We appreciate the insightful responses provided by Drs Pinsky , Mann , Obot  and Caetano  on our commentary  regarding differences in southern versus northern hemisphere approaches to the control and prevention of drinking and driving (DWI). Dr Obot's point about the significant burden of alcohol-associated road traffic mortality in sub-Saharan Africa is absolutely correct; the World Health Organization (WHO)'s Global Status Report on Road Safety highlights DWI as a major problem in many countries in Africa, Asia and Latin America . Evidence-based interventions are needed urgently across most countries in order to combat this important issue. We also appreciate Dr Mann's points about the continued work that needs to be conducted in the United States and Canada; issues of further lowering the legal blood alcohol concentration (BAC) limit and conducting random breath testing (RBT) are also very much on our minds, as is the constant tension between rigorous public health evidence versus the well-organized lobby of the alcohol industry.
In discussing the behavior paradox between US-born Hispanics versus Hispanic immigrants, Dr Caetano highlights an important point—the perception of deterrence may, in fact, be one of the factors that defines behaviors such as DWI, and we might hypothesize that immigrants from countries with lax attitudes towards DWI would have a strong perception of the law and its enforcement when driving in a more organized environment. Gibbs states that deterrence can be ‘[ . . . ] thought of as the omission of an act as a response to the perceived risk and fear of punishment for contrary behavior’. As Snortum mentions , it is the threat of formal sanctions that can be weakened or increased according to drivers' perceptions of how laws are enforced; this is why RBT might have a role in reducing the prevalence of DWI [9,10]. A combination of efforts stemming from public health professionals, government and law-enforcement personnel, and advocacy organizations such as Mothers against Drunk Driving (MADD), could play a strong role in the efforts to decrease DWI: the goals would be legislative lobbying and increased public awareness, in conjunction with strong and targeted enforcement. The role of these organizations has been recognized in providing critical services in advocacy, legislative lobbying, public education and victim support in the United States; the National Highway Traffic Safety Administration, among others, recognizes the potential impact of these organizations and frequently partners them in control efforts [11–13]. There are many similar advocacy groups in the northern and southern hemispheres [14,15] with track records of lobbying and community education; such organizations can become even more effective in advocacy and public education through involvement in government-run interventions, and resource and training support.
We hope the ‘Não foi um acidente’[‘It was not an accident’] movement  mentioned by Dr Pinsky will catch on in Brazil and many other countries; recognizing that drinking and driving is a preventable offense instead of a ‘random accident’ is a change in thinking and culture that, if achieved, will go a long way towards combating this significant public health concern.