Campylobacter jejuni

Last edited 02/2020 and last reviewed 12/2021

Campylobacter jejuni food poisoning is characterised by a prodromal malaise, abdominal pain, diarrhoea, with vomiting being uncommon. The problems are due to multiplication organisms within the gut and the release of endotoxin, with symptoms occurring after 2 to 5 days.

The loading dose is 10,000 organisms, which colonise the jejunum, ileum, and colon with local invasion of the epithelium. There is sometimes production of a cholera- like toxin and cytotoxins.

Cause:

• Campylobacter jejuni accounts for most cases, followed by Campylobacter coli
• C. fetus and C. lari are uncommon causes but may cause severe illness in immunosuppressed individuals

Reservoir:

• Gastrointestinal tract of birds (especially poultry) and mammals (e.g. cattle, sheep, domestic pets); C. coli is particularly associated with pigs
• Campylobacter spp. cannot multiply outside the host but may exist in environmental sources such as soil, manure and water sources

Epidemiology:

• Campylobacter species are the commonest bacterial cause of infectious gastrointestinal disease in developed countries and one of the most common causes of traveller’s diarrhoea in the UK
• The infection follows a seasonal pattern in temperate regions with a peak in the late spring/summer months

Transmission:

• Primarily ingestion of contaminated food or drink (e.g. inadequate cooking of raw meats and offal, cross-contamination between raw and cooked foods, raw drinking milk), or water
• The organism is unable to multiply outside a host, but food-borne outbreaks do occur.
• Transmission may also be via direct contact with infected animals e.g. domestic pets or farm animals
• Person-to-person spread may occur, but the risk is low (mainly via young children who are not toilet trained)

Incubation period:

• Usually 2-5 days (range of 1-10 days)

Infectivity:

• Cases are considered infectious whilst symptomatic

Campylobacter is cultured at 42øC in selective media.

The condition is usually self limiting but may be treated if severe with a macrolide antibiotic e.g. erythromycin or clarithromycin. Principally this is to reduce the risk of bacteraemia.

Notes:

• Infections are highest in children aged <5 years
• Groups at highest risk are those with the increased exposure to a contaminated source including occupational contact with farm animals or raw poultry or meat, overseas travellers, men who have sex with men and family contacts of a case (1)
• the infectious dose is considered to be low

Reference:

• PHE (2019). Recommendations for the Public Health Management of Gastrointestinal Infections