ABSTRACT
The conventionnal tools used for virological diagnosis include direct antigen detection by immunofluorescence (IFA) or an immunoenzymatic test (EIA), and viral isolation technique (VIT). In most cases, IFA and EIA have a slightly lower sensitivity than VIT but are also able to detect some VIT-negative samples. Results of several teams using RT-PCR technologies show that the molecular methods detect more positive cases than the conventional tools. Work is under way to expand the number of viruses detected by multiplex RT-PCR and to determine wether newly discovered viruses, such as human metapneumovirus, contribute to burden of paediatric lower respiratory infections. In conclusion, according to requirements of speed, low cost of the methods, and to achieve the highest rate of detection of respiratory viruses, the combined use of IFA and multiplex RT-PCR is today likely to be the best way to improve diagnosis of respiratory illnesses in children.
