Table II.
Respiratory Virus Frequencies Over a 2‐year Period as Identified by Routine Antigen Detection Assays and PCR in Patients < 5 years of Age
| Viruses detected by IFA assays (patients <5 years) (total: 1,637) | Viruses detected by PCR assays (patients <5 years) (total: 610) | Frequencies (patients <5 years) | IFA co‐infection frequency | PCR co‐infection frequency | Healthy patient group (n = 46) | |
|---|---|---|---|---|---|---|
| RSV | 353 | 57 | 30.1%a | 5.3% | 51.1% | 2 (4.2%) |
| PIV‐1 | 11 | 2 | 1.0%a | 18.2% | 66.6% | 0 |
| PIV‐2 | 8 | 5 | 1.2%a | 25.0% | 16.7% | 0 |
| PIV‐3 | 88 | 16 | 7.8%a | 16.7% | 37.5% | 0 |
| Influenza A | 38 | 7 | 3.4%a | 12.2% | 61.1% | 0 |
| Influenza B | 6 | 8 | 1.6%a | 33.3% | 30.0% | 0 |
| Adv | 39 | 22 | 5.7%a | 24.4% | 74.1% | 1 (2.1%) |
| CMV | 5 | Not tested | 0.3%a | 0.0% | Not tested | Not tested |
| Total tested | ||||||
| hMPV | N/A | 29 | 4.8% | N/A | 68.9% | 0 |
| hBoV | N/A | 37 | 6.1% | N/A | 74.3% | 2 (4.2%) |
| hCoV‐NL63 | N/A | 13 | 2.1% | N/A | 92.3% | 0 |
| hCoV‐OC43 | N/A | 11 | 1.8% | N/A | 75.0% | 0 |
| hCoV‐229E | N/A | 2 | 0.3% | N/A | 50.0% | 0 |
| hCoV‐HKU1 | N/A | 1 | 0.2% | N/A | 100.0% | 0 |
| Rhinovirus | N/A | 201 | 33.0% | N/A | 46.6% | 9 (18.8%) |
| WUb | N/A | 21 | 6.8% | N/A | 68.2% | 0 |
| KIb | N/A | 3 | 1.0% | N/A | 100.0% | 0 |
The prevalence of each of the conventional viruses in the complete specimen group was adjusted to take into account the reduced sensitivity of the IFA relative to the complete specimen group since RT‐PCR was used to screen mainly specimens that already tested negative by IFA: (% IFA positive in total group) + (% RT‐PCR positive in negative specimen group). This was equivalent to extrapolation values calculated as follow: Conventional respiratory viruses = ((Respective virus percentage identified by RT‐PCR in IFA‐negative sample group × total IFA‐negative samples) + number of virus present in IFA‐positive group) ÷ total number of specimens in the study group.
Data from Venter et al., 2009.