Injuries
Unintentional injuries are the leading cause of death and disability among adolescents. In 2019, nearly 1,000,000 adolescents (10-19 years old) were killed in traffic crashes. Many of the fatalities were classified as “vulnerable road users,” i.e., pedestrians, bicyclists, or drivers of two-wheeled motor vehicles. In many countries, road safety laws need to be more comprehensive and enforcement needs to be strengthened. Instruction in safe driving techniques must also be provided for young drivers, and legal prohibitions on driving under the influence of alcohol and drugs must be strictly enforced for all age groups. The blood-alcohol limit for young drivers should be set at a lower level than for adults. It is recommended that novice drivers be issued driver’s licenses with a probationary period during which there is zero tolerance for driving under the influence of alcohol.
Drowning is also a leading cause of death among teens, with more than 30,000 teens estimated to have drowned in 2019, more than three-quarters of them boys. The most important measure to prevent this type of death is teaching children and teens to swim.
Violence
Interpersonal violence is the fourth leading cause of death for adolescents and young adults worldwide. The rate varies greatly by region. In low- and middle-income countries in the Region of the Americas, interpersonal violence is responsible for about one-third of all male adolescent deaths. According to the Global School Health Survey, 42% of adolescent boys and 37% of adolescent girls have experienced bullying. Sexual violence also affects a significant proportion of youth: one in eight youth report experiencing sexual violence.
In addition, adolescent violence increases the risk of injury, HIV and other sexually transmitted infections, mental health problems, poor academic performance and school attendance, premature pregnancy, reproductive health problems, and the risk of infectious and non-communicable diseases.
Effective approaches to violence prevention and response include parent education and supportive early childhood development, bullying prevention in schools, life and social skills development for children, and community-based approaches to limiting access to alcohol and firearms. Effective and attentive care and assistance for adolescent survivors of violence and ongoing support help overcome the physical and psychological effects.
Mental Health
Depression is one of the leading causes of illness and disability among adolescents, and suicide is the third leading cause of death in the 15 to 19 age group. Sixteen percent of the cumulative burden of illness and injury in adolescents and young adults aged 10 to 19 is attributable to mental health disorders. Half of all mental health disorders in adults begin to develop much earlier, before age 14, but are largely undetected and untreated at that age.
Adolescents’ well-being and mental health are affected by many factors. Violence, poverty, stigmatization, marginalization, living in a humanitarian disaster or instability can increase the risk of developing mental health disorders. The consequences of failing to address adolescent mental health disorders are felt in adulthood, causing damage to both physical and mental health and limiting adults’ ability to live fulfilling lives.
Developing social-emotional skills in children and adolescents and providing them with psychosocial support in schools and other contexts promotes their mental health. In addition, programs that strengthen the bonds between adolescents and their families and improve the quality of living conditions are important. When problems arise, they should be identified and addressed in a timely manner with the involvement of competent and attentive health professionals.
Alcohol and Drug Use
Alcohol use by adolescents is a serious concern in many countries. Alcohol leads to decreased self-control and increases the risk of dangerous behaviors, such as unsafe sex and dangerous driving. It is also a root cause of injuries (including those caused by traffic accidents), violence, and premature death. Alcohol use can also lead to health problems later in life and has a negative impact on life expectancy. Currently, more than a quarter of all 15-19 year olds worldwide – 155 million adolescents – drink alcohol. In 2016, the prevalence of occasional heavy alcohol use among adolescents ages 15-19 was 13.6%, and male adolescents were the most at risk.
Marijuana is the most commonly used psychoactive substance among young people, with about 4.7% of 15-16 year olds using marijuana at least once in 2018. Alcohol and drug use among children and adolescents causes neurocognitive changes that can lead to behavioral, emotional, social, and learning problems later in life.
Alcohol and drug use prevention is an important area of public health activity and can include strategies and interventions at both the population level and school, community, family, and individual levels of intervention. Establishing a minimum age for purchase and consumption of alcohol, banning child-oriented marketing and advertising of alcoholic beverages are among the key strategies to reduce adolescent alcohol use.
Tobacco use
The vast majority of people who currently use tobacco began doing so when they were teenagers. Measures such as banning the sale of tobacco products to minors (people under 18) and raising tobacco prices through higher taxes, banning tobacco advertising, and creating smoke-free environments are essential. Globally, at least 1 in 10 young people between the ages of 13 and 15 use tobacco, although the rate is significantly higher in some regions.
HIV/AIDS
In 2019, the number of adolescents (ages 10-19) living with HIV was estimated at 1.7 million, and approximately 90% of them lived in the WHO African Region (3). Despite a significant decrease in new HIV infections among adolescents from their 1994 peaks, approximately 10% of new HIV infections among adults still occur among adolescents, three-quarters of whom are girls (3). In addition, although the number of new infections appears to have declined in many of the most heavily affected countries, recent testing coverage has been low, suggesting that many adolescents and young people living with HIV are unaware of their HIV status (5).
Adolescents living with HIV have less access to antiretroviral therapy, lower adherence to treatment, more difficult to keep under observation and more difficult to achieve viral suppression. One of the key factors exacerbating this situation is the low level of adolescent-friendly services, including psychosocial interventions and support.
Adolescents and young adults need to be provided with information about HIV prevention and access to appropriate tools. This includes the ability to access HIV prevention interventions, including voluntary medical male circumcision services, condoms and pre-exposure prophylaxis, increased access to HIV testing and counseling, and the ability to establish closer contact with HIV treatment services for HIV-positive adolescents.
Other infectious diseases
The number of measles-caused deaths and disabilities among adolescents has decreased significantly due to increased childhood vaccination: in countries in the African region, for example, adolescent deaths decreased by 90% between 2000 and 2012.
Diarrhea and lower respiratory tract infections (e.g., pneumonia) are estimated to be among the 10 leading causes of death for adolescents aged 10-14 years. These two groups of diseases, along with meningitis, are among the top five causes of death for adolescents in low- and middle-income countries in Africa.
An infection such as the human papillomavirus usually occurs after the beginning of sexual activity and can lead not only to short-term consequences (genital warts) in adolescence, but also, more dangerously, to cervical cancer and other cancers that manifest decades later. The optimal age for HPV vaccination is early adolescence (ages 9-14), and it is estimated that if 90% of girls worldwide received the HPV vaccine, more than 40 million lives could be saved in the next hundred years. However, it is estimated that only 15% of girls worldwide received the vaccine in 2019.
Premature Pregnancy and Childbearing
In developing countries, approximately 12 million girls aged 15-19 years and at least 777,000 girls under the age of 15 have preterm births each year. Complications during pregnancy and childbirth are one of the leading causes of death among girls aged 15-19 worldwide.
According to the UN Population Division, the global teen birth rate in 2020 was 41 births per 1,000 adolescent girls, with country rates ranging from 1 to 200 births per 1,000 girls (5). This indicates a significant decline in the number of adolescent births since 1990. In parallel with this decline, the maternal mortality rate for girls aged 15 to 19 years has also declined.
One of the targets of the Sustainable Development Goal health-related goal (SDG 3) is to achieve global universal access to sexual and reproductive health services by 2030, including family planning services, information and education, and the integration of reproductive health into national policies and programmes.
Adolescents have a right to the comprehensive sexuality education they need, which is a formalized learning process of teaching and learning about the cognitive, emotional, physical and social aspects of sexuality. Improving access to contraceptive information and services can reduce premature pregnancies and births at too young an age among girls. Introducing and enforcing legislation that sets the minimum age for marriage at 18 can help.
If teenage girls become pregnant, quality prenatal care must be provided. If allowed under current law, adolescents who choose to terminate a pregnancy should have access to safe abortion services.
Nutrition and micronutrient deficiencies
In 2016, iron deficiency anemia was the second leading cause of lost years of life among adolescents due to death and disability. In addition, iron and folic acid supplements promote the health of adolescents who will eventually become parents. In areas where intestinal helminths such as ankylostomas are common, regular deworming is recommended to prevent micronutrient deficiencies (including iron).
Forming healthy eating habits in adolescents is the basis of good health in adulthood. Combating food advertising that is high in saturated fats, trans-fatty acids, free sugars and salt, and increasing access to healthier foods and creating opportunities for physical activity are important for all age groups, but especially for children and adolescents.
Malnutrition and obesity
Many boys and girls in developing countries enter adolescence chronically undernourished, making them more vulnerable to disease and the risk of premature death. In parallel, the number of overweight or obese adolescents in both low- and middle-income and high-income countries is increasing.
Globally, about 1 in 6 adolescents aged 10-19 years were overweight in 2016. The prevalence of overweight in different WHO regions ranges from less than 10% in the Southeast Asia Region to over 30% in the Region of the Americas.
Physical Activity
Physical activity has fundamental health benefits for adolescents, such as improving respiratory, cardiovascular, muscular and bone health, maintaining a healthy body weight, and enhancing psychosocial well-being. The WHO recommends that adolescents should average at least 60 minutes of moderate to vigorous physical activity daily during the week in the form of games, sports, and active modes of transportation (such as bicycling and walking) or physical education.
Globally, it is estimated that only one in five adolescents can meet these recommendations. A high prevalence of physical inactivity is found in all WHO regions, with higher rates among adolescent girls than boys.
In order to increase physical activity levels nationally, society at large and local communities must create safe and supportive environments and opportunities for all adolescents to engage in physical activity.