Definition: In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.
Input: Article: Viruses come in an enormous number of shapes and forms.As we begin to understand them more,the hope is we might be able to control them better, says Carl Zimmer.And who knows,the day might come when we can treat them as friends not enemies. Science writer Carl Zimmer says that in his utopia there would be a global public health system with sophisticated drugs and vaccines to deal with any virus that could cause us trouble. Viruses are by far the most abundant life form on Earth.If you took all the stars in the universe and multiplied that number by a million,that's how many viruses we think are on the planet.     Zimmer thinks we should face the future with a mixture of optimism and preparing for the worse.He thinks we will face some unknown virus that will cause a lot of damage-history tells us that this is so.We do understand viruses a lot better now, and there is great hope that one day we'll be able to find a drug that c. an kill any virus.But this research is at a very preliminary stage,and it will be a number of years before we see whether this type of universal anti--viral drug could actually work. Viruses are very versatile and clever, and so there are things that they can do for us.Some scientists are using viruses as engineers to assemble solar panels, others are using viruses to manufacture proteins that could be used as drugs.So,maybe in the future we won't think of viruses as our enemies,but instead view them as our friends. 
 Answer: complicated drugs and vaccines could be traded among countries
