Scientist have discovered a new pathogen named Virus X. This infection causes its victims to suffer from severe diarrhea and is spreading quickly across major cities around the world. During their investigation, these researchers tracked the virus back to a population of pigs in Asia. These animals were not affected by the disease themselves but large numbers of the virus were found in their feces. In particular, when visiting one farm, scientists observed workers routinely going from taking care of the pigs to picking fruits and vegetables without washing their hands. Fruits and vegetables that were contaminated with pig feces would act as a...
portal of entry
reservoir
vector
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