Perhaps you should try some spelling variations:
"decrease pathogenic load" » "decrease pathogens load" (Expand Search), "decrease pathogenesis load" (Expand Search), "decrease pathogenic lead" (Expand Search), "decrease pathogensic load" (Expand Search)
"decreased pathogen load" » "decreased pathogen lead" (Expand Search), "decreased pathogens load" (Expand Search)
"increase pathogen load" » "increase pathogen lead" (Expand Search), "increase pathogens load" (Expand Search)

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You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("decrease pathogenic load") OR ("decreased pathogen load"))) OR ("increase pathogen load"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"decrease pathogenic load\") OR (\"decreased pathogen load\"))) OR (\"increase pathogen load\"))".
• Removing quotes may allow a broader search: (((( decrease pathogenic load ) OR ( decreased pathogen load ))) OR ( increase pathogen load )).
• Adding a wildcard symbol may retrieve word variants: (((("decrease pathogenic load") OR ("decreased pathogen load"))) OR ("increase pathogen load"))*.