Sensitive Tool Implicates New Rhinovirus in Pediatric Respiratory Infections

A rapid, sensitive, and inexpensive diagnostic tool implicated a new human rhinovirus (HRV) as the cause of severe pediatric respiratory tract infections in Europe.

Scientists used the new tool, which is called MassTag polymerase chain reaction (PCR), to investigate 97 samples, collected over a three-year period, from children with hospital-admitted, acute respiratory illness where no pathogen had been identified by routine laboratory testing. HRVs were the most frequent viruses detected in the sample set, representing 75% of the identified viruses.

Human rhinoviruses are frequent causes of respiratory illness worldwide. Although they are most commonly associated with self-limited upper respiratory tract disease, lower respiratory tract infections related to HRVs are being increasingly reported in infants, elderly persons, and immunocompromised patients. HRVs are also implicated in exacerbations of asthma, chronic bronchitis, and acute bronchiolitis.

To detect pathogens, MassTag PCR uses small molecular tags to detect up to 30 different pathogens simultaneously in one test. Genetic material from a throat swab or other sample is extracted and then mixed with PCR primers--short pieces of DNA that recognize specific nucleic acid sequences within the genomes of the target viruses or bacteria. If a throat swab contains pathogens with nucleic acid sequences that match those of the primers, then the primers will copy the target DNA several million times. Likewise, the molecular tags, different in mass for each of the primers, are also amplified, making them easily detectable by mass spectrometry, a technology that identifies molecules based on their masses.

"The results of the study confirm our earlier findings in New York, namely, that these viruses represent a clinically significant but previously unappreciated species within the entero-/rhinoviruses, one of the longest known and most intensely studied virus groups,” stated Thomas Briese, Ph.D., associate professor of clinical epidemiology at Columbia University Mailman School of Public Health's Center for Infection and Immunity (New York, NY, USA) who coordinated the study. "We urgently need drugs and vaccines to address the challenges they pose to child health.”

The study appeared in the November 2007 online edition of the Journal of Infectious Diseases.


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Columbia University Mailman School of Public Health