Proof-of-principle of onchocerciasis elimination with ivermectin treatment in endemic foci in Africa: final results of a study in Mali and Senegal.

BACKGROUND: Mass treatment with ivermectin controls onchocerciasis as a public health problem, but it was not known if it could also interrupt transmission and eliminate the parasite in endemic foci in Africa where vectors are highly efficient. A longitudinal study was undertaken in three hyperendemic foci in Mali and Senegal with 15 to 17 years of annual or six-monthly ivermectin treatment in order to assess residual levels of infection and transmission, and test whether treatment could be safely stopped. This article reports the results of the final evaluations up to 5 years after the last treatment. METHODOLOGY/PRINCIPAL FINDINGS: Skin snip surveys were undertaken in 131 villages where 29,753 people were examined and 492,600 blackflies were analyzed for the presence of Onchocerca volvulus larva using a specific DNA probe. There was a declining trend in infection and transmission levels after the last treatment. In two sites the prevalence of microfilaria and vector infectivity rate were zero 3 to 4 years after the last treatment. In the third site, where infection levels were comparatively high before stopping treatment, there was also a consistent decline in infection and transmission to very low levels 3 to 5 years after stopping treatment. All infection and transmission indicators were below postulated thresholds for elimination. CONCLUSION/SIGNIFICANCE: The study has established the proof of principle that onchocerciasis elimination with ivermectin treatment is feasible in at least some endemic foci in Africa. The study results have been instrumental for the current evolution from onchocerciasis control to elimination in Africa.

Feasibility of onchocerciasis elimination with ivermectin treatment in endemic foci in Africa: first evidence from studies in Mali and Senegal.

BACKGROUND: Mass treatment with ivermectin is a proven strategy for controlling onchocerciasis as a public health problem, but it is not known if it can also interrupt transmission and eliminate the parasite in endemic foci in Africa where vectors are highly efficient. A longitudinal study was undertaken in three hyperendemic foci in Mali and Senegal with 15 to 17 years of annual or six-monthly ivermectin treatment in order to assess residual levels of infection and transmission and test whether ivermectin treatment could be safely stopped in the study areas. METHODOLOGY/PRINCIPAL FINDINGS: Skin snip surveys were undertaken in 126 villages, and 17,801 people were examined. The prevalence of microfilaridermia was <1% in all three foci. A total of 157,500 blackflies were collected and analyzed for the presence of Onchocerca volvulus larvae using a specific DNA probe, and vector infectivity rates were all below 0.5 infective flies per 1,000 flies. Except for a subsection of one focus, all infection and transmission indicators were below postulated thresholds for elimination. Treatment was therefore stopped in test areas of 5 to 8 villages in each focus. Evaluations 16 to 22 months after the last treatment in the test areas involved examination of 2,283 people using the skin snip method and a DEC patch test, and analysis of 123,000 black flies. No infected persons and no infected blackflies were detected in the test areas, and vector infectivity rates in other catching points were <0.2 infective flies per 1,000. CONCLUSION/SIGNIFICANCE: This study has provided the first empirical evidence that elimination of onchocerciasis with ivermectin treatment is feasible in some endemic foci in Africa. Although further studies are needed to determine to what extent these findings can be extrapolated to other endemic areas in Africa, the principle of elimination has been established. The African Programme for Onchocerciasis Control has adopted an additional objective to assess progress towards elimination endpoints in all onchocerciasis control projects and to guide countries on cessation of treatment where feasible.

[Relevance of the toxoplasma IgG avidity test in the serological surveillance of pregnant women]. / Intérêt de l'indice d'avidité des IgG pour le diagnostic d'exclusion d'une toxoplasmose récente : comparaison de la trousse Toxo IgG Avidité SFRI à la trousse Toxo IgG Avidity Vidas.

In addition to the serological systematic screening tests, kits to measure the avidity of toxoplasma IgG antibodies are currently available. Since high-avidity IgG toxoplasma antibodies have been shown to exclude recent infection, IgG avidity determination is especially useful in ruling out acute infection having occurred in the 3-4 prior months of pregnancy. We therefore compared the efficacy of two toxoplasma IgG avidity ELISA kits: SFRI (SFRI Laboratoire) and VIDAS Toxo-IgG avidity kit (bioMérieux). The agreement of the results from the 2 commercial assays were analysed using 55 serum samples, in terms of global mother-child Toxoplasma results and outcome, specially with light of the results of Toxoplasma antenatal, postnatal assays and of clinical follow up of children.

[A high troponin value: about a favourable evolution case]. / Valeur élevée de troponine: à propos d'un cas d'évolution favorable.

Cardiac troponin I (TnIC) is a sensitive and specific marker for myocardial injuries. A part from its diagnosis character, troponin is a major element for mid term prognosis with regard to occurred cardiovascular events. We are reporting the case of a 56-year-old man admitted to hospital for an inaugural myocardial infarction with positive evolution despite a very high level of troponin (1200 ng/ml) in post re-vascularisation. The context of moderate risk factors and the early re-vascularisation probably contributed to a favourable evolution of the patient. A very high troponin value seems to be more in favour of an effective re-perfusion rather than a mid term prognosis factor in this case.

[Real-time quantitative PCR for toxoplasmosis diagnosis]. / Apport de la PCR quantitative en temps réel dans le diagnostic de la toxoplasmose congénitale.

Congenital toxoplasmosis results from foetus contamination by Toxoplasma gondii during pregnancy. It is a frequent and severe condition calling for close monitoring of mothers at risk. During the last decades, numerous advances have been made specially in the antenatal diagnosis. The congenital toxoplasmosis diagnosis relies currently on PCR test of amniotic fluid, with a sensitivity of 80%. More recently, real-time quantitative PCR has been developed to improve toxoplasmosis diagnosis. We therefore compared the diagnosis value of quantitative real-time PCR with our conventional PCR-hybridization for the diagnosis of congenital toxoplasmosis.

[Relevance of anti-tissue transglutaminase antibodies in coeliac disease diagnosis]. / Intérêt des anticorps anti-transglutaminase tissulaire dans le diagnostic de la maladie coeliaque.

Coeliac disease is precipitated upon exposure to the dietary wheat gluten. Definitive diagnosis relies on intestinal biopsy and regression of clinical and histological disorders with adherence to a gluten-free diet. Coeliac disease is usually associated with a malabsorption syndrome. However, both atypical and silent clinical forms have been recently described and prevalence of the disease may be under-estimated. Serological tests have been developed in order to select candidates for intestinal biopsy, but these biological parameters are not suitable for screening in the general population. Indeed, antigliadin IgG antibodies have a poor specificity. antigliadin IgA antibodies a poor sensitivity. The detection of antiendomysial IgA antibodies (EmA) by immunofluorescence, although considered as the "gold standard" of serological coeliac disease markers, could not be automated, depends on a subjective fluorescence display, and may be limited by the degree of training of the observer. In year 1997, tissue transglutaminase (tTg) has been identified as the main autoantigen recognized by EmA. On this basis, solid-phase enzyme-linked immunosorbent assays (Elisa) have been developed in order to potentially replace the EmA assay. Several commercial kits are now available but their diagnostic performances have not yet been compared. We selected 75 sera, including sera from 26 patients with coeliac disease in order to evaluate five commercial anti-tTG Elisa kits. For all patients, treated or not, detection of anti-tTG antibodies with four of the five tested kits correlates with EmA test. Kits using human tTG have the highest specificity, equivalent to the value of EMA test, and widely better than antigliadin antibodies. Anti-tTG Elisa kits using human tTG may be used as an alternative way to the EmA assay in the next future, and may supplant IgA anti-gliadin antibodies for coeliac disease screening.

Hemoparasites des oiseaux sauvages a Madagascar

"Haemoparasites of wild birds in Madagascar"": This study aims to evaluate the prevalence and density of haemoparasites in native Malagasy birds. Among the 387 birds; belonging to 43 species sampled at six localities in different bio-climatic zones of the island; 139 (35.9"

[Hemoparasites in wild birds in Madagascar]. / Hémoparasites des oiseaux sauvages à Madagascar.

This study aims to evaluate the prevalence and density of haemoparasites in native Malagasy birds. Among the 387 birds, belonging to 43 species sampled at six localities in different bio-climatic zones of the island, 139 (35.9%) showed at least 1 hemoparasite with, by order of frequency, Plasmodium and/or Haemoproteus (19.9%), microfilariae (13.7% of 387 birds), Leucocytozoon (11.1%) and Trypanosoma (1.0%). An analysis to further elucidate these observations took into account the interaction of different environmental variables (altitude, season, site of collection) or aspects of the birds (age, weight, sex). There is evidence that some parasites preferentially infect some bird species or families. The largest male birds harboured the highest prevalences and densities of haemoparasite, regardless of species. These findings extend knowledge of bird/blood parasite relationships of Malagasy birds and provide interesting insights, especially concerning the pathogenicity of this type of parasitism and the parasite transmission by insect vectors.

[Neonatal hyperthyroidism in a premature infant born to a mother with Grave's disease]. / Hyperthyroïdie néonatale chez un prématuré né de mère atteinte d'une maladie de Basedow.

BACKGROUND: Neonatal thyrotoxicosis is most commonly due to transplacental transfer of maternal thyroid-stimulating hormone receptor antibodies (TRAb). Bioassay of thyrotropin receptor antibodies may help to determine the risk for neonatal hyperthyroidism. CASE REPORT: Thyrotoxicosis developed in a premature infant born to a mother with Graves' disease, with a low level of TRAb by bioassay. The infant was treated with carbimazole for two months, until TRAb had disappeared. CONCLUSION: Bioassay TRAb is not always reliable for predicting the development of neonatal hyperthyroidism in infants born to mothers with Graves' disease. Thyroid function should be measured in all these neonates.

[Hypoxic-ischemic encephalopathy in the full-term newborn. Contribution of electroencephalography and MRI or computed tomography to its prognostic evaluation. Apropos of 26 cases]. / Encéphalopathie hypoxo-ischémique du nouveau-né à terme. Apport de l'électroencéphalogramme et de l'IRM ou de la TDM à l'évaluation pronostique. A propos de 26 observations.

OBJECTIVES: Perinatal asphyxia complicated by hypoxic ischemic brain injury still remains the source of neurological lesions often serious and definitive. A major aim of neonatologists is to appreciate the severity of the hypoxic ischemic brain injury in the first days of life and to evaluate the forecast. The purpose of this work is to establish a relation between clinical signs, EEG, neuroimaging (MRI and CTS) and neuro-development. MATERIALS AND METHODS: 26 neonates from paediatric resuscitation unit (Hospital North, Marseille) were enrolled in a retrospective study since February 1994 to December 1997. All the newborns had at least one anamnestic criteria of perinatal asphyxia, an early electroencephalogram in the first two days of life and another between the third and the seventh day of life, and neuroimaging in the first 15 days of life: CTS in five cases and MRI in 21 cases. RESULTS: There was a good electro-clinic (P: 0.01) and prognostic (P: 0.03) correlation in patients within stage 3 of the "Sarnat classification". In the stage 2, the EEG did not provide valuable information about severity of the injury, and neuroimaging (especially MRI) allowed better prognosis. Diffuse brain injury or lesions of basal ganglia in MRI were associated, independently of clinical settings and EEG tracings, with a poor neurodevelopmental outcome (P: 0.02). The MRI was diagnostic in four cases of congenital encephalopathy complicated with neonatal suffering. CONCLUSION: Our study confirms the interest of the association of clinical settings, EEG tracings and MRI in the diagnosis and the prognostic of the hypoxic-ischemic encephalopathy in term neonate.