![]() ![]() Epidemiologyįrom a global perspective, the nonvenereal treponematoses constitute a significant cause of morbidity in many developing countries. The phylogenetic relationship between different sub-species of treponemes is not clear, as very few isolates of the non-venereal subspecies are available ( Table 1). pallidum pertenue differs by only 0.2% from that of T. Whole-genome sequencing has demonstrated that the genome of T. The four pathogenic treponemes are morphologically and serologically indistinguishable, and share at least 99% DNA sequence homology. They are rapidly killed by drying, oxygen exposure or heating, and cannot survive outside the mammalian host ( 24). They divide slowly (every 30 hours), have a characteristic corkscrew like motility, and can move through gel-like environments such as connective tissue. Treponemes are gram-negative spirochetes which cannot be cultured in vitro. pallidum, the endemic treponematoses are not sexually transmitted. Unlike syphilis, which is caused by the almost identical T. Recognizing that international associations are generally confronting world problems and developing action strategies based on particular values, the initial content was based on the descriptions, aims, titles and profiles of international associations.The endemic treponematoses include yaws ( Treponema pallidum subsp. UIA’s decades of collected data on the enormous variety of association life provided a broad initial perspective on the myriad problems of humanity. The initial content for the Encyclopedia was seeded from UIA’s Yearbook of International Organizations. By concentrating on these links and relationships, the Encyclopedia is uniquely positioned to bring focus to the complex and expansive sphere of global issues and their interconnected nature. These connections are based on a range of relationships such as broader and narrower scope, aggravation, relatedness and more. It is currently published as a searchable online platform with profiles of world problems, action strategies, and human values that are interlinked in novel and innovative ways. The Encyclopedia of World Problems and Human Potential is a unique, experimental research work of the Union of International Associations. Although one of the first descriptions of the disease was made in 1679 by Willem Piso, archaeological evidence suggests that yaws may have been present among human ancestors as far back as 1.6 million years ago. ![]() In 2016, the number of reported cases was 59,000. In 1995, the number of people infected was estimated at more than 500,000. Since then, cases have increased, but with renewed efforts to globally eradicate the disease by 2020. Efforts in the 1950s and 1960s by the World Health Organization decreased the number of cases by 95%. The disease only infects humans, although 18th century French historian Pierre François Xavier de Charlevoix describes it as a disease among geese in the Antilles. Almost 85% of infections occurred in three countries-Ghana, Papua New Guinea, and Solomon Islands. Yaws is common in at least 13 tropical countries as of 2012. Without treatment, physical deformities occur in 10% of cases. Treatment is typically with antibiotics, including: azithromycin by mouth or benzathine penicillin by injection. Improving cleanliness and sanitation also decreases spread. Where the disease is common, treating the entire community is effective. ![]() Prevention is, in part, done by curing those who have the disease, thereby decreasing the risk of transmission. Polymerase chain reaction is the most accurate method of diagnosis. Blood antibody tests may be useful, but cannot separate previous from current infections. Yaws is often diagnosed by the appearance of the lesions. Other related treponemal diseases are bejel (T. ![]() The disease is most common among children, who spread it by playing together. The contact is usually of a nonsexual nature. Yaws is spread by direct contact with the fluid from a lesion of an infected person. After 5 years or more, large areas of skin may die, leaving scars. The bones (especially those of the nose) may become misshapen. The skin of the palms of the hands and the soles of the feet may become thick and break open. After weeks to years, joints and bones may become painful, fatigue may develop, and new skin lesions may appear. This initial skin lesion typically heals after 3–6 months. The center may break open and form an ulcer. The disease begins with a round, hard swelling of the skin, 2 to 5 cm (0.79 to 1.97 in) in diameter. Yaws is a tropical infection of the skin, bones, and joints caused by the spirochete bacterium Treponema pallidum pertenue. ![]()
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