|
Age, yrs, median (IQR)
|
3 (1–12) |
5 (2–11) |
0.27 |
|
Age group, yrs
| |||
| 0–4 |
18 (56.3) |
245 (45.1) |
0.31 |
| 5–11 |
6 (18.8) |
169 (31.1) |
|
| 12–17 |
8 (25.0) |
129 (23.8) |
|
|
Sex
| |||
| Male |
14 (43.8) |
313 (57.6) |
0.12 |
| Female |
18 (56.3) |
230 (42.4) |
|
|
Race and ethnicity
| |||
| American Indian or Alaska Native, non-Hispanic |
0 (—) |
6 (1.2) |
0.84 |
| Asian or Pacific Islander, non-Hispanic |
1 (3.3) |
23 (4.5) |
|
| Black or African American, non-Hispanic |
8 (26.7) |
149 (29.4) |
|
| Hispanic or Latino |
7 (23.3) |
139 (27.5) |
|
| White, non-Hispanic |
13 (43.3) |
183 (36.2) |
|
| Multiracial |
1 (3.3) |
6 (1.2) |
|
|
Influenza vaccination status
§
| |||
| Vaccinated |
4 (17.4) |
190 (42.4) |
0.02 |
| Not vaccinated |
19 (82.6) |
258 (57.6) |
|
| Ineligible |
5 (0.0) |
46 |
|
|
Influenza test type
¶
| |||
| Rapid antigen |
0 (—) |
8 (1.5) |
0.77 |
| RT-PCR |
32 (100.0) |
517 (95.2) |
|
| Rapid PCR |
1 (3.1) |
19 (3.5) |
|
|
Influenza type
| |||
| A |
30 (93.8) |
530 (97.6) |
<0.01 |
| B |
0 (—) |
11 (2.0) |
|
| A and B |
2 (6.3) |
2 (0.4) |
|
|
RSV test result
| |||
| Positive |
3 (10.7) |
6 (1.3) |
<0.01 |
| Negative |
25 (89.3) |
460 (98.7) |
|
|
Reason for admission
| |||
| Influenza-related illness |
26 (83.9) |
436 (81.2) |
0.68 |
| Obstetrics or labor and delivery admission |
0 (—) |
4 (0.7) |
|
| Inpatient surgery procedures |
0 (—) |
3 (0.6) |
|
| Psychiatric admission needing acute medical care |
1 (3.2) |
4 (0.7) |
|
| Trauma |
0 (—) |
10 (1.9) |
|
| Other |
4 (12.9) |
80 (14.9) |
|
|
Any underlying medical condition
|
18 (56.3) |
317 (58.4) |
0.81 |
| Chronic lung disorder |
1 (3.2) |
35 (6.8) |
0.49 |
| Chronic metabolic disorder |
4 (12.9) |
30 (5.9) |
0.10 |
| Blood disorder |
0 (—) |
35 (6.8) |
0.14 |
| Cardiovascular disorder |
2 (6.5) |
25 (4.9) |
0.67 |
| Neurologic disorder |
4 (12.9) |
88 (17.2) |
0.58 |
| Immunocompromised condition |
0 (—) |
38 (7.4) |
0.12 |
| Renal disease |
0 (—) |
9 (1.8) |
0.46 |
| Gastrointestinal or liver disease |
0 (—) |
5 (1.0) |
0.59 |
| Rheumatologic, autoimmune, or inflammatory conditions |
0 (—) |
2 (0.4) |
0.73 |
| Hypertension |
0 (—) |
7 (1.4) |
0.52 |
| Obesity |
1 (5.0) |
57 (13.8) |
0.18 |
| Pregnant** |
0 (—) |
0 (—) |
— |
|
Received influenza antiviral treatment
††
|
17 (53.1) |
326 (60.0) |
0.44 |
|
Admitted to ICU
|
10 (31.3) |
117 (21.5) |
0.20 |
|
Invasive mechanical ventilation
|
4 (12.5) |
23 (4.2) |
0.03 |
|
BiPAP or CPAP use
|
5 (15.6) |
35 (6.4) |
0.05 |
|
High flow nasal cannula
|
5 (15.6) |
57 (10.5) |
0.36 |
|
Vasopressor use
|
3 (9.4) |
20 (3.7) |
0.11 |
|
Renal replacement therapy or dialysis
|
0 (—) |
2 (0.4) |
0.73 |
| In-hospital deaths | 0 (—) | 0 (—) | — |
Abbreviations: BiPAP = bilevel positive airway pressure; CPAP = continuous positive airway pressure; ICU = intensive care unit; PCR = polymerase chain reaction; RSV = respiratory syncytial virus; RT-PCR = reverse transcription–polymerase chain reaction.
* Data on race and ethnicity were unknown for two (6.3%) patients with influenza and SARS-CoV-2 coinfection and 37 (6.8%) patients with only influenza; data on current season influenza vaccine were unknown for four (12.5%) patients with influenza and SARS-CoV-2 coinfection and 49 (9.0%) with only influenza; data on RSV test results were unknown or missing for four (12.5%) patients with influenza and SARS-CoV-2 coinfection and 77 (14.2%) patients with only influenza; and data on reason for admission were unknown or missing for one (3.1%) patient with influenza and SARS-CoV-2 coinfection and six (1.1%) patients with only influenza.
† Medians were compared using a Wilcoxon rank sum test. Proportions were compared using Pearson's chi-square tests.
§ Vaccinated is defined as immunization in a person aged ≥6 months who received ≥1 dose of the current season’s vaccine ≥14 days before positive influenza test date; a person is considered ineligible if aged <6 months.
¶ Proportions for test types are not mutually exclusive.
** Only among adolescents aged 15–17 years.
†† Influenza antiviral treatments included oseltamivir, peramivir, or zanamivir.