‘It sets up camp in your intestine’: Holidaying in the US? Here’s how to avoid the cyclospora parasite

Ah, America. Land of sun, sea, national parks, mountains, historic cities… and, at the moment, a nasty infection known as cyclosporiasis. If you’re about to head to the US, Dr Todd Green, lead GP at Kry Livi, reveals everything you need to know about this tiny parasite that’s wreaking havoc on digestive systems stateside (and, in case you’re wondering, panic not – cyclosporiasis isn’t contagious and is easily avoidable with a few sensible precautions).

What actually is cyclospora?
It’s a tiny parasite – cyclospora cayetanensis – that’s too small to see and it sets up camp in your small intestine, Dr Green explains. You catch it by swallowing food or water that’s been contaminated, usually with traces of faeces (poo) somewhere along the line. In the US, it’s nearly always traced back to fresh produce – think salad leaves, berries, herbs like basil and coriander. It’s been a bad year for it: this year’s US case numbers are running roughly six times higher than the same time last year, which is why it’s suddenly in the headlines.

Fortunately, explains Dr Jarvis, there is no evidence of person to person transmission.

How would I know if I’d got it?
Honestly, you’d know, says Dr Green. The standout symptom is watery diarrhoea – and, to be blunt, it can be frequent and pretty explosive. Alongside that, you often get stomach cramps, bloating, nausea, a loss of appetite, real fatigue and sometimes weight loss. Fever and vomiting can happen, but they’re less common. Two things make cyclosporiasis a bit sneaky: firstly, symptoms usually don’t show up for a week or so after you’ve been exposed, so if you get ill you might not connect it to that salad you ate last week; and secondly – this is the real giveaway – it can come in waves. The diarrhoea eases off, you think you’re over it and then it comes back. Without treatment, this can go on for weeks or even months. If that pattern sounds familiar, that’s a flag to get checked.

Keeping yourself hydrated is important.

When does it actually become something to worry about?
For most healthy people, like most stomach bugs, it’s genuinely miserable, rather than dangerous – it’s not usually life-threatening. The catch is that if you leave it untreated, the symptoms can drag on and keep recurring, says Dr Green. That’s a long time to feel dreadful and can easily wipe out a holiday. The most important risk is dehydration. That much diarrhoea means you’re losing a lot of fluid and electrolytes – and that’s what tends to land people in trouble.

While there's no doubt it's unpleasant, and there have been a number of hospitalizations in the US, there have been no deaths so far explains Dr Jarvis: 'even given the current outbreak, the likelihood of catching it in the US is fairly small and US public health bodies are working hard to identify and eliminate the cause.'

How’s it treated?
The good news is a simple antibiotic course reliably clears it up, so it’s very treatable once it’s spotted, explains Dr Green: 'I’d recommend seeing a doctor if your diarrhoea is severe, lasts more than a few days, keeps relapsing or if you’re getting signs of dehydration: dizziness, a dry mouth, dark urine, not weeing much.' Don’t wait around if it’s a child, someone elderly or anyone with other health conditions or a weakened immune system, he explains – see a doctor ASAP. One practical tip if you do get tested: the standard tests don’t pick this up. Your doctor has to specifically ask the lab to look for cyclospora – so if you’ve been in an affected area, mention that.

Can I catch it from another person?
You catch it by eating or drinking something contaminated – it doesn’t really spread from person to person. The parasite needs days outside the body to become infectious, so you can’t catch it just by being near someone who’s ill, even by sharing a room. The CDC [the US Centers for Disease Control and Prevention] have been really clear on this: the source is what you eat or drink, not casual contact with someone who’s sick. So, if a travel companion goes down with it, you don’t need to quarantine them; you just both need to be careful about food and drink.

Give fresh produce a proper rinse under running water

I’m off to America – how worried should I be and what can I do?
Let’s keep it in perspective: yes, it’s a genuinely bad outbreak year in the US, but for the average traveller, the risk is still low and this is very avoidable with a few sensible habits.
* Give fresh produce a proper rinse under running water – even the bagged, ‘pre-washed’ salad. Worth knowing, though: washing helps but doesn’t guarantee you’ve got rid of it, because the parasite clings on tightly.
* When in doubt, cook it or peel it. Heat kills the parasite – properly cooked produce is safe and peeling fruit and veg yourself removes the risky surface. The traveller’s rule of thumb still holds: cook it, peel it or skip it.
* Be a bit wary of the classic culprits – leafy salad mixes, fresh berries, basil and coriander have all been linked to past outbreaks. I’m not saying never touch a salad in America, just be choosier about where, and lean towards cooked options if you’re somewhere you’re not sure about.
* Watch what you drink. Don’t swallow water from pools, lakes or untreated sources and stick to bottled or properly treated water if you have any doubt.
* Wash your hands with soap and water before you eat or handle food and again afterwards. Simple, but it makes a big difference to preventing these sorts of infections.
* Finally, know the plan if you do get ill. Keep your fluids up and consider oral rehydration sachets from a chemist. If the diarrhoea is severe, drags on past a few days or keeps coming back, see a doctor and specifically ask about cyclospora. The bottom line is don’t let this ruin your holiday. Cyclosporiasis is unpleasant but avoidable; it won’t jump from person to person, and it’s very treatable. A bit of common sense with what’s on your plate and in your glass covers most of the risk.