Outils épidémiologiques pour l’étude de l’épilepsie en zone tropicale, intérêts et applications

Epilepsy is a common neurological disease encountered in 50 millions of people through the world, 80% of people with epilepsy are located in tropical countries. In developed countries, the study of epilepsy is done by register of population which permits to describe its distribution in general population. Sanitary, economic and political conditions of tropical countries don't permit this. Investigating epilepsy in tropical countries implies realization of surveys in general population. We studied the interest of various tools, for screening, for analyzing etiological factors and spatial localization, in order to produce the data needed for planning a program of action. Most of these tools can easily be employed and should contribute to improve the knowledge upon epilepsy in tropical countries.L'épilepsie est une pathologie neurologique fréquente présente chez près de 50 millions d'individus dans le monde, 80% d'entre eux se trouvent dans les pays tropicaux. Dans les pays industrialisés, l'étude de l'épilepsie est réalisée au moyen de registres de population qui permettent de décrire sa distribution en population générale. Les conditions sanitaires, économiques et politiques sous les latitudes tropicales ne le permettent pas. Afin d'étudier l'épilepsie dans les pays tropicaux il est nécessaire de réaliser des enquêtes en population générale. Nous avons étudié l'intérêt de différents outils permettant de produire les données nécessaires à la planification de programmes d'action adaptés, depuis le dépistage, les analyses étiologiques ainsi que leur représentation spatiale. La majorité des outils épidémiologiques étudiés, peuvent aisément être mis en place et devraient contribuer à améliorer la connaissance de l'épilepsie dans les pays tropicaux

Challenges of epidemiological research on epilepsy in resource-poor countries.

International audienceEpilepsy is one of the most common neurological disorders. Today, an estimated 50 million people live with epilepsy (PWE), 80% of whom in developing countries. The public health significance is particularly high in these settings because of its high prevalence, its seizure acuteness and frequency, and the sociological, psychosocial, and financial consequences for the households it affects

Diphtheria in Lao PDR: insufficient coverage or ineffective vaccine?

Background During late 2012 and early 2013 several outbreaks of diphthe-ria were notified in the North of the Lao People’s Democratic Republic. The aim of this study was to determine whether the re-emergence of this vaccine-preventable disease was due to insufficient vaccination coverage or reduction of vaccine effectiveness within the affected regions. Methods A serosurvey was conducted in the Huaphan Province on a cluster sampling of 132 children aged 12–59 months. Serum samples, socio-demographic data, nutri-tional status and vaccination history were collected when available. Anti-diphtheria and anti-tetanus IgG antibody levels were measured by ELISA. Results Overall, 63.6% of participants had detectable diphtheria antibodies and 71.2% tetanus antibodies. Factors independently associated with non-vaccination against diphtheria were the distance from the health centre (OR: 6.35 [95% CI: 1.4–28.8], p = 0.01), the Lao Theung ethnicity (OR: 12.2 [95% CI:1,74–85, 4], p = 0.01) and the lack of advice on vac-cination given at birth (OR: 9.8 [95% CI: 1.5–63.8], (p = 0.01) while the level of maternal edu-cation was a protective factor (OR: 0.08 [95% CI: 0.008–0.81], p = 0.03). Most respondents claimed financial difficulties as the main reason for non-vaccination. Out of 55 children whose vaccination certificates stated that they were given all 3 doses of diphtheria-containing vaccine, 83.6% had diphtheria antibodies and 92.7% had tetanus antibodies. Furthermore, despite a high prevalence of stunted and underweight children (53% and 25.8%, respectively), the low levels of anti-diphtheria antibodies were not correlated to the nutritional status. Conclusions Our data highlight a significant deficit in both the vaccination coverage and diphtheria vaccine effectiveness within the Huaphan Province. Technical defi-ciencies in the methods of storage and distribution of vaccines as well as unreliability of vac-cination cards are discussed. Several hypotheses are advanced to explain such a decline in immunity against diphtheria and recommendations are provided to prevent future outbreaks

Hepatitis B virus in the Lao People’s Democratic Republic: a cross sectional serosurvey in different cohorts

Background Despite hepatitis B vaccination at birth and at 6, 10 and 14 weeks of age, hepatitis B virus (HBV) infection continues to be endemic in the Lao People’s Democratic Republic (PDR). We carried out a cross-sectional serological study in infants, pre-school children, school pupils and pregnant women to determine their burden of disease, risk of infection and vaccination status. Methods A total of 2471 participants between 9 months and 46 years old were recruited from urban (Vientiane Capital, Luang Prabang), semi-urban (Boulhikhamxai and Savannakhet) and remote rural areas (Huaphan). All sera were tested for anti-HBs and anti-HBc. Sera testing positive for anti-HBc alone were further tested for the presence of HBsAg. Results A low prevalence of HBsAg (0.5%) was detected among infants from Vientiane and Luang Prabang, indicating some success of the vaccination policy. However, only 65.6% had protective anti-HBs antibodies, suggesting that vaccination coverage or responses remain sub-optimal, even in these urban populations. In pre-school children from remote areas in Huaphan, 21.2% were positive for anti-HBc antibodies, and 4.6% were for HBsAg positive, showing that a significant proportion of children in these rural regions have early exposure to HBV. In pre-school children with 3 documented HBV vaccinations, only 17.0% (15/55) were serologically protected. Among school-children from semi-urban regions of Luang Prabang, Boulhikhamxai and Savannakhet provinces, those below the age of 9 who were born after HBV vaccine introduction had anti-HBc and HBsAg prevalence of 11.7% and 4.1%, respectively. The prevalence increased to 19.4% and 7.8% of 10–14 year olds and to 27% and 10.2% of 15–19 year olds. Pregnant women from Luang Prabang and Vientiane had very high anti-HBc and HBsAg prevalence (49.5% and 8.2%), indicating high exposure and risk of onward vertical transmission to the unborn infant. Conclusions Overall, the results demonstrate a dramatic deficiency in vaccination coverage and vaccine responses and/or documentation within the regions of Lao PDR studied, which included urbanized areas with better health care access. Timely and effective hepatitis B vaccination coverage is needed in Lao PDR

The Disease Burden of Taenia solium Cysticercosis in Cameroon

Taenia solium cysticercosis is a zoonotic disease occurring in many developing countries. A relatively high prevalence in humans and pigs has been reported in several parts of the world, but insufficient data are available on the disease burden. Disease impact assessment needs detailed information on well-defined epidemiological and economic parameters. Our work conducted in West Cameroon over several years allowed us to collect the necessary information to estimate the impact of the parasite on the human and animal populations in this area using both cost and Disability Adjusted Life Year (DALY) estimations. This study identified the professional inactivity caused by the disease as the major loss factor in comparison to the cost of health care and losses due to infected pigs. These findings should allow a simpler estimation of the global disease burden based on information on salary levels and human cysticercosis prevalence in endemic areas of the world. In addition, the number of DALYs lost was higher than estimates already available for some other neglected tropical diseases in sub-Saharan Africa

Outils épidémiologiques pour l étude de l épilepsie en zone tropicale, intérêts et applications

L'épilepsie est une pathologie neurologique fréquente présente chez près de 50 millions d'individus dans le monde, 80% d'entre eux se trouvent dans les pays tropicaux. Dans les pays industrialisés, l'étude de l'épilepsie est réalisée au moyen de registres de population qui permettent de décrire sa distribution en population générale. Les conditions sanitaires, économiques et politiques sous les latitudes tropicales ne le permettent pas. Afin d'étudier l'épilepsie dans les pays tropicaux il est nécessaire de réaliser des enquêtes en population générale. Nous avons étudié l'intérêt de différents outils permettant de produire les données nécessaires à la planification de programmes d'action adaptés, depuis le dépistage, les analyses étiologiques ainsi que leur représentation spatiale. La majorité des outils épidémiologiques étudiés, peuvent aisément être mis en place et devraient contribuer à améliorer la connaissance de l'épilepsie dans les pays tropicaux.LIMOGES-BU Médecine pharmacie (870852108) / SudocSudocFranceF

Comment on "Epilepsy and seropositivity rates of Toxocara canis and Toxoplasma gondii".

International audienc