Getting to grips with campylobacter

FSA expert, Gael O’ Neil tells Farmers Weekly all about campylobacter.

What exactly is campylobacter and how does it relate to poultry?

• Campylobacter is a bacterium that lives in the avian gut, as it thrives at a temperature of 42 degrees.

Generally, it does not cause disease in the birds themselves, but if it is ingested by humans it can lead to severe diarrhoea and stomach cramps, which can last for up to two weeks.

How extensive is the problem in humans?

• Campylobacter is the number-one cause of food-borne disease in the UK. Just in England and Wales we estimate that there are about 300,000 cases a year out of about 1m instances of food poisoning.

Of these, about 15,000 result in hospitalisation and there are even about 80 deaths. It is also estimated that 60-80% of campylobacter food poisoning is related to chicken. If we can get on top of this, we will be making a major contribution to improving human health.

And how widespread is it in the poultry sector?

• A recent report by the European Food Safety Authority showed that, in the UK, some 75% of broiler flocks are infected with campylobacter.

It also showed that 86% of carcasses had the bacteria immediately post-slaughter, while our samples have found it in 65% of chicken meat at retail.

So why the drop at retail level?

• This is probably down to two things. First, we believe levels of bacteria tend to reduce once the meat is put into cold store, as campylobacter is sensitive to low temperatures. Second, our samples included imported poultry meat.

What is the experience of other EU member states?

• The EFSA report showed a wide range of incidence levels. The lowest were found in the Scandinavian countries, where fewer than 10% of flocks have campylobacter. The EU average is over 70% and in Ireland it is more than 90%.

Last month you arranged for experts from 14 different countries to meet in London and share their experiences of tackling campylobacter. What did you learn?

• First and foremost, we learnt that it is possible to get on top of the disease, but it takes a multi-tiered approach involving everyone in the supply chain. New Zealand, for example, has cut the level of campylobacteriosis in the human population by two-thirds in just three years.

So what works at farm level? What should our poultry producers be doing?

• The biggest single thing is to tighten bio-security. The Scandinavians in particular have shown how maximum biosecurity and minimum contact with the birds pays dividends.

It’s a fact that campylobacter is not found in chicks – it only appears after about three to four weeks, so it must be brought in from outside. In Scandinavia the farms all have separate changing areas – no-one goes into a poultry shed in the same clothes they came to work in.

And in Iceland, we heard that they put up nets to keep flies and midges out during the summer months. That too may help.

Another possible factor is “thinning” which we practice in the UK, when people go into poultry houses to take out a proportion of the birds to provide chickens of different weights for the market. That can’t help.

Is any one production system better or worse than any another?

• Outdoor systems are more prone to campylobacter than indoor systems due to environmental contamination.

For example, in France about 77% of the flocks are contaminated, but in the free range and organic sector, it is close to 100%. Having said that, the type of campylobacter found in outdoor flocks (campylobacter coli) causes much less human disease than that found in indoor flocks (campylobacter jejuni).

Are there any medical interventions farmers can use to reduce the problem?

• There have been some trials to introduce organic acids in drinking water for birds, but this has not been very successful.

Really we need a vaccine, as we have for salmonella, but that is still 10-15 years away.

And what about further along the supply chain?

• Slaughterhouses have to improve their performance too, especially in the evisceration area which is where campylobacter gets from inside the bird to the outside.

In places such as New Zealand and the USA they make use of anti-microbial washes to treat the meat, but this is not allowed within the EU.

Here we can only use potable water or steam, though we are looking at naturally occurring substances, such as citric or lactic acid. clearly there is a debate to be had.

Do retailers have a role to play?

• Most certainly. For example, they should adopt leak-proof packaging more fully.

The problem is not so much people eating undercooked chicken, as it is cross-contamination of things like salads and vegetables through contact with the bacterium.

Adopting modified atmosphere packaging – for example by increasing CO2 levels – could also help.

So where do we go next?

• There is a joint government-industry working party set up and we will be meeting soon to decide what recommendations to take forward in the short, medium and long term.

By the end of the year we hope to have formal targets for the reduction of campylobacter.

Do you have a final piece of advice for poultry farmers?

• Yes. Impose stricter biosecurity. It’s all very well having the protocols in place, but unless they are observed rigidly, campylobacter will find a way in.