Summary The epidemiology of human brucellosis, the commonest zoonotic infection worldwide, has drastically changed over the past decade because of various sanitary, socioeconomic, and political reasons, together with the evolution of international travel. Several areas traditionally considered to be endemic—eg, France, Israel, and most of Latin America—have achieved control of the disease. On the other hand, new foci of human brucellosis have emerged, particularly in central Asia, while the situation in certain countries of the near east (eg, Syria) is rapidly worsening. Furthermore, the disease is still present, in varying trends, both in European countries and in the USA. Awareness of this new global map of human brucellosis will allow for proper interventions from international public-health organisations.

https://www.thelancet.com/pdfs/journals/laninf/PIIS1473309906703826.pdf

The new global map of human brucellosis

Objective To quantify the public health and economic burden of endemic canine rabies in Africa and Asia. Methods Data from these regions were applied to a set of linked epidemiological and economic models. The human population at risk from endemic canine rabies was predicted using data on dog density, and human rabies deaths were estimated using a series of probability steps to determine the likelihood of clinical rabies developing in a person after being bitten by a dog suspected of having rabies. Model outputs on mortality and morbidity associated with rabies were used to calculate an improved disability-adjusted life year (DALY) score for the disease. The total societal cost incurred by the disease is presented. Findings Human mortality from endemic canine rabies was estimated to be 55 000 deaths per year (90% confidence interval (CI) = 24 000–93 000). Deaths due to rabies are responsible for 1.74 million DALYs lost each year (90% CI = 0.75–2.93). An additional 0.04 million DALYs are lost through morbidity and mortality following side-effects of nerve-tissue vaccines. The estimated annual cost of rabies is US$ 583.5 million (90% CI = US$ 540.1–626.3 million). Patient-borne costs for post-exposure treatment form the bulk of expenditure, accounting for nearly half the total costs of rabies. Conclusions Rabies remains an important yet neglected disease in Africa and Asia. Disparities in the affordability and accessibility of post-exposure treatment and risks of exposure to rabid dogs result in a skewed distribution of the disease burden across society, with the major impact falling on those living in poor rural communities, in particular children.

/pdf/re-evaluating-the-burden-of-rabies-in-africa-and-asia-s3ebwayr11.pdf

Re-evaluating the burden of rabies in Africa and Asia

Background Rabies is a notoriously underreported and neglected disease of low-income countries. This study aims to estimate the public health and economic burden of rabies circulating in domestic dog populations, globally and on a country-by-country basis, allowing an objective assessment of how much this preventable disease costs endemic countries.

/pdf/estimating-the-global-burden-of-endemic-canine-rabies-1gkrw5vw7m.pdf

Estimating the global burden of endemic canine rabies.

From 'one medicine' to 'one health' and systemic approaches to health and well-being

Livestock keeping is critical for many of the poor in the developing world, often contributing to multiple livelihood objectives and offering pathways out of poverty. Livestock keeping also affects an indispensable asset of the poor, their human capital, through its impact on their own nutrition and health. This paper outlines the linkages between livestock keeping and the physical well-being of the poor, and examines a number of commonly held beliefs that misrepresent livestock development issues related to these linkages. These beliefs limit the scope of intervention programs to promote livestock and limit their potential contribution to poverty reduction. Recognition of the complexity of the role livestock play in household decision-making and of the opportunities foregone due to these misconceptions can enhance the ability of livestock to contribute to human well-being in the developing world.

/pdf/invited-review-role-of-livestock-in-human-nutrition-and-62fpessrxf.pdf

Invited review: Role of livestock in human nutrition and health for poverty reduction in developing countries.

OBJECTIVE: To estimate the economic benefit, cost-effectiveness, and distribution of benefit of improving human health in Mongolia through the control of brucellosis by mass vaccination of livestock. METHODS: Cost-effectiveness and economic benefit for human society and the agricultural sector of mass vaccination against brucellosis was modelled. The intervention consisted of a planned 10-year livestock mass vaccination campaign using Rev-1 livestock vaccine for small ruminants and S19 livestock vaccine for cattle. Cost-effectiveness, expressed as cost per disability-adjusted life year (DALY) averted, was the primary outcome. FINDINGS: In a scenario of 52% reduction of brucellosis transmission between animals achieved by mass vaccination, a total of 49,027 DALYs could be averted. Estimated intervention costs were US$ 8.3 million, and the overall benefit was US$ 26.6 million. This results in a net present value of US$ 18.3 million and an average benefit-cost ratio for society of 3.2 (2.27-4.37). If the costs of the intervention were shared between the sectors in proportion to the benefit to each, the public health sector would contribute 11%, which gives a cost-effectiveness of US$ 19.1 per DALY averted (95% confidence interval 5.3-486.8). If private economic gain because of improved human health was included, the health sector should contribute 42% to the intervention costs and the cost-effectiveness would decrease to US$ 71.4 per DALY averted. CONCLUSION: If the costs of vaccination of livestock against brucellosis were allocated to all sectors in proportion to the benefits, the intervention might be profitable and cost effective for the agricultural and health sectors.

https://who.int/bulletin/volumes/81/12/en/02-0434(2).pdf

Human health benefits from livestock vaccination for brucellosis: case study

Although industrialized countries have been able to contain recent outbreaks of zoonotic diseases, many resource-limited and transitioning countries have not been able to react adequately. The key for controlling zoonoses such as rabies, echinococcosis, and brucellosis is to focus on the animal reservoir. In this respect, ministries of health question whether the public health sector really benefits from interventions for livestock. Cross-sectoral assessments of interventions such as mass vaccination for brucellosis in Mongolia or vaccination of dogs for rabies in Chad consider human and animal health sectors from a societal economic perspective. Combining the total societal benefits, the intervention in the animal sector saves money and provides the economic argument, which opens new approaches for the control of zoonoses in resource-limited countries through contributions from multiple sectors.

/pdf/human-benefits-of-animal-interventions-for-zoonosis-control-4tf33qccik.pdf

Human Benefits of Animal Interventions for Zoonosis Control

Human rabies in developing countries can be prevented through interventions directed at dogs. Potential cost-savings for the public health sector of interventions aimed at animal-host reservoirs should be assessed. Available deterministic models of rabies transmission between dogs were extended to include dog-to-human rabies transmission. Model parameters were fitted to routine weekly rabid-dog and exposed-human cases reported in N'Djamena, the capital of Chad. The estimated transmission rates between dogs (beta(d)) were 0.0807 km2/(dogs x week) and between dogs and humans (beta(dh)) 0.0002 km2/(dogs x week). The effective reproductive ratio (R(e)) at the onset of our observations was estimated at 1.01, indicating low-level endemic stability of rabies transmission. Human rabies incidence depended critically on dog-related transmission parameters. We simulated the effects of mass dog vaccination and the culling of a percentage of the dog population on human rabies incidence. A single parenteral dog rabies-mass vaccination campaign achieving a coverage of least 70% appears to be sufficient to interrupt transmission of rabies to humans for at least 6 years. The cost-effectiveness of mass dog vaccination was compared to postexposure prophylaxis (PEP), which is the current practice in Chad. PEP does not reduce future human exposure. Its cost-effectiveness is estimated at US $46 per disability adjusted life-years averted. Cost-effectiveness for PEP, together with a dog-vaccination campaign, breaks even with cost-effectiveness of PEP alone after almost 5 years. Beyond a time-frame of 7 years, it appears to be more cost-effective to combine parenteral dog-vaccination campaigns with human PEP compared to human PEP alone.

https://www.pnas.org/content/pnas/106/35/14996.full.pdf

Felix Roth

Papers

Human health benefits from livestock vaccination for brucellosis: case study

Human Benefits of Animal Interventions for Zoonosis Control

Transmission dynamics and economics of rabies control in dogs and humans in an African city

A model of animal-human brucellosis transmission in Mongolia.

Economics of Bovine Tuberculosis