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PRESS RELEASE: New research into novel vaccines against ovine enzootic abortion

A new vaccine being developed against ovine enzootic abortion by scientists at the Moredun Research Institute has shown very promising results in laboratory trials being able to protect against abortion caused by the bacteria Chlamydia abortus without the risk of causing infection in the animal.

Ovine enzootic abortion (also known as chlamydial abortion) is the most common infectious cause of abortion in sheep in the UK and many countries worldwide. It is caused by the bacteria Chlamydia abortus which invades the placenta during pregnancy. Infected lambs, placentas and excretions provide a source of infection to other susceptible ewes through ingestion and inhalation. A high level of environmental contamination by infected ewes in lambing pens or fields is thus an important link in the spread of disease, making the hunt for an effective vaccine important for biosecurity.

Dr David Longbottom, leading the study from Moredun said:

“We are very encouraged by the results we have seen with the new vaccine as it is able to induce effective immune responses in sheep protecting against abortion and because the new vaccine is not live, it will not cause infection in vaccinated animals, giving additional safety benefits.”

The team are currently looking to further optimise the vaccine formulation to make additional improvements and continue their work to help protect ewes against ovine enzootic abortion.

Professor Julie Fitzpatrick, Scientific Director, Moredun Research Institute said:

“Ovine enzootic abortion is a very serious disease for the sheep industry, and we are hopeful that this new research may lead to a new safe and effective vaccine. In the meantime, we would strongly advise all livestock producers to keep vaccinating their flocks with the currently available vaccines and take advice from their farm vets to reduce the risk from Chlamydia abortus.”


The full article can be viewed in the journal Vaccines, vol. 9, issue 8 (part of the Multidisciplinary Digital Publishing Institute, MDPI)

This research was funded by the Scottish Government Rural and Environment Science and Analytical Services (RESAS) division. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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