Public health impact of zoonoses and international approaches for their detection and containment.

Many new, emerging and re-emerging diseases of humans are caused by pathogens that originate from animals or products of animal origin. A wide variety of both domestic and wild animal species act as reservoirs for these pathogens, which may be viruses, bacteria or parasites. Given the extensive distribution of the animal species affected, the effective surveillance, prevention and control of zoonotic diseases pose a significant challenge. There are direct and indirect implications for public health of emerging zoonoses. Direct implications are defined as the consequences for human health in terms of morbidity and mortality. Indirect implications are defined as the effect of the influence of emerging zoonotic disease on health professionals and the general public. The tremendous indirect impact of emerging zoonotic diseases on public health policy and structures and on public perception of health risks is acknowledged. A biphasic approach for handling emerging zoonoses is proposed, i.e. a short- to intermediate-term response to an outbreak or emergency and a long-term comprehensive study of the ecology of the zoonotic pathogen. Resource-rich countries should invest in the establishment and strengthening of surveillance systems in resource-limited countries considering the international significance of emerging zoonoses. Based on the new international health regulations, emphasis should be placed on building the appropriate preparedness and response capacity in countries and on promoting intersectoral collaboration and coordination.