Outbreak of Furunculosis (Boil) in Nail Salon
Title: An outbreak of mycobacterial furunculosis
associated with footbaths at a nail salon
Authors: Winthrop KL, et al.
Publication: N Engl J Med. 2002 May 2;346(18):1366-71.
In September 2000, doctors in northern California described 4
patients with persistent boils in the legs, below the knee. These
patients had all received pedicures at the same nail salon.
The authors conducted the initial study on 48 patients with boil
and 56 unaffected families and friends who had had pedicure at
the same salon as healthy control. The authors cultured a particular
type of bacteria called Mycobacterium fortuitum (or M. fortuitum)
from patients who had visited the nail salon.
After the initial discovery of the 48 patients, the authors identified
more people who In total, the authors identified 110 customers
from the salon who had boil. Cultures from 34 patients were positive
for the fast-growing mycobacteria (most are of the M. fortuitum
Most of the affected patients had more than 1 boil (median of
2 boils, some with as little as 1 and as many as 37). All patients
had had whirlpool footbaths. The authors identified shaving the
legs with a razor before footbath as a risk for infection (70%
of the patients with boil did this, versus just 30% of the healthy
Cultured from all 10 footbaths at the salon were positive for
M. fortuitum. The authors further identified that the same strain
of M. fortuitum was found from 3 footbaths and 14 patients.
In conclusion, the authors had identified rapidly growing mycobacterial
infection in people who had had footbaths and pedicures at a nail
salon. They noted that doctors should suspect this as a cause
for persistent boil after whirlpool footbaths.