One Health: From Vision to Fashion

M. Kariuki Njenga, BVM, PhD

Washington State University Global Heath Program, Nairobi, Kenya and Kenya Medical Research Institute, Nairobi, Kenya

Surveillance of emerging infectious and endemic zoonotic diseases and response to their outbreaks has traditionally been undertaken separately by the human and animal health sectors with minimal collaboration between the disciplines. This has often resulted in inadequate prevention and control of the diseases.

A One Health (OH) approach that advocates for integrated human, animal, and environmental management of emerging and zoonotic diseases has gained momentum globally in recent years as part of a strategy to predict and prevent emerging infectious diseases that, apart causing loss of human lives, are exerting an enormous economic burden on the world governments. For example, the SARS (severe acute respiratory syndrome) outbreak cost approximately US$ 50 billion whereas the H5N1 avian influenza pandemic cost an estimated US$ 800 billion.

In response, the World Health Assembly revised and enacted the new International Health Regulations (WHO-IHR) in 2005, with an aim of ensuring early detection of public health emergency of international concern anywhere in the world, followed by timely response that does not necessarily result in undue disruption in international traffic and trade.

In recognition of the fact that over 60% of emerging infectious diseases are zoonotic, the revised IHR guidelines required that each country have coordination mechanism between human and animal health sectors, and a mechanism for surveillance of zoonotic diseases. So, how do countries implement this? The Government of Kenya has worked to institutionalize OH approaches by establishing an OH office, referred to as the Zoonotic Disease Unit (ZDU). The ZDU bridges between the ministries of livestock and human health, with a senior epidemiologist deployed from each ministry and the goal of establishing and maintaining collaboration at the animal and human health interface towards better prevention and control of zoonoses.

As a guide for the ZDU, the country developed a 5-year (2012 – 2017) strategic plan for the implementation of OH and a list of 17 priority zoonotic diseases. The objectives of the Strategic Plan are: (i) to establish structures and partnerships that promote OH in the country; (ii) to strengthen surveillance, detection, prevention, and control of zoonoses in both humans and animals; and (iii) to conduct research and training at the human-animal-ecosystem interfaces. To our knowledge, no other country has a ZDU-like office, making it a new model that may provide a template for adoption by other countries. For the respective sectors, the Ministry of Health adopted the revised Integrated Diseases Surveillance and Response (IDSR) guidelines from the World Health Organization (WHO)-African region that added endemic and epidemic prone zoonotic diseases to the countries disease priority reporting list.

In addition, the IDSR guidelines require formation of joint human and animal health outbreak response teams at the local and national levels in the event of a possible zoonotic epidemic. On its part, the Ministry of Livestock Development underwent an OIE requirement for assessment of the performance of veterinary services on OH in 2011, with an aim of identifying gaps within its system for successful OH implementation. Within academic institutions, work is ongoing to revise the teaching curricula for medical, veterinary, and public health students at universities and colleges to reflect the importance of integrating human and animal health approaches. All these efforts are part of the implementation of the Kenya OH Strategic Plan.

Successful implementation of Kenya’s OH strategic plan is likely to result in greater compliance with WHO/International Health Regulations on timely response to a public health event of international concern; and to OIE guidelines on animal-source food safety and public health threats. Success will be achieved through enhanced capacity for early detection, diagnosis, and rapid response to emerging and re-emerging diseases; and robust implementation of disease prevention and control strategies following risk maps that clearly identify hot spots for these diseases. In addition, studies targeting oft neglected human-animal interface are likely to result in better understanding of infection and transmission dynamics, ecology, and other drivers and the socioeconomic impact of zoonoses and emerging diseases. Whereas hurdles remain on the path towards a fully functional OH system in Kenya, there is no doubt the country is off to a good start, and well ahead of many countries.

A key goal for the proponents of OH approach is demonstration of how the OH approach enhances the public health and socio-economic well-being of the country. Developing smart and integrated human-animal programs that target surveillance for neglected zoonotic disease, disease reporting systems, disease management, outbreak response, and public education should ultimately be demonstrably beneficial for both sectors.