Susceptible to tetanus and diphtheria? Immunize against both.

[1]  P. Strebel,et al.  Tetanus surveillance--United States, 1991-1994. , 1997, MMWR. CDC surveillance summaries : Morbidity and mortality weekly report. CDC surveillance summaries.

[2]  P. Gergen,et al.  A population-based serologic survey of immunity to tetanus in the United States. , 1995, The New England journal of medicine.