The recent warming of US-Cuban relations and the fall in international oil prices raise the question of whether Venezuela can put national interests ahead of ideology.
The historic opening between the two countries could have an impact on travel and business in the long-term, though changes are likely to happen gradually.
Cuba had relied on Venezuela to prop up its economy. But with that support uncertain, the Castro brothers appear to have decided to come in from the cold.
Former President Mujica, an ex-guerrilla who was once tortured in jail, agreed to take the prisoners earlier this year. He said he was doing it 'for humanity.'
The US is the biggest financial donor to Ebola-infected countries in West Africa. But the largest number of healthcare workers deployed in the field hail from an island nation with a cash-strapped communist government.
Former President Castro was seen publicly in Cuba for the first time in nine months.