SARS-CoV-2 seroprevalence among Beninese pregnant women in the third year of the pandemic.

BACKGROUND: Pregnant women are a vulnerable population to COVID-19 given an increased susceptibility to severe SARS-CoV-2 infection and pregnancy complications. However, few SARS-CoV-2 serological surveys have been performed among this population to assess the extent of the infection in sub-Saharan countries. The objectives of this study were to determine SARS-CoV-2 seroprevalence among Beninese pregnant women, to identify spatial seropositivity clusters and to analyse factors associated with the infection. METHODS: A cross-sectional study including women in their third trimester of pregnancy attending the antenatal care (ANC) clinics at Allada (south Benin) and Natitingou (north Benin) was conducted. Rapid diagnostic tests (RDT) for detection of IgG/IgM against the SARS-CoV-2 spike protein were performed using capillary blood. Seroprevalence of SARS-CoV-2 antibodies and associations between SARS-CoV-2 serostatus and maternal characteristics were analyzed by multivariate logistic regression. Spatial analyses were performed using the spatial scan statistics to identify spatial clusters of SARS-CoV-2 infection. RESULTS: A total of 861 pregnant women were enrolled between May 4 and June 29, 2022. 58/861 (6.7%) participants reported having received COVID-19 vaccine. None of the participants had been diagnosed with COVID-19 during their pregnancy. SARS-CoV-2 antibodies were detected in 607/802 (75.7%; 95% CI 72.56%-78.62%) of unvaccinated participants. Several urban and rural spatial clusters of SARS-CoV-2 cases were identified in Allada and one urban spatial cluster was identified in Natitingou. Unvaccinated participants from Allada with at least one previous morbidity were at a three-times higher risk of presenting SARS-CoV-2 antibodies (OR = 2.89; 95%CI 1.19%-7.00%). CONCLUSION: Three out of four pregnant women had SARS-CoV-2 antibodies, suggesting a high virus circulation among pregnant women in Benin, while COVID-19 vaccination coverage was low. Pregnant women with comorbidities may be at increased risk of SARS-CoV-2 infection. This population should be prioritized for COVID-19 diagnosis and vaccination in order to prevent its deleterious effects. TRIAL REGISTRATION: NCT06170320 (retrospectively registered on December 21, 2023).

Effects of a free health insurance programme for the poor on health service utilisation and financial protection in Senegal.

INTRODUCTION: Implemented in 2013 in Senegal, the Programme National de Bourses de Sécurité Familiale (PNBSF) is a national cash transfer programme for poor households. Besides reducing household poverty and encouraging children's school attendance, an objective of the PNBSF is to expand health coverage by guaranteeing free enrolment in community-based health insurance (CBHI) schemes. In this paper, we provide the first assessment of the PNBSF free health insurance programme on health service utilisation and health-related financial protection. METHODS: We collected household-level and individual-level cross-sectional data on health insurance in 2019-2020 within the Niakhar Population Observatory in rural Senegal. We conducted a series of descriptive analyses to fully describe the application of the PNBSF programme in terms of health coverage. We then used multivariate logistic and Poisson regression models within an inverse probability weighting framework to estimate the effect of being registered in a CBHI through the PNBSF-as compared with having no health insurance or having voluntarily enrolled in a CBHI scheme-on a series of outcomes. RESULTS: With the exception of health facility deliveries, which were favoured by free health insurance, the PNBSF did not reduce the unmet need for healthcare or the health-related financial risk. It did not increase individuals' health service utilisation in case of health problems, did not increase the number of antenatal care visits and did not protect households against the risk of forgoing medical care and of catastrophic health expenditure. CONCLUSION: We found limited effects of the PNBSF free health insurance on health service utilisation and health-related financial protection, although these failures were not necessarily due to the provision of free health insurance per se. Our results point to both implementation failures and limited programme outcomes. Greater commitment from the state is needed, particularly through strategies to reduce barriers to accessing covered healthcare.

Between traditional remedies and pharmaceutical drugs: prevention and treatment of "Palu" in households in Benin, West Africa.

BACKGROUND: In Benin, malaria clinical cases, including the larger popular entity called "Palu" are evoked when people get fever. "Palu" is often self-diagnosed and self-medicated at home. This study aimed to describe the use of herbal medicine, and/or pharmaceutical medicines for prevention and treatment of malaria at home and the factors associated with this usage. METHODS: A cross-sectional survey was conducted in Benin in an urban and in a rural area in 2016. Around 600 households in each place were selected by using a random sampling of houses GPS coordinates of the families. The association between socio demographic characteristics and the use of herbal medicine was tested by using logistic regression models. RESULTS: In Cotonou (urban), 43.64% of households reported using herbal or pharmaceutical medicine to prevent "Palu", while they were 53.1% in Lobogo (rural). To treat "Palu" in Cotonou, 5.34% of households reported using herbal medicine exclusively, 33.70% pharmaceutical medicine exclusively and 60.96% reported using both. In Lobogo, 4% reported using herbal medicine exclusively, 6.78% pharmaceutical medicine exclusively and 89.22% reported using both. In Cotonou, the factors "age of respondent", "participation to a traditional form of savings" and "low socioeconomic level of the household" were associated with the use of herbal medicine. CONCLUSIONS: This study shows the strong use of herbal medicine to prevent "Palu" or even treat it, and in this case it is mostly associated with the use of pharmaceutical medicine. It also highlights the fact that malaria control and care seeking behaviour with herbal medicine remain closely linked to household low-income status but also to cultural behaviour. The interest of this study is mostly educational, with regards to community practices concerning "Palu", and to the design of adapted behaviour change communication strategies. Finally, there is a need to take into account the traditional habits of populations in malaria control and define a rational and risk-free use of herbal medicine as WHO-recommended.

Molecular characterization and mapping of glucose-6-phosphate dehydrogenase (G6PD) mutations in the Greater Mekong Subregion.

BACKGROUND: Plasmodium vivax malaria elimination can only be achieved by the deployment of 8-aminoquinolines (primaquine and tafenoquine) in combination with ACT to kill both blood and liver-stage parasites. However, primaquine and the other 8-aminoquinolines cause dose-dependent haemolysis in subjects with G6PD deficiency, an X-linked disorder of red blood cells that is very common in populations living in tropical and subtropical areas. In order to inform safer use of 8-aminoquinolines in the Greater Mekong Subregion, a multi-centre study was carried out to assess the prevalence of G6PD deficiency and to identify the main G6PD variants in samples collected in Cambodia, Lao PDR, Myanmar, Thailand and Vietnam. METHODS: Blood samples were collected in the five countries during National Malaria Surveys or during Population Surveys. During Population Surveys samples were characterized for G6PD phenotype using the Fluorescent Spot Test. Samples were then genotyped for a panel of G6PD mutations. RESULTS: G6PD deficiency was found to be common in the region with an overall mean prevalence of deficient or mutated hemizygous males of 14.0%, ranging from a mean 7.3% in Thailand, 8.1% in Lao PDR, 8.9% in Vietnam, 15.8% in Myanmar and 18.8% in Cambodia. Mahidol and Viangchan mutations were the most common and widespread variants found among the nine investigated. CONCLUSIONS: Owing to the high prevalence of G6PD deficiency in the Greater Mekong Subregion, strategies for vivax malaria elimination should include point-of-care G6PD testing (both qualitative and quantitative) to allow safe and wide treatment with 8-aminoquinolines.

Home treatment and use of informal market of pharmaceutical drugs for the management of paediatric malaria in Cotonou, Benin.

BACKGROUND: Malaria is the main cause of hospital admissions in Benin and a leading cause of death in childhood. Beside consultations, various studies have underlined the management of the disease through home treatment. The medicines used can be purchased in informal market of pharmaceutical drugs (IMPD) without prescription or any involvement of healthcare professional. Pharmaceutical drugs are sold by informal private vendors, who operate at any time in the immediate environment of the patients. The present study was conducted in Cotonou to study the health-seeking behaviour of caregivers to treat malaria in children under 12 years old. Factors associated with malaria home treatment and drugs purchase in IMPD were studied. METHODS: A cross-sectional study was carried out among 340 children's caregivers who were interviewed about their socio-demographic characteristics and their care-seeking behaviour during the most recent episode of malaria in their children under 12. Medicines used and purchase place were also collected. Multivariate logistic regression model was used to determine factors associated with malaria home treatment and drug purchase in IMPD. RESULTS: Beyond all the 340 caregivers, 116 (34%) consulted healthcare professional, 224 (66%) home treat the children, among whom 207 (61%) gave pharmaceutical drugs and 17 (5%) gave traditional remedies to children. Malaria home treatment was associated with family size, health insurance (OR = 0.396, 95% CI 0.169-0.928), and wealth quintiles where home treatment was less used by the richest (OR = 0.199, 95% CI 0.0676-0.522) compared to those in the poorest quintile. The caregivers age group 30-39 years was associated to the use of IMPD (OR = 0.383, 95% CI 0.152-0.964), the most economically wealthy people were less likely to use IMPD (wealth quintile richest: OR = 0.239, 95% CI 0.064-0.887; wealth quintile fourth OR = 0.271, 95% CI 0.100-0.735) compared to those in the poorest quintile. All caregivers who benefited from health insurance did not use IMPD. CONCLUSION: This study highlights the link between worse economic conditions and accessibility to medical care as one of the main factors of malaria home treatment and drug purchase in IMPD, even if those two phenomena need to be understood apart.

Prevalence of malaria in pregnancy in southern Laos: a cross-sectional survey.

BACKGROUND: There are no data on the burden of malaria in pregnancy (MiP) in Laos, where malaria still remains prevalent in the south. METHODS: Two cross-sectional surveys were conducted in 2014 to assess the prevalence of MiP in Vapi District, Salavan Province, southern Laos: the first consisted of screening 204 pregnant women during pregnancies [mean (95 % CI) gestational age: 23 (22-25) weeks] living in 30 randomly selected villages in Vapi District; the second was conducted among 331 pregnant women, who delivered during the study period in Vapi and Toumlane District Hospitals and in Salavan Provincial Hospital. Peripheral and placental malaria was detected using rapid diagnostic tests (RDT), thick blood smears (TBS) and real-time quantitative polymerase chain reactions (RT-qPCR). Factors associated with low birth weight (LBW) and maternal anaemia were assessed. RESULTS: In the villages, 12/204 women (5.9 %; 95 % CI 3.1-10.0) were infected with malaria as determined by RT-qPCR: 11 were Plasmodium vivax infections and 1 was mixed Plasmodium vivax/Plasmodium falciparum infection, among which 9 were sub-microscopic (as not detected by TBS). History of malaria during current pregnancy tended to be associated with a higher risk of MiP (aIRR 3.05; 95 % CI 0.94-9.88). At delivery, two Plasmodium falciparum sub-microscopic infections (one peripheral and one placental) were detected (4.5 %; 0.6-15.5) in Vapi District. In both surveys, all infected women stated they had slept under a bed net the night before the survey, and 86 % went to the forest for food-finding 1 week before the survey in median. The majority of infections (94 %) were asymptomatic and half of them were associated with anaemia. Overall, 24 % of women had LBW newborns. Factors associated with a higher risk of LBW were tobacco use (aIRR 2.43; 95 % CI 1.64-3.60) and pre-term delivery (aIRR 3.17; 95 % CI 2.19-4.57). Factors associated with a higher risk of maternal anaemia were no iron supplementation during pregnancy, Lao Theung ethnicity and place of living. CONCLUSIONS: The prevalence of MiP in this population was noticeable. Most infections were asymptomatic and sub-microscopic vivax malaria, which raises the question of reliability of recommended national strategies for the screening and prevention of MiP in Laos.

Use of health care among febrile children from urban poor households in Senegal: does the neighbourhood have an impact?

Urban malaria is considered a major public health problem in Africa. The malaria vector is well adapted in urban settings and autochthonous malaria has increased. Antimalarial treatments prescribed presumptively or after rapid diagnostic tests are also highly used in urban settings. Furthermore, health care strategies for urban malaria must comply with heterogeneous neighbourhood ecosystems where health-related risks and opportunities are spatially varied. This article aims to assess the capacity of the urban living environment to mitigate or increase individual or household vulnerabilities that influence the use of health services. The data are drawn from a survey on urban malaria conducted between 2008 and 2009. The study sample was selected using a two-stage randomized sampling. The questionnaire survey covered 2952 households that reported a case of fever episode in children below 10 years during the month before the survey.Self-medication is a widespread practice for children, particularly among the poorest households in Dakar. For rich households, self-medication for children is more a transitional practice enabling families to avoid opportunity costs related to visits to health facilities. For the poorest, it is a forced choice and often the only treatment option. However, the poor that live in well-equipped neighbourhoods inhabited by wealthy residents tend to behave as their rich neighbours. They grasp the opportunities provided by the area and adjust their behaviours accordingly. Though health care for children is strongly influenced by household socio-economic characteristics, neighbourhood resources (facilities and social networks) will promote health care among the poorest and reduce access inequalities. Without being a key factor, the neighbourhood of residence-when it provides resources-may be of some help to overcome the financial hurdle. Findings suggest that the neighbourhood (local setting) is a relevant scale for health programmes in African cities.

Coinfection with Plasmodium falciparum and Schistosoma haematobium: additional evidence of the protective effect of Schistosomiasis on malaria in Senegalese children.

Parasitic infections are associated with high morbidity and mortality in developing countries. Several studies focused on the influence of helminth infections on malaria but the nature of the biological interaction is under debate. Our objective was to undertake a study to explore the influence of the measure of excreted egg load caused by Schistosoma haematobium on Plasmodium falciparum parasite densities. Ten measures of malaria parasite density and two measures of schistosomiasis egg urinary excretion over a 2-year follow-up period on 178 Senegalese children were considered. A linear mixed-effect model was developed to take data dependence into account. This work showed that children with a light S. haematobium infection (1-9 eggs/mL of urine) presented lower P. falciparum parasite densities than children not infected by S. haematobium (P < 0.04). Possible changes caused by parasite coinfections should be considered in the anti-helminth treatment of children and in malaria vaccination development.

Perceived malaria in the population of an urban setting: a skipped reality in Dakar, Senegal.

BACKGROUND: Urban malaria remains a public health problem. Dakar is located in a low endemic area. However, anti-malarial drugs consumption is reported to be high despite the decline of malaria announced by health authorities. The objective of the present study was to assess the burden of reported malaria attacks (RMAs) in 2008 and to describe care-seeking behaviours in the population of Dakar, Senegal. METHODS: In this cross-sectional study, 2,952 households selected from 50 sites were visited. In each household, a women and a child between two and 10 years old were interviewed about a malaria episode that occurred in 2008. The following information was recorded: age, education level, sex (for children), type of care seeking, method of diagnosis, use of anti-malarial treatment, place of medication purchase, bed net use, malaria-related deaths in the family, and perceptions of the frequency of mosquito bites. After a description of the variables in each subsample, a Pearson's chi-square test was used to compare proportions, and logistic regression was performed to identify the association between RMAs and other covariates. RESULTS: Among women, 31.8% reported a malaria attack in 2008; among children, the rate of malaria attacks reported by mothers or caretakers was 39.0%. With regard to care-seeking, 79.5% of women and 81.5% of children with a RMA had visited health facilities (HFs). Younger women and children under five years old were more likely to visit a HF (P<0.001). Presumptive diagnosis was the primary method that was used to identify malaria in HFs. For those who had visited a HF, the rate of anti-malarial treatment was 77% in women and 60% in children. Finally, 43.6% of women and 42.0% of children declared the use of bed nets. In a multivariate analysis, the malaria-related death of a relative and perceptions of mosquito bites were significantly associated with RMAs in women. In children, age was associated with RMAs. CONCLUSION: The frequent perceptions of the occurrence of malaria in the population were confirmed at the HF by the high presumptive diagnosis of health professionals. Despite the decline of malaria that has been announced by health authorities, the population will continue to complain of malaria and seek care directly at private pharmacies. This situation may sustain the circulation of anti-malarial drugs and increase the risk of an emergence of anti-malarial resistance.

IgG responses to the gSG6-P1 salivary peptide for evaluating human exposure to Anopheles bites in urban areas of Dakar region, Sénégal.

BACKGROUND: Urban malaria can be a serious public health problem in Africa. Human-landing catches of mosquitoes, a standard entomological method to assess human exposure to malaria vector bites, can lack sensitivity in areas where exposure is low. A simple and highly sensitive tool could be a complementary indicator for evaluating malaria exposure in such epidemiological contexts. The human antibody response to the specific Anopheles gSG6-P1 salivary peptide have been described as an adequate tool biomarker for a reliable assessment of human exposure level to Anopheles bites. The aim of this study was to use this biomarker to evaluate the human exposure to Anopheles mosquito bites in urban settings of Dakar (Senegal), one of the largest cities in West Africa, where Anopheles biting rates and malaria transmission are supposed to be low. METHODS: One cross-sectional study concerning 1,010 (505 households) children (n = 505) and adults (n = 505) living in 16 districts of downtown Dakar and its suburbs was performed from October to December 2008. The IgG responses to gSG6-P1 peptide have been assessed and compared to entomological data obtained in or near the same district. RESULTS: Considerable individual variations in anti-gSG6-P1 IgG levels were observed between and within districts. In spite of this individual heterogeneity, the median level of specific IgG and the percentage of immune responders differed significantly between districts. A positive and significant association was observed between the exposure levels to Anopheles gambiae bites, estimated by classical entomological methods, and the median IgG levels or the percentage of immune responders measuring the contact between human populations and Anopheles mosquitoes. Interestingly, immunological parameters seemed to better discriminate the exposure level to Anopheles bites between different exposure groups of districts. CONCLUSIONS: Specific human IgG responses to gSG6-P1 peptide biomarker represent, at the population and individual levels, a credible new alternative tool to assess accurately the heterogeneity of exposure level to Anopheles bites and malaria risk in low urban transmission areas. The development of such biomarker tool would be particularly relevant for mapping and monitoring malaria risk and for measuring the efficiency of vector control strategies in these specific settings.

Asymptomatic carriage of plasmodium in urban Dakar: the risk of malaria should not be underestimated.

INTRODUCTION: The objective of this study was to measure the rate of asymptomatic carriage of plasmodium in the Dakar region two years after the implementation of new strategies in clinical malaria management. METHODOLOGY: Between October and December 2008, 2952 households selected in 50 sites of Dakar area, were visited for interviews and blood sampling. Giemsa-stained thick blood smears (TBS) were performed for microscopy in asymptomatic adult women and children aged 2 to 10 years. To ensure the quality of the microscopy, we performed a polymerase chain reaction (PCR) with real time qPCR in all positive TBS by microscopy and in a sample of negative TBS and filter paper blood spots. RESULTS: The analysis has concerned 2427 women and 2231 children. The mean age of the women was 35.6 years. The mean age of the children was 5.4 years. The parasite prevalence was 2.01% (49/2427) in women and 2.15% (48/2231) in children. Parasite prevalence varied from one study site to another, ranging from 0 to 7.41%. In multivariate analysis, reporting a malaria episode in 2008 was associated with plasmodium carriage (OR = 2.57, P = 0.002) in women; in children, a malaria episode (OR = 6.19, P<0.001) and a travel out of Dakar during last 3 months (OR = 2.27, P = 0.023) were associated with plasmodium carriage. Among the positive TBS, 95.8% (93/97) were positive by plasmodium PCR. Among the negative TBS, 13.9% (41/293) were positive by PCR. In blood spots, 15.2% (76/500) were positive by PCR. We estimated at 16.5% the parasite prevalence if PCR were performed in 4658 TBS. CONCLUSION: Parasite prevalence in Dakar area seemed to be higher than the rate found by microscopy. PCR may be the best tool for measuring plasmodium prevalence in the context of low transmission. Environmental conditions play a major role in the heterogeneity of parasite prevalence within sites.

Management of uncomplicated malaria in children under 13 years of age at a district hospital in Senegal: from official guidelines to usual practices.

BACKGROUND: To be effective, national malaria guidelines must be properly followed. This study evaluated nurses' practices in the management of uncomplicated malaria cases at a District Hospital. Its objective was to identify the reasons for discrepancies between official guidelines and usual practices. METHODS: This study took place at Oussouye hospital, south-western Senegal. Blood smears were available for biological diagnosis in patients aged more than five years while the Integrated Management of Childhood Illness recommended treating fevers presumptively in children under five. First line anti-malarial was Amodiaquine plus sulphadoxine-pyrimethamine (AQ+SP) bi-therapy. Hospital records of children under 13 years of age seen between 2004 and 2005 were reviewed. RESULTS: Among children treated with anti-malarials, 74% (2, 063/2, 789) received AQ+SP. However, only 22% (406/1, 879) of febrile children and 19% (429/2, 198) of children diagnosed with malaria got a blood smear. Moreover, an anti-malarial was prescribed for 80% (377/474) of children with a negative blood smear. CONCLUSIONS: The transition from chloroquine to AQ+SP was well followed. Nonetheless, blood smear use was very low and many over-prescriptions were reported. Reasons for discrepancies between guidelines and practices can be classified in three main categories: ambiguous guidelines, health system's dysfunctions and nurses' own considerations. Aside from the strengthening of the public health system, in order to guarantee practices complying with guidelines, training content should be more adapted to nurses' own considerations.

Where do pharmaceuticals on the market originate? An analysis of the informal drug supply in Cotonou, Benin.

This anthropological study, conducted in Cotonou, Benin between 2005 and 2007, investigates the informal pharmaceuticals market. It was carried out through a long-term participant observation of informal vendors and semi-directive and unstructured interviews. A classification of products sold in the informal market was developed. The fact that a high percentage of them come from Anglophone countries near Benin (Nigeria and Ghana) led to a comparison of the sources of pharmaceutical supply in these three countries as well as their current legislation regarding pharmaceutical distribution. Our study results highlight a new understanding of the phenomenon of the informal market. Nigeria and Ghana rely on a liberal pharmaceutical distribution system with little intervention from public authorities. Conversely, the government maintains considerable influence over pharmaceutical distribution in Benin. Hence, the differences between these three countries in terms of variety of supply sources and flexibility of access to drugs are understood through an investigation of Benin's informal market. Therefore, it appears that beyond issues concerning the quality of the pharmaceuticals, this phenomenon illustrates a kind of liberalization of pharmaceutical distribution and the ensuing public health issues.

Self-reported data: a major tool to assess compliance with anti-malarial combination therapy among children in Senegal.

BACKGROUND: Although there are many methods available for measuring compliance, there is no formal gold standard. Different techniques used to measure compliance were compared among children treated by the anti-malarial amodiaquine/sulphadoxine-pyrimethamine (AQ/SP) combination therapy, in use in Senegal between 2004 and 2006. METHODS: The study was carried out in 2004, in five health centres located in the Thies region (Senegal). Children who had AQ/SP prescribed for three and one day respectively at the health centre were recruited. The day following the theoretical last intake of AQ, venous blood, and urine samples were collected for anti-malarial drugs dosage. Caregivers and children above five years were interviewed concerning children's drug intake. RESULTS: Among the children, 64.7% adhered to 80% of the prescribed dose and only 37.7% were strict full adherent to the prescription. There was 72.7% agreement between self-reported data and blood drug dosage for amodiaquine treatment. Concerning SP, results found that blood dosages were 91.4% concordant with urine tests and 90% with self-reported data based on questionnaires. CONCLUSION: Self-reported data could provide useful quantitative information on drug intake and administration. Under strict methodological conditions this method, easy to implement, can be used to describe patients' behaviors and their use of new anti-malarial treatment. Self-reported data is a major tool for assessing compliance in resource poor countries. Blood and urine drug dosages provide qualitative results that confirm any drug intake. Urine assays for SP could be useful to obtain public health data, for example on chemoprophylaxis among pregnant women.

Factors related to compliance to anti-malarial drug combination: example of amodiaquine/sulphadoxine-pyrimethamine among children in rural Senegal.

BACKGROUND: The introduction of new anti-malarial treatment that is effective, but more expensive, raises questions about whether the high level of effectiveness observed in clinical trials can be found in a context of family use. The objective of this study was to determine the factors related to adherence, when using the amodiaquine/sulphadoxine-pyrimethamine (AQ/SP) association, a transitory strategy before ACT implementation in Senegal. METHODS: The study was conducted in five rural dispensaries. Children, between two and 10 years of age, who presented mild malaria were recruited at the time of the consultation and were prescribed AQ/SP. The child's primary caretaker was questioned at home on D3 about treatment compliance and factors that could have influenced his or her adherence to treatment. A logistic regression model was used for the analyses. RESULTS: The study sample included 289 children. The adherence rate was 64.7%. Two risks factors for non-adherence were identified: the children's age (8-10 years) (ORa = 3.07 [1.49-6.29]; p = 0.004); and the profession of the head of household (retailer/employee versus farmer) (ORa = 2.71 [1.34-5.48]; p = 0.006). Previously seeking care (ORa = 0.28 [0.105-0.736], p=0.001] satisfaction with received information (ORa = 0.45 [0.24-0.84]; p = 0.013), and the quality of history taking (ORa = 0.38 [0.21-0.69]; p = 0.001) were significantly associated with good compliance. CONCLUSION: The results of the study show the importance of information and communication between caregivers and health center staff. The experience gained from this therapeutic transition emphasizes the importance of information given to the patients at the time of the consultation and drug delivery in order to improve drug use and thus prevent the emergence of rapid drug resistance.

Biological measure of compliance to Artesunate plus Amodiaquine association: interest in a Mono-Desethyl-Amodiaquine blood assay?

The deployment of Artemisinin-based Combination Therapy for treating uncomplicated malaria poses problems in the patient compliance to these new treatments. The aim of our study was to investigate the relationship between compliance to 3 days treatment with Artesunate plus Amodiaquine (AS+AQ) and the Mono-Desethyl-Amodiaquine (MDA) blood concentration on the fourth day. A reference scale of mean MDA blood concentrations was constructed in 40 healthy adults. Each concentration corresponded to the MDA level on day 3 in a subject having one of the seven compliance degrees defined by the number and sequence of drug intakes from day 0 to day 2: one single dose on day 0, day 1 or day 2; two single doses separated by 24h, on day 0 and day 1 or on day 1 and day 2; two single doses separated by 48 h, on day 0 and day 2; three single doses, on day 0, day 1 and day 2. MDA was assayed in whole blood samples by HPLC. Non-parametric Mann and Whitney U tests were used for the comparison of two means. Our results demonstrated no clear relationship between the mean MDA blood concentrations on day 3 and compliance degrees, according to neither the number nor the sequence of doses taken. In particular, even though the differences were not significant, the mean concentration after three doses, expected to be the maximum, was unexpectedly lower than after two doses, on day 0 and day 1 or on day 1 and day 2. The high inter-individual variability of MDA concentrations attributed to the different rates of hepatic metabolism of each individual appears to have a greater effect on MDA levels than the number or timing of doses. Therefore, it seems that the role of a MDA blood assay is limited in use to discerning if none or one or more doses have been taken. A MDA assay do not allow to measure the compliance degree of one patient to AS+AQ association. Presently, interview and pill count following treatment seem to be the only tools available that may permit differentiation between degrees of compliance.

Trends in malaria morbidity following the introduction of artesunate plus amodiaquine combination in M'lomp village dispensary, south-western Senegal.

BACKGROUND: In Thailand, South Africa and Zanzibar, a decrease in malaria morbidity was observed following the introduction of artemisinin-based combination therapy (ACT). In Senegal, therapeutic trials supervised the in vivo efficacy of artesunate plus amodiaquine from 1999 to 2005 at the M'lomp village dispensary. The trends in malaria morbidity in this village were evaluated from 2000 to 2002. METHODS: Each year, between July and December inclusive, fevers treated with antimalarials and slide-proven, uncomplicated malaria cases were collected from dispensary health records. Data were also collected in 1998, just prior to ACT introduction. Pearson's chi square tests and Student tests were used to compare two percentages or two means respectively (alpha = 0.05). RESULTS: Between 1998 and 2002, the total number of fevers treated with antimalarials and their repetitiveness progressively decreased: From 2824 to 945 fevers and from 17.6% to 9.7% (RR1998-2002 = 0.55; [0.44-0.69]; p < 0.0001) respectively. Considering uncomplicated malaria cases only, a decrease was observed in their total number between 2001 and 2002, from 953 to 570 cases. The incidence rate and repetitiveness also decreased. The incidence rate fell from 46.1% in 2001 to 37.5% in 2002 (p < 0.0001) and the repetitiveness decreased from 13.0% in 2000 to 6.6% in 2002 (RR2000-2002 = 0.51; [0.35-0.72]; p = 0.0001). CONCLUSION: The percentage of uncomplicated malaria cases treated with ACT increased, from 18.9% in 2000 to 64.0% in 2002, making it tempting to conclude an impact on malaria morbidity. Nonetheless, the decline in incidence rate of uncomplicated malaria was slight and a lower recorded rainfall was reported in 2002 which could also explain this decline. The context in which ACT is introduced affects the impact on malaria morbidity. In M'lomp, in contrast to studies in Thailand, South Africa and Zanzibar, ACT coverage of malaria cases was low and no vector control measure was deployed. Moreover, the malaria transmission level is higher. In sub-Saharan countries, in order to optimize the impact on malaria morbidity, ACT deployment must be supported, on the one hand, by a strengthening of public health system to ensure a high ACT coverage and, on the other hand, by others measures, such vector control measures.

Adherence and effectiveness of drug combination in curative treatment among children suffering uncomplicated malaria in rural Senegal.

Increased Plasmodium falciparum resistance to chloroquine has prompted national malaria programs to develop new policies in several African countries. Less than a year after the introduction of amodiaquine/sulfadoxine-pyrimethamine (AQ/SP) as first-line treatment in Senegal, we examined adherence rates to therapy and its efficacy among children. The study was conducted in five dispensaries in rural Senegal. Children aged 2-10 years with a presumptive diagnosis of malaria were prescribed AQ/SP. Thick blood film analyses were carried out on days 0, 3, 7, 14 and 28. Blood and urine samples were collected on day 3 for drug level measurements. The principal caregivers were questioned on treatment adherence. Among the 289 recruited children, 144 had a parasitemia >2500/microl. The results demonstrated markedly good efficacy for the treatment, as no detectable parasitemia was observed on day 28 for 97.9% of the children. However, we noticed that 35.3% of children did not comply with the recommended doses and 62.3% did not exactly adhere to the drug schedule. Despite the good efficacy of the drugs, adherence to the therapeutic scheme was poor. Strategies to promote patient adherence would improve drug performance and thus might help to prevent the rapid emergence of drug resistance.

The impact of IgG antibodies to recombinant Plasmodium falciparum 732var CIDR-1alpha domain in mothers and their newborn babies.

Different domains of a novel full-length var gene (termed 732var) isolated from a placenta of a malaria-infected woman were expressed in Escherichia coli as recombinant proteins and analysed biochemically and immunologically. Two of these, the Duffy binding-like (DBL)-3gamma domain and the cysteine-rich interdomain region (CIDR)-1alpha were able to bind chondroitin sulfate A and CD36, respectively. The DBL-3gamma domain was investigated in a previous study and confirmed here to exhibit anti-disease characteristics related to pregnancy-associated malaria. Mothers with high anti-DBL-3gamma antibody levels were protected from placental infection. The novel finding in this study is that babies born to mothers carrying anti-CIDR-1alpha antibodies had a delayed time to the first infection.