- NEW YORK (Reuters Health) - A new virus continues to
show up wherever investigators look for it -- and it isn't SARS. It's the
human metapneumovirus (hMPV), which has now been discovered in American
children.
-
- Researchers at the Yale University School of Medicine
found that 19 out of 296 New Haven, Connecticut, children who had respiratory
infections of unknown cause were infected with hMPV. Symptoms included
wheezing, cough and fever.
-
- "I think this virus probably accounts for a small
but significant portion of respiratory tract illness in children,"
study author Dr. Jeffrey S. Kahn told Reuters Health.
-
- The findings appear in the latest issue of the journal
Pediatrics.
-
- In children, 15 to 34 percent of cases of pneumonia and
a lung infection called bronchiolitis have no known cause. The most common
causes are flu viruses, parainfluenza viruses and respiratory syncytial
virus (RSV). Samples screened in the study were negative for these viruses.
-
- "If you step back and look at pneumonia in general,
about 50 percent of the time we can identify a cause," Kahn said.
"Obviously, in the other 50 percent we don't know what causes it.
So that suggests that there are unknown pathogens out there."
-
- Human metapneumovirus came to light in 2001, when researchers
in the Netherlands identified the virus in children.
-
- "When it was first reported, everybody said, 'wow,
that's very interesting,' and everybody started going back to their freezers
where they kept samples, and started to probe samples. Now it's been found
in many countries," Kahn said.
-
- In March of this year, researchers reported finding hMPV
in adults in Rochester, New York. That was the first indication that it
is circulating in the United States. It has also been found in the UK,
Canada, Australia, Japan, Finland, and France.
-
- The implications of these discoveries are not yet fully
understood. "The disease caused by this virus is really just beginning
to be explored," Kahn said.
-
- It's certain that hMPV can make people sick enough to
land them in the hospital. But Kahn said that the severity of the illness
it causes may change from year to year. More research will be needed to
find out how the virus behaves and the extent of its impact.
-
- The existence of hMPV may answer some nagging questions
for pediatricians. "We see otherwise healthy kids getting very bad
lung infections," Kahn said. It's possible that hMPV interacts with
other viruses to cause more serious infections.
-
- Before scientists determined that a new kind of coronavirus
causes SARS, or severe acute respiratory syndrome, they thought that hMPV
might play a role. Six out of eight SARS patients in Canada had both hMPV
and the coronavirus, leading researchers to wonder if one of the viruses
worsened the effects of the other. Later, they found that the coronavirus
alone causes SARS.
-
- SOURCE: Pediatrics 2003;111;1407-1410.
-
- Copyright © 2003 Reuters Limited. All rights reserved.
Republication or redistribution of Reuters content is expressly prohibited
without the prior written consent of Reuters. Reuters shall not be liable
for any errors or delays in the content, or for any actions taken in reliance
thereon.
|
