It is no longer rare for inhabitants of the Global South to die from cancer or diabetes. In these regions, non-communicable diseases now cause more deaths than infectious ones. This is due to changing diets and new—more urban and industrialised—lifestyle habits. Populations must also cope with the emergence or return of certain infectious diseases. Along with these transitions, the health field has a vested interest in patient experts, and mediators, of their illness. IRD researchers and their partners are taking stock of these developments to support patients to the best of their ability.
The Chronic Disease Epidemic
Living in a polluted city, smoking, engaging in very little physical activity and eating industrialised food: these are the characteristics of “modern life”, which are now common in Latin America, Asia and Africa. Chronic non-communicable diseases (NCDs) such as cardiovascular disease, diabetes and cancer have become more common than infectious diseases in these regions. Thus, out of the 15 million annual premature deaths People dying between the ages of 30-69associated with NCDs worldwide, more than 85% occur in low- and middle-income countries.
An alarming finding
“In these regions of the world, the epidemiological transition goes hand in hand with the emergence of a middle class”, said André Garcia, medical epidemiologist and director of UMR MERIT. “Urban populations, including the poorest inhabitants, now live in highly polluted areas, get very little exercise and have altered their eating habits: they view access to this way of life as a sign of development. But it is having a negative impact on their health.”
In Cotonou, Benin’s largest city, respiratory diseases (asthma, bronchiolitis) have been on the rise among children for the past decade. This is due to exhaust fumes from cars, industrial fumes and fumes from the firewood and coal used by inhabitants for cooking and light. “Even toddlers and infants under three months of age can be affected”, warned Maroufou Jules Alao, a paediatrician at Lagune Mother-Child University Hospital in Cotonou. “We didn’t see cases like these a few years ago. Childhood obesity is also on the rise. We found that half of the children of executives living in Cotonou are overweight. The authorities cannot remain indifferent to this observation.”
Prioritising prevention over cure
This exceedingly rapid NCD “epidemic” poses a challenge for public authorities who are not sure how to combat it. Previously mobilised in the fight against infectious diseases and supported by international donors and research programs, health professionals must now receive additional training to manage these conditions. “The healthcare systems in place are not equipped to treat these chronic disease”, stated André Garcia. “Treatments are expensive and not readily available. Furthermore, the socially disadvantaged are the most affected and die more prematurely as a result of NCDs: this is because they have restricted access to both care and information. The first line of action thus consists of developing prevention campaigns, in schools for example.”
Meanwhile, priority should be given to the surveillance and monitoring of behavioural and metabolic risk factorsFactors increasing the probability of developing a disease or suffering from a trauma. The World Health Organisation (WHO) also advocates monitoring the consequences of these risks (disease-specific morbidity and mortality) and country health system responses.The collection of such data will make it easier to assess these non-communicable diseases and thus better prevent them.
“We are currently collecting data by monitoring children, mostly in Cotonou, over the course of several years”, said Maroufou Jules Alao. “We would like to extend this data collection to rural populations in order to establish a general overview of the situation. The goal is to come up with recommendations that people can follow. This is why it is our duty to alert public authorities of the urgent need to act.”
The Dangers of Junk Food
An obesity epidemic in the Global South? Not long ago, this was inconceivable. Today, two-thirds of the world’s overweight population lives in Asia, Latin America and Africa. This development first affected middle-income countries and urban areas. It now concerns the least developed countries and is spreading to rural areas.
This is due to an obesogenic environment, which includes poor nutrition. “The inhabitants of these countries consume large amounts of fat, sugar and salt. Most of their foods are industry produced”, explained Pierre Traissac. “They get little daily exercise, whether at work, in transit or during their leisure time. They also get less sleep, which increases their risk of obesity.”
This process, dubbed nutritional transition, corresponds to gradual lifestyle changes—particularly dietary shifts—with a significant increase in the consumption of animal fats and processed foods. While this shift began several generations ago in the West, it took place in just a few decades in Global South. Coupled with the demographic transition, it resulted in a sharp increase in obesity and associated chronic diseases such as diabetes, hypertension and cardiovascular disease. The populations of these countries suffer from this situation in two ways: they or their ancestors have often experienced periods of nutritional deficit during their childhood. The expression of their genetic heritage is thus better adapted to a state of undernutrition, which favours the development of obesity.
High-risk food environments
These individuals are also surrounded by an unhealthy food environment. They are eating out more frequently and doing so at snack bars and fast food restaurants, where the food is of poor nutritional quality. Even at home, processed foods, rich in trans fatsForm of fat derived from the partial hydrogenation of vegetable oils that increase cardiovascular risk, have become common, while sweetened drinks and soft drinks are regularly consumed. Fruits and vegetables—which are more expensive because they are often destined for export—are neglected, even though they offer protection against these types of diseases.
The nutritional transition does not affect all social groups equally. The risk to women is greater, particularly in certain regions. “In Tunisia, women are three times more likely than men to become obese”, explained Jalila El Ati, Head of the “Studies and Planning” Department at the National Institute of Nutrition and Food Technology of Tunisia. “While pregnancy and breastfeeding predispose women to body fat gains, this obesity differential does not exist in European countries. Today, only the most highly educated women, exercising a profession, do not exhibit this male/female weight differential. This is because of their increased equality within the household and the public sphere.”
While obesity has primarily affected the wealthiest social classes, it is now affecting the poorest. If the nutritional transition in this region follows the Western example, these disadvantaged populations will exhibit high obesity rates in the future, adding to existing inequalities.
A double burden of malnutrition
Nutritional deficiencies continue to exist. In many households, obese adults live with stunted children: this is the double burden of malnutrition. Obese individuals, most notably women, may also suffer from nutritional deficits such as iron deficiencies. This is due to a poor quality—often industrial—diet high in calories but low in vitamins and minerals.
How can these various forms of malnutrition be prevented? “The environment determines people’s behaviour”, affirmed Pierre Traissac. “For example, if fruits and vegetables are too expensive, prevention messages will not work. States are trying to act by offering incentives to agri-food stakeholders. But their task is difficult: they have to face companies whose profits come from the sale of unhealthy food.”
Tunisia has thus launched a national obesity prevention plan based on research projects conducted in collaboration with the IRD. In Bizerte, a town in northern Tunisia, bakers were encouraged to reduce the amount of salt in their bread by 40%. In return for their efforts, the State has set up a promotional display encouraging consumers to buy from these bakers. The government has also asked manufacturers to use unprocessed natural ingredients (flour, eggs, wheat bran) and jam with no added sugar to make biscuits for children. A special “Good for Your Health” label has been created for these products in order to motivate manufacturers. Jalila El Ati added: “We hope to broaden the scope of these pilot projects and extend them to other economic actors. I am quite optimistic: certain manufacturers are enthusiastic and want to get involved. Our objective will then be to legislate regulatory levels of sugar, salt and trans fats in industrial foods. Beyond incentives, regulation is an essential step towards concrete action.”
Ethiopia, alleviating nutritional deficiencies with injera
The nutritional transition is already taking place in Ethiopia. Nevertheless, Ethiopians, who generally eat few vegetables, continue to suffer from nutritional deficits, particularly folate deficiencies. This deficiency presents a major risk to foetal development during the first three months of pregnancy: it can cause central nervous system birth defects and lead to mental retardation. To address this issue, JEAI AnemiNut (dietary ways to combat NUTritional ANEMIa) has cultivated microorganisms that promote fermentation and produce folates. “These lactic acid bacteria can be added during the production of injera, a flatbread made of teff flour (a cereal native to the region). Injera is a staple of the Ethiopian diet”, explained IRD microbiologist Christèle Humblot (UMR Nutripass). “Bacterial fermentation increases folate concentration in the injera, providing 30% of the daily recommended allowance.” After successful laboratory tests are conducted, scientists hope to produce these ferments in large quantities. Ethiopians will then be able to use them to produce injera on a daily basis and thus reduce their risk of folate deficiency.
- Infectious Diseases: the Challenge of Prevention
“Prevention is still the best medicine!” While this statement appears logical, it constitutes a new paradigm in the fight against infectious diseases. “We must move away from an approach that is primarily based on diagnosis and treatment: it leaves pathogens one step ahead”, explained Frédéric Simard. As director of the MIVEGEC unit, Simard studies the behaviour of infectious disease vectors (mosquitoes, ticks, bedbugs, etc.). To use his own words, he has been “running after pathogens” for research purposes for several years. “Currently, there are very few accessible vaccines and treatments to effectively treat infectious diseases. So, in order to prevent epidemics, we must determine where the threat comes from, study pathogens before they attack humans and identify transmission channels, risk behaviours and conditions that promote the emergence and spread of these diseases in humans. We must be able to pre-empt the fight against pathogens and their transmission through the informed management of the socio-ecosystems in which they occur.”
This evolution is taking place in a context of emerging new infectious diseases. Through deforestation operations, humans are increasingly in contact with wild animals. Many of these animals carry viruses. As for vectors, they have become resistant to insecticides and have adapted to human habits. For example, Anopheles mosquitoes now settle in cities, while previously they couldn’t tolerate pollution. They now bite during the day, outside the house: insecticide-treated nets are therefore less useful. Finally, transport globalisation has favoured the circulation of insects, such as Aedes albopictus, also known as the tiger mosquito, a vector of Zika, chikungunya and dengue fever. Originally from Asia, it colonised all continents in approximately thirty years’ time.
Prevention is the first step in the fight against infectious diseases. “In Burkina Faso, arbovirus transmission is monitored through entomological surveillance(1)”, explained Roch Dabiré, medical entomologist and regional director of the Research Institute for Health Sciences (IRSS) in Bobo-Dioulasso. “We are studying mosquito population dynamics in the cities most affected by dengue fever, including Ouagadougou and Bobo-Dioulasso, as well as the insecticide resistance of potential vectors, such as Aedes aegypti. We regularly set traps to assess their presence in the area. We can thus sound the alarm whenever there are population increases, prior to an epidemic breaking out.” Scientists also carefully monitor the areas that follow the railway line between Côte d'Ivoire and Ouagadougou: they are on the lookout for tiger mosquitoes (Aedes albopictus), which are found in the neighbouring country.
The second step is the fight against lymphatic filariasis [note: Caused by an infection of thread-like worms, this disease is characterised by the abnormal enlargement of body parts, hence the synonym elephantiasis] spearheaded by the National Neglected Tropical Disease Programme: the disease remains endemic in southwestern and eastern Burkina Faso. This programme focuses on communication and prevention through mass treatment with ivermectinA drug used to control several types of parasitoses to combat the persistence of parasites.
This surveillance system has also revealed cases of Onchocerca volvulus infection, an onchocerciasis parasiteTransmitted by midges, the infection causes itching, eye disease and epilepsy. found in the Burkina Faso Cascades Region (on the border with Côte d’Ivoire), although it has practically disappeared in other parts of the country. “Those who are infected are mostly displaced people from the Côte d’Ivoire”, said Roch Dabiré. “IRSS carefully monitors regions bordering the Côte d'Ivoire, as the latter’s healthcare system was disrupted during the 2002-2012 civil war. The action plan that we’ve put in place to eliminate this disease is extremely local in nature and will continue until this disease disappears (with a target date of 2025).”
Multidisciplinary and multisectoral prevention
Today, scientists are working on multidisciplinary and multisectoral prevention systems. Such systems must be cross-border and integrate public (urban planning, transportation) and private (import/export, tour operators, etc.) stakeholders whose activities promote the diffusion of pathogens and vectors, particularly in terms of dengue. In the absence of a vaccine for most of these diseases, excluding yellow fever, vector control is an important preventive measure. Research and the use of innovative technologies adapted to each context will have a real impact on the fight against infectious diseases.
Ces patients experts
Comment un patient peut-il s’impliquer dans son parcours de soin ? Le faire évoluer en fonction de ses besoins, de ses attentes ? Au Sud, cette participation est rare car les relations entre patients et médecins sont souvent de type paternaliste. Ces derniers disposent d’une forte autorité et prennent rarement le temps d’expliquer leur diagnostic. En face d’eux, les malades ne questionnent pas l’avis médical car ils connaissent généralement peu les pathologies et les traitements. Il leur est, en outre, souvent difficile d’accéder aux soins.
Pourtant, l’émergence d’associations mondiales de patients atteints du virus d’immunodéficience humaine (VIH) s’impliquant dans leur parcours de soins a permis à certains malades africains de faire évoluer leur rapport aux professionnels de santé. « Il y a une vingtaine d’années, des personnes vivant avec le VIH au Sénégal se sont regroupées dans des associations au sein desquelles ils s’entraident, discutent de leur maladie, de leur traitement et portent des revendications collectives », explique Bernard Taverne, anthropologue à l’IRD et directeur adjoint de l’UMR TransVIHMI. Certains d’entre eux sont devenus des patients experts : ils ont acquis de réelles connaissances médicales et peuvent discuter d’égal à égal avec les médecins. Ils sont devenus médiateurs associatifs et accompagnent les autres malades, sur le plan aussi bien social que médical. »
Un accompagnement psycho-social
Ces médiateurs jouent le rôle d’interface entre les patients et les médecins. Ils introduisent les malades au sein des structures de soin et de recherche, leur expliquent les prescriptions. Une grande majorité d’entre eux sont d’anciens malades qui souhaitent aider des personnes souvent démunies face à la complexité des traitements. C’est le cas de FatoumataCentre de Recherche et de Formation à la prise en charge du VIH (CRCF) du CHU de Fann de Dakar : «J’étais malade lorsque je suis arrivée au CRCF, précise-t-elle. J’ai été accueillie et j’ai été accompagnée par des médiatrices qui m’ont expliqué les soins. Depuis, je souhaite moi aussi aider les personnes malades à leur arrivée au CHU. Nous souhaitons qu’elles soient autonomes, qu’elles comprennent et s’impliquent dans le processus médical. »: sa maladie a été diagnostiquée en 2002 et elle accompagne depuis une quinzaine d’années des malades au sein du
L’accompagnement est en premier lieu pratique et psychologique. Le patient est guidé dans la structure médicale et des aides lui sont proposées lorsqu’elles sont disponibles - repas communautaires, prise en charge du transport - afin de le soulager financièrement. Les médiateurs ont pour objectif de redonner confiance aux malades et de défendre leurs droits. « Nous avons de très bonnes relations avec les chercheurs et les médecins, continue la médiatrice. Nous accompagnons les patients lors des consultations et nous essayons de leur donner toutes les informations disponibles sur les soins proposés. »
Indispensables mais précaires
D’abord bénévoles, les médiateurs se sont professionnalisés au fur et à mesure. Ils sont aujourd’hui environ 150 au Sénégal mais leur statut demeure cependant précaire. Tantôt soumis à des contrats courts souvent intermittents, tantôt bénévoles indemnisés, leur engagement est avant tout personnel. Ils sont devenus indispensables aussi bien pour les patients que pour les professionnels de santé et les chercheurs. « Les médiateurs peuvent être les porte-paroles des résultats de la recherche sur le VIH vers la population, estime Bernard Taverne. Ils nous apportent le point de vue des patients et peuvent jouer le rôle de lanceurs d’alerte en cas de dysfonctionnements du système de santé. Leur rôle est aujourd’hui reconnu par les autorités dans le domaine de la lutte contre le VIH mais pas dans les autres domaines. Il reste encore beaucoup de chemin à faire pour que la relation entre patients et professionnels de santé s’améliore dans les autres champs de la santé. »