Risk factors for Buruli ulcer disease (Mycobacterium ulcerans Infection): results from a case-control study in Ghana.
BACKGROUND
Morbidity due to Buruli ulcer disease (BUD), a cutaneous infection caused by Mycobacterium ulcerans, has been increasingly recognized in rural West Africa. The source and mode of transmission remain unknown.


METHODS
To identify BUD risk factors, we conducted a case-control study in 3 BUD-endemic districts in Ghana. We enrolled case patients with clinically diagnosed BUD and obtained skin biopsy specimens. M. ulcerans infection was confirmed by at least 1 of the following diagnostic methods: histopathologic analysis, culture, polymerase chain reaction, and Ziehl-Neelsen staining of a lesion smear. We compared characteristics of case patients with confirmed BUD with those of age- and community-matched control subjects using conditional logistic regression analysis.


RESULTS
Among 121 case patients with confirmed BUD, leg lesions (49%) or arm lesions (36%) were common. Male case patients were significantly more likely than female case patients to have lesions on the trunk (25% vs. 6%; P = .009). Multivariable modeling among 116 matched case-control pairs identified wading in a river as a risk factor for BUD (odds ratio [OR], 2.69; 95% confidence interval [CI], 1.27-5.68; P = .0096). Wearing a shirt while farming (OR, 0.27; 95% CI, 0.11-0.70; P = .0071), sharing indoor living space with livestock (OR, 0.36; 95% CI, 0.15-0.86; P = .022), and bathing with toilet soap (OR, 0.41; 95% CI, 0.19-0.90; P = .026) appeared to be protective. BUD was not significantly associated with penetrating injuries (P = .14), insect bites near water bodies (P = .84), bacille Calmette-Guerin vaccination (P = .33), or human immunodeficiency virus infection (P = .99).


CONCLUSIONS
BUD is an environmentally acquired infection strongly associated with exposure to river areas. Exposed skin may facilitate transmission. Until transmission is better defined, control strategies in BUD-endemic areas could include covering exposed skin.
Raghunathan
Pratima L
PL
National Center for Infectious Diseases, Division of Applied Public Health Training, Epidemiology Program Office, Centers for Disease Control and Prevention, Atlanta, GA, 30333, USA. pgr4@cdc.gov.
Whitney
Ellen A S
EA
Asamoa
Kwame
K
Stienstra
Ymkje
Y
Taylor
Thomas H
TH
Amofah
George K
GK
Ofori-Adjei
David
D
Dobos
Karen
K
Guarner
Jeannette
J
Martin
Stacey
S
Pathak
Sonal
S
Klutse
Erasmus
E
Etuaful
Samuel
S
van der Graaf
Winette T A
WT
van der Werf
Tjip S
TS
King
C H
CH
Tappero
Jordan W
JW
Ashford
David A
DA
D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D005869:Ghana / Q000453:epidemiology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009165:Mycobacterium Infections, Nontuberculous / Q000453:epidemiology* / Q000382:microbiology*; D019911:Mycobacterium ulcerans / Q000302:isolation & purification*; D016017:Odds Ratio; D012307:Risk Factors; D012727:Sex Characteristics; D012883:Skin Ulcer / Q000453:epidemiology / Q000382:microbiology*