[Parasitology] On the Possible Differences between the terms 'Infection' and 'Infestation'

Don Daniels via parasite%40net.bio.net (by yssmlp from hotmail.com)
Fri Aug 3 11:25:39 EST 2007

(from http://www.geocities.com/yssmlp/ii.htm )

On the [Possible] Difference(s) in the Definition and the Usage of the terms 
'Infections' and 'Infestations'

On the [Possible] Difference(s) in the Definition and the Usage of the terms
'Infections' and 'Infestations' - short notes by YSS 1989-, - study material

This reference text belongs to my personal notes, but it can be used and
distributed freely to anyone without conditions, in part or complete.
All the arguments have been weighed several times.


The terms "Infection" and "Infestation" often appear to be used as synonyms
both in the Literature and in practice.  Furthermore, in many cases I've
observed as evident an apparent state of confusion regarding their usage,
even among Professionals.  However, in practice I've also observed that the
term  "Infestation" seems to be reserved/preferred for "swarms of 
multicellular organisms [AND unicellular organisms not bacteria or fungi] 
crowd a host", whereas the term "Infection" seems to be used both for the 
rest of
the cases [bacteria, fungi and others] and also where organisms that are
considered 'to infest' are found.

Despite this, according to my observations and study of the terms, the
difference between one and the other may not be subtle after all, perhaps
at least from a particular perspective. A careful examination of the words

First of all, let's consider the following simple proposition:

"The term "Infestation" seems to suggest an ACTION.
The term "Infection"   seems to suggest  a CONDITION, a STATE."

By definition, an "Infestation" is an ACTION.  It is an action where someone 
something is overrun in great numbers by something else[1].  An "Infection", 
turn, is or seems to be more like a CONDITION, a STATE, where someone or
something is tainted, spoiled, ruined or wasted by or due to something[2].

Ergo, in this sense the terms are NOT or don't seem to be synonyms.

[ ** If I remember it well, "Infestation" comes from the Latin word  
[infestus - "hostile, unsafe"], which in time came to mean something like 
annoy, to trouble, to disturb, to attack, to invade, to overrun" , but which
long ago used to mean inexorable [or unyielding/relentless - from "in" [NOT]
"festus" [(something that can be) seized]] [*].

"Infection", on the contrary, comes from the Latin word 'infectio' 
- to corrupt, to spoil, to stain] [*].]


Because of these facts and as a result, I use the words according to the 
that derives from my personal understanding of them added to my [ever so
limited] experience.

For example:

An organism is Infected when it's AFFLICTED Pathologically, that is, when 
is a Pathological Manifestation or Presentation of Corruption, Contamination 
Taint in it, evident at an instant [evident as a STATE of degradation].  
Infested if it's SWARMED by bodies that are tending to or are overrunning it
at some undetermined point in time, whether or not such action occurs along
an "obvious" Pathological Manifestation.

[What is an "obvious" Pathological Manifestation?  An "imminent", 
Acute one, perhaps? Do Bacteria Infest?  Do Infestations BECOME Infections?
Do they precede them?]

If I find an organism overrun by Larvae of any sort, immediately I think 
Infested".  If I see decay [signs of an infection], I think "It's Infected"
["It's Corrupted"].

If I see no signs of Infection in the host organism and it's Infested, I 
tend to
think "Infested, no visible signs of Infection.. Must examine deeper".


'Closing' and lingering questions and thoughts:

Are Infestations the Preliminary Condition of Infections?
Are Infestations a Necessary Condition for Infections?
Are Infections the logical consequence of Infestations?

An Infestation can present Corruption [the sign of an Infection], but 
it doesn't seem to [at least not in an 'obvious' fashion or 'not at first' 
not for some period of time].  If it does, could such Infestation be defined 
the Possible Underlying [Primary] Cause for the condition when and if it 

An Infection, in turn, ALWAYS presents Corruption 
in one form or the other.

Infections/Infestations seem to present interactions that in my opinion
are being underestimated enormously.

Because Infections/Infestations seem to interact, very often they would tend 
coexist in the host, [maybe] sometimes dependently, [maybe] sometimes
independently, but always in an ultimate collaboration towards one probable
single goal.  What is that Goal?

Y. Contreras
yssmlp from hotmail.com
May, 2007

[ Accessed from http://www.geocities.com/yssmlp/ii.htm ]


1. The American Heritage Dictionary of the English Language (Fourth 
2006, Houghton Mifflin Company.

2. Wordnet 3.0, 2006, Princeton University.  [Available at: 
http://wordnet.princeton.edu/ ;
accessed May 7, 2007.]

*. Uncited/unavailable reference.  [**To add.]


Now you can see trouble…before he arrives 

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