Anaemia in asymptomatic parasite carriers living in urban, rural and peri-urban settings of Gabon.

BACKGROUND: This cross-sectional study was carried out in different settlements of Gabon to determine the influence of single or multiple parasite carriage on haemoglobin (Hb) levels. METHODS: Between April 2015 and June 2016, healthy volunteers from urban, peri-urban and rural areas were screened for malaria, blood filariasis and intestinal parasitic infections using microscopic methods. Hb concentration was measured with a Hemocue analyser. The association between parasite carriage and anaemia was assessed. RESULTS: Among the 775 volunteers examined, 319 (41.2%) were from rural villages and 76.0% were adults. Filariasis, intestinal parasitic infections, Plasmodium falciparum and polyparasitism were detected in 15.6, 14.6, 9.5 and 6.8% of participants, respectively. Anaemia prevalence was 72.6%, with rates of mild, moderate and severe anaemia being 30.9, 61.1 and 8.0%, respectively. The median Hb level was lowest in the presence of hookworms (7.1 g/dl [interquartile range {IQR} 6.8-7.5]), Schistosoma intercalatum (6.9 g/dl), Trichuris trichiura (10.1 g/dl [IQR 8.9-11.5]) and Plasmodium falciparum (10.0 g/dl [IQR 9.1-11.2]) compared with filariaemia (12.1 g/dl [IQR 10.5-13.2]) (p=0.03). Moderate to severe anaemia predominated among those single-infected with P. falciparum (69.5%) or co-infected with intestinal parasitic infections and P. falciparum (76.2%), while it was found in only 23.2% of individuals with filariasis. All participants with soil-transmitted helminths and more than half with a Blastocystis sp. (68.8%) infection had moderate anaemia. CONCLUSIONS: The prevalence of anaemia is high. Asymptomatic parasite carriage is associated with anaemia in this surveyed population in Gabon.

Mid-infrared Mueller ellipsometer with pseudo-achromatic optical elements.

The purpose of this article is to present a new broadband Mueller ellipsometer designed to work in the mid-infrared range, from 3 to 14 µm. The Mueller ellipsometer, which can be mounted in reflection or in transmission configuration, consists of a polarization state generator (PSG), a sample holder, and a polarization state analyzer (PSA). The PSG consists of one linear polarizer and a retarder sequentially rotated to generate a set of four optimal polarization states. The retarder consists of a biprism made of two identical Fresnel rhombs disposed symmetrically and joined by an optical contact, giving the ensemble a "V" shape. Retardation is induced by the four total internal reflections that the beam undergoes when it propagates through the biprism. Total internal reflection allows the generation of a quasi-achromatic retardation. The PSA is identical to the PSG, but with its optical elements mounted in reverse order. After a measurement run, the instrument yields a set of sixteen independent values, which is the minimum amount of data required to calculate the Mueller matrix of the sample. The design of the Mueller ellipsometer is based on the optimization of an objective criterion that allows for minimizing the propagation of errors from raw data to the Mueller matrix of the sample. The pseudo-achromatic optical elements ensure a homogeneous quality of the measurements for all wavelengths. The performance of the Mueller ellipsometer, in terms of precision and accuracy, is discussed and illustrated with a few examples.

[Alternative medicine, beliefs, and management of people with HIV in Gabon]. / Médecines alternatives, croyances et prise en charge des personnes vivant avec le VIH au Gabon.

BACKGROUND: According to WHO, 80% of the population in Africa has used alternative medicine for primary health care at least once. Gabon continues to have a high prevalence of HIV, estimated in 2011 at 5.2%. Overall, 22 253 PLWHA (people living with HIV/AIDS) - adults and children - are being treated, including 9976 on ARVs (antiretroviral drugs). The procedures for ARV initiation are very long, ARVs are frequently out of stock, and treatment in care centers for PLWHA is stigmatized: all these factors favor the development of alternative medicine for HIV care in Gabon. OBJECTIVE: To analyze the impact of alternative medicine in the treatment of PLWHA in Gabon. METHODOLOGY: This cross-sectional survey was conducted during a total of four months between May 2009 and September 2010 among PLWHA older than 18 years who had been receiving ARVs for at least 6 months and consented to participate (7 centers) and among physicians and other caregivers of these centers (8 centers). We used a simple random sample method. Epidata software was used for data collection, and the analyses were performed with SAS™ software. RESULTS: Of the 5752 patients on ARVs followed at the 7 study sites, 422 PLWHA were interviewed (58.3% of them women): 284 (67.29%) in Libreville and 138 (38.7) in the provinces. Christians accounted for 90.5% (including 21.5% from Protestant evangelical churches), and Muslins for 5.68%, while 4% stated that they had no religion. 12.5% of doctors referred their patients to religious or spiritual groups. CONCLUSION: Our study showed that half of PLWHA did not know the procedures for access to ARV treatment and that beliefs about HIV/AIDS differed strongly according to place of residence. Finally, the cultural context related to alternative medicine is very present in the PLWHA treatment settings in Gabon. Although PLWHAs have easy access to ARVs, their association with organized and controlled alternative medicine can be beneficial.

Retardation assisted enhanced Raman scattering from silicon nanostripes in the visible range.

Patterned silicon on insulator structures representing evenly spaced parallel 15 nm-thick nanostripes exhibit an enhanced Raman scattering response when excited in the visible range in an oblique incidence backscattering configuration. The enhancement phenomenon in two structures having different stripe widths, 200 and 50 nm, is investigated at various sample azimuthal orientations, excitation radiation polarizations as well as laser wavelengths and is shown to be of resonant nature. The enhanced Raman response of the patterned structures is attributed to the presence of Mie resonances, essentially resulting in the enhancement of the internal electric field within the nanostripes. It is quantitatively described in terms of the spheroid particle model extended beyond the electrostatic limit to include field retardation effects that are shown to be responsible for the resonant behaviour in the visible range.

[National coordination of the ambulatory treatment centers (ATC) in Gabon: a new process to conduct the scaling up of care for people living with HIV-AIDS]. / La coordination nationale des centres de traitement ambulatoire au Gabon : une expérience novatrice de décentralisation opérationnelle de la prise en charge du VIH-sida.

Gabonese authorities are strongly mobilized in the fight against AIDS. With a national seroprevalence of 5.9%, 54,000 people are living with HIV-AIDS. Starting from the experience conducted on three ambulatory treatment centers (ATC) [Libreville, Franceville, Port-Gentil] in collaboration with the French Red Cross, Gabonese authorities decided the scaling up of HIV patients' care to seven new ATC at a national level. The increasing number of structures conducted to standardize treatment's guidelines, training of caregivers, quality of care, coordination, monitoring and evaluation. Technical and medical supervision of the ten ATC were attributed to the French Red Cross by Gabonese authorities with the financial support of the French Agency for Development. The ten ATC, founded by the ministry of public health, were then organized within a network under the responsibility of a national coordination. This structure created in September 2007 represents the main organism to conduct, evaluate and follow-up activities and functioning of the ten ATC. All these activities are conducted in agreement with the national program of fight against AIDS. Within one year this structure of coordination allowed to organize the training of 208 caregivers, to elaborate a team of national and international experts, to start a process of national guidelines, to elaborate technical procedures and indicators for monitoring, follow-up and evaluation. In June 2007, 5 ATC were in function taking care of 7,062 PLWA. In November 2008, 9 ATC were in function taking care of 8,174 PLWA. This project is planned for four years. It might allow to structure and organize a national network of care for PLWA according to the national strategy. This procedure of scaling up under the responsibility of a national team of technical and operational coordination is a new process. It completes and strengthens the national organization process.

[Clinical and laboratory findings in HIV-infected patients at the Jeanne Ebori Foundation in Libreville, Gabon (2002-2005)]. / Bilan clinico-biologique des patients infectés par le VIH à la Fondation Jeanne Ebori de Libreville (2002-2005).

The purpose of this study was to evaluate management of HIV-infected/AIDS patients within the framework of the ACCESS program at Center N 3 over a 4-year period. This retrospective single-center study included HIV-positive patients treated at the Jeanne Ebori Foundation in Libreville, Gabon between January 2002 and December 2005. The active file included 749 patients, i.e., 436 undergoing antiretroviral therapy and 313 with intention to treat. The population consisted mainly of city dwellers. Mean patient age was 38.8 years with a female predominance (sex ratio, 0.8). The highest incidence of infection was observed in the 20- to 30-year age group. Socioeconomic position was low in 63.2 % of patients. Clinical suspicion (67%) was the main reason for testing. In order of frequency, symptoms defined according to the WHO criteria were classified as stage B (33.5 %) and stage C (27.1%). Opportunistic infections were observed in 95% of cases: fungal: 57%, bacterial: 30.7%, and viral: 7.3%. Tritherapy, i.e., 2INTI + 1INNTI (72.9%) and 2INTI+1 IP (17.1%), was used in most cases. Treatment led to clinical improvement with a gradual, steady, and sustained increase in CD4 lymphocyte count. Adverse events were noted including gastrointestinal reactions (16%), neurological manifestations (12%), and general symptoms (12%). Concurrent disturbances in lipid levels and liver function were noted. Overall outcome was positive with a decrease in mortality from 39.2% (M0-M6) to 2.7% (M30-M36). The findings of this study show that improvement in socioeconomic conditions and availability of adequate diagnostic and therapeutic resources at management centers to obtain long-term control of HIV infection are still current issues.

Bilan clinico-biologique des patients infectes par le VIH a la fondation Jeanne Ebori de Libreville (2002-2005)

Notre etude a consiste a faire le bilan d'activites du centre no3 de prise en charge des patients infectes par l'infection a VIH/SIDA; dans le cadre du programme ACCESS. Il s'est agit d'une analyse retrospective; unicentrique; de patients VIH positifs realisee sur 4 ans de janvier 2002 a decembre 2005 a la Fondation Jeanne Ebori. La file active etait composee de 749 patients : 436 sous traitement antiretroviral et 313 en intention d'etre traiter. La population etait en majorite urbaine. L'age moyen des patients etait de 38;8 ans avec une predominance feminine (sex-ratio de 0;8). La tranche d'age la plus infectee etait celle dont l'age variait entre 20 et 50 ans. Le niveau socio-economique etait faible chez 63;2des malades. La suspicion clinique (67) etait le principal motif du test ; la symptomatologie etait selon la classification de l'OMS; par ordre de frequence : stade B (33;5) et stade C (27;1). La pathologie infectieuse opportuniste represente 95des cas (mycosique : 57; bacterienne : 30;7; virale :7;3). Les tritherapies incluant 2INTI + 1INNTI (72;9); 2INTI+1 IP (17;1) etaient les plus prescrites. L'efficacite du traitement antiretroviral s'etait traduite dans l'ensemble par une amelioration des parametres cliniques; une ascension reguliere; progressive et durable du taux de lymphocytes CD4. La survenue des effets indesirables a type de troubles digestifs (16); troubles neurologiques (12); signes generaux (12) etait notee. La perturbation des bilans lipidique et hepatique etait observee au cours du meme temps. Le bilan etait globalement positif avec une chute du taux de deces allant de 39;2(M0-M6) a 2;7(M30-M36). Ce travail montre que l'amelioration des conditions socio-economiques; l'approvisionnement equitable des centres de prise en charge en moyens diagnostiques et therapeutiques pour obtenir a long terme le controle de l'infection par le VIH; demeurent d'actualite