Yaws

YAWS - TROPICAL COMMUNICABLE DISEASE

1. DISEASE PRESENTATION ON YAWS – COMMUNICABLE DISEASE PRESENTED BY, KAVIYA AP RA1522281010017 PHARM D INTERN

2. Yaws is a common disease of children in the tropics. Yaws is a common chronic infectious disease that occurs mainly in warm humid regions such as the tropical areas of Africa, Asia, South and Central Americas, plus the Pacific Islands. It is a chronic, relapsing infectious illness. It first affects the skin and later possibly the bones and joints as well. Yaws is caused by a bacterium, the spirochete  Treponema pertenue . Yaws is promoted by overcrowding and  poor hygiene . Yaws (except for tertiary yaws) may be cured by a single shot of benzathine  penicillin  or an oral dose of  azithromycin . FACTS - YAWS

3. A chronic bacterial infection that affects the skin, bone and cartilage caused by the spirochete bacterium Treponema pallidum pertenue . It spreads through direct contact with the skin of an infected person. A single, berry-like sore on the skin is the first sign of yaws. Without treatment, sores begin to spread. Yaws may eventually cause disfigurement and disability. The condition is treated with antibiotics. WHAT IS YAWS ?

4. The term  yaws  is thought to be of Caribbean origin. In the language of the Carib Indian people,  yaya  is the word for "a sore." Alternatively, the disease term yaws may have come from Africa where the word  yaw  may have meant "a berry." Because the lesions of yaws look like berries, the disease is also called  frambesia  meaning "raspberry." Other older names for yaws include  granuloma tropicum ,   polypapilloma tropicum , and  thymiosis . Why the disease is called yaws ?

5. SIGNS AND SYMPTOMS The incubation period is 2-6 weeks The prodomal period : Headache Fever Chills Weakness Arthralgia Muscles and joint pains in night time

6. Infections, tumors, and the body's response to trauma or injury can all lead to lumps or bumps that appear to be located on or underneath the skin. Depending upon the cause, skin lumps or bumps may vary in size and be firm or soft to the touch. The overlying skin may be reddened or ulcerated. Skin bumps may or may not be painful or tender, depending upon the cause of the lesions. Secondary yaws occurs weeks to months after the primary infection and typically presents with multiple raised yellow lesions or pain and swelling of long bones and fingers (dactylitis).

7. Yaws begins when  T. pertenue  penetrates the skin at a site where skin was scraped, cut, or otherwise compromised. In most cases,  T. pertenue  is transmitted from person to person. At the entrance site, a painless small lesion, or bump, arises within two to eight weeks and grows. The initial lesion is referred to as the mother yaw. The  lymph nodes  in the area of the mother yaw are often swollen (regional  lymphadenopathy ). When the mother yaw heals, a light-colored  scar  remains. CAUSES

8. Yaws is a member of the treponematoses, diseases caused by spiral bacteria in the genus  Treponema ; besides yaws, the disease include endemic  syphilis  ( bejel ) and pinta . Of these three diseases, yaws is the most common. The disease most often starts as a single lesion that becomes slightly elevated, develops a crust that is shed, leaving a base that resembles the texture of a raspberry or strawberry. This primary lesion is termed the  mother yaw  (also termed  buba ,  buba madre , or  primary frambesioma ). Secondary lesions, termed  daughter yaws , develop in about six to 16 weeks after the primary lesion. Almost all cases of yaws begin in children under 15 years of age, with the peak incidence in 6- to 10-year-old children. The incidence is about the same in males and females. PATHOGENESIS

9. Yaws has four stages: primary, secondary, latent, and tertiary. The primary stage is the appearance of the mother yaw. Patients with yaws develop recurring ("secondary") lesions and more  swollen lymph nodes . This represents the secondary stage. These secondary lesions with  rashes  may be painless like the mother yaw or they may be filled with pus, burst, and form ulcers. The affected child often experiences malaise (feels poorly) and  anorexia  ( loss of appetite ). The latent stage occurs when the disease symptoms abate, although an occasional lesion may occur. In the tertiary stage, yaws can destroy areas of the skin, bones, and joints and deform them with pains in the joints and/or bones. The palms of the hands and soles of the feet tend to become thickened and painful (crab yaws). STAGES OF YAWS

10. RISK FACTORS AGE - Primarily a disease of childhood and adolescense GENDER - M > F IMMUNITY - No natural immunity CLIMATE - Endemic in warm and humid climate SOCIAL FACTORS More common in tribal people Poor personal hygiene Overcrowding Low economic standard of people

11. M ost frequently the diagnosis is made on clinical findings. Laboratory confirmation of the diagnosis is by blood serum tests includes ; RPR or rapid plasma reagent test, VDRL test or  venereal disease  research laboratory test, TPHA or Treponema pallidum hemagglutination test, FTA-ABS or fluorescent treponema antibody absorption The reason that  T. pallidum  serum tests are used is that the spirochetes are so closely related, they have similar antigens on their surfaces so that  T. pallidum  and  T. pertenue  are cross-reactive (detected by the same serological tests). DIAGNOSIS

12. Special (dark-field) examination under the microscope in which technicians can actually see the spirochete bacterium is also used to help diagnose yaws. The lesions (both the mother yaw and the secondary lesions) usually have many  T. pertenue  organisms that can be visualized with dark-field examination of lesion scrapings. Other tests that detect spirochetes such as a silver stain or electron microscopy are used mainly by research scientists.  PCR tests can confirm yaws by detecting genetic material from organisms in samples from skin lesions.

13. Treatment of yaws is simple and highly effective.  Penicillin G benzathine  given IM (intramuscularly) can cure the disease in the primary, secondary, and usually in the latent phase.  Penicillin V   can be given orally for about seven to 10 days, but this route is less reliable than direct injection. Anyone  allergic  to penicillin can be treated with another antibiotic, usually  erythromycin ,  doxycycline , or  tetracycline . Azithromycin (in a single oral dose of 30 mg/kg or the maximum 2 g) is the choice that the World Health Organization (WHO) recommends because of the ease of administration. TREATMENT

14. Benzathine penicillin (single intramuscular dose) at 0.6 million units (children aged under 10 years) and 1.2 million units (people aged over 10 years) can be used for patients with suspected clinical treatment failure after azithromycin, or patients who cannot be treated with azithromycin. Patients should be re-examined 4 weeks after antibiotic treatment. Complete clinical healing will be observed in over 95% of cases. Any individual with presumed treatment failure requires macrolide resistance testing.

15. The prognosis of yaws depends upon effective treatment so that the patient will not develop complications. If appropriate treatment of yaws takes place before tertiary yaws develops, the prognosis for a possible cure with little or no complications is good. However, if tertiary yaws develops, the prognosis is worsened depending upon the severity of complications. PROGNOSIS

16. There is no vaccine available to prevent yaws. However, the WHO has established a yaws eradication strategy also referred to as the Morges strategy by which the organization has established a goal of eradicating yaws by about 2020. Because this disease is spread by person-to-person transfer and has no animal reservoir, the WHO considers this a realistic goal. Currently, for individuals,  prevention  is based on interrupting the transmission of the disease from person to person by practicing good hygiene and by early diagnosis and rapid appropriate treatment with azithromycin to prevent spread in the community. Is YAWS preventable ?