Schools, businesses, the military and local governments are requiring proof of vaccination. Yet, unlike the European Union and Australia, which have secure digital proof of vaccination, the United States has not created a systematic way to track vaccinations around the nation. Most places in the U.S. instead rely on paper cards with handwritten notes, which can be easily forged.As scholars of health law and criminal law, we know that people who forge their own vaccine cards or buy forged cards are already facing criminal …