It's important to understand that Hepatitis B virus (HBV) can be transmitted through various bodily fluids, including saliva. Many people mistakenly think that only blood or sexual contact pose risks, but perinatal transmission and exposure to infected saliva are significant concerns, especially for newborns. The infection can lead to serious health problems like cirrhosis and liver cancer later in life, making early prevention essential. Newborns are particularly vulnerable because their immune systems are still developing. Pediatricians advocate for vaccination starting at birth or within the first two months to provide early protection against HBV. Aside from parental status, consider the potential exposure from other caregivers such as daycare workers, nursery staff at church, or close family members. It's not always possible to know everyone's infection status, so immunization acts as the best defense. Needle exposure is another common transmission route, as indicated in global endemic areas. Preventing transmission through multiple routes—including blood, saliva, and perinatal transfer—is critical. The Centers for Disease Control and Prevention (CDC) recommends a timely Hep B vaccine series and screening pregnant women to reduce mother-to-child transmission. By vaccinating your newborn early, you help break the chain of infection and protect them from lifelong complications.