How to prevent Fowl pox from affecting your flock of birds

Dennis Kigen has a flock of 148 birds of mixed ages in his farm in Kiserian. He got the stock to start his farm from this home village early last year. Last week, he started observing dark pimples on the unfeathered parts of the body of the eight-week-old chicks and yellow lesions in the mouth and blindness among the growers which are about 4 months old. He has never had his flock vaccinated. He was worried about this condition and called me.