What is the greatest limitations that scientific are dealing with as they try to figure out how to experiment with the ebola vaccine

Ithink the answer is talking about their problems  

1.)dr. natterson- horowitz came to realize that their isn't much of a difference between animals and humans. just like humans, animals can suffer from illnesses and diseases like breast cancer, self injury, anxiety, and many more. she also discovered how they even treated and performed surgical procedures on animals just as if the animal it self were human. the los angeles zoo called dr. natterson- horowitz because they knew that she was a doctor and that  she would be able to recognize what was wrong with the gorilla. they knew that humans and gorillas were similar, so instead of calling another veterinarian, they called a doctor.

Some of their responsibilities are to evaluate safety, efficiency, and effectiveness of the biomedical equipment. train people on how to properly operate biomedical equipment. lastly is to research the engineering aspects of the biological systems of humans and animals.