An anti-Covid drug widely used across the world may have caused mutations in the virus, researchers said Monday, but there was no evidence that the changes had led to more dangerous variants. Merck's antiviral pill molnupiravir was one of the earliest treatments used during the pandemic to prevent Covid from becoming more severe. The drug works by creating mutations in the virus with the goal of weakening and killing it. However, a new UK-led study has shown that molnupiravir "can give rise to significantly mutated viruses which remain viable."

WHICH COUNTRIES PRESCRIBED THE MOST MOLNUPIRAVIR 

Republican and Democratic leaders in the U.S. Congress spent Monday discussing alternatives to avoid the first government shutdown since 2018. Lawmakers have until midnight Saturday to pass legislation to fund government activities in the next fiscal year, or several federal branches will have no money to continue operating. It could mean furloughs in Social Security, no paychecks for millions of federal workers and impacts such as closed parks and even flight delays.

SEE WHAT A SHUTDOWN WOULD MEAN FOR US GOVERNMENT

Ukraine has received US Abrams battle tanks, President Volodymyr Zelensky said Monday, boosting Kyiv's forces as they seek to break through heavily-fortified Russian defensive lines. The announcement came just after Ukraine claimed it had killed the commander of Russia's Black Sea fleet in a missile strike on Moscow's naval headquarters in Crimea last week in what would be a major embarrassment for Russia.

ABRAMS TANKS COULD BE A GAME-CHANGER FOR UKRAINE

Who is the M1A2 Abrams tank named after, and what is he known for?

Monday's answer: The Red Sea is considered the northernmost tropical sea in the world because the Tropic of Cancer intersects its waters.