Gum disease is Contagious

From AAP web site
Families and Periodontal Disease
Periodontal (gum) disease may be passed from parents to children and between a couple
Several recent studies support the association between periodontal (gum) disease and family members:
Periodontal (gum) disease may be passed from parents to children and between a couple, according to an article in the September 1997 issue of the Journal of the American Dental Association. Researchers suggest bacteria that cause periodontal disease pass though saliva. This means that the common contact of saliva in families puts children and couples at risk for contracting the periodontal disease of another family member. Periodontal disease can lead to tooth loss.M
Up to 30% of the population may be genetically susceptible to developing severe periodontal disease, according to a study published in the Journal of Clinical Periodontology. These findings could result in the early identification and treatment of at-risk patients.
Based on this research, The American Academy of Periodontology (AAP) recognizes that treatment of gum disease may involve entire families. If one family member has periodontal disease, the AAP recommends that all family members see a dental professional for a periodontal disease screening.