Pr. Mouhaman Arabi | University of Maroua (Cameroon) (original) (raw)
Papers by Pr. Mouhaman Arabi
In the specialized literature, urban risk is defined in a very simple way, as the risk linked to ... more In the specialized literature, urban risk is defined in a very simple way, as the risk linked to the territory of the city. In this study, we study the risks that have arisen in the city of Maroua, capital of the Far North Region of Cameroon. The realization of this study mobilized both factual and geo-historical data. Simple descriptive statistical analyzes were then performed. According to the archives available from the various administrations, the oldest documented disaster in the city of Maroua dates back to 1991, mainly floods, epidemics of meningitis and cholera. We note that traffic accidents and fires, which generally take place in very specific neighborhoods and on very specific axes, come first with 831 and 604 cases respectively. In addition, the documentation of catastrophic events is still very poor, because it does not allow an assessment of their real impacts, and no social disaster such as generalized fights or interethnic conflicts has been reported in the city despite its cosmopolitan character.
This work was conducted to evaluate water and sediments pollution parameters of the Chari River a... more This work was conducted to evaluate water and sediments pollution parameters of the Chari River around Mani according to the seasons (dry and
rain). Samples were taken and underwent necessary treatments by mineralization before their analyses by spectrophotometry of molecular
absorption (SAM) in the laboratory. The statistical Analysis of the data in Principal Components (ACP) was conducted to detect correlations
between the various studied parameters and their sources of pollution. The physicochemical characterization of water samples showed that they
are slightly mineral-bearing (average conductivity 96,68 μS/cm) with a value of pH which extends from (6,83±0,03) to (8,09±0,01) and that of the
dissolved oxygen which varies between (3,23±0,30) mg/L and (7,45±1,47) mg/L. The report DCO/DBO5 which lies between 2,97 and 4,29 shows
that the water of river Chari is charged with the matters not easily biodegradable. As for the mineral matters, the sulfate ions which stand out from
the rest (NH4+; NO2- ; NO3- ; PO43 -) vary from (9,66 ± 0,57) mg/L to (16 ± 0,00) mg/L. The obtained contents of studied heavy metals (Fe,
Cr, Pb, Cd and As) are higher than the standards of WHO. The contents are higher in the dry season than in the rainy season. Indeed, the increase
in the temperature in dry season involves a parallel increase in dissolved ions by the phenomenon of evaporation. In the analysis of the sediments,
the highest contents of the major ions are respectively: (6,00±0,10) Mg/kg for NH4+ ; (7,40±0,08) mg/kg for NO2- ; (11,20±0,13) mg/kg for NO3-
; (7,96±0,83) for PO43- and (443,30±1,52) for SO42- .As for studied heavy metals, the results obtained of the calculation of the index of
Contamination (IC), which varies from 0,002 to 1, 61 and that of the index of Total Contamination (ICm) varies from 0, 43 to 0, 75, reflect the
absence of metal contamination of the sediments.
Key words: Chad, Chari River, Mani, pollution, water, sediments.
When refugees flee their homes due to civil strife or natural disasters, their condition on arriv... more When refugees flee their homes due to civil strife or natural disasters, their condition on arrival can vary dramatically. Gastro-intestinal infections are a common cause of illness in refugee camps because of factors associated with hygiene, sanitation as well as nutrition and crowding. The study was conducted to understand the conditions of access to water and sanitation in the light of international standards. A total of one hundred and fifty (150) households were surveyed within the camp. Dumpsites and boreholes within the camp were georeferenced and mapped. A simple descriptive approach was used to analyse the data and the findings were compared to international standards. A total of 31 boreholes unevenly distributed were found in the camp. The average volume of water available per person per day was 12.5 liters less than the standard of 15 litter in emergency situation. There were 24 dumpsites available in the camp but only 58 % of the dumpsites are fully functional and used. There were close to 2, 800 latrines in the camp of two main types, namely personal latrines constructed by the refugees themselves and collective latrines constructed by relief agencies. The average number of people in the camp is much greater than the standard recommended of 20 people per toilet facility. The study also revealed that the state of the latrines had a great impact on the behaviour of people towards latrines. On a general note, it appears that open air defecation is still a matter of concern in the camp. Whatever the case, there is a need to balance the number of boreholes and construct more latrines in order to meet the standards.
Locally measured variables such as temperature and rainfall have been positively associated with ... more Locally measured variables such as temperature and rainfall have been positively associated with increased cholera incidence in multiple studies. The study examined the effect of rainfall, temperature and relative humidity on cholera incidence in the City of Maroua, located in the Far North of Cameroon. The relative individual contribution of rainfall, temperature and humidity and then their combined contribution on the occurrence of cholera were examined. Using monthly time series of cholera epidemiological data, average monthly rainfall (mm), average monthly air temperature (degree Celsius), and average monthly relative humidity (percent) data from 1996 to 2011.We implemented Generalized Additive Modeling (GAM) procedures to measure the contribution of each weather parameter to the incidence of cholera and identified the most influential parameter on cholera incidence. We found that taken individually, rainfall, temperature and humidity are correlated with cholera incidence but temperature seems more determinant since it has a higher deviance explained (26%). Furthermore, the association between temperature and rainfall in the multivariate model with interaction has the highest deviance explained is 64.4%, the lowest AIC is 1911.963, and the highest R 2 (0.6). These results indicate that statistical time series models in general and the Generalized Additive models in particular should lead to a better understanding of the disease mechanism that can assist in the planning of public health interventions. These results contribute also to the growing debate on climate and cholera.
Revue d'élevage et de médecine vétérinaire des pays tropicaux, 2019
An entomological study was carried out in the Far North region of Cameroon – historically known f... more An entomological study was carried out in the Far North region of Cameroon – historically known focus for animal trypanosomosis and declared tsetse free in the late 1970s – to determine the potential mechanical vectors for trypanosomes and their spatial preference in this region. Thirty-one Nzi traps were installed at 6:30–8:00 a.m. in Goulfey, Madiako canton and Darack karena in Logone and Chari Division, as well as in Guidiguis, Kalfou and Maga-Guirvidig in two other divisions. They were visited after 10–11 hours of exposition. The sampling lasted one day. A total of 20,084 hematophagous flies (865 Stomoxys and 19,219 tabanids) were collected. Stomoxys niger was the only Stomoxyinae species caught, whereas five species of tabanids were collected: Atylotus agrestis , A. albipalpus , A. fuscipes , Tabanus taeniola and T. biguttatus . A. agrestis was by far the most prevalent species (92.7%), followed by T. taeniola (7.1%). The apparent densities of 50.1, 409.4 and 1499.0 tabanids pe...
Revue d’élevage et de médecine vétérinaire des pays tropicaux, 2019
Une étude entomologique a été menée dans la région de l’Extrême-Nord du Cameroun – foyer historiq... more Une étude entomologique a été menée dans la région de l’Extrême-Nord du Cameroun – foyer historiquement connu pour la trypanosomose animale et déclaré exempt de glossines à la fin des années 1970 – afin de déterminer les vecteurs mécaniques potentiels des trypanosomes et leur préférence spatiale dans cette région. Trente et un pièges Nzi ont été installés le matin (6 h 30 – 8 h 00) à Goulfey, Madiako canton, Darack Karena dans le département de Logone et Chari, ainsi qu’à Guidiguis, Kalfou et Maga-Guirvidig dans deux autres départements. Ils ont été inspectés après 10 à 11 heures d’exposition. L’échantillonnage a duré un jour. Au total 20 084 mouches hématophages (865 Stomoxys et 19 219 tabanidés) ont été récoltées. Stomoxys niger a été la seule espèce de Stomoxyinae capturée, alors que cinq espèces de tabanidés ont été relevées : Atylotus agrestis, A. albipalpus, A. fuscipes, Tabanus taeniola et T. biguttatus. A. agrestis était de loin l’espèce la plus répandue (92,7 %), suivie de ...
Revue d'élevage et de médecine vétérinaire des pays tropicaux, 2019
An entomological study was carried out in the Far North region of Cameroon – historically known f... more An entomological study was carried out in the Far North region of Cameroon – historically known focus for animal trypanosomosis and declared tsetse free in the late 1970s – to determine the potential mechanical vectors for trypanosomes and their spatial preference in this region. Thirty-one Nzi traps were installed at 6:30–8:00 a.m. in Goulfey, Madiako canton and Darack karena in Logone and Chari Division, as well as in Guidiguis, Kalfou and Maga-Guirvidig in two other divisions. They were visited after 10–11 hours of exposition. The sampling lasted one day. A total of 20,084 hematophagous flies (865 Stomoxys and 19,219 tabanids) were collected. Stomoxys niger was the only Stomoxyinae species caught, whereas five species of tabanids were collected: Atylotus agrestis , A. albipalpus , A. fuscipes , Tabanus taeniola and T. biguttatus . A. agrestis was by far the most prevalent species (92.7%), followed by T. taeniola (7.1%). The apparent densities of 50.1, 409.4 and 1499.0 tabanids pe...
Journal of Vector Borne Diseases, 2017
Background & objectives: The Far-North region of Cameroon has been considered free of tsetse ... more Background & objectives: The Far-North region of Cameroon has been considered free of tsetse and trypanosomiasis for the past three decades. But recent reports by pastoralists indicate its reappearance in the region. This study was aimed to confirm the existence of cattle trypanosomiasis and determine its prevalence, and to establish pastoralists knowledge and practice (KP) of the disease in Ndiyam Shinwa pastoral zone of Cameroon. Methods: A total of 118 herds were surveyed for a descriptive, cross-sectional study in Ndiyam Shinwa pastoral zone from May to November 2014. Out of these, 110 herds were visited in the beginning of the rainy season, 22 of the 110 herds (suspect cattle) were revisited along with the remaining eight herds in the end of the season. The blood samples of 635 suspect cattle and 135 nonsuspect cattle were collected. Samples were subjected to two diagnostic tests: Buffy coat test (BCT) and packed cell volume (PCV) determination. A survey on pastoralist’s (n = 118) KP about trypanosomiasis was also undertaken. Results: Parasitological analyses revealed six infections by Trypanosoma vivax: Four in suspect cattle against two in nonsuspect cattle, corresponding respectively to apparent prevalence of 0.63 and 1.46% and true prevalence of (0.79–3.15%) and (1.82–7.30%). The proportion of cattle found infected in the PCV as well as BCT tests was 33.26% for suspect cattle. More than 75% of followed-up suspects showed persisting symptoms nearly three months after initial examination. The most common diagnostic signs for pastoralists were ruffled hair, lacrimation, anorexia and emaciation. Interpretation & conclusion: Cattle trypanosomiasis has reappeared in the Far-North region and seems to be in the inter-epizootic phase. Pastoralists have a good knowledge of the disease, but their perception of its importance seems to be influenced by the persistence of symptoms attributed to this disease in suspect cattle.
Geographia Technica, 2019
Locally measured variables such as temperature and rainfall have been positively associated with ... more Locally measured variables such as temperature and rainfall have been positively associated with increased cholera incidence in multiple studies. The study examined the effect of rainfall, temperature and relative humidity on cholera incidence in the City of Maroua, located in the Far North of Cameroon. The relative individual contribution of rainfall, temperature and humidity and then their combined contribution on the occurrence of cholera were examined. Using monthly time series of cholera epidemiological data, average monthly rainfall (mm), average monthly air temperature (degree Celsius), and average monthly relative humidity (percent) data from 1996 to 2011.We implemented Generalized Additive Modeling (GAM) procedures to measure the contribution of each weather parameter to the incidence of cholera and identified the most influential parameter on cholera incidence. We found that taken individually, rainfall, temperature and humidity are correlated with cholera incidence but temperature seems more determinant since it has a higher deviance explained (26%). Furthermore, the association between temperature and rainfall in the multivariate model with interaction has the highest deviance explained is 64.4%, the lowest AIC is 1911.963, and the highest R 2 (0.6). These results indicate that statistical time series models in general and the Generalized Additive models in particular should lead to a better understanding of the disease mechanism that can assist in the planning of public health interventions. These results contribute also to the growing debate on climate and cholera.
Cholera is an acute infection caused by ingestion of food or water contaminated with the bacteriu... more Cholera is an acute infection caused by ingestion of food or water contaminated with the bacterium Vibrio cholerae. We used cholera epidemics data from 1996 to 2011 to describe the geographical pattern of cholera incidence in the Far North. The incidence rate of cholera per 10 000 persons and the cumulative incidence rate of the various epidemics were computed for each of the health districts. The data were entered into a GIS for visualisation and mapping. This study shows that cholera outbreak followed a specific spatial pattern and that GIS mapping can be useful to health services. Résumé: Le choléra est une infection aiguë causée par l'ingestion d'aliments ou d'eau contaminés par la bactérie Vibrio cholerae. Nous avons utilisé les données des épidémies de choléra de 1996 à 2011 pour décrire la répartition géographique de l'incidence du choléra dans l'Extrême Nord. Le taux d'incidence du choléra pour 10 000 personnes et le taux d'incidence cumulé des di...
Revue d’élevage et de médecine vétérinaire des pays tropicaux, 2019
Une étude entomologique a été menée dans la région de l’Extrême-Nord du Cameroun – foyer historiq... more Une étude entomologique a été menée dans la région de l’Extrême-Nord du Cameroun – foyer historiquement connu pour la trypanosomose animale et déclaré exempt de glossines à la fin des années 1970 – afin de déterminer les vecteurs mécaniques potentiels des trypanosomes et leur préférence spatiale dans cette région. Trente et un pièges Nzi ont été installés le matin (6 h 30 – 8 h 00) à Goulfey, Madiako canton, Darack Karena dans le département de Logone et Chari, ainsi qu’à Guidiguis, Kalfou et Maga-Guirvidig dans deux autres départements. Ils ont été inspectés après 10 à 11 heures d’exposition. L’échantillonnage a duré un jour. Au total 20 084 mouches hématophages (865 Stomoxys et 19 219 tabanidés) ont été récoltées. Stomoxys niger a été la seule espèce de Stomoxyinae capturée, alors que cinq espèces de tabanidés ont été relevées : Atylotus agrestis, A. albipalpus, A. fuscipes, Tabanus taeniola et T. biguttatus. A. agrestis était de loin l’espèce la plus répandue (92,7 %), suivie de ...
Résumé Les migrations sont au cur des questions de développement en Afrique centrale à cause d... more Résumé Les migrations sont au cur des questions de développement en Afrique centrale à cause de l'augmentation de la population et de la situation économique délétère. C'est dans cette perspective que les Etats de la sous-région ont tenté d'encadrer les migrations. ...
Journal of Vector Borne Diseases, 2017
Background & objectives: The Far-North region of Cameroon has been considered free of tsetse ... more Background & objectives: The Far-North region of Cameroon has been considered free of tsetse and trypanosomiasis for the past three decades. But recent reports by pastoralists indicate its reappearance in the region. This study was aimed to confirm the existence of cattle trypanosomiasis and determine its prevalence, and to establish pastoralists knowledge and practice (KP) of the disease in Ndiyam Shinwa pastoral zone of Cameroon. Methods: A total of 118 herds were surveyed for a descriptive, cross-sectional study in Ndiyam Shinwa pastoral zone from May to November 2014. Out of these, 110 herds were visited in the beginning of the rainy season, 22 of the 110 herds (suspect cattle) were revisited along with the remaining eight herds in the end of the season. The blood samples of 635 suspect cattle and 135 nonsuspect cattle were collected. Samples were subjected to two diagnostic tests: Buffy coat test (BCT) and packed cell volume (PCV) determination. A survey on pastoralist’s (n = 118) KP about trypanosomiasis was also undertaken. Results: Parasitological analyses revealed six infections by Trypanosoma vivax: Four in suspect cattle against two in nonsuspect cattle, corresponding respectively to apparent prevalence of 0.63 and 1.46% and true prevalence of (0.79–3.15%) and (1.82–7.30%). The proportion of cattle found infected in the PCV as well as BCT tests was 33.26% for suspect cattle. More than 75% of followed-up suspects showed persisting symptoms nearly three months after initial examination. The most common diagnostic signs for pastoralists were ruffled hair, lacrimation, anorexia and emaciation. Interpretation & conclusion: Cattle trypanosomiasis has reappeared in the Far-North region and seems to be in the inter-epizootic phase. Pastoralists have a good knowledge of the disease, but their perception of its importance seems to be influenced by the persistence of symptoms attributed to this disease in suspect cattle.
The Pan African medical journal, 2017
In recent years, the Far North Region of Cameroon has experienced serious and recurrent cholera o... more In recent years, the Far North Region of Cameroon has experienced serious and recurrent cholera outbreaks. Yet, understanding of cultural influences on outbreaks and spread remain poorly understood. This qualitative study explored cultural influences on cholera exposure in this region. Interviews and group discussions were conducted in two phases. Phase I involved key informants and phase II included focus group and household discussions. Thematic techniques including word repetition, key-indigenous-terms, and key-words-in-context were used for qualitative data analysis. Key informants attributed cholera etiology to dirt and spread through water () and food (group eating or ) while group discussions attributed it to a reprimand from and transmission through the air. Participants suggested that funerals, weddings, open defecation, and mountaintop burial might influence cholera exposure and facilitate its spread. Hospital avoidance and non-adherence with cholera treatment regimens wer...
International journal of environmental research and public health, Apr 20, 2017
The Far North region in Cameroon has been more heavily impacted by cholera than any other region ... more The Far North region in Cameroon has been more heavily impacted by cholera than any other region over the past decade, but very little has been done to study the drivers of waterborne diseases in the region. We investigated the relationship between water, sanitation, and hygiene (WASH) parameters, microbial and antibiotic resistance (AR) contamination levels in drinking water, and health outcomes using health survey and molecular analysis during June and July of 2014 in two settlement types (agro-pastoralist villages and transhumant pastoralist camps). Quantitative polymerase chain reaction was used to determine fecal contamination sources, enteric pathogens, and antibiotic resistance genes. Ruminant-associated fecal contamination was widespread in both settlement types (81.2%), with human-associated contamination detected in 21.7% of the samples. Salmonella spp. (59.4%) and Shiga toxin-producing E. coli (stx1 44.9% and stx2 31.9%) were detected across all samples. Tetracycline resi...
PLoS neglected tropical diseases, 2016
Recurrent cholera outbreaks have been reported in Cameroon since 1971. However, case fatality rat... more Recurrent cholera outbreaks have been reported in Cameroon since 1971. However, case fatality ratios remain high, and we do not have an optimal understanding of the epidemiology of the disease, due in part to the diversity of Cameroon's climate subzones and a lack of comprehensive data at the health district level. A unique health district level dataset of reported cholera case numbers and related deaths from 2000-2012, obtained from the Ministry of Public Health of Cameroon and World Health Organization (WHO) country office, served as the basis for the analysis. During this time period, 43,474 cholera cases were reported: 1748 were fatal (mean annual case fatality ratio of 7.9%), with an attack rate of 17.9 reported cases per 100,000 inhabitants per year. Outbreaks occurred in three waves during the 13-year time period, with the highest case fatality ratios at the beginning of each wave. Seasonal patterns of illness differed strikingly between climate subzones (Sudano-Sahelian,...
From Data to Knowledge to Healthcare Improvement, 2016
Journal of Water and Health, 2016
This study examined the spatial variation of potential gastrointestinal pathogens within drinking... more This study examined the spatial variation of potential gastrointestinal pathogens within drinking water sources and home storage containers in four neighborhoods in Maroua, Cameroon. Samples were collected from source (n= 28) and home containers (n= 60) in each study neighborhood. Pathogen contamination was assessed using quantitative polymerase chain reaction, targeting Campylobacter spp., Shiga toxin producing Escherichia coli (virulence genes, stx1 and stx2), and Salmonella spp. Microbial source tracking (MST) targeted three different host-specific markers: HF183 (human), Rum2Bac (ruminant) and GFD (poultry) to identify contamination sources. Staphylococcus aureus and the tetracycline-resistance gene (tetQ) were assessed to measure human hand contact and presence of antibiotic-resistant bacteria. Pathogen/MST levels were compared statistically and spatially, and neighborhood variation was compared with previously collected demographic information. All the test fecal markers and p...
In the specialized literature, urban risk is defined in a very simple way, as the risk linked to ... more In the specialized literature, urban risk is defined in a very simple way, as the risk linked to the territory of the city. In this study, we study the risks that have arisen in the city of Maroua, capital of the Far North Region of Cameroon. The realization of this study mobilized both factual and geo-historical data. Simple descriptive statistical analyzes were then performed. According to the archives available from the various administrations, the oldest documented disaster in the city of Maroua dates back to 1991, mainly floods, epidemics of meningitis and cholera. We note that traffic accidents and fires, which generally take place in very specific neighborhoods and on very specific axes, come first with 831 and 604 cases respectively. In addition, the documentation of catastrophic events is still very poor, because it does not allow an assessment of their real impacts, and no social disaster such as generalized fights or interethnic conflicts has been reported in the city despite its cosmopolitan character.
This work was conducted to evaluate water and sediments pollution parameters of the Chari River a... more This work was conducted to evaluate water and sediments pollution parameters of the Chari River around Mani according to the seasons (dry and
rain). Samples were taken and underwent necessary treatments by mineralization before their analyses by spectrophotometry of molecular
absorption (SAM) in the laboratory. The statistical Analysis of the data in Principal Components (ACP) was conducted to detect correlations
between the various studied parameters and their sources of pollution. The physicochemical characterization of water samples showed that they
are slightly mineral-bearing (average conductivity 96,68 μS/cm) with a value of pH which extends from (6,83±0,03) to (8,09±0,01) and that of the
dissolved oxygen which varies between (3,23±0,30) mg/L and (7,45±1,47) mg/L. The report DCO/DBO5 which lies between 2,97 and 4,29 shows
that the water of river Chari is charged with the matters not easily biodegradable. As for the mineral matters, the sulfate ions which stand out from
the rest (NH4+; NO2- ; NO3- ; PO43 -) vary from (9,66 ± 0,57) mg/L to (16 ± 0,00) mg/L. The obtained contents of studied heavy metals (Fe,
Cr, Pb, Cd and As) are higher than the standards of WHO. The contents are higher in the dry season than in the rainy season. Indeed, the increase
in the temperature in dry season involves a parallel increase in dissolved ions by the phenomenon of evaporation. In the analysis of the sediments,
the highest contents of the major ions are respectively: (6,00±0,10) Mg/kg for NH4+ ; (7,40±0,08) mg/kg for NO2- ; (11,20±0,13) mg/kg for NO3-
; (7,96±0,83) for PO43- and (443,30±1,52) for SO42- .As for studied heavy metals, the results obtained of the calculation of the index of
Contamination (IC), which varies from 0,002 to 1, 61 and that of the index of Total Contamination (ICm) varies from 0, 43 to 0, 75, reflect the
absence of metal contamination of the sediments.
Key words: Chad, Chari River, Mani, pollution, water, sediments.
When refugees flee their homes due to civil strife or natural disasters, their condition on arriv... more When refugees flee their homes due to civil strife or natural disasters, their condition on arrival can vary dramatically. Gastro-intestinal infections are a common cause of illness in refugee camps because of factors associated with hygiene, sanitation as well as nutrition and crowding. The study was conducted to understand the conditions of access to water and sanitation in the light of international standards. A total of one hundred and fifty (150) households were surveyed within the camp. Dumpsites and boreholes within the camp were georeferenced and mapped. A simple descriptive approach was used to analyse the data and the findings were compared to international standards. A total of 31 boreholes unevenly distributed were found in the camp. The average volume of water available per person per day was 12.5 liters less than the standard of 15 litter in emergency situation. There were 24 dumpsites available in the camp but only 58 % of the dumpsites are fully functional and used. There were close to 2, 800 latrines in the camp of two main types, namely personal latrines constructed by the refugees themselves and collective latrines constructed by relief agencies. The average number of people in the camp is much greater than the standard recommended of 20 people per toilet facility. The study also revealed that the state of the latrines had a great impact on the behaviour of people towards latrines. On a general note, it appears that open air defecation is still a matter of concern in the camp. Whatever the case, there is a need to balance the number of boreholes and construct more latrines in order to meet the standards.
Locally measured variables such as temperature and rainfall have been positively associated with ... more Locally measured variables such as temperature and rainfall have been positively associated with increased cholera incidence in multiple studies. The study examined the effect of rainfall, temperature and relative humidity on cholera incidence in the City of Maroua, located in the Far North of Cameroon. The relative individual contribution of rainfall, temperature and humidity and then their combined contribution on the occurrence of cholera were examined. Using monthly time series of cholera epidemiological data, average monthly rainfall (mm), average monthly air temperature (degree Celsius), and average monthly relative humidity (percent) data from 1996 to 2011.We implemented Generalized Additive Modeling (GAM) procedures to measure the contribution of each weather parameter to the incidence of cholera and identified the most influential parameter on cholera incidence. We found that taken individually, rainfall, temperature and humidity are correlated with cholera incidence but temperature seems more determinant since it has a higher deviance explained (26%). Furthermore, the association between temperature and rainfall in the multivariate model with interaction has the highest deviance explained is 64.4%, the lowest AIC is 1911.963, and the highest R 2 (0.6). These results indicate that statistical time series models in general and the Generalized Additive models in particular should lead to a better understanding of the disease mechanism that can assist in the planning of public health interventions. These results contribute also to the growing debate on climate and cholera.
Revue d'élevage et de médecine vétérinaire des pays tropicaux, 2019
An entomological study was carried out in the Far North region of Cameroon – historically known f... more An entomological study was carried out in the Far North region of Cameroon – historically known focus for animal trypanosomosis and declared tsetse free in the late 1970s – to determine the potential mechanical vectors for trypanosomes and their spatial preference in this region. Thirty-one Nzi traps were installed at 6:30–8:00 a.m. in Goulfey, Madiako canton and Darack karena in Logone and Chari Division, as well as in Guidiguis, Kalfou and Maga-Guirvidig in two other divisions. They were visited after 10–11 hours of exposition. The sampling lasted one day. A total of 20,084 hematophagous flies (865 Stomoxys and 19,219 tabanids) were collected. Stomoxys niger was the only Stomoxyinae species caught, whereas five species of tabanids were collected: Atylotus agrestis , A. albipalpus , A. fuscipes , Tabanus taeniola and T. biguttatus . A. agrestis was by far the most prevalent species (92.7%), followed by T. taeniola (7.1%). The apparent densities of 50.1, 409.4 and 1499.0 tabanids pe...
Revue d’élevage et de médecine vétérinaire des pays tropicaux, 2019
Une étude entomologique a été menée dans la région de l’Extrême-Nord du Cameroun – foyer historiq... more Une étude entomologique a été menée dans la région de l’Extrême-Nord du Cameroun – foyer historiquement connu pour la trypanosomose animale et déclaré exempt de glossines à la fin des années 1970 – afin de déterminer les vecteurs mécaniques potentiels des trypanosomes et leur préférence spatiale dans cette région. Trente et un pièges Nzi ont été installés le matin (6 h 30 – 8 h 00) à Goulfey, Madiako canton, Darack Karena dans le département de Logone et Chari, ainsi qu’à Guidiguis, Kalfou et Maga-Guirvidig dans deux autres départements. Ils ont été inspectés après 10 à 11 heures d’exposition. L’échantillonnage a duré un jour. Au total 20 084 mouches hématophages (865 Stomoxys et 19 219 tabanidés) ont été récoltées. Stomoxys niger a été la seule espèce de Stomoxyinae capturée, alors que cinq espèces de tabanidés ont été relevées : Atylotus agrestis, A. albipalpus, A. fuscipes, Tabanus taeniola et T. biguttatus. A. agrestis était de loin l’espèce la plus répandue (92,7 %), suivie de ...
Revue d'élevage et de médecine vétérinaire des pays tropicaux, 2019
An entomological study was carried out in the Far North region of Cameroon – historically known f... more An entomological study was carried out in the Far North region of Cameroon – historically known focus for animal trypanosomosis and declared tsetse free in the late 1970s – to determine the potential mechanical vectors for trypanosomes and their spatial preference in this region. Thirty-one Nzi traps were installed at 6:30–8:00 a.m. in Goulfey, Madiako canton and Darack karena in Logone and Chari Division, as well as in Guidiguis, Kalfou and Maga-Guirvidig in two other divisions. They were visited after 10–11 hours of exposition. The sampling lasted one day. A total of 20,084 hematophagous flies (865 Stomoxys and 19,219 tabanids) were collected. Stomoxys niger was the only Stomoxyinae species caught, whereas five species of tabanids were collected: Atylotus agrestis , A. albipalpus , A. fuscipes , Tabanus taeniola and T. biguttatus . A. agrestis was by far the most prevalent species (92.7%), followed by T. taeniola (7.1%). The apparent densities of 50.1, 409.4 and 1499.0 tabanids pe...
Journal of Vector Borne Diseases, 2017
Background & objectives: The Far-North region of Cameroon has been considered free of tsetse ... more Background & objectives: The Far-North region of Cameroon has been considered free of tsetse and trypanosomiasis for the past three decades. But recent reports by pastoralists indicate its reappearance in the region. This study was aimed to confirm the existence of cattle trypanosomiasis and determine its prevalence, and to establish pastoralists knowledge and practice (KP) of the disease in Ndiyam Shinwa pastoral zone of Cameroon. Methods: A total of 118 herds were surveyed for a descriptive, cross-sectional study in Ndiyam Shinwa pastoral zone from May to November 2014. Out of these, 110 herds were visited in the beginning of the rainy season, 22 of the 110 herds (suspect cattle) were revisited along with the remaining eight herds in the end of the season. The blood samples of 635 suspect cattle and 135 nonsuspect cattle were collected. Samples were subjected to two diagnostic tests: Buffy coat test (BCT) and packed cell volume (PCV) determination. A survey on pastoralist’s (n = 118) KP about trypanosomiasis was also undertaken. Results: Parasitological analyses revealed six infections by Trypanosoma vivax: Four in suspect cattle against two in nonsuspect cattle, corresponding respectively to apparent prevalence of 0.63 and 1.46% and true prevalence of (0.79–3.15%) and (1.82–7.30%). The proportion of cattle found infected in the PCV as well as BCT tests was 33.26% for suspect cattle. More than 75% of followed-up suspects showed persisting symptoms nearly three months after initial examination. The most common diagnostic signs for pastoralists were ruffled hair, lacrimation, anorexia and emaciation. Interpretation & conclusion: Cattle trypanosomiasis has reappeared in the Far-North region and seems to be in the inter-epizootic phase. Pastoralists have a good knowledge of the disease, but their perception of its importance seems to be influenced by the persistence of symptoms attributed to this disease in suspect cattle.
Geographia Technica, 2019
Locally measured variables such as temperature and rainfall have been positively associated with ... more Locally measured variables such as temperature and rainfall have been positively associated with increased cholera incidence in multiple studies. The study examined the effect of rainfall, temperature and relative humidity on cholera incidence in the City of Maroua, located in the Far North of Cameroon. The relative individual contribution of rainfall, temperature and humidity and then their combined contribution on the occurrence of cholera were examined. Using monthly time series of cholera epidemiological data, average monthly rainfall (mm), average monthly air temperature (degree Celsius), and average monthly relative humidity (percent) data from 1996 to 2011.We implemented Generalized Additive Modeling (GAM) procedures to measure the contribution of each weather parameter to the incidence of cholera and identified the most influential parameter on cholera incidence. We found that taken individually, rainfall, temperature and humidity are correlated with cholera incidence but temperature seems more determinant since it has a higher deviance explained (26%). Furthermore, the association between temperature and rainfall in the multivariate model with interaction has the highest deviance explained is 64.4%, the lowest AIC is 1911.963, and the highest R 2 (0.6). These results indicate that statistical time series models in general and the Generalized Additive models in particular should lead to a better understanding of the disease mechanism that can assist in the planning of public health interventions. These results contribute also to the growing debate on climate and cholera.
Cholera is an acute infection caused by ingestion of food or water contaminated with the bacteriu... more Cholera is an acute infection caused by ingestion of food or water contaminated with the bacterium Vibrio cholerae. We used cholera epidemics data from 1996 to 2011 to describe the geographical pattern of cholera incidence in the Far North. The incidence rate of cholera per 10 000 persons and the cumulative incidence rate of the various epidemics were computed for each of the health districts. The data were entered into a GIS for visualisation and mapping. This study shows that cholera outbreak followed a specific spatial pattern and that GIS mapping can be useful to health services. Résumé: Le choléra est une infection aiguë causée par l'ingestion d'aliments ou d'eau contaminés par la bactérie Vibrio cholerae. Nous avons utilisé les données des épidémies de choléra de 1996 à 2011 pour décrire la répartition géographique de l'incidence du choléra dans l'Extrême Nord. Le taux d'incidence du choléra pour 10 000 personnes et le taux d'incidence cumulé des di...
Revue d’élevage et de médecine vétérinaire des pays tropicaux, 2019
Une étude entomologique a été menée dans la région de l’Extrême-Nord du Cameroun – foyer historiq... more Une étude entomologique a été menée dans la région de l’Extrême-Nord du Cameroun – foyer historiquement connu pour la trypanosomose animale et déclaré exempt de glossines à la fin des années 1970 – afin de déterminer les vecteurs mécaniques potentiels des trypanosomes et leur préférence spatiale dans cette région. Trente et un pièges Nzi ont été installés le matin (6 h 30 – 8 h 00) à Goulfey, Madiako canton, Darack Karena dans le département de Logone et Chari, ainsi qu’à Guidiguis, Kalfou et Maga-Guirvidig dans deux autres départements. Ils ont été inspectés après 10 à 11 heures d’exposition. L’échantillonnage a duré un jour. Au total 20 084 mouches hématophages (865 Stomoxys et 19 219 tabanidés) ont été récoltées. Stomoxys niger a été la seule espèce de Stomoxyinae capturée, alors que cinq espèces de tabanidés ont été relevées : Atylotus agrestis, A. albipalpus, A. fuscipes, Tabanus taeniola et T. biguttatus. A. agrestis était de loin l’espèce la plus répandue (92,7 %), suivie de ...
Résumé Les migrations sont au cur des questions de développement en Afrique centrale à cause d... more Résumé Les migrations sont au cur des questions de développement en Afrique centrale à cause de l'augmentation de la population et de la situation économique délétère. C'est dans cette perspective que les Etats de la sous-région ont tenté d'encadrer les migrations. ...
Journal of Vector Borne Diseases, 2017
Background & objectives: The Far-North region of Cameroon has been considered free of tsetse ... more Background & objectives: The Far-North region of Cameroon has been considered free of tsetse and trypanosomiasis for the past three decades. But recent reports by pastoralists indicate its reappearance in the region. This study was aimed to confirm the existence of cattle trypanosomiasis and determine its prevalence, and to establish pastoralists knowledge and practice (KP) of the disease in Ndiyam Shinwa pastoral zone of Cameroon. Methods: A total of 118 herds were surveyed for a descriptive, cross-sectional study in Ndiyam Shinwa pastoral zone from May to November 2014. Out of these, 110 herds were visited in the beginning of the rainy season, 22 of the 110 herds (suspect cattle) were revisited along with the remaining eight herds in the end of the season. The blood samples of 635 suspect cattle and 135 nonsuspect cattle were collected. Samples were subjected to two diagnostic tests: Buffy coat test (BCT) and packed cell volume (PCV) determination. A survey on pastoralist’s (n = 118) KP about trypanosomiasis was also undertaken. Results: Parasitological analyses revealed six infections by Trypanosoma vivax: Four in suspect cattle against two in nonsuspect cattle, corresponding respectively to apparent prevalence of 0.63 and 1.46% and true prevalence of (0.79–3.15%) and (1.82–7.30%). The proportion of cattle found infected in the PCV as well as BCT tests was 33.26% for suspect cattle. More than 75% of followed-up suspects showed persisting symptoms nearly three months after initial examination. The most common diagnostic signs for pastoralists were ruffled hair, lacrimation, anorexia and emaciation. Interpretation & conclusion: Cattle trypanosomiasis has reappeared in the Far-North region and seems to be in the inter-epizootic phase. Pastoralists have a good knowledge of the disease, but their perception of its importance seems to be influenced by the persistence of symptoms attributed to this disease in suspect cattle.
The Pan African medical journal, 2017
In recent years, the Far North Region of Cameroon has experienced serious and recurrent cholera o... more In recent years, the Far North Region of Cameroon has experienced serious and recurrent cholera outbreaks. Yet, understanding of cultural influences on outbreaks and spread remain poorly understood. This qualitative study explored cultural influences on cholera exposure in this region. Interviews and group discussions were conducted in two phases. Phase I involved key informants and phase II included focus group and household discussions. Thematic techniques including word repetition, key-indigenous-terms, and key-words-in-context were used for qualitative data analysis. Key informants attributed cholera etiology to dirt and spread through water () and food (group eating or ) while group discussions attributed it to a reprimand from and transmission through the air. Participants suggested that funerals, weddings, open defecation, and mountaintop burial might influence cholera exposure and facilitate its spread. Hospital avoidance and non-adherence with cholera treatment regimens wer...
International journal of environmental research and public health, Apr 20, 2017
The Far North region in Cameroon has been more heavily impacted by cholera than any other region ... more The Far North region in Cameroon has been more heavily impacted by cholera than any other region over the past decade, but very little has been done to study the drivers of waterborne diseases in the region. We investigated the relationship between water, sanitation, and hygiene (WASH) parameters, microbial and antibiotic resistance (AR) contamination levels in drinking water, and health outcomes using health survey and molecular analysis during June and July of 2014 in two settlement types (agro-pastoralist villages and transhumant pastoralist camps). Quantitative polymerase chain reaction was used to determine fecal contamination sources, enteric pathogens, and antibiotic resistance genes. Ruminant-associated fecal contamination was widespread in both settlement types (81.2%), with human-associated contamination detected in 21.7% of the samples. Salmonella spp. (59.4%) and Shiga toxin-producing E. coli (stx1 44.9% and stx2 31.9%) were detected across all samples. Tetracycline resi...
PLoS neglected tropical diseases, 2016
Recurrent cholera outbreaks have been reported in Cameroon since 1971. However, case fatality rat... more Recurrent cholera outbreaks have been reported in Cameroon since 1971. However, case fatality ratios remain high, and we do not have an optimal understanding of the epidemiology of the disease, due in part to the diversity of Cameroon's climate subzones and a lack of comprehensive data at the health district level. A unique health district level dataset of reported cholera case numbers and related deaths from 2000-2012, obtained from the Ministry of Public Health of Cameroon and World Health Organization (WHO) country office, served as the basis for the analysis. During this time period, 43,474 cholera cases were reported: 1748 were fatal (mean annual case fatality ratio of 7.9%), with an attack rate of 17.9 reported cases per 100,000 inhabitants per year. Outbreaks occurred in three waves during the 13-year time period, with the highest case fatality ratios at the beginning of each wave. Seasonal patterns of illness differed strikingly between climate subzones (Sudano-Sahelian,...
From Data to Knowledge to Healthcare Improvement, 2016
Journal of Water and Health, 2016
This study examined the spatial variation of potential gastrointestinal pathogens within drinking... more This study examined the spatial variation of potential gastrointestinal pathogens within drinking water sources and home storage containers in four neighborhoods in Maroua, Cameroon. Samples were collected from source (n= 28) and home containers (n= 60) in each study neighborhood. Pathogen contamination was assessed using quantitative polymerase chain reaction, targeting Campylobacter spp., Shiga toxin producing Escherichia coli (virulence genes, stx1 and stx2), and Salmonella spp. Microbial source tracking (MST) targeted three different host-specific markers: HF183 (human), Rum2Bac (ruminant) and GFD (poultry) to identify contamination sources. Staphylococcus aureus and the tetracycline-resistance gene (tetQ) were assessed to measure human hand contact and presence of antibiotic-resistant bacteria. Pathogen/MST levels were compared statistically and spatially, and neighborhood variation was compared with previously collected demographic information. All the test fecal markers and p...
Edition Cheihk Anta Diop, 2022
L’ouvrage traite d’une problématique réelle qui mine la vie quotidienne dans la ville de Maroua. ... more L’ouvrage traite d’une problématique réelle qui mine la vie quotidienne dans la ville de Maroua. Il s’agit d’un travail de recherche appliquée dans lequel les auteurs, partant des bases théoriques en la matière, font un diagnostic sans complaisance et proposent des solutions adaptées au contexte local pour la réduction des risques. L’ouvrage organisé en quatre chapitres, présente un état des lieux des événements catastrophiques auxquels cette ville est confrontée, analyse leur mode de gestion et les facteurs de vulnérabilité, puis propose des stratégies préventives adaptées inspirées du Cadre de résilience urbaine et des prescriptions de la Stratégie Internationale de Réduction de Risque. Les thèmes abordées (risques, vulnérabilité, résilience) relèvent non seulement du contexte international en plein essor impulsé par les Nations Unies, mais aussi constitue un support de formation complémentaire en Sciences Environnementales et en Géographie. L’ouvrage s’adresse aussi bien aux chercheurs, étudiants, praticiens, qu’aux acteurs de la gouvernance urbaine.
Edition Cheik Anta Diop, 2019
Le Cameroun, comme les autres pays, n’est pas épargné des catastrophes naturelles. Malgré le fait... more Le Cameroun, comme les autres pays, n’est pas épargné des catastrophes naturelles. Malgré le fait que la prévention soit l’une des trois mesures de protection civile inscrites dans la loi, il y’a lieu de constater la faiblesse des actions préventives face aux catastrophes. Dans cet ouvrage qui comporte cinq chapitres nous abordons dans un premier temps les concepts de base et le cadre théorique des catastrophes. Les principaux risques de catastrophes naturels ainsi que les principales catastrophes qui ont frappé le Cameroun ces dernières années sont ensuite revisitées avant d’examiner le cadre national de la gouvernance des catastrophes. Une approche de mise en œuvre de l’alerte précoce axée sur la population est enfin proposée, illustrée par un exemple pilote mis en œuvre dans une municipalité de la Région de l’Extrême Nord. Un certain nombre de textes régissant le cadre de la protection civile au Cameroun vient enrichir l’ouvrage en annexe.