Question

Why are vaccines not typically tested on fungi and plants before being tested on animals and humans, even though fungi and plants are closer to humans on the evolutionary tree than animals such as chimpanzees? Additionally, some fungi are known to be susceptible to human illnesses and can even sneeze.

Answer 1

Vaccines are tested on animals rather than fungi or plants due to physiological and immunological differences; fungi are eukaryotic like humans, making treatment development challenging without affecting the host.

Step-by-step explanation:

Vaccines are not typically tested on fungi and plants before being tested on animals and humans because these organisms have very different physiological and immunological responses to pathogens when compared to humans. Although fungi do share certain evolutionary traits with animals, such as their cell walls made of chitin and the storage of carbohydrates as glycogen, they are heterotrophic and cannot perform photosynthesis unlike plants. Fungal infections are challenging to treat because they are eukaryotic, just like human cells, which makes it difficult to develop drugs that target them without also affecting the host. Vaccines need to be tested on systems that closely mimic the human biological and immune response to ensure safety and efficacy. This is why animal models, which are physiologically more similar to humans than fungi or plants, are used for vaccine testing.