There is a series on "The Animal Planet" television network titled "The Monsters Inside Me" which focuses on various parasites that invade and feed off the human body. The program vividly dramatizes the horrible experiences of people who have been infected by some of these organisms. Yet according to theists, as destructive as these forms of life might be, they were created by God who has a purpose for everything that he does. Following this line of reasoning, if they were made by God, as were other other noxious beings whose very existence is a threat to humankind, from cancer cells cells to eye worms (the latter have no other way of survival but by eating the eyes of living humans) we should not question their existence. In fact carrying the logic a step further, man should not attempt to exterminate them as this runs counter to God's will in having created them in the first place.
One Christian viewpoint is that these disagreeable creatures were not always dangerous but became so as the result of original sin(!). Because Adam and Eve disobeyed God and caused Man's fall, people including infants, especially those in remote corners of the world must be made to suffer from horrible diseases and parasites because they have not received God's grace (by accepting Jesus) as their savior. One would think that God would find a faster way to send them the message than by making them wait for missionaries.
In the more advanced cultures, humankind has effectively eradicated many destructive diseases. But in certain cases, some bacteria, such as streptococcus that were hardy enough to withstand antibiotics have mutated into new strains--"superbugs" that are resistant to treatment. One such germ is the flesh-eating bacteria, which was once rare but has become increasingly common.
Well, maybe there's some logic to God's allowing these creatures to endanger people, given his track record. Even in the Torah which does not embrace the doctrine of original sin, he does some pretty nasty stuff when people offend him. For example, most of us know the biblical tale of the great Flood in which God destroyed almost all life on Earth (an act which I call biocide). In fact since life began, most species have not survived the cut. God creates them then destroys them--giving and taking away carried to its ultimate conclusion. He seems to have an acute case of attention deficit syndrome.
However, if we re-frame the discussion regarding the existence of parasites, superbugs, and other dangerous critters (well, dangerous to Man anyway) in the context of natural selection and remove an arbitrary supreme being from the mix, then it all begins to make sense in a way that a creationist /theistic explanation could never begin to. This is why for example I find it hard to understand how those medical professionals who believe in literal interpretation of the scriptures over the theory of evolution can reconcile their scientific training with their creationist convictions regarding the mutant strains of germs which become resistant to antibiotic treatment. The only method that I can see for their coping with this contradiction is compartmentalization. But even so the cognitive dissonance must be a strain.
It's easy to see why parasitic infections and other pest related illnesess are common in poor and backward areas of the world where people are uneducated and lack awareness of basic hygiene, let alone science. Yet if Christian fundamentalists continue to undermine the teaching of theory of evolution in American schools and instead allow creationist doctrine is allowed to prevail, the gains that science has made made in understanding and eradicating these diseases in the U.S. could be seriously affected. We've already seen what happens when the Republican Party, the political arm of the religious right runs the show. During the Bush years, funding for the enforcement of food safety laws was drastically cut, and the incidence of microbe related food borne illnesses and deaths in the U.S. soared. In that era the conservative Republicans' contempt for conducting scientific studies in other health related issues also manifested itself in their fight against stem cell research.
Right-wing fundamentalists' domination of social-political values must be stopped. Failure to end their anti-life policies is hazardous to America's health.