Authors:
Erin Hamilton, Institute for Health Metrics and Evaluation, University of Washington, Seattle, Washington, USA
Amy Peden, Royal Life Saving Society, Sydney, New South Wales, Australia and School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
Richard Franklin, College of Public Health, Medical and Veterinary Science, James Cook University, Douglas, Queensland, Australia and Royal Life Saving Society, Sydney, New South Wales, Australia

When we talk about global health, we hear about major causes of death and why people are dying, but how many people really die in each country? How much do causes of death vary across time, by age, or sex?  Are we hearing more about some conditions over others? Why? Why is it even important to know?

Globally, injury is a leading cause of preventable death. Understanding how people are dying from injury helps policy makers reduce communities’ risk of injury more effectively while providing researchers with the tools to explore and prevent these premature deaths. Since 2010, BMJ Injury Prevention has published multiple series of papers from the Institute for Health Metric’s Global Burden of Disease (GBD) study that highlight the global impact of death and disability from injuries.  Estimates for 2017 indicate that almost 4.5 million people died due to injury, while 520 million new cases of non-fatal injury occurred that year.

Drowning is a top ranking injury (5^th) that causes death globally, but there is still a lot we don’t know. This is, in part, due to the fact that the data we have on drowning is suboptimal. What we do know about drowning is children are most at risk, and the vast majority of drowning deaths occur in low and middle-income countries (LMIC). Paradoxically, this is where accuracy of drowning data is poorest, due to the speed at which drowning death occurs and challenges associated with counting deaths.

In early 2020, the first GBD drowning paper was published in Injury Prevention. The study estimated 295,000 people around the world lost their lives to unintentional drowning in 2017, a 45% reduction since 1990. Despite the challenge of not having data from each country and population, the GBD study leverages the data we do have globally and uses statistical modeling tools to provide a comprehensive set of disease, injury, and risk factor estimates for 195 countries and territories.

When we look at the trends of death from unintentional drowning, there are patterns we’re able to explain and others where very little is still understood.

What we know:

• Drowning deaths are declining over time globally, irrespective of the region
• China, India, Pakistan and Bangladesh accounted for over 50% of all drowning deaths in 2017
• More males than females die from drowning (~2 males for every 1 female)
• We see high rates of drowning death in landlocked countries, including the Central African Republic, Tajikistan, and Belarus, and a significant number of drownings happen in small bodies of water, such as ponds, ditches, streams, and wells
• With economic development, we see positive changes in patterns of drowning. However, children who live close to water are always more at risk, whether it be a well, ditch or swimming pool.

What we don’t know:

• Why, globally, drowning deaths are decreasing – many have speculated, but more information is needed
• The true incidence of drowning in specific regions and countries, particularly Latin America, Africa, and the Pacific
• The cause(s) of a sudden increase in drowning in the Oceania region and Papua New Guinea in particular
• The health effects of non-fatal drowning
• The best ways to prevent drowning among adults
• The particular context in which drowning is occurring in specific locations, which requires more quantitative and qualitative data

Closing these gaps in our global understanding is vital to continue to reduce loss of life for those impacted by drowning. The WHO has called for improvements in drowning data collection as one of a range of strategies aimed at preventing drowning, but this will cost money and require improvements at a systems level. Political will is needed to address these deficiencies in our knowledge. The drowning prevention community, and those passionate about water safety, may well achieve traction by linking drowning to broader global agendas such as access to safe water, urban design, and safe migration (a human rights issue). Without addressing and reducing the drowning risk of our most vulnerable, we are not going to adequately prevent drowning.  We need to ask ourselves, “If we know a lot about some diseases and injuries in developing countries, why do we not know more about drowning?”

GBD is one resource—a powerful resource—with multiple data sources that is helping us understand the burden of injury.  It will allow for greater exploration of the impact of policies and help to inform direction for future investment. The quality of GBD outputs depend on the quality and diversity of data inputs. If you have data to contribute, please consider contacting our network engagement team: data@healthdata.org.

If you or your research group is focused on drowning in your country or region, we’d love to hear your feedback. Maybe you know something we don’t know!

Competing interests: Dr Franklin reports receiving airfare reimbursement from Royal Life Saving Society – Australia, during the conduct of the study.