No good assignment

I’ve just been into to see the academic advisor at uni as I wanted someone to look over my literature review before I handed it in. I came out thinking of what he told me. It was about one sentence specifically. He basically told me that it was crap. I believe that his actual words were that it was no good. The sentence is below:

“Military equipment may have played a major part in increasing the range of the vector mosquito, inadvertently providing receptacles for rainwater in which Aedes aegypti mosquitoes laid their eggs. This equipment was then moved across Asia and the Pacific. Soldiers too were moved across the region and the dengue virus continued to spread. These two factors combined to not only increase the range that dengue fever was able to spread but also provided the means through which the vectors could travel”

I thought that was a bit harsh, especially when I thought that the sentence added to the paragraph. While I wanted to know if my review was okay I guess I was hoping for more constructive criticism. Instead he said the particular sentence was useless. Apart from that all he said was there needs to be more references even if that means on every single line instead of just at the start or end of the paraphrased section. He obviously thought that he had been too harsh as when I was leaving he said that the assignment was very good three times before I left. Good but no good. Now that's confusing!