1. Prof.Vipada Chaowagul Medical department, Sunpasitthiprasong Hospital Ubon Ratchathani What’s new in melioidosis ?

2. History 1911- First recorded in the world (Whitmore & Krishnaswami): Glander-like illness, Bacillus whitmore. 1917 - More than 100 cases reported from Rangoon (Krishnaswami): Bacillus pseudomallei 1932 - Stanton and Fletcher named ‘melioidosis’ [Greek] ‘melis’= a distemper of asses, ‘eidos’ = resemblance 1950-75 Vietnam war: Vietnam time-bomb, Pseudomonas pseudomallei 1992 Burkholderia pseudomallei

3. 100 cases among French forces in Indochina (1948-1954) Cases reported from veterans of World War II 343 cases in American soldiers fighting in Vietnam were reported to be melioidosis (1973) Many cases reported from American veterans years after exposure ‘Time-bomb Disease’ Spotniz M. Medical World News 1966; 7:55.

4. Vietnamese time-bomb Photo by Bill Kelly; from http://www.manchu.org/photo/index12.htm

5. Worldwide distribution of melioidosis

6. 1 st reported case: a Russian man who lived in BKK and travelled to Cambodia in 1930 1 st reported of Thai patient in 1955: a policeman with neck abscess 1982: 1 st case found in Sunpasitthiprasong Hospital Ubon Ratchathani (grew Pseudomonas pseudomallei) 1985: >800 cases of definite & probable melioidosis reported at 1 st Annual IDAT meeting. 1992 seven Pseudomonas species were moved to a new genus “Burkholderia” including Burkholderia pseudomallei History of Melioidosis in Thailand

7. Highest incidence of melioidosis: Ubon Ratchathani 21.3 cases/100,000 population Overall incidence in Thailand: 12.7 cases/100,000 population The incidence increase from 8 (in 2000) to 21.3 (in 2006) Male sex predominant 80% adult case, age ranged 40-60 yr 20% paediatrics cases (80% seroconversion by age 4) Major risk factor: known or undiagnosed DM - 80 % of cases occur in rainy season 3 rd most common cause of death among infectious diseases in Northeast Thailand (after HIV and tuberculosis) Incidence of melioidosis in Thailand

8. Year Melioidosis in Ubon Ratchathani

9. Year Per 100,000 population Melioidosis in Ubon Ratchathani

10. Community-acquired bacteraemia in NE Thailand 1.E. coli (23%) 2.B. pseudomallei (19%) 3.S. aureus (8%)

11. B. pseudomallei – Genus Burkholderia >40 species B. thailandensis & B. pseudomallei found in soil in Thailand & Australia Causative bacteria

12. Routes of infection Inhalation Direct inoculation Ingestion

13. Routes of infection (cont.) Related to breast feeding from mothers with mastitis (Australia) Human to human transmission Nosocomial Infection from a suspected environment source Mother to child transmission (Neonatal melioidosis) Laboratory-Acquired Infection

14. Risk factors for melioidosis Diabetes - 23 to 60% Heavy alcohol use – 12 to 39% Chronic pulmonary disease - 12 to 27% Chronic renal disease - 10 to 27% Thalassemia – 7 % Glucocorticoid therapy - < 5 % Cancer - < 5%

15. Clinical presentation Disseminated septicemia Non-disseminated septicemia Localized melioidosis Transient bacteremia Probable melioidosis Subclinical melioidosis

16. Organ involvement  Diseases Nervious system Eye, ENT Skin, soft tissue Lung  pneumonia, lung abscess Liver and spleen Liver and splenic abscesses Genitourinary: prostrate, kidney, scrotum Prostatic, renal, scrotal abscesses Vessels  Mycotic aneurysm Pleura  Empyema thoracis Pericardium  Pericarditis Lymph node  lymphadenitis Adrenal gland, breast  abscess Uterine tube,ovary  tubo-ovarian abscess

17. The clinical presentation of ‘MELIOIDOSIS’ may mimic many diseases esp. ‘TUBERCULOSIS’ The two diseases have overlapping risk profiles and both pathogens are “ intracellular” The host responses to melioidosis and to tuberculosis are similar : Both are dominated by ‘Interferon – Mediated Signaling’ and this similarity means gene expression signatures from whole blood do not distinguish between these two diseases Clinical Melioidosis: The Great Imitator

18. Abscesses Anywhere Every organ Multi-organs Transient bacteremia Septicemia Disseminated septicemic multi-organs involvement (Overall MR.20%) Abscesses Anywhere Every organ Multi-organs Transient bacteremia Septicemia Disseminated septicemic multi-organs involvement (Overall MR.20%)