Short answer: No. The Church does not teach that all human persons are descended from Noah and his family. The idea that we must all be descendants of Noah is based on the false assumption that the Noah story is entirely literal. In my opinion, the story of Noah and the Flood contains both literal and figurative elements.
There was a literal flood event, but the extent of the flood is figurative. The flood did not cover the entire surface of the earth. The flood did not kill all human persons, nor all animals.
Noah did build an Ark for his family. There were many animals on the Ark. But the Ark did not contain every species, as it did not need to do so. Many animals survived the flood apart from the Ark. The humans and animals on the Ark were merely representative of all life on earth.
Therefore, after the Flood, there were many human persons on earth who were not descendants of Noah.
For more, see my book: Noah’s Flood: Literal or Figurative?
by
Ronald L. Conte Jr.
Roman Catholic theologian and translator of the Catholic Public Domain Version of the Bible.
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the reproach of Christ 
Is he ark going up a mountain figurative or literal? If there was a local flood like that, how would it be confined to a geographical area?
In my view, the Flood was a global catastrophic event, but did not cover all land with water. The Ark may well have landed on a mountainside. The event was probably a comet striking the deep ocean, as W. Bruce Masse has theorized.
Ron, I think I will have to read your “Noah’s Flood” book to get your full perspective. But, if the flood described in Genesis was actually caused by a comet, can we also say that it was directly caused by God due to the sin of humankind? Jesus himself, and St. Peter in his second epistle make clear that the flood was directly caused by God. The comet theory seems to make it a random event, which was rather attributed to God. I am having trouble reconciling this apparent (to me) discrepancy. Thank you.
The Flood was caused by the providence of God. Nothing in Scripture necessitates the conclusion that the Flood was “directly caused” (miraculously) by God. “He causes his sun to rise upon the good and the bad, and he causes it to rain upon the just and the unjust.” (Mt 5:45).