Following on from our magazine article “How Much is Too Much?” in the October issue, we will be looking other pregnancy complications throughout the month here on the beijingkids blog.
What is toxoplasmosis?
Toxoplasmosis is an infection caused by Toxoplasma gondii (T. gondii), a parasite found in most warm blooded animals. Common in cats, the parasite is usually harmless, symptomless and goes unnoticed by most people who carry it. But the risk for pregnant women is more serious.
The danger for pregnant women is congenital toxoplasmosis, where the unborn child is infected via the placenta. In these very rare instances (and especially if the condition develops in the early stages of pregnancy), there is an increased risk of stillbirth and miscarriage. If the child is born with congenital toxoplasmosis they face the likelihood of health complications in childhood and later life, including developmental problems, reduced vision, hearing problems, learning difficulties and cerebral palsy.
Who’s at risk?
Because of how common the parasite is, many moms-to-be will already have immunity.
It is not possible to catch toxoplasmosis through contact with infected people, nor are you able to pass it on through breastfeeding. People at risk are those that come into contact with the animals and/or animal products known to carry the parasite. The most common causes of infection are:
- People with regular contact with cats, the most common culprits for spreading the parasite to humans. T. gondii is carried in their feces so there is a higher risk for people that are exposed to cat litter, or fruit, vegetables, soil or water that may be contaminated by cat excrement.
- People who eat or handle undercooked or raw meat, especially from grazing animals such as pigs, lamb and deer.
- People who drink products made from unpasteurized goat milk.
But the people who are most at risk are those who have not previously been exposed to the parasite. If you have been infected before, there is no risk to your baby.
In about 30 to 40 percent of cases where the mother becomes infected for the first time during the pregnancy, the child will be born with congenital toxoplasmosis. This figure can drop to about 5 percent if the disease develops around the time of conception and up to 65 percent if the infections happen during the third trimester. The overall risk remains low however, and a study in the UK suggested that only about three in every 100,000 babies are born with congenital toxoplasmosis.
And there’s good news for China-dwellers. While Beijing can be bad for your health in more obvious ways, this is one instance where living here reduces the risk you’re exposed to. It is estimated that about one third of world’s population carries T. gondii, but rates here are low. Less than 10 percent of pregnant women in China carry the parasite and of course the chances of the mother not being immune and the infection being passed onto the fetus may narrow the odds significantly from the UK figure.
What are the symptoms?
Toxoplasmosis is often symptomless, especially in otherwise healthy adults. You may have flu-like symptoms but generally, only a blood test can determine whether you’re infected.
If your child develops congenital toxoplasmosis then some of the symptoms at birth include:
- Water on the brain
- Eye infections
- Eyesight problems
- Stunted growth
What is the treatment?
Although most people with toxoplasmosis do not require treatment, a pregnant woman developing it for the first time must. Early medical attention has been shown to reduce the risk of the disease being passed on via the placenta. A common treatment is spiramycin, an antibiotic that is used to treat soft tissue infections.
If the child is subsequently born with congenital toxoplasmosis then combining pyrimethamine and sulfadiazine has been found to be effective in countering the damage caused. Some studies have shown that almost three in four babies treated this way have developed normal motor functions by their teenage years, though it is also possible that hearing and ocular problems may occur later on in life.
What can you do to reduce the risk of developing it?
Women who are pregnant or considering starting a family can undergo screening to ascertain whether they have had previous exposure to the parasite or whether they might be at risk. Although screening is routine not routine in most countries, your doctor in Beijing will be able to determine your immunity with a simple blood test.
If you are untested, or find that you are “nonimmmune” then there are sensible precautions you can take to reduce the risk of infection. Given the common places the parasite can be found, avoiding those are the most effective thing you can do according to Dr. Weijuan Wang, an obstetrician and gynecologist at Amcare Women’s and Children’s Hospital.
“It is advised not to touch pet or stray cats before gestation and during pregnancy, and examinations at these times should be made. Contact with raw meat products should also be avoided, and it is advisable to [wash your hands]with soapy water if you do," she says.
Other simple preventative measures include:
- Feeding your cat with dry feed and/or well-cooked food.
- Thoroughly cleaning fruit and vegetables before consumption.
- Wear gloves when gardening or handling soil.
- Wash kitchenware thoroughly after being used for raw meat.
- Avoid drinking unpasteurized goats’ milk.
Picture courtesy of Frank de Kleine (Flickr)