Persons most commonly affected: Congenital syphilis -- newborn babies of both sexes. Acquired syphilis -- persons of either sex who have had sexual contact with infected persons.

Organ or part of body involved: Reproduction organs, central nervous system, skin and other organs.

Symptoms and indications: Primary stage -- bacteria enters the body through the mucous membranes of the genital organs, rectum or mouth. After a few days or weeks, a small ulcer develops at the site of infection. This may be inflamed, or painless and relatively insignificant, but is highly infectious, and is called the primary sore. Within a short time, the lymph nodes enlarge and harden and this stage lasts for several weeks. The ulcer eventually heals and the swelling subsides. Secondary stage -- symptoms appear about 2 months after infection and include fever, pain, loss of appetite and a red rash that is usually noticed on the chest. The bacteria are found in enormous numbers in the spots of this rash and so this stage is also highly contagious. Third stage -- the final stage may not appear until many months or years after infection, and symptoms are more likely to occur in untreated or inadequately treated persons. In this stage numerous tumour-like masses, called gummas, form and may occur in the skin or within the muscles, bones, brain, spinal cord, heart, liver, stomach, etc. The serious damage that can be caused to tissues and organs may result in blindness, paralysis, tabes dorsalis and mental disability. Also, there may be heart and artery disease. In congenital syphilis, the child is highly infectious and a few weeks after birth, develops second-stage symptoms of the disease.

Causes and risk factors: Is the bacterium Treponema pallidum, which is spread by direct sexual contact with an affected individual and to offsprings from infected mothers.

Prevention: Can be prevented by avoiding sexual contact with someone who has the disease. Because the chance of contracting this and other venereal disease increases with the number of sexual partners, limiting the number of partners is the first step in prevention. Using condoms helps to reduce the risk of contracting syphilis.