Here.  I actually talked with philosopher David Killoren (Australian Catholic U) about these issues, a bit more in the abstract, quite some time ago (and not with reference to providing help for victims of malaria!). (This episode is mainly hosted by Killoren and his philosophy colleague Richard Rowland at ACU.)  Philosophers featured include Peter Singer, Kimberly Brownlee, Jeff Sebo, and Candice Delmas, among others.  One nice thing that comes out in the interview is that Singer thinks there's no alternative to capitalism!  There are also, alas, unexplored assumptions about "harm" that play a role in Killoren's arguments towards the end.