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Egg-borne infections of humans with salmonella: not only an S. enteritidis problem

Published online by Cambridge University Press:  27 February 2014

E.J. THRELFALL ,
J. WAIN ,
T. PETERS ,
C. LANE ,
E. DE PINNA ,
C.L. LITTLE ,
A.D. WALES  and
R.H. DAVIES
E.J. THRELFALL*
Affiliation:
Gastrointestinal, Emerging and Zoonotic Infections, Health Protection Agency Centre for Infections, 61 Colindale Avenue, London NW9 5EQ, United Kingdom
J. WAIN
Affiliation:
Gastrointestinal, Emerging and Zoonotic Infections, Health Protection Agency Centre for Infections, 61 Colindale Avenue, London NW9 5EQ, United Kingdom
T. PETERS
Affiliation:
Gastrointestinal, Emerging and Zoonotic Infections, Health Protection Agency Centre for Infections, 61 Colindale Avenue, London NW9 5EQ, United Kingdom
C. LANE
Affiliation:
Gastrointestinal, Emerging and Zoonotic Infections, Health Protection Agency Centre for Infections, 61 Colindale Avenue, London NW9 5EQ, United Kingdom
E. DE PINNA
Affiliation:
Gastrointestinal, Emerging and Zoonotic Infections, Health Protection Agency Centre for Infections, 61 Colindale Avenue, London NW9 5EQ, United Kingdom
C.L. LITTLE
Affiliation:
Gastrointestinal, Emerging and Zoonotic Infections, Health Protection Agency Centre for Infections, 61 Colindale Avenue, London NW9 5EQ, United Kingdom
A.D. WALES
Affiliation:
Animal Health and Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, United Kingdom
R.H. DAVIES
Affiliation:
Animal Health and Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, United Kingdom
*
Corresponding author: e.j.threlfall@btinternet.com
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Abstract

The principal salmonella serovar associated with infections linked to eggs and egg products in the UK, most European countries and North America is Salmonella enteritidis. However, other serovars have also been implicated in a number of egg-associated outbreaks, most notably S. typhimurium exhibiting a range of phage types. The present article reviews human egg-associated salmonellosis associated with non-S. enteritidis serovars, predominantly in the European Union (EU) but also world-wide, using information from published literature and epidemiological databases. There are also brief reviews of S. enteritidis and of mechanisms leading to egg contamination by salmonella. The numbers of egg-associated infections caused by non-S. enteritidis serovars are fairly substantial (for example 22% of outbreaks and 11.5% of more than 20,000 cases in the EU in 2008), and such infections have resulted in hospitalisations and deaths. Furthermore, in parts of the world where S. enteritidis historically has not penetrated laying hen breeding flocks, egg-related salmonellosis is a problem associated specifically with non-S. enteritidis serovars. Control measures to limit the incidence of S. enteritidis and S. typhimurium in poultry flocks are vital. It is therefore important that close surveillance of salmonellosis incidence and serovars in laying flocks is used to establish suitable biosecurity and vaccination programmes throughout EU Member States and elsewhere.

Keywords

Salmonellaegg-related infectionsS. enteritidisS. typhimuriumcontrol
Type
Review Article
Information
World's Poultry Science Journal , Volume 70 , Issue 1 , March 2014 , pp. 15 - 26
Copyright
Copyright © World's Poultry Science Association 2014 

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