TOXOPLASMOSIS

TOXOPLASMOSIS
HIV/AIDS QUALITY OF
CARE INITIATIVE
(HAQOCI)


Clinical Epidemiology Resource & Training Centre
(CERTC)
College of Health Sciences
University of Zimbabwe
(In Conjunction with the Ministry of
Health & Child Welfare)

P.O. Box A178
Avondale
Harare
Tel: +263-4-791631 ext 2461/ 707445
Telefax: +263-4-791995
Opportunistic Infection Prevention Clinic
E-mail: haqoci@mweb.co.zw
Clinical Epidemiology Resource & Training Centre
(CERTC)
Supported by U.S. Centers for Disease Control and
College of Health Sciences
Prevention (CDC)- Zimbabwe AIDS Program
University of Zimbabwe
Brochure Series QOC 18

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Toxoplasmosis
Toxoplasmosis (also known as ‘toxo’), a common infection throughout the world, is
coordination and changes in vision. These symptoms can progress to coma and death
caused by the parasite toxoplasma gondii. In people with normal immune function,
unless the infection is diagnosed and treated in time.
toxoplasma organisms remain in the body tissues as cysts that do not cause disease.

In persons with impaired immunity, however, toxoplasma can multiply and
Toxoplasma infection affecting parts of the body other than the brain is uncommon. In
cause disease in the brain and sometimes other body organs.
such cases, symptoms depend on the organ affected. Infection of the eye is seen in peo-

ple with AIDS, and such a person will notice that their vision is worsening in one eye.
Facts

•
Humans can contract toxoplasmosis by swallowing organisms from
How is toxoplasmosis diagnosed?
contaminated food or cat faeces
If you have symptoms that suggest toxoplasmosis and your CD4 count is below 100/ul,
•
your doctor will be likely to order a CT or MRI scan of the brain. If the scan shows abnor-
Most toxoplasmosis in HIV-infected persons is the result of reactivation of an
malities suggestive of toxoplasmosis, you will be prescribed medications to treat the con-
old infection, which usually involves the brain
dition. If your symptoms do not improve within a few weeks, another disease may be

causing the symptoms, and further diagnostic tests may be necessary.
Symptoms of toxoplasmosis may include fever, headache, confusion, sleepiness,

weakness or numbness in one part of the body, seizures and vision problems
If you do not have symptoms of toxoplasmosis, but wish to know if you are carrying in-
Toxoplasmosis is most commonly treated with the drug co-trimoxazole (See bro-
active toxoplasma cysts, a blood test called the Toxoplasma antibody test, can deter-
chure on Cotrimoxaxole Prophlyaxis)
mine this. A positive test result confirms the presence of toxoplasma antibodies in the

blood, and that there must have been a past infection. This does not necessarily mean

you have active infection, but it does mean you may be at risk for toxoplasmosis in the
Humans can contract toxoplasmosis in the following ways
future. A negative test result indicates that you are at very low risk of developing
•
Through contact with infected cat stools. Domestic cats can transmit
toxoplasmosis.
toxoplasma by passing an infectious form of the parasite, oocysts, in their

faeces. Toxoplasma is only present in the faeces for a few weeks after the cat
How is toxoplasmosis treated?
is first infected. Like humans, cats rarely have symptoms when first infected,
Toxoplasmosis is most commonly treated with the drug co-trimoxazole (trimethoprim
and there are no good tests available to determine if your cat is infected.
and sulfamethoxazole). High-dose therapy is continued for four to six weeks, followed
•
By swal owing organisms in contaminated food or picked up on dirty hands,
by lower dose maintenance therapy for at least 12 weeks.
eating undercooked meat or eggs, or drinking unpasteurised milk containing

tissue cysts from infected animals.
Sulfamethoxazole may sometimes cause allergic reactions, including rash, nausea, vom-
•
Women who become infected with toxoplasma during pregnancy sometimes
iting and diarrhoea and some reactions can be control ed by taking anti-histamines
transmit it to their unborn babies.
(anti-al ergy drug). Trimethoprim can cause low blood counts in some people. To

counter the possible effects of trimethoprim on the bone marrow, folate supplements
How can toxoplasmosis affect people with HIV/AIDS?
can be taken. If you cannot tolerate co-trimoxazole, clindamycin and pyrimethamine
Toxoplasma is common in the environment, so many HIV-infected people have the
may be prescribed instead. Other drugs sometimes used to treat toxoplasmosis include
inactive form of the parasites (cysts) in their bodies, usually in brain or muscle tissue.
clarithromycin, azithromycin, dapsone and atovaquone. These may be considered if the
These infections stay inactive as long as the infected person’s immune system is
standard treatment is ineffective or causes unacceptable side effects.
strong. However, in advanced HIV disease (CD4 cell count less than 100/ul), the

immune system may not be able to control the infection and illness results. Up to
How can I help prevent toxoplasmosis?
half of HIV-infected persons with AIDS have toxoplasmosis infection, and those with
Get tested for toxoplasmosis, and if you have a negative antibody test, you can help
a CD4 count under 100 contract toxo-related illness. Most toxoplasmosis in
avoid toxoplasma infection by taking certain precautions, such as:
HIV-infected individuals is the result of reactivation of an old infection, which

usually involves the brain.
•
Don’t eat undercooked or raw meat or eggs and don’t drink unpasteurised milk.

•
Wash your hands before eating or handling food, as well as after touching raw
Symptoms and signs of toxoplasmosis
meat and being outdoors or gardening.
Symptoms of toxoplasma infection of the brain may include headache, fever,
•
Wash fruits and vegetables wel before eating them raw
confusion, sleepiness, weakness or numbness in part of the body, seizures, poor

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