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Recently Discovered Virus Associated With
Pediatric Respiratory Tract Infection In Germany
The research team used MassTag PCR to investigate
97 samples, collected over a three-year period, from
children with hospital-admitted, acute respiratory
illness wherein no pathogen was identified through
routine laboratory testing. Human rhinoviruses 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 HRV are being increasingly reported in infants,
elderly persons, and immunocompromised patients. HRVs
are also implicated in exacerbations of asthma, chronic
bronchitis, and acute bronchiolitis.
"Acute respiratory infection is a significant
cause of morbidity and mortality in children worldwide.
Accurate identification of causative agents is critical
to case management and to prioritization in vaccine
development," stated W. Ian Lipkin, MD, professor
of Epidemiology, Neurology, and Pathology at Columbia
University, director of the Center for Infection and
Immunity at the Mailman School of Public Health, and
senior author of the paper.
In up to 50% of cases of severe respiratory disease,
a causative agent is not identified, despite the application
of PCR assays as well as classical diagnostic methods
including culture, antigen tests, and serology. Broad-range
molecular systems pioneered by this team including
MassTag PCR, GreeneChips and high throughput metagenomic
sequencing, enable pathogen discovery, surveillance
and medical diagnostics. Recent application of these
technologies led to diagnosis of viral hemorrhagic
fevers in Africa, a new virus causing transplant deaths,
and detection of Israel Acute Paralysis Virus in honey
bees with Colony Collapse Disorder.
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, PhD, associate professor of clinical
Epidemiology, who coordinated the study. "We urgently
need drugs and vaccines to address the challenges they
pose to child health."
In an editorial commentary in the December 15 issue
of the Journal of Infectious Diseases, Anne Moscona,
MD, departments of Pediatrics and of Microbiology and
Immunology, Weill Medical College of Cornell University,
states that the work of Dr. Lipkin's team with MassTag
PCR, "provides a paradigm for new detection strategies
for early recognition and containment of a wide range
of respiratory pathogens." |