[Show abstract][Hide abstract] ABSTRACT: Antibiotic resistance is a threat in developing countries (DCs) because of the high burden of bacterial disease and the presence of risk factors for its emergence and spread. This threat is of particular concern for neonates in DCs where over one-third of neonatal deaths may be attributable to severe infections and factors such as malnutrition and HIV infection may increase the risk of death. Additional, undocumented deaths due to severe infection may also occur due to the high frequency of at-home births in DCs.
We conducted a systematic review of studies published after 2000 on community-acquired invasive bacterial infections and antibiotic resistance among neonates in DCs. Twenty-one articles met all inclusion criteria and were included in the final analysis.
Ninety percent of studies recruited participants at large or university hospitals. The majority of studies were conducted in Sub-Saharan Africa (n = 10) and the Indian subcontinent (n = 8). Neonatal infection incidence ranged from 2.9 (95% CI 1.9-4.2) to 24 (95% CI 21.8-25.7) for 1000 live births. The three most common bacterial isolates in neonatal sepsis were Staphylococcus aureus, Escherichia coli, and Klebsiella. Information on antibiotic resistance was sparse and often relied on few isolates. The majority of resistance studies were conducted prior to 2008. No conclusions could be drawn on Enterobacteriaceae resistance to third generation cephalosporins or methicillin resistance among Staphylococcus aureus.
Available data were found insufficient to draw a true, recent, and accurate picture of antibiotic resistance in DCs among severe bacterial infection in neonates, particularly at the community level. Existing neonatal sepsis treatment guidelines may no longer be appropriate, and these data are needed as the basis for updated guidelines. Reliable microbiological and epidemiological data at the community level are needed in DCs to combat the global challenge of antibiotic resistance especially among neonates among whom the burden is greatest.
[Show abstract][Hide abstract] ABSTRACT: Previous population-based studies have identified increased suicide rates among cancer patients. Available post mortem data on the contribution of cancer to completed suicide are limited, however. This study examines forensic autopsy data in order to assess whether cancer is significantly more frequent in a suicide population compared with a control population. In total, 232 cases were included in both the suicide and the control groups. Based on a complete standard histological examination, cancer was significantly more often found in the suicide group than in the control one (8.6% vs. 3.9%, p=0.03). The multivariate analysis also showed that the presence of cancer increased the risk of suicide. Moreover, cancer was not known to the deceased in 70% of cases, while the most frequent mental disease found in cancer-related suicide cases was depression (75%). In the 20 cancer-related suicide cases analysed herein, it was difficult to ascertain whether malignancy was the only motive for committing suicide, as cancer could be considered to be either a major causative factor for suicide or an incidental finding. Therefore, further research is warranted with the help of the psychological autopsy method to investigate the link between suicide and cancer further.
Medical Hypotheses 11/2013; 82(1). DOI:10.1016/j.mehy.2013.10.025 · 1.07 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The antibiotic overconsumption is the main force driving the emergence of multidrug-resistant bacterial strains. To promote better antibiotic use in France, a nationwide campaign is run every year from October to March since 2002. In 2007, it was shown that the winter outpatient antibiotic consumption had decreased by 26.5% compared to the 2000-2002 baseline period. Herein, we quantified outpatient antibiotic use between 2000 and 2010, as follow-up analysis of the nationwide campaign. Reimbursed outpatient antibiotic prescriptions were extracted from computerized French National Health Insurance databases. Entire series, and by age group and antibiotic class analyses were computed. Time-series analyses used autoregressive moving-average models with exogenous variables and intervention functions. Two periods were considered: October-March "campaign" periods and April-September "warm" periods. Compared to the pre-campaign (2000-2002) baseline period, the numbers of weekly antibiotic prescriptions per 1,000 inhabitants during campaign periods decreased until winter 2006-2007 (-30% [95% CI, -36.3 to 23.8]; P < 0.001) and then stabilized except for those >60 years, for whom prescriptions reached the pre-campaign level. During April-September warm periods, no significant differences were estimated compared to the baseline level for the entire series, but seniors had an increasing trend that became significant as of 2005, reaching +21% [95% CI, +12.9 to +29.6] in 2009 (P < 0.0001). These results highlight the need for a better understanding of antibiotic use by the elderly, requiring research with targeted and tailored public health actions for this population.
[Show abstract][Hide abstract] ABSTRACT: PurposeTo investigate the interest of post-mortem ultrasonography in the diagnosis of pathological background, and manner and cause of death.Methods
Post-mortem ultrasonography exams were carried out on 38 fresh human adult cadavers referred to the Department of Forensic Medicine and Pathology (Garches, France). Data obtained from ultrasonography were independently compared with further forensic autopsy findings.ResultsTwo important limitations relative to ultrasound utilization appeared: hyper-echoic abdominal and thoracic walls, with gas distension of the whole digestive tube and subcutaneous tissues (due to precocious putrefactive gas releasing); and difficulty in accessing lateral and posterior structures (i.e. liver, spleen, kidneys, lung bases, aorta) due to rigor mortis and evident non-compliance of the subject. Post-mortem diagnoses (moderate ascites, gallbladder stones, bladder globe, chronic kidney disease, cirrhosis, thyroid gland cysts and hypertrophy, intrauterine device), were strongly limited. False negative diagnoses comprised fatty liver, pleural effusion, thoracic aortic dissection, and focal organ and/or soft tissues lesions (for example, wounds or infarcts).Conclusion
According to the results, post-mortem ultrasonography seems to have a very limited role for forensic purposes. Other post-mortem utilizations are cited, proposed, and discussed.
Medicine, science, and the law 08/2013; 53(4). DOI:10.1177/0025802413479946 · 0.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of our study was to determine the frequency and nature of testicular and paratesticular lesions in forensic autopsies. A retrospective study was carried out on 495 adult male cases that underwent forensic autopsy from January 2008 to December 2011 in our Department. For each case, the following parameters were reported: age, body mass index, nature of testicular and paratesticular lesions, associated lesions in external genitalia, testicle weight, cause of death, manner of death, resuscitation attempts and prior medical history. Mean age of the studied population was 47.8 years (range 18-96). Mean body mass index was 25.3 kg/m(2) (range 15-46.2). Testicular lesions and/or paratesticular were found in 16.4% of the cases (n = 81). The most frequent lesions were, respectively, testicular atrophy (n = 38) and trauma (n = 28). In three cases showing traumatic lesions, associated traumatic lesions were found in external genitalia. Most frequent cause of death was blunt trauma (19.9% of the cases). Manner of death most frequently associated with testicular trauma was, respectively, road traffic accident (n = 11) and suicidal fall (n = 6). Mean testicular weight was, respectively, 17.9 g for the right and 20.8 g for the left (range 2-38). Atrophy was associated with testicular weight less than 10 g. A significant association between testicular atrophy and age was found, the risk of atrophy increasing quite linearly with age. No significant statistical link between prior medical history and testicular pathology was found. There was also no influence of body mass index. Resuscitation attempts were not statistically associated with testicular traumatic lesions.
Medicine, science, and the law 08/2013; 53(4). DOI:10.1177/0025802412473598 · 0.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In France, the 2009 A(H1N1) influenza epidemic occurred between September 2009 and January 2010. Sparking widespread controversy, it was intensely reported in the media. Despite therapeutic inefficacy, antibiotic consumption and viral respiratory infections are positively correlated, particularly in France, where antibiotic overconsumption is well-known. We first determined the period when media coverage was high, and then compared, during this period, observed outpatient antibiotic consumption to estimated outpatient antibiotic consumption "without media attention".
TO EVALUATE MEDIA COVERAGE, TWO ONLINE DATABASES WERE CONSULTED: Factiva and Europresse. To quantify outpatient antibiotic consumption, we used data on reimbursements of outpatient systemic antibiotics from the computerized databases of the two main National Health Insurance agencies. Influenza-like syndromes data came from the French GPs Sentinelles Network. Weekly time-series of antibiotic consumption were modeled by autoregressive moving-average models with exogenous inputs and interventions. Analyses were computed for the entire series and by age group (0-5, 6-15, 16-60, and >60 years).
Media coverage was intense between April 2009 and January 2010. No effect on total outpatient antibiotic consumption was observed during the whole mediatic period. However, during the epidemic in France (September 2009-January 2010), we found an antibiotic underconsumption for the entire series, 0-5 and >60 years. Additionally, at the beginning of the pandemic, when cases were still outside France (June 2009-August 2009), we found an antibiotic overconsumption for patients >16 years.
The early period of A(H1N1) virus circulation compared with seasonal influenza or an overdeclaration of ILS cases might explain the antibiotic underconsumption observed during the period of active A(H1N1) virus transmission in France. At the pandemic onset, when uncertainty was high, the overconsumption observed for individuals >16 years might have been caused by alarmist media reporting. Additional analyses are needed to understand the determinants of antibiotic consumption during this period.
PLoS ONE 07/2013; 8(7):e69075. DOI:10.1371/journal.pone.0069075 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Pneumococcus is an important human pathogen, highly antibiotic resistant and a major cause of bacterial meningitis worldwide. Better prevention requires understanding the drivers of pneumococcal infection incidence and antibiotic susceptibility. Although respiratory viruses (including influenza) have been suggested to influence pneumococcal infections, the underlying mechanisms are still unknown, and viruses are rarely considered when studying pneumococcus epidemiology. Here, we propose a novel mathematical model to examine hypothetical relationships between Streptococcus pneumoniae meningitis incidence (SPMI), acute viral respiratory infections (AVRIs) and antibiotic exposure. French time series of SPMI, AVRI and penicillin consumption over 2001-2004 are analysed and used to assess four distinct virus-bacteria interaction submodels, ascribing the interaction on pneumococcus transmissibility and/or pathogenicity. The statistical analysis reveals strong associations between time series: SPMI increases shortly after AVRI incidence and decreases overall as the antibiotic-prescription rate rises. Model simulations require a combined impact of AVRI on both pneumococcal transmissibility (up to 1.3-fold increase at the population level) and pathogenicity (up to threefold increase) to reproduce the data accurately, along with diminished epidemic fitness of resistant pneumococcal strains causing meningitis (0.97 (0.96-0.97)). Overall, our findings suggest that AVRI and antibiotics strongly influence SPMI trends. Consequently, vaccination protecting against respiratory virus could have unexpected benefits to limit invasive pneumococcal infections.
Proceedings of the Royal Society B: Biological Sciences 06/2013; 280(1764):20130519. DOI:10.1098/rspb.2013.0519 · 5.05 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Salmonella are the most common bacterial cause of foodborne infections in France and ubiquitous pathogens present in many animal productions. Assessing the relative contribution of the different food-animal sources to the burden of human cases is a key step towards the conception, prioritization and assessment of efficient control policy measures. For this purpose, we considered a Bayesian microbial subtyping attribution approach based on a previous published model (Hald et al., 2004). It requires quality integrated data on human cases and on the contamination of their food sources, per serotype and microbial subtype, which were retrieved from the French integrated surveillance system for Salmonella. The quality of the data available for such an approach is an issue for many countries in which the surveillance system has not been designed for this purpose. In France, the sources are monitored simultaneously by an active, regulation-based surveillance system that produces representative prevalence data (as ideally required for the approach) and a passive system relying on voluntary laboratories that produces data not meeting the standards set by Hald et al. (2004) but covering a broader range of sources. These data allowed us to study the impact of data quality on the attribution results, globally and focusing on specific features of the data (number of sources and contamination indicator). The microbial subtyping attribution model was run using an adapted parameterization previously proposed (David et al., 2012). A total of 9076 domestic sporadic cases were included in the analyses as well as 9 sources among which 5 were common to the active and the passive datasets. The greatest impact on the attribution results was observed for the number of sources. Thus, especially in the absence of data on imported products, the attribution estimates presented here should be considered with caution. The results were comparable for both types of surveillance, leading to the conclusion that passive data constitute a potential cost-effective complement to active data collection, especially interesting because the former encompass a greater number of sources. The model appeared robust to the type of surveillance, and provided that some methodological aspects of the model can be enhanced, it could also serve as a risk-based guidance tool for active surveillance systems.
Preventive Veterinary Medicine 02/2013; 110(1). DOI:10.1016/j.prevetmed.2013.02.002 · 2.17 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BackgroundTwo years after implementing the free-CS policy, we assessed the non-financial factors associated with caesarean section (CS) in women managed by referral hospitals in Senegal and Mali.MethodsWe conducted a cross-sectional survey nested in a cluster trial (QUARITE trial) in 41 referral hospitals in Senegal and Mali (10/01/2007–10/01/2008). Data were collected regarding women’s characteristics and on available institutional resources. Individual and institutional factors independently associated with emergency (before labour), intrapartum and elective CS were determined using a hierarchical logistic mixed model.ResultsAmong 86 505 women, 14% delivered by intrapartum CS, 3% by emergency CS and 2% by elective CS. For intrapartum, emergency and elective CS, the main maternal risk factors were, respectively: previous CS, referral from another facility and suspected cephalopelvic-disproportion (adjusted Odds Ratios from 2.8 to 8.9); vaginal bleeding near full term, hypertensive disorders, previous CS and premature rupture of membranes (adjusted ORs from
3.9 to 10.2); previous CS (adjusted OR=19.2 [17.2-21.6]). Access to adult and neonatal intensive care, a 24-h/day anaesthetist and number of annual deliveries per hospital were independent factors that affected CS rates according to degree of urgency. The presence of obstetricians and/or medical-anaesthetists was associated with an increased risk of elective CS (adjusted ORs [95%CI] = 4.8 [2.6-8.8] to 9.4 [5.1-17.1]).ConclusionsWe confirm the significant effect of well-known maternal risk factors affecting the mode of delivery. Available resources at the institutional level and the degree of urgency of CS should be taken into account in analysing CS rates in this context.
[Show abstract][Hide abstract] ABSTRACT: In the context of rapid changes regarding practices related to delivery in Africa, we assessed maternal and perinatal adverse outcomes associated with the mode of delivery in 41 referral hospitals of Mali and Senegal.
Cross-sectional survey nested in a randomised cluster trial (1/10/2007-1/10/2008). The associations between intended mode of delivery and (i) in-hospital maternal mortality, (ii) maternal morbidity (transfusion or hysterectomy), (iii) stillbirth or neonatal death before Day 1 and (iv) neonatal death between 24 hours after birth and hospital discharge were examined. We excluded women with immediate life threatening maternal or fetal complication to avoid indication bias. The analyses were performed using hierarchical logistic mixed models with random intercept and were adjusted for women's, newborn's and hospitals' characteristics.
Among the 78,166 included women, 2.2% had a pre-labor cesarean section (CS) and 97.8% had a trial of labor. Among women with a trial of labor, 87.5% delivered vaginally and 12.5% had intrapartum CS. Pre-labor CS was associated with a marked reduction in the risk of stillbirth or neonatal death before Day 1 as compared with trial of labor (OR = 0.2 [0.16-0.36]), though we did not show that maternal mortality (OR = 0.3 [0.07-1.32]) and neonatal mortality after Day 1 (OR = 1.3 (0.66-2.72]) differed significantly between groups. Among women with trial of labor, intrapartum CS and operative vaginal delivery were associated with higher risks of maternal mortality and morbidity, and neonatal mortality after Day 1, as compared with spontaneous vaginal delivery.
In referral hospitals of Mali and Senegal, pre-labor CS is a safe procedure although intrapartum CS and operative vaginal delivery are associated with increased risks in mothers and infants. Further research is needed to determine what aspects of obstetric care contribute to a delay in the provision of intrapartum interventions so that practices may be made safer when they are needed.
PLoS ONE 10/2012; 7(10):e47352. DOI:10.1371/journal.pone.0047352 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Attributing foodborne illnesses to food sources is essential to conceive, prioritize, and assess the impact of public health policy measures. The Bayesian microbial subtyping attribution model by Hald et al. is one of the most advanced approaches to attribute sporadic cases; it namely allows taking into account the level of exposure to the sources and the differences between bacterial types and between sources. This step forward requires introducing type and source-dependent parameters, and generates overparameterization, which was addressed in Hald's paper by setting some parameters to constant values. We question the impact of the choices made for the parameterization (parameters set and values used) on model robustness and propose an alternative parameterization for the Hald model. We illustrate this analysis with the 2005 French data set of non-typhi Salmonella. Mullner's modified Hald model and a simple deterministic model were used to compare the results and assess the accuracy of the estimates. Setting the parameters for bacterial types specific to a unique source instead of the most frequent one and using data-based values instead of arbitrary values enhanced the convergence and adequacy of the estimates and led to attribution estimates consistent with the other models' results. The type and source parameters estimates were also coherent with Mullner's model estimates. The model appeared to be highly sensitive to parameterization. The proposed solution based on specific types and data-based values improved the robustness of estimates and enabled the use of this highly valuable tool successfully with the French data set.
[Show abstract][Hide abstract] ABSTRACT: Disturbances in some endocrine hormones have been implicated in the pathophysiology of depression and psychosis. We consider here further the hypothesis that there may be a correlation between suicide risk and the weight of the thyroid gland. The thyroid weight and other relevant information (sex, BMI) were collected retrospectively from 576 autopsies including 299 cases of completed suicide, analyzed in the west area of Paris between 1994 and 2010. Multiple regression model, adjusted on sex and BMI, confirmed that only for subjects more than 60 years of age, deceased by suicide, had a significant decrease in their weight of thyroid compared to those who deceased for another cause (decrease of around 3g, p=0.03, for age class 60 and over). Our hypothesis is that there could exist an anatomical correlate (thyroid weight) among people who have committed suicide, especially old individuals. Various hypotheses regarding the hypothalamus-pituitary-thyroid axis dysfunction and the physiopathology of major depression are proposed and discussed. Further studies will be necessary in order to confirm that such a tendency exists on other populations.
Medical Hypotheses 05/2012; 79(2):264-6. DOI:10.1016/j.mehy.2012.05.005 · 1.07 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of our study was to analyze hemorrhagic lesions of the rectal wall in hanging autopsy cases. All autopsy reports regarding hanging from January 1st, 2008 to December 31st, 2010 were retrospectively reviewed. One hundred and two hanging cases were selected out of 1379 autopsy cases. Rectal wall hemorrhage was found in about 4% of the cases (n=4). Two of these 4 cases (50%) were associated with bowel wall hemorrhage, suggesting a similar possible etiology by abdominal congestion during the agonal phase. Another etiology could be an hemorrhagic lividity in the rectum. As it is not possible to determine with certainty the etiology, even with the use of histology, the detection of rectal wall hemorrhage cannot be used as another sign of vital hanging. Such rectum changes raise the possibility of sexual assault. Forensic pathologists should be aware of such an occurrence and avoid potential harmful misinterpretation.
Legal Medicine 02/2012; 14(4):172-6. DOI:10.1016/j.legalmed.2012.01.011 · 1.24 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Do all clinical research publications show strong application of ethics principles and respect for biomedical law? We examined, for the year 2009, the ethics requirements displayed on the website of 30 leading medical journals with an impact factor (IF) >10, and 30 others with an IF <10. We carried out a short study looking at the relationship between the IF of a journal and the ethics requirements in its instructions to authors. We show that the IF of a biomedical journal bears a direct relationship to its ethics requirements. Such results should improve the ethics requirements of all biomedical journals, especially those with low IF, so that they are internationally standardised to the higher standard required by journals with higher IF.
Journal of medical ethics 12/2011; 38(4):253-5. DOI:10.1136/medethics-2011-100174 · 1.51 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To determine the effect of maternal anaemia on pregnancy outcome and describe its impact on infant haemoglobin level in the first 18 months of life, we conducted a prospective study of 617 pregnant women and their children in Benin. Prevalence of maternal anaemia at delivery was 39.5%, and 61.1% of newborns were anaemic at birth. Maternal anaemia was not associated with low birth weight [OR = 1.2 (0.6–2.2)] or preterm birth [OR = 1.3 (0.7–2.4)], whereas the newborn’s anaemia was related to maternal anaemia [OR = 1.8 (1.2–2.5)]. There was no association between an infant’s haemoglobin level until 18 months and maternal anaemia. However, malaria attacks during follow-up, male gender and sickle cell trait were all associated with a lower infant haemoglobin level until 18 months, whereas good infant feeding practices and a polygamous family were positively associated with a higher haemoglobin level during the first 18 months of life.
Pour déterminer l’effet de l’anémie maternelle sur les résultats de la grossesse et décrire son impact sur le taux d’hémoglobine du nourrisson dans les 18 premiers mois de la vie, nous avons mené une étude prospective portant sur 617 femmes enceintes et leurs enfants au Bénin. La prévalence de l’anémie maternelle à l’accouchement était de 39.5% et 61.1% des nouveau-nés étaient anémiques à la naissance. L’anémie maternelle n’était pas associée avec le faible poids de naissance [OR = 1.2 (0.6 à 2.2)] ou la prématurité [OR = 1.3 (0.7 à 2.4)], alors que l’anémie du nouveau-néétait liée à l’anémie maternelle [OR = 1.8 (1.2 à 2.5)]. Il n’y avait aucune association entre le taux d’hémoglobine d’un nourrisson jusqu’à 18 mois et l’anémie maternelle. Cependant, les attaques de paludisme au cours du suivi, le sexe masculin et le trait drépanocytaire étaient tous associés à des taux plus faibles de l’hémoglobine du nourrisson jusqu’à 18 mois, alors que les bonnes pratiques d’alimentation du nourrisson et une famille polygame étaient positivement associées à des taux plus élevés de l’hémoglobine au cours des 18 premiers mois de la vie.
Con el fin de determinar el efecto de la anemia materna sobre el resultado del embarazo y describir su impacto sobre los niveles de hemoglobina del lactante durante los primeros 18 meses de vida, hemos realizado un estudio prospectivo con 617 mujeres embarazadas y sus bebes en Benin. La prevalencia de la anemia materna en el momento del parto era del 39.5%, y al nacer un 61.1% de los recién nacidos eran anémicos. La anemia materna no estaba asociada con un bajo peso al nacer [OR = 1.2 (0.6–2.2)] o con un parto prematuro [OR = 1.3 (0.7–2.4)], mientras que la anemia en los recién nacidos estaba relacionada con la anemia materna [OR = 1.8 (1.2–2.5)]. No había una asociación entre los niveles de hemoglobina del lactante hasta los 18 meses y la anemia materna. Sin embargo, los ataques de malaria durante el seguimiento, el ser de género masculino y el rasgo de células falciformes, estaban todas asociadas con un menor nivel de hemoglobina en el lactante hasta los 18 meses, mientras que una buena práctica de alimentación y el pertenecer a una familia polígama estaban asociados de forma positiva con un mayor nivel de hemoglobina durante los primeros 18 meses de vida.
Tropical Medicine & International Health 12/2011; 17(3):283-291. DOI:10.1111/j.1365-3156.2011.02932.x · 2.33 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The association between placental malaria (PM) and first peripheral parasitaemias in early infancy was assessed in Tori Bossito, a rural area of Benin with a careful attention on transmission factors at an individual level.
Statistical analysis was performed on 550 infants followed weekly from birth to 12 months. Malaria transmission was assessed by anopheles human landing catches every 6 weeks in 36 sampling houses and season defined by rainfall. Each child was located by GPS and assigned to the closest anopheles sampling house. Data were analysed by survival Cox models, stratified on the possession of insecticide-treated mosquito nets (ITNs) at enrolment.
Among infants sleeping in a house with an ITN, PM was found to be highly associated to first malaria infections, after adjusting on season, number of anopheles, antenatal care (ANC) visits and maternal severe anaemia. Infants born from a malaria infected placenta had a 2.13 fold increased risk to present a first malaria infection than those born from a non infected placenta ([1.24-3.67], p<0.01) when sleeping in a house with an ITN. The risk to present a first malaria infection was increased by 3.2 to 6.5, according to the level of anopheles exposure (moderate or high levels, compared to the absence of anopheles).
First malaria infections in early childhood can be attributed simultaneously to both PM and high levels of exposure to infected anopheles. Protective measures as Intermittent Preventive Treatment during pregnancy (IPTp) and ITNs, targeted on both mothers and infants should be reinforced, as well as the research on new drugs and insecticides. In parallel, investigations on placental malaria have to be strengthened to better understand the mechanisms involved, and thus to protect adequately the infants high risk group.
PLoS ONE 11/2011; 6(11):e27516. DOI:10.1371/journal.pone.0027516 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: High antibody levels directed to Plasmodium falciparum merozoite surface proteins (MSP), including MSP2, as well as genetically related red blood cell defects, have previously been found to be associated with protection against malaria. Here, our main objective was to study the changes in MSP2-specific total IgG, IgG1 and IgG3 responses during a malaria transmission season in order to assess the impact of sickle-cell, α(+)-thalassemia and G6PD variants on antibody kinetics. Repeated parasitological assessments of a cohort of children were conducted during an 8-month period. Antibody responses to recombinant MSP2/3D7 and MSP2/FC27 proteins were measured at the beginning and at the end of transmission season. We found that (i) the period of last Plasmodium falciparum infection during the transmission season was associated with IgG3 anti-MSP2 change. Compared to the IgG3 levels of children infected in January 2003 (end of transmission season), the IgG3 level of children decreased with the length of the period without infection, (ii) G6PD A- carriers had a lower increase of IgG3 levels to MSP2/FC27 and MSP2/3D7 during the transmission season than the noncarriers. This latter finding is suggestive of qualitative and/or quantitative reduction of exposure to malarial antigens related to this genetic variant, leading to weaker stimulation of specific antibody responses. We speculate that cell-mediated immune activity may explain the clinical protection afforded by this genetic trait.
Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 04/2011; 11(6):1287-92. DOI:10.1016/j.meegid.2011.04.016 · 3.02 Impact Factor