这是猫癣吗，猫癣怎么治！！！

[img]https://img.nga.178.com/attachments/mon_202208/25/-7knvQbs0p-hh4vZcT1kShs-124.jpg[/img][img]https://img.nga.178.com/attachments/mon_202208/25/-7knvQbs0p-jxruZcT1kShs-124.jpg[/img][img]https://img.nga.178.com/attachments/mon_202208/25/-7knvQo2kp-c9h6ZbT1kShs-124.jpg[/img][img]https://img.nga.178.com/attachments/mon_202208/25/-7knvQo2kp-3cggZeT1kShs-124.jpg[/img][img]https://img.nga.178.com/attachments/mon_202208/25/-7knvQo2kp-7v1oZfT3cShs-124.jpg[/img][img]https://img.nga.178.com/attachments/mon_202208/25/-7knvQo2kp-f56oZeT1kShs-124.jpg[/img][img]https://img.nga.178.com/attachments/mon_202208/25/-7knvQo2kp-3b93ZfT1kShs-124.jpg[/img][img]https://img.nga.178.com/attachments/mon_202208/25/-7knvQo2kp-ghwkZhT3cShs-124.jpg[/img][img]https://img.nga.178.com/attachments/mon_202208/25/-7knvQo2kp-ayjdZeT1kShs-124.jpg[/img]
家里接老二回来大概两周，今天发现老大长猫癣了，老二还没啥事儿，我和女朋友两个人脖子上好像也长了。
问题一
如果是老二传染的，为什么老二没事儿？
问题二
猫癣如何治疗，需要剃光身上的毛吗？口服药还是外用药 还是打针？(据说口服伤肝)
问题三
今后怎么才能预防？一直都给主子吃好喝好，不应该是免疫力低下 体弱多病猫吧
问题四
其中有一张图片是猫咪肩膀位置，掉毛并且有小黑点，这又是怎么了？