Road injuries killed more ten- to 19-year-olds than any disease did in 2013, shows a study based on a global health survey.
The trend in road deaths for this age group is "stagnant or increasing" in most developing countries, the researchers say, warning that "with increasing motorization, these trends are likely to worsen unless decisive action is taken".
"Road injuries were the leading cause of death among adolescents globally," killing about 115,000 young people that year, compared with about 76,000 deaths due to HIVAIDS, researchers write in an article, published last week (25 January) in JAMA Pediatrics, based on the Global Burden of Disease Study 2013.
HIV/AIDS remained the top killer for this age group in most of Sub-Saharan Africa, but road injuries were the leading cause of adolescent deaths in Argentina, Egypt, Indonesia, Mexico and Sudan, among other countries.
For children aged between five and nine, the most common cause of death in 2013 globally was diarrhoeal disease, but road injuries remained the top killer in North America, Latin America and the Caribbean, the study shows.
"Most people do not realize that road injuries are the second [biggest] cause of death in five- to 14-year-olds in developing countries, and the first in developed [countries]," says study coauthor Theo Vos, a health researcher at the University of Washington in the United States.
Road safety is now included in the UN's Sustainable Development Goals, and a group of governments has committed to improve law enforcement, road infrastructure and vehicle safety as part of the UN Decade of Action for Road Safety 2011-2020.
But "the pace of change is too slow", Margaret Chan, director-general of the World Health Organization, said last October as the WHO released a road safety report.
The NGO Amend tries to improve road infrastructure in several countries in Sub-Saharan Africa, for example by building road humps to slow traffic, improving pavements, moving school gates or painting zebra crossings on roads near schools to give pedestrians right of way.
In one project focused on five schools in Tanzania's capital, the NGO's efforts helped to reduce the health impact from one death and eight injuries a year to just one injury a year.
Separating vehicles from more vulnerable road users such as pedestrians, controlling vehicle speeds and improving pedestrian crossings would help make roads safer, especially for children, says the NGO's deputy director, Tom Bishop.
But Amend executive director Jeffrey Witte says road safety improvements not only require more money, but also greater political will and enforcement. He agrees with the study's authors that the situation is likely to worsen in the next decade in Africa as more and more vehicles are introduced on the roads.
 Global status report on road safety 2015 (WHO, October 2015)