ויקרא, פרק י״ג, פסוק מ״ג

When leprosy appears on a bald spot at the front or back of the head, it creates a unique situation that bridges the gap between afflictions on hairy areas and those on normal skin. Despite the loss of hair, this bare area maintains the exact same legal status as regular body skin. The priest examines it using the standard criteria applied to the rest of the body. Although baldness is primarily common among men, these regulations apply equally to women who experience hair loss [רלב״ג].

The affliction often takes the form of a swelling, with the disease located directly within it [ביאור יש״ר]. Swellings are specifically highlighted because they are the most frequent type of mark to appear on this part of the head, but the same rules apply to other forms of the disease, such as bright spots or scabs [מלבי״ם]. The mark may appear in a mixed reddish-white shade. While earlier rules only associated this mixed color with bright spots, this case reveals that a swelling can also appear in this blended hue [העמק דבר].

The primary approach among commentators is that the laws for a bald spot are directly compared to those of regular skin leprosy [אבן עזרא, בכור שור, שטיינזלץ]. Consequently, the mark is only considered impure if it matches one of the four specific shades of white. This stands in sharp contrast to leprosy on a hairy head, where the color of the mark is completely irrelevant [רש״י, משכיל לדוד, ביאור יש״ר, רש ר הירש]. Furthermore, the disease must cover a minimum area, specifically the size of a bean, to be considered significant [מלבי״ם].

The requirement for a thorough visual examination by the priest dictates a quarantine period identical to that of normal leprosy, which can last up to two weeks. If no clear signs of impurity develop after the first week, the priest isolates the person for a second week. This differs from afflictions like boils or burns, which are strictly limited to a single week of quarantine [רש״י, תורה תמימה, מלבי״ם]. However, because the area is entirely hairless, the standard impurity sign of hair turning white is physically impossible. As a result, the mark can only be declared fully impure through two specific developments: the spreading of the disease across the skin, or the appearance of healthy flesh within the mark itself. Because the bald spot lacks the potential for white hair, one might mistakenly assume it should be treated more leniently, perhaps requiring only a one-week quarantine like a boil. To prevent this misunderstanding, the rules explicitly equate the bald spot to regular body leprosy [רלב״ג, העמק דבר, רש ר הירש, מלבי״ם].