[Effects of Monitoring "Out-of-Area" Vaccinated Children on Data Quality, San Pedro Health District, Côte D'ivoire in 2019]. / Effets du Suivi des Enfants « Hors Zone ¼ Vaccinés sur la Qualité des Données, District Sanitaire de San Pedro, Côte D'ivoire, 2019.

In order to improve the quality of vaccination data from the health centers, we carried out the follow-up of "out-of-area" children, vaccinated in the district of San Pedro. The objective of this work was to measure the effects of taking into account the "out-of-area" vaccinated children on the quality of the data and the immunization performance of the health centers. This monitoring, which was carried out between March and August 2019, consisted of four steps: the vaccination of "out-of-area" children by the health center, the monthly update in the register of the status of vaccinated "out-of-area" children, the accounting of these children, and the re-evaluation of the health center's vaccine performance. A total of 37 of the 40 district centers had 980 "out-of-area" vaccinated children, representing 5.7% of the immunization target. The quarter of these children resided outside the district. The vaccination of "out-of-area" children included all EPI vaccines, but especially BCG, DTP-HepB-Hib and Pneumococcus_13. The number of "outside the extra-district area" vaccinated children had not changed the district's immunization coverage. On the other hand, in the health centers concerned, the accuracy of the data had been improved in 65% of the centers for DTP-HepB-Hib_1, in 70% of the centers for RR and in 65% of the centers for the overall immunization dropout rate. The approach used had made it possible to improve the quality of immunization data from health centers at no additional cost.

[Performance of the Strategy to Catch Up with Drop Out and Unvaccinated Children in Côte d'Ivoire in 2018]. / Performance de la stratégie de rattrapage des enfants perdus de vue et non vaccinés en Côte d'Ivoire en 2018.

To improve the performance of Côte-d'Ivoire's immunization program, we have implemented a strategy to catch up with drop out children (DOC) and unvaccinated children (UVC) in 14 Health Districts (HDs) with the lowest measles vaccination coverage. This article presents the effectiveness and cost of this strategy. We selected the areas with the highest numbers of DOC: 5 health areas (HAs) per HD and 5 villages/neighborhoods per HA. The strategy, which was implemented by civil society organizations, health centre managers (HCMs) and community health workers (CHWs), combined sensitization of community leaders and groups, home visits (HV) and referral of children to the HCs for immunization. Out of the 17,912 reported DOC, 9,425 found (52.6%) and 8,245 were vaccinated (46% of declared, 87.5% of found). The HCMs reported 484 UVC while the home visits identified 1,315 of which 1,087 were vaccinated (82.7%). Out of a total declared number of 18,396 children to be caught up, 10,740 found (58.4%) and 9,332 vaccinated, i.e. 50.8% (9,332/18,396) of children to be caught up and 86.9% (9,332/10,740) of children found. The total specific recurrent cost of the strategy was XOF 22,375,008, with XOF 2,083 (22,375,008/10,740) per child found and XOF 2,398 (22,375,009/9,332) per child found and vaccinated. In view of these results, this strategy should be implemented in all of the country's low-performing HDs.

Pour améliorer la performance du programme élargi de vaccination de Côte d'Ivoire, nous avons mis en place une stratégie de rattrapage des enfants perdus de vue (EPDV) et des enfants non vaccinés (ENV) dans les 14 districts sanitaires (DS) ayant les plus faibles couvertures vaccinales antirougeoleuses. Cet article présente l'efficacité et le coût de cette stratégie. Nous avons retenu les localités ayant les plus grands nombres d'EPDV : cinq aires de santé (AS) par DS et cinq villages/quartiers par AS. La stratégie qui a été mise en oeuvre par les organisations de la société civile, les responsables des centres de santé (RCS) et les agents de santé communautaire a combiné la sensibilisation des leaders et groupes communautaires, les visites à domicile (VAD) et la référence des enfants aux CS pour la vaccination. Sur les 17 912 EPDV déclarés, 9 425 ont été retrouvés (52,6 %) et 8 245 vaccinés (46 % des déclarés et 87,5 % des retrouvés). Les RCS ont déclaré 484 ENValors que les VAD ont permis d'en identifier 1 315 dont 1 087 ont été vaccinés (82,7 %). Sur un nombre total déclaré de 18 396 enfants à rattraper, 10 740 ont été retrouvés (58,4 %) et 9 332 vaccinés, soit 50,8 % (9 332/18 396) d'enfants à rattraper et 86,9 % (9 332/10 740) d'enfants retrouvés. Le coût récurrent spécifique total de la stratégie était de 22 375 008 FCFA, soit 2 083 FCFA (22 375 008/10 740) par enfant retrouvé et 2 398 FCFA (22 375 008/9 332) par enfant retrouvé et vacciné. Au vu de ces résultats, cette stratégie devrait être mise en oeuvre dans tous les DS à faible performance du pays.

Effects of climatological parameters in modeling and forecasting seasonal influenza transmission in Abidjan, Cote d'Ivoire.

BACKGROUND: In temperate regions, influenza epidemics occur in the winter and correlate with certain climatological parameters. In African tropical regions, the effects of climatological parameters on influenza epidemics are not well defined. This study aims to identify and model the effects of climatological parameters on seasonal influenza activity in Abidjan, Cote d'Ivoire. METHODS: We studied the effects of weekly rainfall, humidity, and temperature on laboratory-confirmed influenza cases in Abidjan from 2007 to 2010. We used the Box-Jenkins method with the autoregressive integrated moving average (ARIMA) process to create models using data from 2007-2010 and to assess the predictive value of best model on data from 2011 to 2012. RESULTS: The weekly number of influenza cases showed significant cross-correlation with certain prior weeks for both rainfall, and relative humidity. The best fitting multivariate model (ARIMAX (2,0,0) _RF) included the number of influenza cases during 1-week and 2-weeks prior, and the rainfall during the current week and 5-weeks prior. The performance of this model showed an increase of >3 % for Akaike Information Criterion (AIC) and 2.5 % for Bayesian Information Criterion (BIC) compared to the reference univariate ARIMA (2,0,0). The prediction of the weekly number of influenza cases during 2011-2012 with the best fitting multivariate model (ARIMAX (2,0,0) _RF), showed that the observed values were within the 95 % confidence interval of the predicted values during 97 of 104 weeks. CONCLUSION: Including rainfall increases the performances of fitted and predicted models. The timing of influenza in Abidjan can be partially explained by rainfall influence, in a setting with little change in temperature throughout the year. These findings can help clinicians to anticipate influenza cases during the rainy season by implementing preventive measures.

[Entomological evaluation of the risk of urban outbreak of yellow fever in 2008 in Abidjan, Côte d'Ivoire]. / Évaluation entomologique du risque d'épidémie urbaine de fièvre jaune survenue en 2008 dans le district d'Abidjan, Côte d'Ivoire.

In April 2008, seven years after the outbreak of 2001, Abidjan faced another epidemic of yellow fever. Three weeks after the case detected in the commune of Treichville at 28(th) of April 2008, two other cases were notified, the first one in Port-Bouet and the second one in Cocody located respectively in the south and north of the city of Abidjan. In order to determine a large-scale risk of urban yellow fever epidemic, epidemiological and entomological investigations were conducted by the Ministry of Health and Public Hygiene of Cote d'Ivoire with the support of the Global Outbreak Alert and Response Network. Entomological investigations revealed the predominance of Aedes ægypti, urban vector of yellow fever in neighborhood visited with larval density indices between 2 and 5, indicating the existence of a sufficient density of the vector for cause an explosion of the epidemic. In fact, the massive influx of people from inside cities towards Abidjan caused by the socio-political crisis occurred in the country in 2002, the deterioration of environment with the creation of more breeding sites of Ae. ægypti as corollary and the circulation of the virus at mosquito level were many factors favorable to the yellow fever outbreak in Abidjan city.

[Entomological investigations conducted around ten cases of yellow fever in 2009 in the Denguélé sanitary region, Côte-d'Ivoire]. / Investigations entomologiques menées autour de dix cas de fièvre jaune survenus en 2009 dans la région sanitaire du Denguélé, Côte-d'Ivoire.

In November 2009, ten suspicious cases of yellow fever, including six deaths, were notified in the region of Denguélé, in the northwest of Côte-d'Ivoire. In order to evaluate the extent of yellow fever virus circulation and the risk for local people, a mission of entomological investigation was carried out by the Ministry of Health and Public Hygiene of Côte-d'Ivoire. Entomological investigations were conducted in the villages of confirmed cases (Banakoro and Tron-Touba) and the centers of consultation and hospitalization of cases during illness. Breteau index and recipient index were quasi nil. Aedes aegypti was absent among the captured mosquitoes. On the other hand, Aedes luteocephalus and Aedes opok were present at Banakoro and Tron-Touba with respective average biting rates of 0.8 and 0.6 bite/man/twilight. This situation of epidemic in the northwest of Côte-d'Ivoire could be explained by the deterioration of Denguélé region's health system which is a consequence of the war started in the country in 2002 and which has lowered the immunity of the population.

Effectiveness of hepatitis-B vaccination in Ivory Coast: the case of the Grand Bassam health district.

Ivory Coast has a high prevalence of infection with hepatitis B virus (HBV). The effects of a control programme based on the anti-HBV vaccine, which has formed part of the national Expanded Programme on Immunization (EPI) since 2000, have recently been evaluated in the country, for the first time. In this, cross-sectional investigation, two-stage cluster sampling stratified by age was used to assess the impact of the programme of universal childhood HBV vaccination in the Grand Bassam health district. The seroprevalences of carriage of the HBV surface antigen (HBsAg) and of antibodies to this antigen (HBsAb) and to the core antigen of HBV (HBcAb) were estimated among children aged 12-59 months and their mothers. Serology was successful for 1038 children (of 1172 in the original sample) and 836 mothers. Of the children enrolled, 46.8% had had a standard vaccination (completed before the age of 6 months, with the correct schedule), 4.6% had had no vaccination against HBV, and the rest had received incomplete or incorrectly timed vaccination. The prevalence of HBsAg carriage was 0.7% among the tested children and 9.9% among the tested mothers. The prevalence of seroprotection (i.e. an HBsAb titre of >10 mIU/ml), which was 74.2% overall, was strongly correlated with the number of vaccination doses, ranging from 16.7% in the unvaccinated infants to 85.5% in the children who had each received four doses. Circulation of the virus (indicated by seropositivity for HBcAb) was much higher among the unvaccinated children (10.4%) than the fully vaccinated ones (2.9%). The prevalences of both HBsAg and HBcAb were higher in rural areas, where vaccine coverage was relatively low, than in the urban areas. It appears that HBV vaccine is highly effective within the framework of the EPI in Ivory Coast, where it has already had a positive impact in reducing HBsAg carriage among children under 5 years of age. Improving vaccination coverage in the rural areas of the country is now a public-health priority.

[Entomological investigation following the re-emergence of yellow fever in 2008 in Abidjan area (Côte d'Ivoire)]. / Investigation entomologique à la suite de la réémergence de la fièvre jaune en 2008 à Abidjan (Côte d'Ivoire).

In April 2008, Abidjan was again faced with another case of yellow fever after the epidemic of 2001 causing mass immunization campaign. In order to evaluate the extent of amaril virus circulation and the risk for local people, an entomological investigation was carried out by the Ministry of Health and Public Hygiene of Côte d'Ivoire. At "Entent" area of Treichville, Breteau index was estimated at 34, recipient index at 20% and house index at 25%. Those indexes were respectively 53, 21 and 31% at "Vridi canal" of Port Bouet. In the both neighborhood, Aedes aegypti accounted for more than 80% of mosquitoes caught and more than 90% of mosquitoes adults obtained from larval breeding. This new situation of epidemic risk could be explained by several factors including the reception of 70% of forced migration people caused by the crisis in the country occurred in 2002, the probable drop of preventive immunization, the environment deterioration creating of more breeding sites of Ae. aegypti.

[Five years of cholera surveillance in Ivory Coast during social and political crisis, 2001 to 2005]. / Cinq années de surveillance du choléra en Côte d'Ivoire dans un contexte de crise socio-politique, 2001 à 2005.

For an efficient struggle against infectious diseases with epidemic potential, the Cdte d'Ivoire set up a precocious alert system in 2001 with a main objective: to detect epidemics of cholera, measles, yellow fever and meningitis and to provide necessary information for their control and their prevention. During the 2001 to 2005 period, the country was marked by military and political crisis which occurred in 2002; the country had to face up to a reappearance of cholera. How did it evolve in such a context? The question was to describe the performances of the system and the evolution of cholera from weekly data collected by the centers of epidemiological monitoring in health districts. The cases and declared deaths were compiled and the indicators of morbidity and mortality were then studied according to time site and individual features on the period of 2001 to 2005. From 2001 to 2005, 11,874 cases were notified with 564 deaths and a lethal rate of 4.7%. In 2001, from the initial source of infection, the civil jail, the epidemic of cholera disseminated itself through visitors in the whole city of Abidjan where 3250 cases were notified. Out of city, 20 outbreaks have been declared with a total of 3010 cases. The yearly highest impact, 37 living cases/100,000 inhabitants recorded in 2001, decreased regularly until 2005 with 0.2 living cases/100,000. After 2002, outbreaks were located mainly in the half south of the country which welcomed displaced populations from the north, preferably in transition or settling zones near the front line. The lethal rate in Abidjan (2.3%) was less important than that of other health districts (8.6%). The lethal rate globally increased as the impact decreased. Vibrio cholerae was responsible for the epidemics. The group of 15 years old and over was the most affected (12.69 living cases/100,000) whereas the highest lethal rate appeared in the group under 5 years old (6.6%). The reappearance and constant cholera epidemics in Côte d'Ivoire are due to bad general hygiene conditions, insufficient supply of drinking water from wells or packaged, concentration of populations in the south of the country due to war and uncontrolled development of the poor and unsanitary precarious boroughs. Outburst during the dry season is a warning signal of an important epidemic during the raining season especially in poor urban areas. The precocious alert system has permitted to detect the epidemics, to follow up their evolution and to orientate the struggle against cholera in Côte d'Ivoire.

[Detection and management of the yellow fever epidemic in the Ivory Coast, 2001]. / Detection et gestion de l'epidemie de fievre jaune en Cote d'Ivoire, 2001.

From March to December 2001, an outbreak of yellow fever was observed in Cote d'Ivoire. Sentinel surveillance for hemorrhagic fever allowed detection of the first case in the Duekoue health district in the heavily wooded western part of the country. A weekly reporting system was established. For each suspected case recorded and reported to the Epidemiological Surveillance Department at the National Institute of Public Hygiene, a sample was collected and sent for confirmation at the Pasteur Institute of the Cote d'Ivoire. The outbreak progressed from West to East reaching Abidjan, the economic capital of the country located in the southeast. The epidemic emergency plan consisted of setting up a crisis committee to implement epidemiological, entomological and virological surveillance, mass vaccination campaigns in areas around confirmed cases, and vector control. A total of 280 cases were reported including 32 confirmed cases and 6 deaths. Eleven out of 62 districts were affected with most cases occurring in cities with more than 10000 inhabitants. Over 3.7 million persons were vaccinated for an overall coverage of 92.2% in the areas where campaigns were carried out. As a result of this outbreak, surveillance for potentially epidemic diseases has been reinforced and surveillance of viral transmission is now being considered. A vaccination program for adults has also been established.