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Parvo and Herpes, the horse or the cart???

Dr. J.P. Clewley jclewley at hgmp.mrc.ac.uk
Fri Jan 12 11:53:18 EST 1996

Sharre Smith wrote:
>>I have been following about forty people that have been diagnosed as
having cronic Parvo B19 infections. They are part of a group of over 100
recently identified in a town of 4000. Symptoms and prior diagnosis range
from encephalitis, thyroiditis, arthritis, Lupus, Chronic Fatigue, Lymes
to Wegeners Granulomatosis and the more exotic. I have noticed that many
of the people have some form of Herpes. Some have developed their first
symptom of Herpes after a positive diagnosis of Parvo, some had them
prior to the diagnosis. Cronic Parvo appears to linger for years in some
people so it is hard to be exact about what came first. My question has
to do with the relationship of helper viruses. I have read that some forms
of Parvo require a helper virus in order to replicate. Herpes and Adeno
are two of the helper virus that have been identified. Exactly how does
the relationship of the two operate? Once you have a chronic Parvo
infection, does it trigger the Herpes or vice versa. These Parvo cases
are unusual and the number is growing rapidly, few practioners have any
answers. Any and all input is appreciated.  thanks, Sharre
seasmoke at teleport.COM  Seasmoke Research  on the edge of the earth.
Yachats, Or.
Sharre Smith Public Access User -- Not affiliated with Teleport
Public Access UNIX and Internet at (503) 220-1016 (2400-28800, N81 

Your report is strange. How were the B19 diagnoses made?
Commercial serological tests may give some non-specific
reactions. Also, please distinguish between IgM and IgG
positivity. IgM indicates a recent infection; IgG a past
infectionthat has probably cleared.

By PCR B19 DNA can be detected for a few months after the
initial infection. This is not usually a chronic infection.
IMO it rperesents slow clearance of a very high level of
viraemia. Persistent B19 infection is uncommon and is
associated with an underlying immunodeficiency (inherited
or acquired) most often. Also, be aware of the possibilities
of false positives with PCR (like any PCR) and a virus
present at VERY high titres in viraemic blood.

B19 does not require a helper virus; the adeno-associated
human parvoviruses, which are non-pathogenic, do require
either an adenovirus or herpes virus as a helper.

Jon Clewley
Virus Reference Division
Central Public Health Laboratory
61 Colindale Avenue
London NW9 5HT
United Kingdom

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