26 March 2026: Coccidiosis in lambs
Updated 27 March 2026
Applies to England, Scotland and Wales
© Crown copyright 2026
This publication is licensed under the terms of the Open Government Licence v3.0 except where otherwise stated. To view this licence, visit nationalarchives.gov.uk/doc/open-government-licence/version/3 or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: psi@nationalarchives.gov.uk.
Where we have identified any third party copyright information you will need to obtain permission from the copyright holders concerned.
This publication is available at https://www.gov.uk/government/publications/alerts-for-vets-emerging-and-endemic-disease-alert-system-eedas/26-march-2026-coccidiosis-in-lambs
1. Situation
There have been cases, in multiple flocks, of deaths due to coccidiosis in pre-weaned lambs diagnosed in the past two weeks across our APHA surveillance network.
2. Details
Coccidiosis is most commonly seen in lambs aged four to eight weeks, with disease being uncommon in lambs older than three months. Clinical signs can include diarrhoea which may contain blood or mucus, straining to pass faeces, abdominal pain, condition loss, and death. Risk of disease is dependent on the balance between immunity of the lambs, infection pressure in the environment, and other stress factors. Diagnosis is based on clinical signs and examination of faecal samples for pathogenic coccidial oocysts. Whilst oocyst counts can be extremely high, speciation is always recommended to confirm the diagnosis, as of the 11 Eimeria species in sheep, only E. ovinoidalis and E. crandallis are pathogenic. Very high counts (into the millions of oocysts per gram) can be seen with only non-pathogenic Eimeria species present for example in lambs scouring for other reasons. Postmortem examination with histopathology can also be useful.
Nematodirosis is a differential diagnosis for scouring and acute deaths in lambs in springtime, and the SCOPS Nematodirus hatching forecast should be used in combination with grazing history and other risk factors to determine the need for treatment. Whilst faecal egg counts are not useful in assessing the risk of disease due to Nematodirus battus larvae, they are an important tool to assess coccidial oocyst counts.
3. Further information
Message sent from the Surveillance Intelligence Unit SIU@apha.gov.uk