Q&A: Toxoplasma - what can be done?

Should I get rid of my cat?

Cats are the ultimate source of toxoplasma and are the only species in which the parasite completes its lifecycle. However, it is not clear how the parasite is transmitted to people. Only 1 per cent of cats are infected at any one time, and the highest risks animals are kittens that have just learned to kill wild mice and birds. Sensible hygiene, and avoiding cat litter if you are pregnant, should be enough to limit the risk.

I have small children. Should I complain to my neighbours about their cats coming into my garden?

It would be a good idea to cover children’s sandpits at night or when people are not around. Studies show they are rich in toxoplasma eggs if left unprotected. Anti-cat devices may help to reduce the risk of cats defecating in your garden.

Are some people more at risk than others?

Women who are pregnant for the first time and get infected with toxoplasma at that moment are at high risk of passing on the infection to their unborn baby. This can cause serious, life-long problems for the child and can sometimes lead to miscarriages. Likewise, people with compromised immune systems cannot easily fend off an infection and may be vulnerable to a latent infection acquired many years previously. The late dementia of some Aids patients may be the result of latent toxoplasma infection.

Can the parasite be caught by stroking cats? Or only by touching their faeces?

Touching an infected cat carries a risk of the parasite being ingested. Accidentally touching its infected faeces carries an even higher risk if hands are not washed thoroughly. But not all cats are infected.

What steps can I take to reduce the risks of catching the parasite from food?

Wash any vegetables thoroughly if they are to be eaten raw. A high proportion of vegetarians are known to be infected with toxoplasma, so vegetables must be considered to be a source of infection. Meat can also harbour toxoplasma tissue cysts, and lamb in particular is believed to be a particular risk. The official advice to pregnant women and immune-compromised patients is to cook all meat well and not to eat it rare. Some experts suggest this should be standard advice for the wider public.

What are the main symptoms of toxoplasmosis?

Most people show no obvious symptoms. If symptoms develop they usually occur within about one or two weeks after initial contact. The disease can affect the brain, lungs, heart, eyes or liver and can in healthy people result in flu-like symptoms, such as sore throat, headaches and fever.

What should I do if I suspect that I am infected?

Go to a doctor.

Can toxoplasmosis in humans be treated?

Toxoplasma can be treated with a range of drugs, including antimalarial medicines and antibiotics. Most people with a healthy immune system recover, but the disease may return in later life due to latent infection.

How do I find out if my cat is infected?

You cannot, at the moment, as no commercial test is available.