URBAN ZOO PROJECT: The 99 Household Study

Jan 12, 2016 | Blog, Latest news, Urban Zoo Project, Zoonotic Diseases

URBAN ZOO PROJECT: The 99 Household Study

The 99 households study is now well under way, with sampling being carried out across a range of neighbourhoods in Nairobi. Each week the team targets a different sub-location, where three house-holds are recruited; two with different types of livestock and a third which does not keep any livestock species. Our team of clinical officers and vets collect samples from all human members of the house-hold, along with samples from livestock present, from the general household environment and from any animal source foods in the home. In addition, the wildlife team trap and sample rodents, wild birds, bats, primates and small carnivores in the vicinity.

Sampling a household is intensive, and participants not only consent to donate their faeces to the study, but also give up a good portion of their time, answering questionnaires, aiding the sampling by handling their livestock, and providing access to their property at all hours to allow checking of rodent traps. As such, only three households are sampled in a week, but after 8 weeks more than 400 samples have already been collected.

All samples are sent to our two collaborating laboratories at KEMRI and the University of Nairobi, where they are cultured to grow E.coli bacteria, the primary focus of the study. Multiple individual bacterial colonies are selected from the first culture to go forward for purification and further testing. This means that each animal, human or environmental sample taken in the field can generate up to five subsequent bacterial isolates, and so the number of colonies in the collection is increasing rapidly.

Genetic data from the bacterial samples will allow us to study similarities and differences between these normal bacteria carried by individuals, and how they can be shared between humans, animals and the environment. The questionnaire data collected, among other things, builds on the project’s previous work on value chains, and will allow us to assess how these consumers from a range of social strata are connected to the various value chains that exist in Nairobi for meat and animal products.

A great deal of work has led up to the start of this study, including developing strate-gies for finding participants to represent a diverse section of the city, developing sampling and laboratory protocols, and designing the electronic data capture sys-tems used in the field and laboratories. Everyone involved is delighted that things are now up and running and our colleagues in the UK are eagerly waiting for the first shipment of bacterial DNA to arrive. Watch our blog space!

The 99 Households Study is part of the Urban Zoo Project http://www.zoonotic-diseases.org/project/urban-zoo-project/ which is a joint project between scientists from Kenya and the UK. We are interested in how diseases can be transmitted between animals and people living in close contact in a city environment. The 99 Household study aims to collect in-depth information from 99 families from 33 different neighbourhoods stratified by socio-economic status across the whole of Nairobi. We are testing humans, animals and the home environment for bacteria that can be shared and spread between them.

This article has been written by Judy Bettridge (Post Doc under the 99HH Study, based jointly between the University of Liverpool, UK and International Livestock Research Institute (ILRI) in Kenya).

Using tablet to collect data

Sampling a rabbit in Makongeni

Field team in one of the sampling sites

Sampling the environment

Microbiology plates in readiness for culturing samples

All about Pork-Safe Pork Conference

Jan 12, 2016 | Blog, Latest news, Urban Zoo Project

All about Pork-Safe Pork Conference

The 11TH Safe Pork conference was held from 7th to 10th September 2015 in Porto, Portugal. The Urban Zoo project was represented by Dr. Maurice Karani of ILRI and Dr. Pablo Alarcon of RVC.
The conference focused on the epidemiology and control of foodborne pathogens and antimicrobial resistance in pigs and pork along all produc-tion chains. Additionally, international exchange of ideas, research and policy themes related to the management of zoonosis and food safety in the pig and pork sector, with an integrated approach from “farm to fork” in relation to the “One Health” concept was explored

Our highlight of the conference was the oral presentation by Maurice Kara-ni, a veterinarian and a research assistant with the urban zoo project and an MSc student at the Royal Veterinary College titled, ‘Assessing and understanding food safety risk practices in Nairobi pork food system: a value chain approach’. The presentation was awarded the best oral presen-tation in the student category.
The work on Nairobi’s pig value chain, one of several Urban Zoo value chain outputs, will be published in 2016.

Urban Zoo Team — Out and About

Jan 12, 2016 | Blog, Latest news, Urban Zoo Project

Urban Zoo Team — Out and About

The International Symposium for Veterinary Epidemiology and Economics (ISVEE) 14th conference was held in Merida, Yucatan in Mexico from 3rd to 7th November 2015. The Urban Zoo group was well represented by Patrick Muinde, Pablo Alarcon, Paula Dominguez, Maud Carron, Joshua Onono, Judy Bettridge, Annie Cook and Jonathan Rushton.

Out and about

The theme of the conference was “Veterinary Epidemiology & Economics: Planning our future” and this group gave oral presentations in several streams in the confer-ence, including presenting much of the work on value chains; but also gave talks on food nutrition, zoonoses, animal health economics, statistics and food safety.

In addition to having some excellent talks, the social side of the conference was also highly enjoyable, with many opportunities to sample local food and see some of the historical sites around Yucatan. This also provided a chance to meet and discuss science with colleagues from around the globe.

WHO’s first ever global estimates of foodborne diseases find children under 5 account for almost one third of deaths

Dec 3, 2015 | Blog, Latest news, Zoonotic Diseases

WHO’s first ever global estimates of foodborne diseases find children under 5 account for almost one third of deaths

Overview

  • First ever estimates of the global burden of foodborne diseases show almost 1 in 10 people fall ill every year from eating contaminated food and 420 000 die as a result
  • Children under 5 years of age are at particularly high risk, with 125 000 children dying from foodborne diseases every year
  • WHO African and South-East Asia Regions have the highest burden of foodborne diseases

News release

3 DECEMBER 2015 | GENEVA – Almost one third (30%) of all deaths from foodborne diseases are in children under the age of 5 years, despite the fact that they make up only 9% of the global population. This is among the findings of WHO’s Estimates of the global burden of foodborne diseases – the most comprehensive report to date on the impact of contaminated food on health and wellbeing.

The report, which estimates the burden of foodborne diseases caused by 31 agents – bacteria, viruses, parasites, toxins and chemicals – states that each year as many as 600 million, or almost 1 in 10 people in the world, fall ill after consuming contaminated food. Of these, 420 000 people die, including 125 000 children under the age of 5 years.

“Until now, estimates of foodborne diseases were vague and imprecise. This concealed the true human costs of contaminated food. This report sets the record straight,” says Dr Margaret Chan, Director-General of WHO. “Knowing which foodborne pathogens are causing the biggest problems in which parts of the world can generate targeted action by the public, governments, and the food industry.”

While the burden of foodborne diseases is a public health concern globally, the WHO African and South-East Asia Regions have the highest incidence and highest death rates, including among children under the age of 5 years.

“These estimates are the result of a decade of work, including input from more than 100 experts from around the world. They are conservative, and more needs to be done to improve the availability of data on the burden of foodborne diseases. But based on what we know now, it is apparent that the global burden of foodborne diseases is considerable, affecting people all over the world – particularly children under 5 years of age and people in low-income areas,” says Dr Kazuaki Miyagishima, Director of WHO’s Department of Food Safety and Zoonoses.

Diarrhoeal diseases are responsible for more than half of the global burden of foodborne diseases, causing 550 million people to fall ill and 230 000 deaths every year. Children are at particular risk of foodborne diarrhoeal diseases, with 220 million falling ill and 96 000 dying every year. Diarrhoea is often caused by eating raw or undercooked meat, eggs, fresh produce and dairy products contaminated by norovirus, Campylobacter, non-typhoidal Salmonella and pathogenic E. coli.

Other major contributors to the global burden of foodborne diseases are typhoid fever, hepatitis A, Taenia solium (a tapeworm), and aflatoxin (produced by mould on grain that is stored inappropriately).

Certain diseases, such as those caused by non-typhoidal Salmonella, are a public health concern across all regions of the world, in high- and low-income countries alike. Other diseases, such as typhoid fever, foodborne cholera, and those caused by pathogenic E. coli, are much more common to low-income countries, while Campylobacter is an important pathogen in high-income countries.

The risk of foodborne diseases is most severe in low- and middle-income countries, linked to preparing food with unsafe water; poor hygiene and inadequate conditions in food production and storage; lower levels of literacy and education; and insufficient food safety legislation or implementation of such legislation.

Foodborne diseases can cause short-term symptoms, such as nausea, vomiting and diarrhoea (commonly referred to as food poisoning), but can also cause longer-term illnesses, such as cancer, kidney or liver failure, brain and neural disorders. These diseases may be more serious in children, pregnant women, and those who are older or have a weakened immune system. Children who survive some of the more serious foodborne diseases may suffer from delayed physical and mental development, impacting their quality of life permanently.

Food safety is a shared responsibility, says WHO. The report’s findings underscore the global threat posed by foodborne diseases and reinforce the need for governments, the food industry and individuals to do more to make food safe and prevent foodborne diseases. There remains a significant need for education and training on the prevention of foodborne diseases among food producers, suppliers, handlers and the general public. WHO is working closely with national governments to help set and implement food safety strategies and policies that will in turn have a positive impact on the safety of food in the global marketplace.

Note to the editor:

In addition to disease incidence and deaths, the WHO report and PLOS papers also quantify the disease burden in terms of Disability-Adjusted Life Years (DALYs)—the number of healthy years of life lost due to illness and death—to facilitate ranking between causes of disease and across regions. The global burden of foodborne diseases caused by the 31 hazards in 2010 was 33 million DALYs; children under five years old bore 40% of this burden.

The policy and social impact of this report will be discussed in detail at a symposium organised by WHO and the Dutch National Institute for Public Health and the Environment (RIVM), 15-16 December in Amsterdam.

Contact information

Fadéla Chaib, WHO
Telephone: +41 22 791 32 28
Mobile: +41 79 475 55 56
E-mail: chaibf@who.int

Olivia Lawe-Davies, WHO
Telephone: +41-22-7911209
Mobile: +41-794755545
Email: lawedavieso@who.int

 

?

View the full report

Click here to view report

?

FERG symposium

Click here to view symposium page

?

Infographic (click image)

Click here to view more infographics

?

Factsheet (click image)

WHO African Region

The WHO African Region was estimated to have the highest burden of foodborne diseases per population. More than 91 million people are estimated to fall ill and 137 000 die each year.

Diarrhoeal diseases are responsible for 70% of foodborne diseases in the African Region. Non-typhoidal Salmonella, which can be caused by contaminated eggs and poultry, causes the most deaths, killing 32 000 a year in the Region—more than half of the global deaths from the disease. 10% of the overall foodborne disease burden in this Region is caused byTaenia solium (the pork tapeworm).

Chemical hazards, specifically cyanide and aflatoxin, cause one quarter of deaths from foodborne diseases in the Region. Konzo, a particular form of paralysis caused by cyanide in cassava, is unique to the African Region, resulting in death in 1 in 5 people affected.

?

Click to view infographic

WHO Region of the Americas

The WHO Region of the Americas is estimated to have the second lowest burden of foodborne diseases globally. Nevertheless 77 million people still fall ill every year from contaminated food, with an estimated 9000 deaths annually in the Region. Of those who fall ill, 31 million are under the age of 5 years, resulting in more than 2000 of these children dying a year.

While the overall burden of diarrhoeal diseases is lower than in other Regions, it is still the most common foodborne disease in the Region of the Americas with Norovirus, Campylobacter, E. coli and non-typhoidal Salmonella causing 95% of cases.

Toxoplasmosis and the pork tapeworm (Taenia solium) are very important food safety concerns in the Central and South America. Toxoplasmosis is spread through undercooked or raw meat and fresh produce, and can result in impaired vision and neurological conditions.

?

Click to view infographic

WHO Eastern Mediterranean Region

The Eastern Mediterranean Region has the third highest estimated burden of foodborne diseases per population, after the African and South-East Asia Regions. More than 100 million people living in the Eastern Mediterranean Region are estimated to become ill with a foodborne disease every year and 32 million of those affected are children under 5 years.

Diarrhoeal diseases (caused by E. coli, Norovirus, Campylobacter and non-typhoidal Salmonella) account for 70% of the burden of foodborne disease.

An estimated 37 000 people in the Eastern Mediterranean Region die each year from unsafe food, caused primarily by diarrhoeal diseases, typohoid fever, hepatitis A, and brucellosis. Both typhoid fever and hepatitis A are contracted from food contaminated by the faeces of an infected person and brucellosis is commonly caused by unpasteurized milk or cheese of infected goats or sheep. Half of the global cases of brucellosis are in people living in this Region, with more than 195 000 people infected every year, causing fever, muscle pain or more severe arthritis, chronic fatigue, neurologic symptoms and depression.

?

Click to view infographic

WHO European Region

The report highlights that although the WHO European Region has the lowest estimated burden of foodborne diseases globally, more than 23 million people in the Region fall ill from unsafe food every year, resulting in 5000 deaths.

Diarrhoeal diseases account for the majority of foodborne illnesses in the WHO European Region with the most common being Norovirus infections, causing an estimated 15 million cases, followed by campylobacteriosis, causing close to 5 million cases. Non-typhoid salmonellosis causes the highest number of deaths—almost 2000 annually.

Foodborne toxoplasmosis, a severe parasitic disease spread through undercooked or raw meat and fresh produce, may cause up to 20% of the total foodborne disease burden and affects more than 1 million people in the Region each year. Listeria infection also has a severe impact on the health of people who contract it and causes an estimated 400 deaths in the European Region annually. Listeria can result in septicaemia and meningitis, and is usually spread by consuming contaminated raw vegetables, ready-to-eat meals, processed meats, smoked fish or soft cheeses.

?

Click to view infographic

WHO South-East Asia Region

The WHO South-East Asia Region has the second highest burden of foodborne diseases per population, after the African Region. However, in terms of absolute numbers, more people living in the WHO South-East Asia Region fall ill and die from foodborne diseases every year than in any other WHO Region, with more than 150 million cases and 175 000 deaths a year. Some 60 million children under the age of 5 fall ill and 50 000 die from foodborne diseases in the South-East Asia Region every year.

Diarrhoeal disease causing agents, Norovirus, non-typhoidal Salmonellaand pathogenic E. coli cause the majority of foodborne disease deaths in the Region. Additionally, the pork tapeworm (Taenia solium) has a major impact on health. It can cause cysts to develop in the brain, which is the most frequent preventable cause of epilepsy worldwide.

Globally, half of the people who are infected and die from either Typhoid fever or hepatitis A reside in the South-East Asia Region.

?

Click to view infographic

WHO Western Pacific Region

Every year, 125 million people in the WHO Western Pacific Region become ill from contaminated food, causing more than 50 000 deaths. As in other Regions, the burden is highest in children under 5 years of age with 40 million falling ill and 7000 dying every year.

Unlike other Regions of the world, where diarrhoeal diseases cause the highest proportion of deaths, aflatoxin is estimated to be the leading cause of foodborne disease deaths in the Western Pacific Region. Aflatoxin is a toxin produced by mould that grows on grain that has been stored inappropriately, and can cause liver cancer, one of the most deadly forms of cancer. More than 10 000 people in the Western Pacific are estimated to develop liver cancer due to aflatoxin every year, with the disease proving fatal in 9 out of 10 people. An estimated 70% of people who become ill from aflatoxin worldwide live in the WHO Western Pacific Region.

The Western Pacific Region also has the highest death rate from foodborne parasites, particularly the Chinese liver fluke (Clonorchis sinensis), Echinococcus multilocularis and Taenia solium (the pork tapeworm). The Chinese liver fluke, which is commonly contracted through raw and incorrectly processed or cooked fish, infects more than 30 000 people in the Region a year, causing death in 1 in 5 cases. Almost all of those who are infected with Chinese liver fluke in the world live in the Western Pacific. The highest disease burden results from the disabling impact ofParagonimus spp. infections of the lungs and central nervous system.

?

Click to view infographic

Zoonoses in Africa

Nov 10, 2015 | Blog, Latest news

Originally posted on the UK © Microbiology Society’s online magazine-Microbiology Today, issue: November 2015, Comment: Zoonoses in Africa

Introduction

Zoonotic diseases are those infections transmissible between animals and humans. Most diseases that infect humans are, in fact, zoonotic, highlighting that multi-host pathogens have a competitive edge by increasing the range of host environments in which they can survive. A recent briefing note by the Microbiology Society highlights that many zoonotic diseases are also emerging diseases – that is, either an altogether new disease, or a known disease that is increasing in incidence or increasing in geographical range.

Disease emergence happens because the world we (and our microbes) live in is changing (often because of the actions of humans, but also due to natural processes), giving pathogens new opportunities to infect new hosts, and creating new opportunities for hosts to interact with each other and share their infections. The intensification of farming, for example, leads to closer relationships between individual animals, generating opportunities for more rapid mutations as organisms move from host to host, while also providing a structured way for those pathogens to enter highly ordered food chains that branch out and reach very large numbers of people.

Zoonotic diseases are a global problem, with rich and poor countries both at risk, and practices in both highly developed and less developed economies predisposing to transmission. A significant difference, however, between a continent like Africa and one like Europe, is the ability of national and regional systems to detect and respond to zoonotic disease threats. Indeed, in work investigating where hotspots of disease emergence are located, developed countries stand out as being at higher risk, mainly only because more such events are detected in such places as a result of robust systems for monitoring and detection. Over the past couple of years, the struggle – now largely successful (but still not completed) – to contain the West African Ebola outbreak highlights this problem.

Other than the headline-hitting, large global outbreaks of zoonotic infections, human populations face a multitude of challenges from less dramatic, less fatal, diseases that cause long-term morbidity in large groups of people (morbidity refers to illness, as opposed to death, termed mortality). In Africa, several such zoonotic neglected diseases of neglected populations conspire to hinder the health of people and the animals they depend on for their livelihoods. This includes bacterial, protozoan and viral disease agents, transmitted in many ways.

Brief overview of some of the zoonoses

The World Health Organization (together with its partners) has been keeping a focus on these diseases, with a series of reports and policy recommendations published since 2006 (with the latest having been released earlier this year). We’ll look briefly at three of them.

A

Brucellosis is a bacterial disease caused by one of several organisms in the genus Brucella. Cattle, sheep and goats harbour this bacterium, which they transmit to each other and humans through milk or through contaminated abortion materials (the bacterium is abortogenic). It causes a chronic debilitating disease in humans with joint pain, fatigue and recurrent fever; brucellosis is often misdiagnosed as malaria and wrongly treated.

A

Rabies is a well-known but none-the-less neglected zoonotic infection, caused by the rabies virus. It is transmitted and maintained mostly in domestic dog populations (though in areas with a wildlife interface, the epidemiology may get more complex), which transmit the infection to humans through bites. It is best controlled by vaccinating the dog reservoir to prevent disease from developing if infection occurs, but a human vaccine is available both as a pre- and post-exposure course, and effective and timely delivery of the vaccine will minimise mortality.

A

Cysticercosis is a disease caused by the tapeworm Taenia solium. It has a relatively complex lifecycle, involving pigs eating Taenia egg-carrying human faeces that contaminates the environment, humans eating undercooked pork meat, and environmental contamination with eggs that can encyst in humans. The greatest problem with T. solium is that it may cause a neurological disease called neurocysticercosis in people who are infected with tapeworm eggs; in many developing countries, it is the single largest cause of acquired epilepsy in humans.

Way forward

For these diseases, and others like them, many aspects of their basic biology are well understood, and the transmission of the pathogens has been controlled in many countries. The outstanding issues, which require more research for the effective deployment of intervention efforts, are i) knowing how to integrate surveillance for the diseases into national systems (because having data on occurrence, distribution and disease burden is essential to prioritisation), ii) deploying, and in some cases developing, new and better tools to diagnose the infections in humans and animals (because accurate and efficient detection is key to both delivering cure and also to gathering good surveillance data), and iii) scaling up intervention strategies. The World Health Organization has stated that “we have existing knowledge and evidence that can be transformed into strategies and applied on a large-scale; we need to be able to capitalise on experience and the growing political commitment to involve other sectors, with community participation.”

Effectively tackling zoonoses requires a focus on transmission control, prevention and burden reduction in humans, but also control and transmission prevention in animals. This, in turn, requires a One Health approach, involving joint surveillance, joint control and joint policy management by veterinary, medical and other sectors. With respect to African countries, the weaker institutions that exist relative to many developing countries actually present a real opportunity in this regard, with greater possibility to strengthen those institutions with, in mind from the outset, a unified approach to disease management across sectors. Many efforts are under way to prime this process, and it is well under way in a number of places. A prime example of a One Health approach in action is the Zoonotic Disease Unit (ZDU) of the Government of Kenya, a joint initiative between the ministries responsible for human and veterinary health. It has, over the past few years, developed a highly regarded National Rabies Control Strategy, implemented large- scale studies to study brucellosis epidemiology, responded to many zoonotic disease outbreaks, and developed preparedness plans for epidemic zoonoses such as Rift Valley fever (for which 2015 is a high risk year due to unusual rainfall patterns). The ZDU is also very open to collaboration with research teams working in Kenya, including in the implementation of zoonotic disease surveillance activities.

Tackling zoonoses is a difficult, fascinating task; it requires a good understanding of biology, of the way environment influences disease, of human–animal interactions, of policy and of politics.

Prof. Eric FevreBy Eric Fèvre

Professor of Veterinary Infectious Diseases, Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Chester High Road, Neston CH64 7TE, UK, and International Livestock Research Institute, Old Naivasha Road, PO Box 30709-00100, Nairobi, Kenya

Pin It on Pinterest