From Online Threat Alerts:
Beware of deceitful Facebook users who are posting pictures of sick, starving, dead and injured children, adults or animals on Facebook, to trick other Facebook users into commenting on them by typing “Amen,” in order to make them popular. This type of activity is another Like-Farming scam. The heartless and deceitful people who are tricking Facebook users into typing “Amen” are only taking advantage of caring Facebook users, who think they are helping out, by playing with their consciences. The scam may also ask Facebook users to compliment a child, an adult or an animal, or type “Amen” to be grateful for something.