The charitable organization Oxfam does not generally respond to humanitarian crises in America or other wealthy nations; they primarily provide relief in impoverished or infrastructure-deficient regions of the world.
They are making an exception in the case of the ongoing Puerto Rico crisis, and are pinning the need for such action squarely on the Trump administration's continued lack of action.
Oxfam has monitored the response in Puerto Rico closely, and we are outraged at the slow and inadequate response the US Government has mounted in Puerto Rico. Clean water, food, fuel, electricity, and health care are in desperately short supply and quickly dwindling, and we’re hearing excuses and criticism from the administration instead of a cohesive and compassionate response. The US has more than enough resources to mobilize an emergency response but has failed to do so in a swift and robust manner. Oxfam rarely responds to humanitarian emergencies in the US and other wealthy countries, but as the situation in Puerto Rico worsens and the federal government’s response continues to falter, Oxfam has decided to step in to lend our expertise in dealing with some of the world’s most catastrophic disasters.
Oxfam will work with local leaders to assess the next needed steps, such as "meeting the needs of rural communities who face increasing risks of disease like cholera." The United States government has generally taken it upon itself to ensure its citizens do not die of cholera—or, say, suffer permanent injury from lead-tainted water—but current government actions have convinced the relief organization that the U.S. government can no longer be presumed competent enough to muster the needed response itself.