Downstream

potentially catch the disease
from water contaminated with
the urine of infected rats, but
leptospirosis is rare in the
UK; forty-four cases were
reported in England and
Wales in 2011, of which
fifteen originated overseas,
and none was fatal.
Others swim for different
reasons. Matthew Parris made
a midnight excursion across
the Thames in 2010, just to
see if it could be done, while