Why you should avoid lambing if you’re pregnant
Lambing season is upon us and the lovely sight of new-born lambs brings a welcome spring picture after the long winter. However, lambing can pose quite a significant risk to pregnant women.
There are multiple bacteria, parasites and viruses that are present in bodily fluids that can potentially cause problems in humans. This is also true for recently born lambs, ewes that have recently given birth and any contaminated material such as clothing, bedding, and equipment. These diseases can be significantly more serious in pregnant women. As there is a widespread risk of potentially contracting disease from these sources, it is advised that pregnant women stay away from all reproducing flocks. Preferably, they should also avoid milking ewes.
These risks are not solely sheep related – similarly goats and cattle that have recently given birth also carry similar infections. Many of these can present risk to mothers-to-be. Please note it is not only spring-time that these risks are apparent; they are year round, however spring is when the majority of lambs are born.
How to reduce risk to pregnant women:
To reduce risk of disease, pregnant women should follow these measures:
- Do not help to lamb (or help cattle or goats to give birth either)
- No contact with new-born lambs, kids, or calves
- Don’t have any contact with the placenta or any other birthing materials
- Don’t touch any equipment, bedding or clothing that has been in contact with newly born lambs, kids, calves or pregnant animals
- Ensure people that you come into contact with have been wearing adequate PPE and have correctly sanitised themselves, their clothing, and all equipment
- Don’t wash contaminated clothing yourself or have contaminated shoes in your house
Infectious agents present in bodily fluids and new-born lambs can be zoonotic. This means they can infect humans and other animals, causing disease and sometimes abortion.
Some infectious agents that pose a risk in the UK are:
Listeriosis is caused by the bacterium Listeria monocytogenes (which we covered in this article last week). Sheep can catch this from eating poor quality silage during the winter months. As such, it is more common around lambing season. The bacterium can cause septicaemia (blood poisoning), meningitis (inflammation of the membranes surrounding the brain), encephalitis (inflammation of the brain) and abortion. This disease is colloquially referred to as ‘circling disease’ as it typically affects only one side of the brain.
Chlamydia or Enzootic Abortion (EAE)
The bacterium Chlamydiophila abortus, formerly known as C. psittaci, causes EAE. Generally, infected sheep or birds introduce it to a flock after coming into contact with contaminated material. Infected sheep usually will not show signs until the year following their infection, when they abort. Birth fluids, bedding and newborn lambs are heavily contaminated with the bacteria. Other sheep are drawn to the scent of amniotic fluid and so also tend to ingest the pathogen. Infection in humans can lead to stillbirth.
The bacteria Coxiella burnetii infects ruminants worldwide and can also infect cats and dogs. Most infections in livestock are asymptomatic, however they can result in still birth. For this reason, it might not be obvious if your flock has the disease. Q fever spreads by contact of abrasions with bodily fluids or by inhalation of spores. Therefore even being in the presence of ewes that are lambing can be dangerous. Q fever infection in humans can result in premature birth, a low birth weight and even miscarriage.
The parasite Toxoplasma gondii causes toxoplasmosis. Infection in sheep typically occurs when sheep eat feed contaminated with cat faeces. But they can also pick it up from contaminated soil. Toxoplasmosis presents in sheep through lamb losses, however if contracted by humans, it has a different pathology. If a woman catches toxoplasmosis while pregnant, it can have serious complications for her baby once it is born. The effect is not immediately apparent but can lead to retinochoroiditis, learning disabilities, ocular complications, and hearing loss later on in life.
Other notable diseases than can present risk to pregnant women are infection with Salmonella, Campylobacter, tick borne fever, and Border disease. Remain vigilant and please give lambing season a wide berth if you are pregnant.
References and further reading:
Osborne B. (2015). The hidden hazards of spring: why pregnant women and the immunocompromised should avoid lambing. The British journal of general practice : the journal of the Royal College of General Practitioners, 65(632), 144. https://doi.org/10.3399/bjgp15X684121