7th Call - Dr. Phyllis Gertrude Adokailey Addo

Project Title: Acanthamoeba species as a Natural Vector for the Transmission of Buruli Ulcer (BU): Proof of Principle.

Principal Investigator: Dr. Phyllis Gertrude Adokailey Addo (Department of Animal Experimentation, NMIMR)

Email Address: naddo@noguchi.mimcom.org

Award Amount: GHC 24,991.00

Project Status: On-going

Summary:

Buruli ulcer (BU) remains the third most prevalent mycobacterial disease after tuberculosis and leprosy. It is caused by Mycobacterium ulcerans. The mode of transmission is not known. Wilson et al (2011) have posited that Acanthamoeba species could be a natural vector in Buruli ulcer transmission and we have recently shown that Acanthamoeba polyphaga could harbour M. ulcerans 1615::RFP for a period of 41 days during co-culture. Based on the observation that: (1) some amoeba-resistant bacteria become virulent when primed in amoeba; (2) that there is an emerging positive biological gradient between endemicity of BU and abundance of free living amoeba (FLA) and that (3) Acanthamoeba spp cause skin dermatitis, this study hypothesizes that A. polyphaga can transmit M. ulcerans to mammalian host through cuts or abrasions on the skin. The overall objectives of study therefore are to test the supposition that trophozoites of A. polyphaga containing M. ulcerans can transmit M. ulcerans through cuts and thus cause BU in a mouse model and also that amoeba-primed M. ulcerans will cause BU lesions at an earlier time than broth-grown M. ulcerans. The results obtained would provide information to fill in this important gap in knowledge about the transmission of BU to human host. It will also put the transmission route into perspective and establish the role of A. polyphaga in the ecology and transmission of M. ulcerans.