Related Clues:

• Parasite's need
• Ball thrower
• Big number
• Party throwing a party
• "And now a word from our __"
• Vaccine supplement
• Back financially
• Leno or DeGeneres, e.g.
• Restaurant greeter
• Enthusiastic supporter
• Show runner
• Desk job at 58 & 59-Across?
• One who entertains
• Throw a ball?
• Virus's need