A list of all communicable viruses that can lay dormant in a human
being and that individual would not know they have the
virus/disease/illness without a certain event (coughing, skin contact,
body fluid exchange, etc.) happening to trigger the virus
and thus giving it to another person?

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Request for Question Clarification by missy-ga on 18 Sep 2002 14:46 PDT

Hi there,

In the realm of infectious diseases, "dormant" usually means
"inactive".  It can be passed to another person and still remain
"dormant".  Events do trigger reactivation of the disease, but such
events do not include coughing, etc.  Those are merely means of
transmission.

Take Epstein-Barr virus, the virus that causes infectious
mononucleosis, for instance:

"Although the symptoms of infectious mononucleosis usually resolve in
1 or 2 months, EBV remains dormant or latent in a few cells in the
throat and blood for the rest of the person's life. Periodically, the
virus can reactivate and is commonly found in the saliva of infected
persons. This reactivation usually occurs without symptoms of
illness."

[...]

"Persons with infectious mononucleosis may be able to spread the
infection to others for a period of weeks. However, no special
precautions or isolation procedures are recommended, since the virus
is also found frequently in the saliva of healthy people. In fact,
many healthy people can carry and spread the virus intermittently for
life. These people are usually the primary reservoir for
person-to-person transmission. For this reason, transmission of the
virus is almost impossible to prevent."

Communicable disease avoidance for Lifeguards
http://members.tripod.com/waterrescuer/safety/_communicable_disease_avoidance_for_lifeguards.htm

In the case of EBV, it is entirely possible for a healthy person to
transmit the virus to another party.  That party may or may not then
develop symptoms.

Is it strictly this the sort of communicable disease you had in mind,
or are you also interested in diseases which can be transmitted during
their incubation time (while the sufferer is still symptomless and is
unaware of the infection)?

--Missy

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Clarification of Question by 9389-ga on 19 Sep 2002 07:54 PDT

Thank you for following up on my question.  Also diseases which can be
transmitted during their incubation time (while the sufferer is still
symptomless and is unaware of the infection), too.  In actuality I was
needing examples of both.

Thanks for the chance to clarify my question.

---

Clarification of Question by 9389-ga on 19 Sep 2002 07:58 PDT

Did you receive my clarification?

Hi there!

There are a number of communicable diseases which can be transmitted
from person to person while dormant (inactive or latent).  In
particular, the class of viruses known as the herpesvirus family are
known to be transmissable during dormancy, then can "activate" when
certain conditions are met - exposure to sunlight, the host being
otherwise immunocompromised (battling another infection, in a state of
general fatigue), or the host being under stress.  A carrier can
spread the virus without ever being aware of being a carrier, and
without exhibiting any symptoms him/herself.

Others have no dormancy period, but can be passed from person to
person before they are aware of their infection - either during
incubation, or immediately following, but prior to manifestation of
symptoms.  Like those with dormancy periods, these can be spread
without the carrier being aware of an infection.

I've compiled a listing of both of these kinds by reading the
Infectious Diseases fact sheets available at the Centers for Disease
Control, and sorting them into the appropriate categories.

A note about the answer:  Typically, when referencing web pages, we
quote relevant passages from the pages to go with each link.  Due to
the sheer number of viruses listed, I've opted *not* to quote from the
pages - you'd be sifting through for days just to get your list! 
Instead, I've opted not to quote, in order to give you a more "eyeball
friendly" list, and have included links which  explain each virus. 
I've broken the list into two categories - those which are
transmissible during dormancy (latency) and those which are
transmissible during incubation or prior to onset of symptoms.

If you wish to have quotations to match up with each virus, just ask,
and I will gladly compile those for you as well.

(The New York State Department of Health Communicable Disease Fact
Sheet offers information about many communicable diseases.  Where
available, I will include a link for each viral infection noted, which
describes the infection in detail.  Other links will be from the
Centers for Disease Control, ViraCor Biotechnologies, and other
available reference sources.)

Examples of communicable viruses which can be spread during dormancy -
absence of active infection (or reactivate after prolonged dormancy)
are:

Chickenpox (varicella zoster)
http://www.health.state.ny.us/nysdoh/consumer/chickenp.htm

(Varicella does not spread during dormancy.  It may, however,
reactivate years later as shingles
(http://www.health.state.ny.us/nysdoh/consumer/shingles.htm))

Cytomegalovirus
http://www.health.state.ny.us/nysdoh/consumer/cytomega.htm

Herpes I (causes cold sores)
http://www.cdc.gov/ncidod/hip/abc/facts06.htm

Herpes II (genital herpes)
http://www.health.state.ny.us/nysdoh/consumer/herp.htm

Infectious Mononucleosis (Epstein-Barr virus)
http://www.health.state.ny.us/nysdoh/consumer/infect.htm

Roseola (HHV-6)
http://www.viracor.com/questions.html#C1

Venereal Warts
http://www.health.state.ny.us/nysdoh/consumer/vener.htm

Examples of viruses which can be transmitted during the incubation
period or before symptoms manifest and the infected person is aware of
the infection include:

Fifth Disease
http://www.health.state.ny.us/nysdoh/consumer/fifth.htm

Hepatitis A
http://www.health.state.ny.us/nysdoh/consumer/hepat.htm

Hepatitis B
http://www.health.state.ny.us/nysdoh/consumer/hep_b.htm

Hepatitis C
http://www.health.state.ny.us/nysdoh/consumer/hep_c.htm

Human Immunodeficiency Virus (The CDC offers a dozen detailed fact
sheets)
http://www.cdc.gov/hiv/general.htm

Influenza  (*contagious on last day of incubation, before symptoms
appear)
http://www.health.state.ny.us/nysdoh/consumer/influ.htm

Measles (Rubeola)
http://www.health.state.ny.us/nysdoh/consumer/measles.htm

Mumps
http://www.health.state.ny.us/nysdoh/consumer/mumps.htm

Non-Polio Enterovirus
--23 Coxsackie A viruses
--6 Coxsackie B viruses
--28 echoviruses
--4 other enteroviruses
http://www.cdc.gov/ncidod/dvrd/revb/enterovirus/non-polio_entero.htm

Poliomyelitis
http://www.health.state.ny.us/nysdoh/consumer/polio.htm

Rubella
http://www.health.state.ny.us/nysdoh/consumer/rubella.htm

Viral Gastroenteritis
--Adenoviruses
--Astroviruses
--Norwalk virus
--Rotavirus (sometimes nicknamed Roto-Rooter, as it causes severe
diarrhea)
http://www.cdc.gov/ncidod/dvrd/revb/gastro/faq.htm


Viral Meningitis
http://www.health.state.ny.us/nysdoh/consumer/viral.htm

...and, not to forget, the "common cold", which is actually caused by
a number of viruses.

This is, of course, a listing of infectious diseases relating only to
the criteria you've mentioned (transmissible during dormancy (latency)
or during incubation or prior to onset of symptoms).  For some
informative (if a bit unsettling) reading about the many diseases that
we can pick up, including bacterial infections and mosquito and
foodborne illnesses, the Centers For Disease Control offer a library
full of information:

Infectious Disease Information A - Z
http://www.cdc.gov/ncidod/diseases/index.htm

I hope this is the information you were seeking.  If I can be of
further assistance, or you need clarification of anything above,
please don't hesitate to ask.  I'll be glad to help.

--Missy

My search strategy included:  Google queries: [ "communicable disease"
dormant latent ], [ "virus transmission" ], page by page reading of
The New York State Department of Health Communicable Disease Fact
Sheet, page by page reading at the CDC website, some source reading
through PubMed ( http://www.pubmed.com ), conversations with a friend
at the University of Michigan Medical School, and a kind "directional
pointer" from fellow Researcher tehuti-ga, who has my thanks for her
help.

Question answered to extent I needed and in a fairly timely manner.  Thanks.