I am interested in your query because I have had wild hog encounters as well. Their snouts are big and massive because they use them for rooting. Not at al sure about how sensitie their sense of smell is or how they would react to a bad odor. Would they flee or attack??
I would suggest you hulk up= do everything to appear as big as possible. You might also try soe sort of noisemaker, perhaps the whistle you undoubtedly carry as a well equipped hiker or even some sort of shocker/taser like device that might stun the pig. Be sure you know the difference between your taser and your firearm.
I dealt with feral pigs on Santa Rosa and Santa Cruz Islands when they became part of Channel Islands National Park. They had robust wild pig populations, which had to go because they were severely impacting native populations. The State of Cal would not allow them to be transported to the mainland because of disease transmission. Generous shots of 270 Winchester solved the problem - that and lots of money.
Fatal encounters with feral hogs are known - at least five since 1825, according to internet sources. i wish I had a definitive answer for you and I have responded only because there has been no other response. I would try a noisemaker of some sort, probably high frequency and shrill....
Its amazing how destructive they are. That’s the first sign they are in the area where they have everything torn up. You can hear them just yards away in the heavy brush. If they charge out you are only going to have seconds to react until they would be on you. They go for your legs with their tusks to get you on the ground then you have big trouble. There is no bulking up with me, I am around 150# wet. Lol. My eyeball to eyeball encounter was just several feet away. After that we always carry spray and a weapon. I would think the spray would be the better option. If I can’t get an answer here maybe I should contact a manufacturer or customer rep. The pixs were taken at Merritt Island Wildlife Refuge near Kennedy Space Center.
Here is a pertinent section from Wikipedia"
Feral pigs can be extremely dangerous to people, particularly when the pigs travel in herds with their young, and should be avoided when possible. Feral pigs living in the United States have been known to attack without provocation and fatally injure human beings. There have been over 100 documented attacks by feral pigs on human beings in the United States between the years 1825 and 2012. Of these attacks, five have been fatal. Three of the five fatal attacks were by feral pigs wounded by hunters. Both male and female feral pigs are known to attack without provocation, and attacks by solitary males, as well as group attacks have been documented.
On November 26, 2019, a 59-year-old Texas woman named Christine Rollins was attacked and killed only a few feet away from the front door of her workplace by a herd of feral pigs in the town of Anahuac, Texas, which is 50 miles east of Houston. This incident was the fifth documented fatal feral pig attack in the United States since 1825. Chambers County Sheriff Brian Hawthorne in a formal statement to news media stated that "multiple hogs" assaulted Rollins during pre-dawn hours between 6 and 6:30 a.m. when it was still dark outside. The victim died of blood loss as a result of her injuries.
You are probably correct. A weapon is probably not the best choice:
Although it is discussed I could not find anything definitive that says bear spray is effective against feral hogs. Actual attacks, like with black bears, seem to be rare in the US although they do occasionally occur.
The general advice is to slowly back away but not run. If they seem aggressive and do not just leave you be, climb a tree or move to higher ground if possible. If attacked, stand ground and try to step aside when charged. Try not to be knocked over since that is their main attack. If knocked over, fight back If you can't fight back, the fetal position with your hands behind your neck is probably the most protective position to assume.
I am dubious of the "fight back" advice. It could make a strong motivated animal more aggressive and it seems these animals like grizzly bears, tend to be somewhat fearless. A cougar will likely be deterred if you fight back since they rely on being uninjured to hunt. But a 600lb pig is built to fend off attackers and unless you disable it completely, attacking it could just get it more riled up. Hard to know.
Many reports of problem hog encounters (mostly in Europe) involve looking for food at campsites so like for bears camp hygiene is the best preventative. Hang or can your food. Don't spread it out unprotected or leave garbage or a mess. Pack out what you pack in but don't consume.
Hogs can apparently be deterred more generally from property by Deer Spray but that apparently makes the area unpalatable so it won't work in an attack. Possibly it could be useful around more permanent camps but probably not useful backpacking.
They can also apparently be deterred by ultrasonic "repellers" because they have very sensitive hearing. Therefore my best guess is that very loud whistles and air horns may be the best thing to deter an imminent attack or discourage camp foragers. I have no personal experience and there is not much anecdotal evidence to back that up. Most discussions I found dissolved into how to cook pig meat.
Just got an email response from a Customer Rep from the #1 brand spray, not to mention any names. Here is how it went...........”No research has been done on the effectiveness of Bear Spray on hogs......However the pepper based spray will cause discomfort when sprayed in the face of any species with eyes, nose, and mouth and will generally turn the animal away”. Guess I’ll take that as a yes.
Experimeents can be so exciting!! Let us know how it goes...hoping for a run away success