Best Evidence Topics
  • Send this BET as an Email
  • Make a Comment on this BET

Rapid Influenza Testing Of Febrile children in the Emergency Department

Three Part Question

In [febrile children presenting to the ED] does [rapid testing of Influenza virus] alter [subsequent management]?

Clinical Scenario

A baby is brought in to ED, by concerned parents, with high fever and history of generally being unwell with no clear history pointing towards any clear diagnosis or focus of infection. You wonder whether you need to proceed with a full septic screen, or whether a positive diagnosis of influenza on rapid bedside testing would be sufficient to allow safe discharge directly from the ED.

Search Strategy

PubMed, with the full 3 part question in addition to search on Cochrane and google.
((children) AND (emergency department)) AND (rapid influenza testing) AND ((Humans[Mesh]) AND ((infant[MeSH] OR child[MeSH] OR adolescent[MeSH])) ) Limited to english literature only

Search Outcome

11 articles in total were found, remaining 6 studies were selected, one was a simple review from 2005 but with no systematic/meta-analysis and thus was dropped, 2 articles were dropped, one for age consideration (study included patients up to age of 21 years), another for being incomplete (with pending results) and two others were found to be irrelevant to the clinical question on more detailed inspection. The seven remaining studies were selected for appraisal

Relevant Paper(s)

Author, date and country Patient group Study type (level of evidence) Outcomes Key results Study Weaknesses
Noyola et al,
1530 pts, age 1-19 y during two consecutive confirmed influenza seasons at an urban children’s hospitalRetrospective case control study. RIT used to detect influenza A virus. RIT +ve as case control group and -ve as control group. Blood cultures used to confirm the resultsAntibiotic prescription,. Duration of antibiotic treatmentIn admitted pts: RIT +ve 43% vs 64% RIT -ve. p-0.04 Discharged pts RIT +ve 20% vs 53% RIT -ve p=0.04. RIT +ve 3.5 vs 5.4 days -ve p=0.03Retrospective study

Relied on electronic database for identifying pts who had RIT, then their medical records, so possible selection bias. Underlying diseases and their severity influencing the investigations not explained.

Bonner et al,
391 pts 2 month to 21 years during one confirmed influenza season at tertiary care urban hospital. Data/results for the sub group of 241 pts aged 2-36 months analysed and available as well. Prospective Randomised Control Trial. One group, for which physicians were aware (PA) of RIT results and the other group for which they were unaware (PUA) of results for influenza A and B CBC requestingPA 0% vs 13% PUA (p<0.001)Single influenza season results. Results not confirmed by blood cultures
Blood culturesPA 0% vs 11% PUA (p<0.001)
CXRPA 7% vs 26% PUA (p=001)
Financial costs of investigationsPA $15 vs $92 PUA (p<0.001)
Antibiotic usagePA 7% vs 26% PUA (p<0.001)
Length of emergency department stayPA 25 vs 49 min PUA (p<0.001)
Benito-Fernández et al,
206 pts aged 0-36 months during two confirmed seasons at a tertiary care children’s hospitalProspective observational study. RIT (influenza A & B) for all febrile pts, grouped by results into RIT +ve and RIT eve groups (all pts <3 months old had RIT whether febrile or notBlood tests (CBC, CRP, blood cultures)RIT +ve 33% vs 100% RIT -ve (p <0.01)No randomisation. No follow up of -ve RIT patients (presumably no follow up of the positives either). No confirmatory tests by viral culture done.
Urine analysisRIT +ve 80% vs 100% RIT -ve (p <0.01)
Lumbar punctureRIT +ve 1.3% vs 21% RIT -ve (p<0.01)
CXRRIT +ve 14% vs 32% RIT -ve (p <0.01)
Emergency department stayRIT +ve 116 vs 192 min RIT -ve (p<0.01)
Observation ward admissionRIT +ve 8.3% vs 21% RIT-ve (p<0.01)
In-patient admissionRIT +ve 2.3% vs 16.4% RIT -ve (p<0.01)
Antibiotic treatmentRIT +ve 0% vs 38% RIT -ve (p<0.01)
Poehling et al,
486 pts < 5 years during two consecutive influenza seasons at a university hospital paediatric emergency departmentProspective Randomised Control Trial. TG underwent RIT with results available to the clinician. CG had no RIT. Both groups had formal viral cultures or PCR lab testing for influenza.Any diagnostic test doneTG 39% vs 52% CT p=0.03No follow up. Convenience sample.
CXRTG 23% vs 33% CT p=0.06
Blood count/culturesTG 10% vs 18% CT p=0.05
Iyer et al,
700 pts 2-24 months during 2 influenza seasons at an urban tertiary care hospital Prospective Quasi- Randomised Control Trial Intervention group (POCT) underwent RIT for influenza with available results. CG (ST): no RIT results availableBlood cultures Reduction in POCT by 22.6% p=0.05Convenience sample. Pneumococcus immunisation status & its effects on pts not considered. No follow-up
Urine analysisOR 0.45 vs 0.67 p=0.002
Urine cultureOR 0.46 vs 0.67 p=0.005
Abanses et al,
1007 patients aged 3-36 months during one influenza season at an urban children's hospital emergency departmentProspective randomized controlled trial. Febrile patients were randomised at triage into an intervention group (TT) having RIT for influenza A and B with available results or a non-intervention group (SP) for which the physician decided the need for further testing. RSV testingTT 7% vs 18% SP (RR 2.5)Failure of randomisation in TT group due to their non-adherence to their devised protocol so taken as convenience sample. Single influenza season results.
CXRTT 20% vs 26% SP (RR 1.3)
CBCTT 2.5% vs 29% SP (RR 12)
Blood culturesTT 2.5% vs 31% SP (RR 5.7)
Urine analysisTT 4.9% vs 28% SP (RR 9.2)
Emergency department length of stayTT 156 vs 195 min SP
Total medical cost per patientTT $393 vs $666 SP
Sharma et al,
72 patients aged 2-24 months during two consecutive influenza seasons at an urban children's hospital emergency department.Retrospective observational study. Influenza A virus detection by RIT in two groups: those who had RIT results available (early detection; ED) and those who had diagnosis after discharge (late detection; LD).Ceftriaxone useED 2% vs 24% LD p=0.006Selection bias. Small sample size. Retrospective study relying on electronic database, so some patients could be missed if difference in tests and conditions.

Physician's discretion to do RIT.
CBC performedED 17% vs 44% LD p=0.02
Urine analysis performedED 2% vs 24% LD p=0.006


Good evidence (level 1b) is available, confirming that rapid influenza testing, when used appropriately, can be a reliable tool in assessment of febrile children attending Emergency Department and improves efficiency. However, there appears to still be some reluctance to develop any standardised protocol using rapid influenza testing in routine assessment of febrile children.

Editor Comment

CBC, complete blood count; CG, control group; CRP, C-reactive protein; pts, patients; RCT, randomised controlled trial; RIT, rapid influenza testing; RSV, respiratory syncytial virus; TG, test group.

Clinical Bottom Line

Rapid Influenza testing can have a significant impact on management of febrile children in the ED, especially at times of high influenza prevalence


  1. Noyola DE, Demmler GJ. Effect of rapid diagnosis on management of influenza A infections. Pediatr Infect Dis J. 2000 Apr;19(4):303-7.
  2. Bonner AB, Monroe KW, Talley LI et al. Impact of the rapid diagnosis of influenza on physician decision-making and patient management in the pediatric emergency department: results of a randomized, prospective, controlled trial. Pediatrics 2003 Aug;112(2):363-7.
  3. Benito-Fernández, Javier, Vázquez-Ronco, Miguel A, Morteruel-Aizkuren, Elvira et al. Impact of Rapid Viral Testing for Influenza A and B Viruses on Management of Febrile Infants Without Signs of Focal Infection. Paed Inf Dis J 2006; 25(12):1153-1157.
  4. Poehling KA, Zhu Y, Tang YW et al. Accuracy and impact of a point-of-care rapid influenza test in young children with respiratory illnesses. Arch Pediatr Adolesc Med 2006 Jul;160(7):713-8.
  5. Iyer SB, Gerber MA, Pomerantz WJ et al. Effect of Point-of-care Influenza Testing on Management of Febrile Children Acad Emerg Med 2006; 13(12): 1259-1268.
  6. Abanses JC, Dowd MD, Simon SD, et al. Impact of rapid influenza testing at triage on management of febrile infants and young children. Pediatr Emerg Care 2006;22:145-9.
  7. Sharma V, Dowd MD, Slaughter AJ, et al. Effect of rapid diagnosis of influenza virus type a on the emergency department management of febrile infants and toddlers. Arch Pediatr Adolesc Med 2002;156:41-3.