Bacteria are invisible to the naked eye, and degrees of white tongue coating are present in most people with and without halitosis. A visible white tongue coating does not always equal the back of the tongue as an origin of halitosis, however a "white tongue" is thought to be a sign of halitosis. In oral medicine generally, a white tongue is considered a sign of several medical conditions. Patients with periodontal disease were shown to have sixfold prevalence of tongue coating compared with normal subjects. Halitosis patients were also shown to have significantly higher bacterial loads in this region compared to individuals without halitosis. Gums
Gingival crevices are the small grooves between teeth and gums, and they are present in health, although they may become inflamed when gingivitis is present. The difference between a gingival crevice and periodontal pocket is that former is <3mm in depth and the latter is >3mm. Periodontal pockets usually accompany periodontal disease (gum disease). There is some controversy over the role of periodontal diseases in causing bad breath. However, advanced periodontal disease is a common cause of severe halitosis. People with uncontrolled diabetes are more prone to have multiple gingival and periodontal abscess. Their gums are evident with large pockets, where pus accumulation occurs. This nidus of infection can be a potential source for bad breath. Removal of the subgingival calculus (i.e. tartar or hard plaque) and friable tissue has been shown to improve mouth odour considerably.
Avoiding direct contact with contaminated surfaces such as communal changing rooms and shower floors and benches, avoiding sharing of shoes and socks and avoiding contact with warts on other parts of the body and on the bodies of others may help reduce the spread of infection. Infection is less common among adults than children.As all warts are contagious, precautions should be taken to avoid spreading them. Recommendations include:

Cover them with an adhesive bandage while swimming
Wear latex swimming socks
Wear flip-flops when using communal showers
Do not share towels.Plantar warts are not prevented by inoculation with HPV vaccines because the warts are caused by different strains of HPV. Gardasil protects against strains 6, 11, 16, and 18, and Cervarix protects against 16 and 18, whereas plantar warts are caused by strains 1, 2, 4, and 63. Treatment
A number of treatments have been found to be effective. A 2012 review of different treatments for skin warts in otherwise healthy people concluded modest benefit from salicylic acid, and cryotherapy appears similar to salicylic acid. Medications
Salicylic acid, the treatment of warts by keratolysis, involves the peeling away of dead surface skin cells with keratolytic chemicals such as salicylic acid or trichloroacetic acid. These are available in over-the-counter products, or in higher concentrations, may need to be prescribed by a physician.