Swelling after being bitten by a squirrel cannot be ruled out as a possibility of infection and should be treated promptly by a doctor. Since the location of the bite and the depth of the bite are not provided, only an approximate account can be given.
Go to the hospital to be evaluated by a medical professional for adjacent structural injuries, especially deep puncture wounds to the head, neck, torso, or adjacent joints. The wound should also be carefully evaluated for the presence of foreign bodies and for neurovascularity in the distal region of the wound.
Determine the chance of wound infection based on the findings. The time to infection after a rodent bite is usually short (approximately 12 hours), and bites may result in superficial infections (e.g., cellulitis with or without abscesses) or deep infections (abscesses, septic arthritis, osteomyelitis, tenosynovitis, or necrotizing soft-tissue infections), which should be taken seriously enough to warrant prompt treatment.
In addition to the above, signs suggestive of deep infection include persistent or progressive pain for several days after the initial bite, pain with passive movement, pain disproportionate to the findings on examination, twinges, swollen joints, systemic illness (fever, hemodynamic instability), and signs of persistent infection despite initial wound management and antibiotics.
If the animal bite victim has no clinical evidence of infection (based on physical examination or imaging), treatment should include wound management, removal of foreign bodies, and assessment of the need for antibiotic prophylaxis, tetanus prophylaxis, and rabies prophylaxis.
It is recommended to seek medical attention after a bite to avoid delays.