Veterinary questions? Ask a Vet for Answers ASAP
Hi, Welcome to Just Answer. I'm Chris, a small animal Vet based in the UK. I am reviewing your question and will get back to you as soon as possible
Sorry to hear of this with your horse. Whilst most horses will clear the strangles infection after 6 weeks, around 10% of horses become 'persistently infected' this means that they show few or no clinical symptoms but remain carriers of the disease and can spread th infection to other horses. There is a chance that this is the case with your horse, especially as the testing is picking up lower levels of bacterial dna.
Hopefully your horse may just be taking a longer time to clear the infection. Repeated lavaging of the gutteral pouches to help remove pus can also help with this.
I hope that answers your question? Please let me know if you need any further help or advice.
Use of antibiotics is contraversial, antibiotics (if needed) are usually given by injection and can be required for 2 months. Antibiotics are not generally given as they can actually prolong the course of the illness in many cases, but if you horse is failing to clear the infection naturally then this could possibly be considered. Certainly isolating your horse from others until he tests negative would be advisible.
Yes that can certainly help, as can removing impacted pus. But ultimately the immune system has to erridicate the infection