An elderly Kenyan fisherman who was his family's sole provider has forgotten how to fish after developing Alzheimer's disease.
His story is similar to that of an elderly woman who used to collect seaweed for her village. She has now forgotten how to "wade" in the water.
Both are from Mkwiro island along Kenya's coast. They now depend on their families for their livelihood.
BBC photographer Leah Beach shared photos of the two elders, whose names have been withheld, to highlight their plight.
Alzheimer's disease is the most common form of dementia that causes sufferers to lose their memory. It affects people of all ages, but most commonly older people.
The Alzheimer's Society says more than 45 million people around the world have the condition.
The elderly woman's case was profiled as part of events to mark World Alzheimer's Day on September 21.