News & Features — 17 June 2013 at 1:06 pm

Seal Bites

Sam Crimmin / Medical Officer / South Georgia

The Antarctic tourist trade is thriving. The visitors share the landing beaches with the local wildlife and Elephant, Weddell, Crabeater, Leopard and Fur seals are just a few of the species they might encounter.

More and more polar tour operators are now including South Georgia on their itinerary. This small island is appropriately advertised as the Galapagos of the South and wildlife abounds. However, in the austral summer, beaches can become impassable as fur seals return to their breading grounds.

Sealer’s Finger

‘Sealers’ or ‘Spekk’ Finger, a well known complication of seal bites was first reported in Norway by Bidenkamp in 1907. The condition occurs when a seal bite leads to cellulitis and joint inflammation. Historically this was a serious problem often leading to a thickened contracted joint and eventually amputation of the digit. Though labeled Sealers’ Finger, it is not necessarily limited to the hand.

It was originally thought that the disease was caused by the gram-positive Erysipelothrix rhusiopthiae. However in 1998 Baker et al.  reported the isolation of a Mycoplasma species (Myoplasma phoacerebrale) from a case of Sealers’ Finger in an aquarium worker.

The debate over the causative organism makes antibiotic choice for active infection and prophylaxis difficult. Erysipelothrix rhusiopathiae is responsive to penicillins, cephalosporins and erythromycin. But since Mycoplasma lacks a cell wall, the disease does not respond to beta-lactam antibiotics but instead requires a tetracycline. Inadequate antibiotic treatment of either of these organism could lead to local spread resulting in tenosynovitis, osteomyelitis, and in the case of E. rhusiopathiae there is a risk of endocarditis.

Treatment Protocol

  1. Irrigate copiously, using tap water or normal saline
  2. Remove any foreign bodies
  3. Perform debridement of dead tissue back to bleeding edges
  4. Raise and elevate the limb
  5. Antibiotics should be given; doxycyline and metronidazole are probably the best
  6. Check tetanus and give if appropriate
  7. Review the wound at 24 – 48 hours in ALL cases