The magnitude of inflammatory lesions in the hearts of coxsackie B3 (CB3)-virus infected mice can be affected by the potentially toxic heavy metals cadmium (Cd), nickel (Ni) and methyl mercury (MeHg). The infection is associated with a changed distribution, such as Cd accumulation in the spleen and kidneys. New target organs for Ni during the infection were the heart, pancreas and lungs in which inflammatory lesions were present. This increased uptake was correlated with the disturbed function of immune cells and an increased inflammatory reaction. Ni and MeHg appeared to have a direct effect on immune cells that resulted in changed natural killer cell activity and decreased mobilization of macrophages, CD4+ and CD8+ cells into the inflammatory lesions. Although MeHg increased spleen T cell activity and gamma-interferon (IFN-gamma) levels, the inflammatory lesions in the heart increased. Another detrimental effect of MeHg treatment was evident by an increased calcium and decreased zinc content in the inflamed heart, which may partly explain the more severe inflammatory lesion. The host's response, CB3 infection, changed the distribution of each metal in a specific way, a fact which may subsequently result in altered target organ toxicity and resistance to the infection.