Why has God allowed us to discover vaccines and antibiotics if He wanted to use disease to punish us?

Question:  Why God has allowed the discovery of vaccines and antibiotics to cure illness? If diseases are punishment from God then if we cure them we go against the will of God who wants to punish us. If vaccines and antibiotics are discovered because God wants to bless us why did God contradict Himself by sending diseases and then sending the cures of the same diseases he has sent? And if vaccines and antibiotics are a blessing from God why has God delivered these blessing after millions of people are already dead?

Answer:  I am reading a science fiction book called The Final Enemy by Dan Petrosini.  The plot is that a meteor falls to earth in the U.S. and it is discovered that wherever the meteorite goes natural deaths stop occurring.  After much testing the government sends the meteorite on a tour of the United States and then eventually all countries that sign a treaty with the United States and natural deaths basically cease around the world.  But with that comes other problems.  Overpopulation is the main problem, it seems, causing a major food shortage that threatens the entire world.  But the other problem is the ceasing of religious observance.  People don’t need God anymore, or so they think.

In Genesis 3, after Adam and Eve sin, God imposes what I’ll call “futilities” upon mankind.  In birth the woman’s pain will be greatly increased.  What should be an unadulterated experience of joy and meaning will be fraught with pain and suffering.  For the man, the work he does and must do to grow food will be met with plants or weeds that will threaten to choke out what it is edible and make his work frustrating.
God is not telling Adam and Eve or us that we shouldn’t seek to deal with the pain of childbirth or just let the weeds grow.  On the contrary, we will need to fight against these futilities but there will be that futile or useless aspect to them because we will never be able to completely eliminate them.  This level of frustration, however, is essential to our well-being.  God prohibits Adam and Eve from eating from the tree of life and living forever.  Paul says (Romans 8:18-21) that God purposely subjected the world to futility in hope of its future redemption.
Mankind’s greatest temptation is to seek life and peace and joy apart from God and in what He created for us, the world.  And without a doubt there is much the world offers that seems to bid us find our life/joy/peace in it (beauty, relationships, accomplishments) except that this frustrating aspect to life, the futility of it, keeps us from fully finding life there.  And this is a blessing, because were the world to work the way God made it to work originally, if we didn’t die (the ultimate futility) and if our efforts were always rewarded with success and our relationships work out the way we wanted, etc., we would be tempted to think that we were fine without God.  But we are not fine without Him.  We desperately need Him.  Futility built into the system helps us see that.
So God’s purpose in bringing illness and death and frustration and weeds and pain, is not entirely a punishment, as you characterized it, but a necessary consequence of trying to find life apart from Him, as Adam and Eve did and as every subsequent generation has.  These frustrating aspects to life are actually a mercy, helping us move toward Him and find the true source of our life/joy/peace.
He has also made us in His image and that makes us creators and innovators and doers and workers.  We are made to overcome problems and so we have developed ways to kill weeds and minimize pain and overcome illnesses, and yet each of these has also brought with them frustrating problems.  Weed killers poison our foods, pain relievers can become addictive or affect the child in the womb, and antibiotics can serve to strengthen the very bacteria they were meant to destroy resulting in super bugs that are not responsive to antibiotics.  We are not to quit seeking solutions, but we are reminded again and again that the ultimate solution is not in our intellect or abilities but in God and a relationship to Him.