Computational Biology Group, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa. cathal@science.uct.ac.za|Computational Biology Group, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa. cathal@science.uct.ac.za|Computational Biology Group, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa. cathal@science.uct.ac.za