A straw poll of public opinion on the top causes of death in many of the world's poorest regions might conceivably see the deadly triad of HIV/AIDS, malaria and tuberculosis emerge as frontrunners.
But, as I heard at the Overseas Development Institute (ODI) in London, United Kingdom, last week, there is another cause exerting an even greater toll on the world's population: road traffic injuries and traffic-related air pollution. And, compared with the hyper-visibility of HIV in global debates, this growing road safety crisis remains alarmingly absent from discussions.
Transport for Health, a report launched on 31 March by the World Bank and the Institute for Health Metrics and Evaluation at the University of Washington, United States, makes for grim reading.
Using Global Burden of Disease (GBD) methods to analyse multiple data sources gathered between 1990 and 2010, the report reveals that road accidents alone account for almost as many deaths as HIV/AIDS. However, if you add in the additional burden of disease caused by traffic pollution, motorised transport accounted for over 1.5 million deaths in 2010 - more than the individual cost of HIV/AIDS, malaria or tuberculosis.
The chart shows the incidence of road-related deaths compared with deaths caused by HIV/AIDS, TB, malaria and diabetes. Click to enlarge or click here for the data.
Deaths from road injuries and diseases related to transport air pollution have grown globally in the last two decades - up by 46 per cent and 11 per cent respectively.
But developing countries are bearing the brunt of this crisis. In the developing world, most transport-related deaths are caused by crashes rather than pollution, Marc Shotten, senior transport specialist at the World Bank Global Road Safety Facility and the report's joint author, told the meeting.
In regions where rapid motorisation, road infrastructure and mobility are closely linked to goals around economic growth, and taking into account demographic and human settlement trends, this crisis looks set to worsen.
These figures affirm the urgency of ramping up investments in road safety research. A comparison of aid available for HIV/AIDS research with aid given to road safety sheds further light on global neglect for this road safety crisis.
Shotten tells me that the Global Fund for HIV, malaria and tuberculosis disbursed roughly US$17 billion as of 2012, while it is estimated that donor funds distributed for road safety over the same period (2002-2012) equate to under one per cent of that total.
"Sadly, that is just where we are with this subject in terms of donor interest," he says. "This will demonstrably have to be picked up in the coming years to spur the type of catalytic funding we need to help developing countries start to proactively manage this problem."
Under-reporting of deaths and injuries from road crashes is also a major problem, said Kavi Bhalla, assistant professor at Johns Hopkins University, United States, and the report's lead author.
Transport for Health compares government statistics on deaths caused by traffic injuries with GBD estimates. The contrast between the figures is staggering. In some of the poorest parts of the world - often areas with the highest death rates from road accidents - GBD estimates for road traffic deaths are as much as six times government statistics.
The map shows the percentage of under-reported road-related deaths by country in 2010. Click to see map.
All this has a major impact on government policy and aid interventions.
And with inaccurate data under-playing the crisis in many countries, international donors may fail to recognise the scale of the crisis.