Post-weaning Sneezing


Causal agent

Multiple bacteria and viruses.  Includes, Bacteria- Pasturella multocida, Bordetella bronchiseptica, Haemophilus parasuis, Actinobacillus pleuropneumoniae, A. suis, streptococci spp., pseudomonas spp, proteus and other environmentally originated bacteria. Various mycoplasmas’.  Chlamydia involved in the conjunctivitis.    Viruses - Inclusion Body Rhinitis and PRRSv.  None of these agents are specifically required to cause the sneezing.

Age group

Classically 10-30 days post-weaning

Clinical signs

The group of weaned pigs present with mild to severe sneezing.

The symptoms will progressively reduce within 2-3 weeks.

The sneezing may progress to middle ear disease.

Conjunctivitis may be seen in several pigs.  May be severe.

Weaner small pen                        Conjunctivitis 6a


Mixing of the ‘normal’ microflora of the nasopharynx between different litters of piglets.


Nasal contact.

Post-mortem Lesions

A non-progressive rhinitis.  Conjunctivitis.  The nasal cavity may be filled with purulent material.


Clinical examination.  Weaners rarely die specifically associated with post-weaning sneezing. 

Treatment and Control


Mixed infection.  Specific treatment supportive and generally unrewarding.  Often consider almost ‘normal’ on most farms.  The problem disappears by 30 kg weight



Review management of the farm building.  Avoid chilling and drafts.

Review PRRSv stablisation programme

Combine litters pre-weaning

If sneezing also in farrowing house – review atrophic rhinitis controls

Common differentials

Progressive Atrophic Rhinitis.

Zoonotic implications

There are no zoonotic implications. Individual components may be pathogenic in man