In special settings, like our's contry, where parents expect that GP, or even pediatrician in secondary and tertiary care system, prescribe antibiotics for trivial acute respiratory community-aquired infections aetiology testing chan generate a critical mass of knowledge so this sort of expectation will disapear. I think that significant amount of antibiotics are still prescribed for respiratory diseases in children. Another reason could be heterogenous populations in terms of immunisation status. In Romania PCV is available but not mandatory and a minority of infants are immunised against pneumococcal disease. So parents and GP's are more prone to worst case-scenario, so they go for empirical antibiotherapy. I fully agree that in places where guidelines are fully implemented and immunisations are up-to-date virologic extensive testing can be cost-inefficient. RSV and probably RV testing [that is more difficult to perform] can have an impact on further developpment of airway [and possibly on recurrent wheezing].

Testing for viruses will surely help to avoid unnecessary use of antibiotics and thereby prevent emergence of drug resistance. Viral testing also offers new oppurtunities to learn more about clinical manifestations of various viral infections so that we are able to characterise those infections later clinically without then having to rely on virological diagnosis. Viral testing may also help to prognosticate the disease and can allay anxieties among parents and children. Unfortunately, virological tests are not widely available and even if available are not cost effective. The need of the hour is to explore ways and means of making viral testing universal and cost-effective.

I really appreciate you comments. However, isn't it enough to have evidence that this infection is (rather) viral than bacterial, e.g. by inflammation parameters (WBC, CRP, PCT, IL6....)? Why should be want to know, which kind of virus we will not treat?

And how about bacterial superinfection of viral infection - can we rely on positive virus PCR in not giving antibiotics? I am just waiting for arguments that such a multiplex PCR could really have any impact on my daily clinical work... I am still looking forward to a controversial and stimulating discussion ;-)

Virus testing in children with acute respiratory infections (ARI) is only justified for epidemiological survey or in very specific cases.

There is lot that we, clinicians (pediatricians, GP), can do in order to avoid unnecessary use of antibiotics. First of all we must remember that almost half of ARI, including pneumonia, in children aged under 2 are due to viruses. Second, when possible, chest X ray provides good evidence on etiology (although not definitive). Third, auscultation could also help. Finally, inflammation parameters (some of them available in almost any setting –i.e. WBC, neutrophills, bands) may add something.

I complete agree even in RSV patients testing might not be needed. Treatment is based on the clinical symptoms regardless of which virus the patient is dealing with

In some patients the precise nature of the virus and hence the need for PCR-testing can generate prognostic issues. I fully agree that patients should be tested for viruses if there will be an added value to inflammatory markers [and obviously to good clinical evaluation, history etc]. Such cases can be either patient-centered [like in premature infants, patients with significant commorbid lung conditions like CF, PCD or BPD], virus-centered [RSV and RV can generate significantly different subsequent risk of recurrent wheezing in an atopic child] or contextual [if there is a flu epidemic the patient would probably benefit of antivirals, in the given case of a precise diagnosis]. In many cases CRP, WBC or differential can not be helpful - I have successfuly treated (without antibiotics) several infants with adenoviral lung disease and with "horrible" inflammation. I would go for viral testing in severe cases [with a PIS (pulmonary index score) above 8] or in special patients [prematures and commorbidities].

RSV testing [rapid antigen detection tests] could be a reasonable option during fall and winter. In small and crowded units, like ours [we addmitt also premature children in our PICU+NICU] this is the feasible and cost-efficient option for nosocomial infection prophylaxis. Only really small premature infants receive Synagis prophylaxis if they have a commorbid condition that anticipates a longer lenght of stay in hospital.

Have we all forgotten how to differentiate bacteria and viral infection clinically? Bacteria are like human and will not allow body temperature to go very high. We also know some bacteria will die when the temperature goes very high. I have always used my clinical acumen for years and have never been wrong in the last three decades.

Boiling or using autoclave to sterilise syringes, needles and surgical instruments was used two decades ago and is also used in some countries even today. As doctors I hope we use the knowledge and experience to help differentiate and not depend on tests and investigations to help diagnose common infections.

We must reduce abusing antibiotics and this over-entusiastic urge to investigate, if not I am sure computers will soon replace our profession.

I think early and accurate diagnosis of influenza by rapid antigen test is essential in small children because we can avoid unneccessery antibiotic medication and hospitalizations. We can not make clinical diagnosis even in epidemic season because other respiratory viruses cause similar disease as influenza infection.

I thank you all for your very valuable contributions. My conclusion is that we will not introduce viral PCR testing as clinical routine in children with airway infections. Only, RSV testing with ELISA shall be usable in risk populations, e.g. Infants during their first winter, premature children, children with cardiac disease, mainly for hygienic reasons, I.e. to separate these from others at risk.

Only one short comment to Dr. Srivatra's comment. I disagree that we can distinguish viral from bacterial infection by the fever pattern. In bacterial infections you may find temperatures as high as in viral infections.

and, unfortunatelly, the opposite situation is also rea!. No fever doesn't rule out a bacterial infection [the case of immuno-incompetent children].

Besides RSV, influenza rapid tests should be available. Because of the urgent matter of the initiation of antivirals in this situation. Influenza, in a non-epidemic setting, can be labeled as "viral"-LRTI and the narrow terapeutic window can close, with potential devastating effects for our little patients.

In some high risk situations like, Prematurity, BPD, CHD,CF,Immunocompromised states, viral Lower respiratory tract needs to be differentiated from bacterial infection which is difficult even after taking in to consideration the epidemiogy ( age,season ) , clinical ( viral LTI preceeded by URI,fever canbe high in both infections) Investigations like CBC( neutrophilic lecucocytosis in bacterial and lymphocytic leucocytosis in viral ), CRP ( can be positive in both), Xray infiltrates ( can occur in both).Hence there is a place for multiplex PCR in managing LTI.If cost is a concern, it needs to be restricted.If cost effective , it has the potential to further appropriate antibiotic use and prevent its misuse.

Thank you all for an interesting discussion.

You need to know that bacteria are different than virus. They do not survive if the temperature goes high and so will release enzymes that will suddenly reduce temperature. I have worked all my life in hospitals and have used this criteria t start antibiotics and have never failed. Doctors like you have criticised because they too did not use the common sense. Two days later they apologised because the blood culture I had taken before starting antibiotics were positive.

I agree with Dr. Schneider. In otherwise healthy children, with mild respiratory disease (most of them), no further etiological investigation are necessary (except for epidemiological issues).

Dr Schneider is right. Rapid diagnosis of RSV at the beginning of the season is valuable as children could be cohorted and manage in ward bays when the number of beds/cots are limited.

Identification of other viral causes of respiratory infection are only useful for surveillance and epidemiological purposes.

I agree that bacteria causes of respiratory tract infection could easily be differentiated from viral infections in most cases in well nourished children. This may not be the case in some parts of the world where there are other causes of febrile illnesses in younger children, such as malaria fever, enteric fever and high incidence of malnutrition.

Investigating for viral infections is practically not possible in our country due to high cost of investigations, and it will not help in terms of self limiting viral infections

Actually patients with simple upper respiratory tract infections will not get benifit from such study.

in more severe cases we need to test to help us in patients placement and type of isolation precaution needed. and we need these test as well for research purpose but not as a rotein,

There are two issues worth mentioning in addition to those given. Firstly having a positive viral identification may have prognostic value - rhinovirus in a wheezy infant makes asthma more likely (either as a marker or as a potentiator), adenovirus of certain types may be associated with devastating infection, enteroviruses may cause other complications. Knowing it is "just RSV" or "just parainfluenza" can be very helpful. Secondly, parents get "it's just a virus" all the time, so much that it sounds like a mantra to pass off their concerns. If you can tell them you have identified a specific virus it actually makes a big difference to your credibility, and their confidence and assurance that that is what is going on. They are not as likely to go searching for a doctor who will prescribe a cure. Simultaneously it helps their medical understanding - if they know their child, or others, have real influenza and what that is like, as opposed to what is popularly called "the flu" (the common cold) it makes a difference to their perception of the vaccine.

I admit, however, that having the test available is a luxury, and is rarely going to save lives directly.