I don't do Lepto either, nor do I do Corona….. Hmmm puppy strangles??? interesting. Horses (foals get strangles...).. are you saying that the only systems is a swollen gland? What made your Vet think this was what it was? and dogs do not usually get stuffy noses... not as a general principle, they really don't get "colds" as we know them... And I would think that if the shot (which I separate also)... if a reaction would be immediately not a week later... Here is one link that I found for puppy stranges... http://www.irishwolfhounds.org/infections.htm#cell
And this is what it says…
Juvenile Cellulitis (Puppy Strangles)
This is usually contracted between the ages of 4 weeks and 4 months. Not all puppies in a litter may be affected, but the entire litter can be.
Early symptoms include lethargy, anorexia, enlarged lymph glands, redness and inflammation of the ears, swelling of the mouth and jaw, fever, blisters in the ears and around eyes, lips and nose and anywhere else on the face. These blisters become ulcerated. There can be lameness due to enlarged lymph glands in the legs, and the reason for the common name of puppy strangles is that the swelling of the lymph nodes in the neck can prevent the puppy breathing.
It used to be thought that the cause is a bacterial infection, in particular streptococcus, but cultures have never confirmed any bacterial infection (although secondary infection can occur in the lesions) and antibiotic therapy alone does not help the condition. It is now considered to have some hereditary component and to be an immune system disorder of some kind, possibly a deficiency in lymphocyte blastogenesis.
The condition does respond to large doses of corticosteroids in combination with antibiotics. If cortico-steroids are not given death is not uncommon, and permanent scarring of the affected areas can occur if they are not given early in the disease. Even caught early and treated correctly, permanent hair loss on the affected areas is not uncommon.
The condition lasts up to two weeks in puppies not badly affected, but four to six weeks in more severe cases. Some pups may require special nursing to ensure they do not become dehydrated or malnourished. It can help to treat the lesions topically so as to keep them clean and dry. Bathing the lesions with a solution of Willard Water (and giving Willard Water orally), or Calendula lotion, and applying aloe vera gel can help with healing.