Leeches

[leechhepc]

I found this study (seems from a reputable institution) which claims that leeches can store blood-borne viruses such as Hep C or HIV in their gut for months.
So if they bite another person and regurgitate the blood (due to application of salt/heat to remove them) can infection occur ?.

Can such viruses, particularly Hep C (which I assume is not as fragile as HIV) survive in the leech ?


This is the study link:
http://link.springer.com/content/pdf/10.1007%2FBF02351867

[Idyllic]

Wow that is an old article. I remember stumbling over a few articles about leeches when I was trying to understand venous insufficiency. I am not sure the European medicinal leech is a species of leech one would encounter ..like NYGirl says, in a swamp (or wherever leeches live).

http://en.wikipedia.org/wiki/Hirudo_medicinalis
The risk of blood-borne transmission is not addressed

I doubt routine use of them in medicine is common but it is not unheard of:
http://dermnetnz.org/procedures/leeches.html
Hepatitis is not mentioned as a complication.


Look, they are $4.95 each!
http://www.cadth.ca/products/environmental-scanning/health-technology-update/issue3/creep-crawlers#2

Notice the treatment risks on the bottom:
Treatment Risk

The risks associated with leech therapy include infection, excessive blood loss requiring transfusion, migration of leeches into body orifices and allergic reactions to leech saliva. Leeches have the potential to transmit blood-borne viruses such as hepatitis and HIV. They are intended for single use only and must be handled as biohazardous waste.[2] Prophylactic intravenous antibiotics are recommended to protect patients against leech bacteria.[2]

***It only says "Hepatitis." I did not follow the trail and click on the link in reference at the end of the article but that might be a place for you to start if you are curious.

[pooh55811]

I never found the article leechhepc posted the link to. The link that leechhepc posted  brings a person back to this thread on MH. So it is unclear what is in the article that leechhepc posted a link to.

Plus, the only article I found mentions leeches as a possible vector for pathogens,  but Hep C is not mentioned.

I tend to agree that without studies, the discussion is hypothetical.

[flcyclist]

Unless there is data to support the possibility of HCV transmission, the hypothetical what-if debate is a waste of time.  Hepatitis B is a very different virus and can't be compared to HCV.  There are many blood sucking pests, including insects that can transmit diseases, but none can transmit HCV.  

Is this just a curiosity that you are exploring?

[HectorSF]

Hepatitis C is NEVER mentioned in the article. So why start out with a bogus premise 'leeches can store blood-borne viruses such as Hep C or HIV'
The actual test reads as 'In African leeches from Cameroon, blood was serologically positive for human immunodeficiency virus (HIV) and  hepatitis  B;..'

This is not a hepatitis C or HIV forum.

Many people here are suffering to various issues because of hepatitis C infection. Please show some respect for people dealing with real, tangable issues issues.

Hector

[leechhepc]

Thanks pooh55811,
So you see from the article that there is a real issue to be answered.

I wonder if anyone (perhaps a doctor/specialist) can offer a clear and definitive answer as to whether leeches pose a risk as a vector for Hep C.

[pooh55811]

I found the following article. Hep B appears to be able to survive in the leeches (as do many other pathogens) but there is no mention of Hep C. I did not find much information concerning Hep C and leeches.It is a good question because leeches are very common in some areas, even in areas a person may not think they would be, because they live in many fresh water lakes and rivers. As an example, many lakes in the Upper Midwest contain leeches. In fact, the third largest lake in MN is named Leech Lake. And, yes, it is full of leeches, some a foot or more long. And yes, people swim in it.

http://en.wikipedia.org/wiki/Leech_Lake

No one mentions the leeches on any site on the net, LOL. But they are there.


"Experiments on the possible role of leeches as vectors of animal and human pathogens: a light and electron microscopy study.
Nehili M, Ilk C, Mehlhorn H, Ruhnau K, **** W, Njayou M.
Source

Department of Zoology and Parasitology, Ruhr-University Bochum, Germany.
Abstract

The presence and survival of pathogens inside the gut of leeches were studied by means of light and electron microscopy. In African leeches from Cameroon, blood was serologically positive for human immunodeficiency virus (HIV) and hepatitis B; blood of Hirudo medicinalis bought in German pharmacies contained up to 11 different species of bacteria. In experiments done at low (3 degrees C) and high (22 degrees, 32 degrees C) temperatures, it was shown that ingested red and white blood cells survive for long periods. The time was prolonged to at least 6 months in cases in which the leeches were stored at 3 degrees C. The same effect occurred with pathogens. Bacteriophages (viruses of bacteria) and bacteria persisted in large numbers for at least 6 months in the gut of experimentally infected leeches. Protozoan parasites such as Toxoplasma gondii, Trypanosoma brucei brucei, or Plasmodium berghei were even capable of reproducing inside the gut of the leech. In the case of Plasmodium parasites, this proceeded at low (3 degrees C) and high (22 degrees C) temperatures until all erythrocytes were used up. These parasites survived as long as the erythrocytes and lymphocytes were of good shape, i.e., around 5-6 weeks p.i. Single stages survived longer, especially at low temperatures. However, electron microscopy studies gave no hint of penetration of such pathogens into the unicellular salivary glands, which would initiate a direct transmission. Such transmission, however, is possible--many fish leeches directly transmit several blood parasites--when the leeches are squeezed during skin attachment or when they are manipulated by dropping salt solution on their backs while they are sucking. Consequently, the leech is a potential vector of many pathogens, especially in regions with an endemic spread of human and/or animal pathogens."

http://www.ncbi.nlm.nih.gov/pubmed/8073013

[nygirl7]

I dont know but I dont often get bitten by leeches, in fact I try to avoid things like that.  Unless you swim in swamps or wherever you find them - no sense worrying about it.