Can swarming locusts act as a vector for any human pathogens?
I have not heard of locusts being a vector for any pathogen. For immunocompromised people, they can on rare occasions be infected by bacteria carried in the guts of insects. For desert locusts, their main gut bacteria is Pantoea agglomerans (Enterococcus agglomerans). This species has been listed as a pathogen of immunocompromised patients.