Many factors: There are many factors, some are 1 peoples resistant to get their children and themselves immunized due to ignorance 2 international travel which brings infectious disease from under developed countries to others 3 new unexpected disease like h1n1 4 over use of antibiotics causing resistant organisms.
Answered 12/14/2016
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A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
4 doctors weighed in across 2 answers
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