Centres for Disease Control and Prevention (CDC) services

vaccines are licensed in the United States, CDC actively monitors the safety of these vaccines through several systems.  If any vaccine is found to cause health problems, the vaccine may be withdrawn and no longer given to the public.Through vaccine safety monitoring, we also make sure new vaccines are safe for people who are at high risk of complications if they get a disease, such as the elderly, those with chronic medical conditions, and pregnant women. In some cases, these high-risk groups may not be included in clinical trialsso it is critical to monitor the safety of vaccines in these populations.

Approximately 79 million Americans are infected with human papillomavirus (HPV), and approximately 14 million people will become newly infected each year. Some HPV types can cause cervical, vaginal, and vulvar cancer among women, penile cancer among men, and anal and some oropharyngeal cancers among both men and women. Other HPV types can cause genital warts among both sexes. Each year in the United States an estimated 26,000 new cancers attributable to HPV occur, 18,000 among females (of which 11,500 are cervical cancer) and 8,000 among males (of which 5,900 are oropharyngeal cancers).

Attention-deficit/hyperactivity disorder (ADHD) is a serious public health problem affecting a large number of children and adults. We know that ADHD causes problems in how well children do in school, in their ability to make and keep friends, and function in society. Although there are treatments to improve ADHD symptoms, less is known about managing ADHD as a child ages and reaches adulthood.