Results
A total of 3699 patients had RPA sent within 48 hours of hospital
admission in the study period (01/01/15 – 12/31/19). Among these
patients, 2192 had a positive RPA and were included in the study. One
thousand eight hundred thirty-one patients had only a single virus
detected (Group A), while 361 had more than one virus detected (group
B). Thirty-seven patients had three or more virus detected, four
patients had four or more virus detected, and one patient had six
viruses detected in the RPA.
A total of 2595 viruses were identified in the RPA of the included
patients (including all the coinfections). Rhino enterovirus comprised
almost half of all the viruses identified (n=1278, 49.2%). Proportion
of other viruses included respiratory syncytial virus (n=422, 16.2%),
parainfluenza virus (n=222, 8.5%), metapneumovirus (n=140, 5.3%),
influenza virus (n=151, 5.8%), coronavirus (n=193, 7.4%), adenovirus
(n=189, 7.2%). Among the patient with two virus coinfections, the most
common combination was Rhino/enterovirus and respiratory syncytial virus
(22.4%). The other common combinations were Rhino/enterovirus and
adenovirus (17.4%), Rhino/enterovirus and parainfluenza virus (13.8%)
and Rhino/enterovirus and coronavirus (8%). (Table 1)
The median age of the study population was 15.9 months (IQR 3.8, 43.8).
Patients who had coinfection were significantly younger (11.3 [IQR
4.3, 25.1]) than patients hospitalized with single virus infection
(17.0 [IQR 3.7, 48.8]), p= 0.001. There was a higher proportion of
infants (50.9%) among patients who had coinfection, as compared to
patients with single viral infection (41.3%), p <0.001. There
was no difference in gender distribution or racial distribution in the
two groups. Children with coinfection had an overall lower median
weight; however, there was no significant difference in the body mass
index or percentage of obese patients in the two groups. Overall
positive urine culture was detected in 8.2% of total patients at the
time of admission, while positive blood and respiratory culture were
detected in 2.0% and 2.5%, respectively. A much higher proportion of
patients with coinfection had a positive respiratory culture within 24
hours of hospital admission (4.7%) as compared to only 2.1% in
patients with a single viral infection, p= 0.004. There was no
significant difference in the patients who had positive blood culture or
positive urine culture at the time of admission. Asthma was the most
prevalent comorbidity and was present in 463 (21.1%) of the total
patients. There was, however, no significant difference in the diagnosis
of asthma between the two groups. Similarly, the two groups were similar
in terms of the proportion of patients who were premature, had
congenital heart disease, or had a pre-existing diagnosis of
developmental delay. There was, however, a higher proportion of patients
with single viral infection (4.0%) who had an oncologic diagnosis as
compared to patients with coinfection and had an oncologic diagnosis
(1.6%), p= 0.02. (Table No 2)
Overall, oral antibiotics were prescribed to 155 patients in the study
population (7.0%), and intravenous antibiotics were prescribed to 646
patients (29.4%) within six hours of hospital admission. There was no
difference in the proportion of patients who were prescribed oral or
intravenous antibiotics among the two groups. The median intravenous
antibiotic duration in the study population was one day (IQR 0, 2), and
24 patients (1%) received antibiotics that were prescribed at the time
of admission, for five or more days. There was no difference between the
two groups in terms of antibiotic duration. 60.7% of the patients
received a chest x-ray (CXR) during the hospitalization. A higher
proportion of patients with coinfection (66.4%) received CXR compared
to patients with single virus infection (59.5%), p= 0.01. There was no
difference in the number of chest x-rays performed during
hospitalization in the two groups. Overall, 8.1% of the study
population had a Pediatric Emergency Response Team (PERT) activation
during the hospitalization, and this proportion was higher in patients
with coinfection (11.6%) as compared to patients with single viral
infection (7.4%), p= 0.007. Only six patients out of all included
patients had “code blue” (cardiac arrest) during their
hospitalization, and there was no difference in the two groups. The
median cost of care for hospitalization of patients with viral -related
illnesses was $ 2468.59 (IQR $ 1452.27, $ 4754.90). There was a
significant difference in the two groups with a higher median cost of
care ($ 2934.89) in patients with co-viral infections compared to
patients with single viral infection ($ 2381.14), p= 0.002. (Table No
3). The difference in cost of care however did not persist on multi
variable linear regression after accounting for confounders (parameter
estimate 1.1104 coinfection versus single infection, P value 0.052)
(data not shown)
Overall, 41.1% of the patients required intermediate level admission in
the hospital, and 23.4% required ICU admission. There was no
significant difference in the proportion of patients requiring
intermediate or ICU admission among the two groups. Among the patient
who required ICU admission, the median length of stay was 1.9 days (IQR
0.91, 4.76). There was no significant difference in the ICU length of
stay between the two groups. A significantly higher proportion of
patients with coinfection required initiation of high flow cannula
(145/361, 40.1%) compared to patients with single viral infection
(28.0%), p <0.001. This difference remained significant on
multi variable logistic regression after accounting for confounders
(p<0.001, data not shown). Similarly, a higher proportion of
patients with coinfection (8.2%) required intubation compared to
patients with single viral infection (5.6%); this difference, however,
was not statistically significant, p= 0.07. The overall median duration
of intubation for patients who required intubation was six days (IQR 2,
9). This was comparable in the two groups. The median hospital length of
stay for the study population was two days (IQR 1, 4), and patients with
coinfection stayed in the hospital for a significantly longer duration
(3[IQR 1, 5] vs. 2 [IQR 1, 4], p= 0.0003). A total of seven
patients died during hospitalization, with an overall mortality rate of
0.3%. There was no difference in mortality between the two groups.
(Table No 4). The difference in hospital length of stay in the two
groups were significant on multi variable linear regression with a
parameter estimate of 1.116 for coinfection versus single infection,
p=0.01 (data not shown).