Africa is the world’s second-largest and second-most-populous continent. At about 30.3 million km2 including adjacent islands, it covers 6% of Earth’s total surface area and 20.4% of its total land area. With 1.2 billion people as of 2016, it accounts for about 16% of the world’s human population. The continent is surrounded by the Mediterranean Sea to the north, both the Suez Canal and the Red Sea along the Sinai Peninsula to the northeast, the Indian Ocean to the southeast and the Atlantic Ocean to the west.
Asia is largest and most populous continent in the world and it is located primarily in the Eastern and Northern Hemispheres. It shares the continental landmass of Eurasia with the continent of Europe and the continental landmass of Afro-Eurasia with both Europe and Africa. Asia covers an area of 44,579,000 square kilometers, about 30% of Earth’s total land area and 8.7% of the Earth’s total surface area.
Now, Are Africa and Asia Connected By Land?
According to wiki, a continent is a large landmass while an island has to be land surrounded by water, but by convention and in practice most major islands are associated with a continent.
Though, Africa and Asia were connected prior to the construction of the Suez Canal in November, 1869, sharing the continental landmass of Afro-Eurasia with both Europe and Africa. But, Afro-Eurasia latter divided into Africa and Eurasia (which can be further subdivided into Asia and Europe).
The Suez Canal happens to traverse the isthmus between the Mediterranean Sea and Red Sea, dividing Asia and Africa.
And going by this, Africa and Asia are no longer connected by land due to the Suez Canal, because both continents are too big to be considered an island.