Vivian - one way to prevent smell from entering the clothes is using Swiffspray. Just google it  It has two spray components one of them is silver. You need to  need spray both components one after the other or together. The order of spraying does not matter. This can be used  on pure cotton clothes and spray on underarm path of your shirt(spray inside out). You may need 10 sprays on each side. This should reduce smell at least for 5 washes. Also while washing the shirt do not add any stain remover. It is costly though