New Human Coronavirus
Identified, Named HCoV-NL63

From Patricia Doyle, PhD

From ProMED-mail
New Human Coronavirus Identified
Australian Broadcasting Corporation 3-26-4
Dutch scientists have announced they had identified a previously unknown coronavirus that causes respiratory disease and is likely to have spread around the world. The virus is only the 4th coronavirus to be found in nearly 4 decades and could explain many cases of respiratory illness that leave doctors baffled. Named HCoV-NL63, the virus causes symptoms similar to a bad cold and does not unleash the pneumonia characterised by severe acute respiratory syndrome (SARS) coronavirus, which killed some 800 people and infected 8000 in the 2002-03 epidemic. Young children and people whose immune system has been compromised by HIV or other diseases are more at risk although not apparently fatally so.
In a study published online by the journal Nature Medicine [see reference below], the University of Amsterdam team report on their detective work, launched after a 7-month-old girl was to admitted to their hospital in April 2003 with bronchiolitis, an inflammation of the lower airways. Tests for common cold viruses, influenza virus, and other well-known [respiratory] viruses all proved negative.
"At first, we were worried that the child may have caught the virus from an animal because she had been to the zoo the previous weekend," said the research supervisor, Ben Berkhout, an expert in human retrovirology. [Then using RT-PCR screening the Dutch team obtained a couple of fragments that looked like coronavirus genome fragments but not identical to one of the known human coronaviruses]. Closer examination of its genetic code showed it shares about 2/3 of its nucleotides with the 3 established coronavirus human coronaviruses. In other words, it was an independent member of the coronavirus family that had never been spotted before.
The team then tested stored samples taken from other admissions and found that another 7 patients with respiratory problems -- 7 percent of admissions -- had been infected by the same virus. 4 of the 7 were children less than 12 months old and 3 were adults. 2 of the adults had an impaired immune system -- one had had a bone-marrow transplant and the other had AIDS.
These findings suggested that: "This novel coronavirus is already widespread in the population," said Lia van der Hoek. "It is causing perhaps the symptoms of common colds, but in the younger individuals it is causing more severe respiratory problems," Mr Berkhout said. "About 20 to 50 percent of respiratory problems do not have a [known] viral cause, so we now can fill in a significant fraction of those unknowns." Dr Berkhout admitted it was "surprising" that this virus had never been found before, but part of the problem was the lack of tools to detect new agents easily. In general, coronaviruses are usually transmitted by airborne droplets breathed in from someone in proximity who, for instance, sneezes or coughs.
[The paper referred to in this report is published in the current online edition of Nature Medicine: "Identification of a new human coronavirus, by Lia van der Hoek, Krzysztof Pyrc, Maarten F Jebbink, Wilma Vermeulen-Oost, Ron J M Berkhout, Katja C Wolthers, Pauline M E Wertheim-van Dillen, Jos Kaandorp, Joke Spaargaren, Ben Berkhout University of Amsterdam."
The unexpected identification by virologists in Amsterdam of a novel human coronavirus predominantly associated with relatively mild upper respiratory tract disease and more specific lower respiratory tract disease (bronchiolitis) in infants comes not long after the equally surprising identification of another novel global human respiratory pathogen (human metapneumovirus) by virologists in Rotterdam, and is another remarkable "first" for Dutch virologists. The new coronavirus has been designated HCoV-NL63 and is clearly different from the 3 known human coronavirus species -- _Human coronavirus 229E_, _Humman coronavirus OC43_, and the _SARS coronavirus_. These human coronaviruses (together with other mammalian coronaviruses) belong to 3 phylogenetically distinct clusters of species within the genus _Coronavirus_ of the family _Coronaviridae_. The precise evolutionary relationship of this new human coronavirus to the established members of the family has yet to be determined. - Mod.CP]
Paramyxoviruses, new human pathogen - Netherlands 20010603.1094 .....................mpp/cp/pg/mpp
Patricia A. Doyle, PhD Please visit my "Emerging Diseases" message board at: Zhan le Devlesa tai sastimasa Go with God and in Good Health



This Site Served by TheHostPros