From: wentzell@ace.acadiau.ca (LEEANN WENTZELL) Date: Tue, 30 Mar 1993 15:34:39 GMT Newsgroups: sci.med Subject: Toxoplasmosis >From: sude@isoit109.BBN.HP.COM (#Susanne Denninger) >Date: Mon, 29 Mar 1993 06:45:18 GMT >Since I haven't received any responses last time, I'm posting this again. >Nobody out there knowledgeable about this desease ? >Since I read a quite frightening article on Toxoplasmosis recently, >I'd like to have more info on that desease : >1. How dangerous is it ? From whom is it especially dangerous ? >2. How is it transmitted (I read about raw meat and cats, but I'd like to > have more details) ? >3. What can be done to prevent infection ? >4. What are the symptoms and long-term effects ? >5. What treatments are availble ? >Susanne Denninger What I know I found out after a friend of my miscarried because of this. Toxoplasmosis is a small parasite which lives apparently harmlessly in the GI tract of cats. It can be transmitted through the feces to humans, where again it appears to be harmless and usually undetected, unless the human host is a pregnant woman. The parasite will attack the fetus, usually leading to spontaneous abortion early in the pregnancy. My friend, who has three cats, found out after her miscarriage that she had this, through a blood test. She was advised to wait to become pregnant again until after her system cleared of the infection. This took, in her case, almost five years. She has since delivered two healthy babies, but she no longer changes the litter box for the cats. What surprises me is how few people know about this problem. I have many friends with cats who are pregnant or planning to be, yet have no clue. Shouldn't some literature be made available at the vets'? Standard Disclaimer: My knowledge of this is from about 7 years ago, so I might be a little off on the monor details. A good parasitology text should provide you with accurate info. Lee Ann Wentzell "Her ego wrote out cheques incredibly fast Biology Department But her personality didn't have the cash..." Acadia University The Northern Pikes Wolfville, NS, CAN From: barkdoll@lepomis.psych.upenn.edu (Edwin Barkdoll) Date: 30 Mar 93 22:50:58 GMT Susanne Denninger writes: >[...] >1. How dangerous is it ? From whom is it especially dangerous ? Not very unless you happen to be an unborn fetus or immunosuppressed. >2. How is it transmitted (I read about raw meat and cats, but I'd like to > have more details) ? Cats are the definitive hosts (Toxoplasma can complete its sexual cycle in cats, not in you, cows...). Briefly egg-like oocysts are passed in the feces of in infected _oocyst-shedding-cat_. These oocysts are NOT infective immediately but require 2-3 days before they become infective. In other words, fresh cat feces are not infective. If fecal material containing infective oocysts is eaten the oocysts "hatches" releasing the next stages which can migrate to various sites in the body -- brain, eye, fetus, muscle, etc. Although teh sexual cycle does not occur in animals other than the cat, infected tissue (meat) from nondefinitive hosts is infective. The actual infectious stage tho is different depending upon whether you are infected by ingesting cat feces or raw/undercooked meat. Cats themselves usually get it from predation or eating uncooked meat from some other source. BTW, the majority of cats have + titers to Toxoplasma, however, cats are in general infective only for a short time post infection, about 1-2 weeks after which time they are rather resistant to reinfection. In other words most cats have been exposed but very few are shedding oocysts at any one time. If you eliminate your contact with 2-3 day old cat feces the chance that you will get it from a cat is nil. >3. What can be done to prevent infection ? Cooking and freezing (!) meat is said to kill Toxoplasma. Do not feed raw meat to cats. Clean the litter box DAILY. Always wear gloves when gardening (your garden is just one big litter box to the neighborhood cats). If you are pregnant get your husband/lover etc to clean ou the litter box DAILY. >4. What are the symptoms and long-term effects ? Most infections in immunocompetent humans are asymptomatic. My parasitology book states that in certain areas up to 25% may have + titers. Same source say that the majority of congenital infections are also without signs, although more serious consequences result when infection is early in the pregnancy. Possible consequences include abortion, stillbirths, nervous system damage, visual abnormalities. -- Edwin Barkdoll barkdoll@lepomis.psych.upenn.edu eb3@world.std.com From: richard@woof.demon.co.uk (richard wheeler) Date: Wed, 31 Mar 1993 12:10:00 +0000 In answer to your questions re TOXOPLASMOSIS: The following was told to me last night by my wife who is a vet. Any mistakes are due to my lack of understanding of what she told me. 1) Toxoplasmais only seriusly dangerous to certain categories of people such as pregnant women due to the effects that transplacental transmission can have on the foetus, and immunodeficient or immunocompromised patients such as AIDS sufferers. The rest of us suffer temporary signs such as malais, fatigue, headaches, myalgia and lympadenopathy which disappears once our immune system has got its act together. 2) It is transmitted in humans by ingesting infected oocysts(eggs) usually from infected meat but also from infected faecal matierial. In humans and other intermediate hosts it can only multiply asexually and this causes inflamation and reactive changes in various parts of the body but importantly, in the placenta. The cat ( and other members of the felidae) is the only definitve host in which the sexual phase of the toxoplasma life cycle can occur and it multiplies in the small intestine producing male and female cells which are excreted as fertilized oocysts. The oocyst is not infective for 2 to 4 days but after this time it can remain viable in the ground for up tp 18 months in the form of sporozoites - there are 8 of these in each oocyst. The cat only sheds oocysts until its own immunity to the protozoan parasite develops or , rarely afterwards, if its immune system is depressed or gastrointestinal infections allow it to proliferate again. 3) Prevention of infection is mainly common sense and hygiene. Direct contact with the cat has not been implicated as a mode of transmission although infection can occur indirectly. Don't eat raw or undercooked meat. Don't touch catlitter trays if pregnant. Wash hands, implements and surfaces after handling uncooked meat(freezing meat kills most cysts). Cover sand pits. Wash fruit and veg. Wear gloves when gardening. Wash hans after handling animals. 4) Symptoms have been mentioned earlier however the most serious aspect is in the effects of transplacental retardation and chorioretinit is in children. There is a controversial view that it might be advantageous for women to be exposed to the parasite early in life so as to develop immunity before becoming pregnant. 5) Treatment in humans is usually by chemotherapy i.e. antibiosis. As an addendum it is not good to destroy all cats to control toxoplasmos but better to encourage responsible cat ownership such as not feeding uncooked meat to cats and preventing cats from hunting where practical; and to employ simple hygiene. I do not accept responsiblity if the above is incorrect. I am not a vet! It also affects sheep but that is another story. -- From: jcb (Jim Becker) Date: 1 Apr 93 01:27:16 GMT Subject: Re: Toxoplasmosis From: barkdoll@lepomis.psych.upenn.edu (Edwin Barkdoll) Sender: news@netnews.upenn.edu In article sude@isoit109.BBN.HP.COM (#Susanne Denninger) writes: >[...] >1. How dangerous is it ? From whom is it especially dangerous ? Not very unless you happen to be an unborn fetus or immunosuppressed. i had a pretty terrible time with toxoplasmosis back in 1975 when i contracted it. (probably from an undercooked hot dog). at that point in time, they didn't know what it was. at least my doctor. i spent some time in the hospital, seemingly close to death. after release, it took about eight months before i was back in terms of strength and coloration. don't think i was immunosuppressed, as generally i'm resilient to problems. correct diagnosis certainly would have helped. -jim