Fig. 1.

Weight (a) and joint swelling (b) in C3H/HeN mice in the four groups of mice during the experiment. Normal controls; Hg, controls exposed to HgCl₂; Bb, infected with Borrelia burgdorferi N40; BbHg, infected with B. burgdorferi N40 and exposed to HgCl₂ prior to infection. Joint swelling was calculated as the difference between the joint measure for each day and the first measure. Data represent median values.