Assessment of human health risk associated with pyaemia in Danish finisher pigs when conducting visual-only inspection of the lungs Amanda Brinch Kruse a, ⁎, Marianne Halberg Larsen b , Peter Bæk Skou c , Lis Alban a a Danish Agriculture & Food Council, Copenhagen, Denmark b Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark c Lyøvej 5, 2000 Frederiksberg, Denmark abstract article info Article history: Received 5 May 2014 Received in revised form 15 September 2014 Accepted 22 November 2014 Available online 29 November 2014 Keywords: Staphylococcus aureus Staphylococcus warneri Pig Embolic pneumonia Pyaemia Meat inspection The most important lesion to be overlooked when performing visual-only inspection of the lungs is embolic pneumonia. The aim of the present study was to assess the additional human health risk represented by overlooking cases of pyaemia represented by embolic pneumonia in finisher pigs, when conducting visual- only compared to palpation of the lungs, as is the traditional meat inspection procedure. An examination of bacteria isolated from 19 finisher pigs identified with embolic pneumonia at traditional meat inspection was undertaken. From each pig samples were taken from various organs (lungs, spleen, heart, liver and kidney), from the carpal joints (A. carpi) and flexor muscle (M. flexor digitorum superficialis) on the right fore- leg. These data were included in a risk assessment following OIE guidelines. Bacteria were isolated from 78 out of 127 tissue and swap samples taken (61% positive samples). Staphylococcus aureus (N = 37) was the most frequently isolated bacterium. The predominant site of S. aureus was the lung. S. aureus was detected although less frequently in low numbers in some organs (b 100 CFU/sample) and muscle samples (b 10 CFU/sample). Only one MRSA isolate was found. Staphylococcus warneri (N = 24) was the second most commonly found bacterium. There was no predominant site and the number of S. warneri was less than 50 CFU per sample. The risk of a food-borne intoxication from S. aureus in relation to pyaemia in pigs was considered very low due to the low quantitative numbers of S. aureus in muscle tissue samples. Implementing visual-only inspection will re- duce the exposure of S. aureus due to less cross-contamination and handling of the plucks by the meat inspectors. The human health risk associated with S. warneri was considered very low, due to the limited zoonotic potential of this bacterium. In conclusion, the additional human health risk in relation to possibly overlooking pyaemia in Danish finisher pigs was considered negligible when conducting visual-only compared to traditional meat inspection. © 2014 Elsevier B.V. All rights reserved. 1. Introduction 1.1. Background Meat inspection has been conducted for more than 100 years. Dur- ing that period, the hazards have changed and infectious diseases like bovine tuberculosis and brucellosis are no longer present in several parts of the world. The current meat inspection in the European Union (EU) is to a large extent based on the hazards of the past, whereas it does not eliminate the hazards of today, such as Salmonella spp. and Yersinia enterocolitica. In addition, incision and palpation of the organs and lymph nodes, which is part of the traditional meat inspection, may even increase the risk of cross contamination with human patho- gens both within the plucks/carcass and between plucks/carcasses. Therefore, the European Food Safety Authority (EFSA) suggested that meat inspection for pigs should be visual (EFSA, 2011). According to the EU Meat Inspection Regulation 854/2004 (valid until June 2014) modifications of the traditional meat inspection of fin- isher pigs raised under controlled housing condition (implying indoor with high biosecurity) can be implemented, if it can be documented by a risk assessment that the changes will not have a negative impact on human health (Anonymous, 2004). In Denmark, three risk assess- ments undertaken by the Danish Agriculture & Food Council have al- ready dealt with the effect on human health associated with a change from traditional to visual-only inspection of finisher pigs in Denmark. The first dealt with omission of the routine opening of the heart and in- cisions into the mandibular lymph node (Alban et al., 2008). The second dealt with omission of routine palpation of the intestinal lymph nodes (Alban et al., 2010). And the third dealt with omission of palpation of International Journal of Food Microbiology 196 (2015) 32–39 ⁎ Corresponding author. Present address at: Department of Large Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Grønnegårdsvej 8, 1870 Frederiksberg C, Denmark. Tel.: +45 51 55 55 54. E-mail address: abrinchkruse@gmail.com (A.B. Kruse). http://dx.doi.org/10.1016/j.ijfoodmicro.2014.11.017 0168-1605/© 2014 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect International Journal of Food Microbiology journal homepage: www.elsevier.com/locate/ijfoodmicro