Could Human-to-human Transmission of Avian Influenza Spark a Public Health Crisis in Southeast Asia?

•There is much uncertainty in predicting the next major incidence of influenza A. •Sources of recent clinical cases of A/H5N1 in Cambodia and Vietnam are unknown. •A/H5N1 is highly virulent in farmed poultry and can crossover to infect humans. •Human-to-human transmission would pose a significant public health threat. •Regional pandemic preparedness in Southeast Asia is required to mitigate this risk.