It is recorded in the medical litrature that certain types of parasites that comes through eating (infected food) are much less likely to give parasite infection when person at same time as meal was drinking a few glasses of wine.
Most likely because the alcohol weakened or even killed of the parasites that otherwise would invade the intestinal system.
I do not remember what parasite this was, but I remember I was reading it in serious medical book or journal somewhere.
And it make sense also.
Several studies also show people drinking no alcohol have shorter life span than people drinking moderate. But there could be many reasons for this.
Also heavy drinking gives shortest life span (compared to moderate and no alcohol)
In some countries it is tradition to drink wine with the food, this make some sense as the alcohol will be able to reduce live bacterias and some parasites in the food.
When parasites first have got access to the body I would think the alcohol consentratrations (even if you got drunk) in the body would be too small to kill most infections.