I will preface with saying that I think a Vet needs to have a look at your pup and figure out the best course of action
I am not one for home remedies and such but we had a similar thing happen to our dog a couple of years ago and it just happened to be at a time when the HWYS were closed, freak snow-storm, nobody was allowed on the roads, businesses closed, basically a state of complete standstill for about 5 days throughout our area. So needless to say, I had to make due with what I had on hand.....I don't recommend trying to take care of this yourself. It could be similar to what my Munchkin had (still not certain what it was) or it could be something totally different....so if you can, please seek medical attention ASAP! ~
What I did was gently shave the neck area, cleaned the wounds with hydrogen peroxide 3% several times a day, inbetween applying polysporin and zinc oxide ointment (it was all I had) I made sure to not let her lick it and tried to keep her scratching to a minimun. Gave her benedryl and probiotics/prebiotics and kept a close eye on her. For the most part, I kept the neck uncovered to allow the air to circulate and I kept her away from the other dogs, because I didn't know if it would spread. I also resisted the urge to pick off the dried scabs until about the 5th day. Again, probably not recommended but they were just hanging there by then anyway. It was a long week,
I'll tell ya!
She did very well though and by the time we were able to travel on the HWY again, the sores were almost completely gone, the Vet said that nothing needed to be done at that point, so I was very relieved that we were able to stop the spreading, help with the discomfort and actually aid in the healing process. Your little one may need antibiotics tho.
Our Vet thinks she may have been bitten by a weasel as we had a few who hung out in the woodpile but I cant imagine that being the case with 6 feet of snow and all their time outside was supervised. I have wondered if it was infact some kind of fungal / yeast infection, or ringworm or a localized mange but I guess I will never know...my dogs have never even seen a flea and have not suffered anything even remotely similar since....so I just don't know?
This did happen shortly after she was given her yearly vaccination, which is another reason I no longer believe in overvaccinating dogs when simple tests (titer) can show if they are still protected or not.
Has he been vaccinated lately?
Was he under any kind of added stress before this occured?
Any chronic coughing?
Does he have an underactive thyroid?
Is the affected area smelly?
I know every dog and owner are different but I personally don't have much faith in flea shampoos and I also think bathing a dog weekly is a bit excessive.
Have you considered a topical flea treatment instead? Not that I would recommend applying now, with his current condition. Do they have such topical treatments available in Borneo? Something like Advantix not only kills fleas and ticks but also repel bitting flies and mosquitos....Might be something to look into, after you get this under control
Sorry for the long post - I tend to babble when I haven't had enough sleep
I hope you're able to bring him into the Vet
Please let us know how it unfolds....I'm very curious as the sores are so similar to what my pup had years ago.
Best of Luck