According to data published by EFSA, the average prevalence of Campylobacter in broiler flocks at the community level is 71.2%, with 88% in the case of Spain (EFSA, 2010)

However, achieving this objective is a challenge today, and its difficulty is twofold, since on the one hand there are multiple routes of entry of Campylobacter into broiler houses, and also the epidemiology of the bacterium is still unknown. Hence, the sum of all this makes it extremely difficult to control it at the field level (Cox et al., 2012).

In the last decade, the effectiveness of various strategies to decrease the prevalence of Campylobacter in broilers has been investigated and evaluated, which can be grouped into two larger groups: pre-slaughter and post-slaughter. Within pre-slaughter strategies, there are different alternatives, including:

PRE-SLAUGHTER

• Biosecurity measures aimed at avoiding colonization and transmission of the bacteria between different flocks.
• Nutritional measures through the administration of various substances such as essential oils, pre- and probiotics, bacteriocins and bacteriophages.
• Passive immunization or vaccination strategies (Meunier et al., 2016).

However, despite the fact that the results of in vitro tests have been very promising, the same can't be said for the field-level efficacy in most cases. Furthermore, there is an important controversy regarding the effectiveness of each of these strategies due to the great variability of the results obtained.

POST-SLAUGHTER

In addition to pre-slaughter strategies, other possible slaughterhouse interventions have been investigated to reduce the prevalence of Campylobacter. Contamination of chicken meat occurs during slaughter and processing of broilers, from the intestinal content of animals infected with Campylobacter (Johannessen et al., 2007).

For this reason, a reduction of the order of 2 or 3 log in the microbial load of Campylobacter in the carcasses has been shown to decrease the cases of human campylobacteriosis by 30 and 96%, respectively (Rosenquist et al., 2003; Messens et al., 2007; EFSA, 2011, 2015).

Aware of the impact that this has on public health, the European Commission launched a proposal for a Regulation for the control of Campylobacter at the slaughterhouse level (Figure 1), which modifies Regulation 2073/2005 (EC, 2005). This proposal was put to effect in 2017.