Reports of cases of pertussis, also known as whooping cough, are currently five times higher compared to last year, according to the Centers for Disease Control and Prevention. The rise indicates the U.S. is returning to pre-pandemic patterns of typically 10,000-plus cases each year, and that mitigation measures such as masking and remote learning during the pandemic lowered transmission, the CDC said. The agency said that vaccination is the best way to prevent pertussis, but it expects cases to continue to increase among vaccinated and unvaccinated populations.