Effect of preventive chemotherapy with praziquantel on schistosomiasis among school-aged children in sub-Saharan Africa: a spatiotemporal modelling study

Background

Over the past 20 years, schistosomiasis control has been scaled up. Preventive chemotherapy with praziquantel is the main intervention. We aimed to assess the effect of preventive chemotherapy on schistosomiasis prevalence in sub-Saharan Africa, comparing 2000–10 with 2011–14 and 2015–19.

Methods

In this spatiotemporal modelling study, we analysed survey data from school-aged children (aged 5–14 years) in 44 countries across sub-Saharan Africa. The data were extracted from the Global Neglected Tropical Diseases database and augmented by 2018 and 2019 survey data obtained from disease control programmes. Bayesian geostatistical models were fitted to Schistosoma haematobium and Schistosoma mansoni survey data. The models included data on climatic predictors obtained from satellites and other open-source environmental databases and socioeconomic predictors obtained from various household surveys. Temporal changes in Schistosoma species prevalence were estimated by a categorical variable with values corresponding to the three time periods (2000–10, 2011–14, and 2015–19) during which preventive chemotherapy interventions were scaled up.

Findings

We identified 781 references with relevant geolocated schistosomiasis survey data for 2000–19. There were 19 166 unique survey locations for S haematobium and 23 861 for S mansoni, of which 77% (14 757 locations for S haematobium and 18 372 locations for S mansoni) corresponded to 2011–19. Schistosomiasis prevalence among school-aged children in sub-Saharan Africa decreased from 23·0% (95% Bayesian credible interval 22·1–24·1) in 2000–10 to 9·6% (9·1–10·2) in 2015–19, an overall reduction of 58·3%. The reduction of S haematobium was 67·9% (64·6–71·1) and that of S mansoni 53·6% (45·2–58·3) when comparing 2000–10 with 2015–19.

Interpretation

Our model-based estimates suggest that schistosomiasis prevalence in sub-Saharan Africa has decreased considerably, most likely explained by the scale-up of preventive chemotherapy. There is a need to consolidate gains in the control of schistosomiasis by means of preventive chemotherapy, coupled with other interventions to interrupt disease transmission.

Funding

European Research Council and WHO.

Safely resuming neglected tropical disease control activities during COVID-19: Perspectives from Nigeria and Guinea

Since its early spread in early 2020, the disease caused by the novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Coronavirus Disease 2019 (COVID-19) has caused mass disruptions to health services. These have included interruptions to programs that aimed to prevent, control, and eliminate neglected tropical diseases (NTDs). In March 2020, the World Health Organization (WHO) released interim guidelines recommending the temporary cessation of mass drug administration (MDA), community-based surveys, and case detection, while encouraging continuation of morbidity management and vector control where possible. Over the course of the following months, national programs and implementing partners contributed to COVID-19 response efforts, while also beginning to plan for resumption of NTD control activities. To understand the challenges, opportunities, and recommendations for maximizing continuity of disease control during public health emergencies, we sought perspectives from Nigeria and Guinea on the process of restarting NTD control efforts during the COVID-19 pandemic. Through semistructured interviews with individuals involved with NTD control at the local and national levels, we identified key themes and common perspectives between the 2 countries, as well as observations that were specific to each. Overall, interviewees stressed the challenges posed by COVID-19 interruptions, particularly with respect to delays to activities and related knock-on impacts, such as drug expiry and prolonged elimination timelines, as well as concerns related to funding. However, respondents in both countries also highlighted the benefits of a formal risk assessment approach, particularly in terms of encouraging information sharing and increasing coordination and advocacy. Recommendations included ensuring greater availability of historical data to allow better monitoring of how future emergencies affect NTD control progress; continuing to use risk assessment approaches in the future; and identifying mechanisms for sharing lessons learned and innovations between countries as a means of advancing postpandemic health systems and disease control capacity strengthening.

Neglected tropical diseases (NTDs) are a group of medically diverse diseases that affect over 1 billion people, predominantly in tropical and subtropical areas, and can cause severe long-term disability and even death. Controlled through mass drug administration (MDA), morbidity management, and/or vector control, NTD programs work closely with communities to identify cases, conduct surveys, and achieve target coverage levels for interventions. The advent of the pandemic of the novel Coronavirus Disease 2019 (COVID-19) in early 2020 led to major disruptions to all facets of life, including health services, with NTD control efforts no exception. Per interim guidelines released by the World Health Organization (WHO) in March 2020, most control activities were halted and only resumed much later in 2020. We sought perspectives from NTD control stakeholders at the subnational and national levels in Guinea and Nigeria regarding the process of planning and executing the resumption of NTD activities to identify challenges, opportunities, and recommendations that might be applicable both to other countries that have experienced disruptions to NTD control efforts during the pandemic and to increase the resilience of NTD programs in the face of future public health emergencies.

Restarting Neglected Tropical Diseases Programs in West Africa during the COVID-19 Pandemic: Lessons Learned and Best Practices

Countries across West Africa began reporting COVID-19 cases in February 2020. By March, the pandemic began disrupting activities to control and eliminate neglected tropical diseases (NTDs) as health ministries ramped up COVID-19–related policies and prevention measures. This was followed by interim guidance from the WHO in April 2020 to temporarily pause mass drug administration (MDA) and community-based surveys for NTDs. While the pandemic was quickly evolving worldwide, in most of West Africa, governments and health ministries took quick action to implement mitigation measures to slow the spread. The U.S. Agency for International Development’s (USAID) Act to End NTDs | West program (Act | West) began liaising with national NTD programs in April 2020 to pave a path toward the eventual resumption of activities. This process consisted of first collecting and analyzing COVID-19 epidemiological data, policies, and standard operating procedures across the program’s 11 countries. The program then developed an NTD activity restart matrix that compiled essential considerations to restart activities. By December 2020, all 11 countries in Act | West safely restarted MDA and certain surveys to monitor NTD prevalence or intervention impact. Preliminary results show satisfactory MDA program coverage, meaning that enough people are taking the medicine to keep countries on track toward achieving their NTD disease control and elimination goals, and community perceptions have remained positive. The purpose of this article is to share the lessons and best practices that have emerged from the adoption of strategies to limit the spread of the novel coronavirus during MDA and other program activities.

Implementation of mass drug administration for neglected tropical diseases in Guinea during the COVID-19 pandemic

BACKGROUND

Guinea reported its first case of COVID-19 on March 12, 2020. Soon thereafter, a national state of emergency was declared, all land borders were closed, schools were shut down, and public gatherings were limited. Many health activities, including field-based activities targeting neglected tropical diseases (NTDs), were paused. The World Health Organization (WHO) issued updated guidance on the resumption of NTD field-based activities on July 27, 2020. In response, the Guinea Ministry of Health (MoH) and its partners planned and resumed mass drug administration (MDA) in mid-August to September 2020 in 19 health districts.

METHODOLOGY/PRINCIPAL FINDINGS

A risk-benefit assessment was conducted to identify potential risks associated with the MDA in the COVID-19 context. Following this assessment, a risk mitigation plan with barrier measures was developed to guide MDA implementation. These measures included COVID-19 testing for all national staff leaving Conakry, mask wearing, social distancing of two meters, and hand washing/sanitizing. A checklist was developed and used to monitor compliance to risk mitigation measures. Data on adherence to risk mitigation measures were collected electronically during the MDA. A total of 120 checklists, representing 120 community drug distributor (CDD) teams (two CDDs per team) and 120 households, were completed. Results indicated that washing or disinfecting hands was practiced by 68.3% of CDD teams, compared to 45.0% among households. Face masks to cover the mouth and nose were worn by 79.2% of CDD teams, while this was low among households (23.3%). In 87.5% of households, participants did not touch the dose pole and in 88.3% of CDD teams, CDDs did not touch the hands of the participants while giving the drugs. A large majority of CDD teams (94.2%) and household members (94.2%) were willing to participate in the MDA despite the pandemic. The epidemiological coverage was ≥65% for lymphatic filariasis, onchocerciasis and soil-transmitted helminths in 10 out of 19 HDs and ≥75% for schistosomiasis for school-aged children in 7 out of 11 HDs.

CONCLUSIONS/SIGNIFICANCE

Guinea was one of the first countries in Africa to resume MDA activities during the COVID-19 pandemic without causing an observed increase of transmission. The development of a risk mitigation plan and a method to monitor adherence to barrier measures was critical to this unprecedented effort. The rapid incorporation of COVID-19 barrier measures and their acceptance by CDDs and household members demonstrated both the adaptability of the National NTD Program to respond to emerging issues and the commitment of the MoH to implement NTD programs.

Trachoma in the Democratic Republic of the Congo: Results of 46 Baseline Prevalence Surveys Conducted with the Global Trachoma Mapping Project

Purpose: Trachoma was suspected to be endemic in parts of the Democratic Republic of the Congo (DRC). We aimed to estimate prevalences of trachomatous inflammation–follicular (TF), trichiasis, and water and sanitation (WASH) indicators in suspected-endemic Health Zones.

Methods: A population-based prevalence survey was undertaken in each of 46 Health Zones across nine provinces of DRC, using Global Trachoma Mapping Project methods. A two-stage cluster random sampling design was used in each Health Zone, whereby 25 villages (clusters) and 30 households per cluster were sampled. Consenting eligible participants (children aged 1–9 years and adults aged ≥15 years) were examined for trachoma by GTMP-certified graders; households were assessed for access to WASH.

Results: A total of 32,758 households were surveyed, and 141,853 participants (98.2% of those enumerated) were examined for trachoma. Health Zone-level TF prevalence in 1–9-year-olds ranged from 1.9–41.6%. Among people aged ≥15 years, trichiasis prevalences ranged from 0.02–5.1% (95% CI 3.3–6.8). TF prevalence in 1–9-year-olds was ≥5% in 30 Health Zones, while trichiasis prevalence was ≥0.2% in 37 Health Zones.

Conclusion: Trachoma is a public health problem in 39 of 46 Health Zones surveyed. To meet elimination targets, 37 Health Zones require expanded trichiasis surgery services while 30 health zones require antibiotics, facial cleanliness and environmental improvement interventions. Survey data suggest that trachoma is widespread: further surveys are warranted.

First evidence of lymphatic filariasis transmission interruption in Cameroon: Progress towards elimination

BACKGROUND

Lymphatic filariasis (LF) is among the 10 neglected tropical diseases targeted for control or elimination by 2020. For LF elimination, the World Health Organization (WHO) has proposed a comprehensive strategy including (i) interruption of LF transmission through large-scale annual treatment (or mass drug administration (MDA)) of all eligible individuals in endemic areas, and (ii) alleviation of LF-associated suffering through morbidity management and disability prevention. In Cameroon, once-yearly mass administration of ivermectin and albendazole has been implemented since 2008. The aim of this study was to assess progress towards the elimination goal, looking specifically at the impact of six rounds of MDA on LF transmission in northern Cameroon.

METHODOLOGY

The study was conducted in the North and Far North Regions of Cameroon. Five health districts that successfully completed six rounds of MDA (defined as achieving a treatment coverage ≥ 65% each year) and reported no positive results for Wuchereria bancrofti microfilariaemia during routine surveys following the fifth MDA were grouped into three evaluation units (EU) according to WHO criteria. LF transmission was assessed through a community-based transmission assessment survey (TAS) using an immunochromatographic test (ICT) for the detection of circulating filarial antigen (CFA) in children aged 5-8 years old.

PRINCIPAL FINDINGS

A total of 5292 children (male/female ratio 1.04) aged 5-8 years old were examined in 97 communities. Positive CFA results were observed in 2, 8 and 11 cases, with a CFA prevalence of 0.13% (95% CI: 0.04-0.46) in EU#1, 0.57% (95% CI: 0.32-1.02) in EU#2, and 0.45% (95% CI: 0.23-0.89) in EU#3.

CONCLUSION/SIGNIFICANCE

The positive CFA cases were below WHO defined critical cut-off thresholds for stopping treatment and suggest that transmission can no longer be sustained. Post-MDA surveillance activities should be organized to evaluate whether recrudescence can occur.

Prevalence of Trachoma in Northern Benin: Results from 11 Population-Based Prevalence Surveys Covering 26 Districts

Aims

We sought to evaluate trachoma prevalence in all suspected-endemic areas of Benin.

Methods

We conducted population-based surveys covering 26 districts grouped into 11 evaluation units (EUs), using a two-stage, systematic and random, cluster sampling design powered at EU level. In each EU, 23 villages were systematically selected with population proportional to size; 30 households were selected from each village using compact segment sampling. In selected households, we examined all consenting residents aged one year or above for trichiasis, trachomatous inflammation – follicular (TF), and trachomatous inflammation – intense. We calculated the EU-level backlog of trichiasis and delineated the ophthalmic workforce in each EU using local interviews and telephone surveys.

Results

At EU-level, the TF prevalence in 1–9-year-olds ranged from 1.9 to 24.0%, with four EUs (incorporating eight districts) demonstrating prevalences ≥5%. The prevalence of trichiasis in adults aged 15+ years ranged from 0.1 to 1.9%. In nine EUs (incorporating 19 districts), the trichiasis prevalence in adults was ≥0.2%. An estimated 11,457 people have trichiasis in an area served by eight ophthalmic clinical officers.

Conclusion

In northern Benin, over 8000 people need surgery or other interventions for trichiasis to reach the trichiasis elimination threshold prevalence in each EU, and just over one million people need a combination of antibiotics, facial cleanliness and environmental improvement for the purposes of trachoma’s elimination as a public health problem. The current distribution of ophthalmic clinical officers does not match surgical needs.

Building a global schistosomiasis alliance: an opportunity to join forces to fight inequality and rural poverty

Schistosomiasis, one of the 17 neglected tropical diseases listed by the World Health Organization, presents a substantial public health and economic burden. Of the 261 million people requiring preventive chemotherapy for schistosomiasis in 2013, 92% of them lived in sub-Saharan Africa and only 12.7% received preventive chemotherapy. Moreover, in 2010, the WHO reported that schistosomiasis mortality could be as high as 280 000 per year in Africa alone.In May 2012 delegates to the sixty-fifth World Health Assembly adopted resolution WHA65.21 that called for the elimination of schistosomiasis, and foresees the regular treatment of at least 75% of school age children in at-risk areas. The resolution urged member states to intensify schistosomiasis control programmes and to initiate elimination campaigns where possible.Despite this, in June 2015, schistosomiasis was indicated to have the lowest level of preventive chemotherapy implementation in the spectrum of neglected tropical diseases. It was also highlighted as the disease most lacking in progress. This is perhaps unsurprising, given that it was also the only NTD with access to drug donations but without a coalition of stakeholders that collaborates to boost commitment and implementation.As a consequence, and to ensure that the WHO NTDs Roadmap Targets of 2012 and World Health Assembly Resolution WHA65.21 are met, the Global Schistosomiasis Alliance (GSA) has been set up. Diverse and representative, the GSA aims to be a partnership of endemic countries, academic and research institutions, international development agencies and foundations, international organizations, non-governmental development organizations, private sector companies and advocacy and resource mobilisation partners. Ultimately, the GSA calls for a partnership to work for the benefit of endemic countries by addressing health inequity and rural poverty.

Initiating NTD programs targeting schistosomiasis and soil-transmitted helminthiasis in two provinces of the Democratic Republic of the Congo: Establishment of baseline prevalence for mass drug administration

BACKGROUND

Schistosomiasis (SCH) and soil-transmitted helminthiasis (STH) are widely distributed in the Democratic Republic of the Congo (DRC) and constitute a serious public health problem. As recommended by the World Health Organization (WHO), before launching mass chemotherapy to control these diseases, parasitological surveys were conducted in sentinel sites in six health zones (HZs) in Bandundu and Maniema provinces. Baseline prevalence and intensity of infection for SCH and STH were determined to establish the appropriate treatment plan using Praziquantel (PZQ) and Albendazole (ALB).

METHODS

Parasitological surveys were conducted from April to May 2015 in twenty-six selected sampling units (schools) for baseline mapping in six HZs: Fifty school children (25 females and 25 males) aged 9-15 years were randomly selected per sampling unit. A total of 1300 samples (urine and stool) were examined using haematuria dipsticks, parasite-egg filtration and the point-of-care Circulating Cathodic Antigen (POC-CCA) assay for urine samples and the Kato-Katz technique for stool specimens.

RESULTS

Three species of schistosomes (S. mansoni, S. haematobium and S. intercalatum) and three groups of STH (hookworm, Ascaris and Trichuris) were detected at variable prevalence and intensity among the schools, the HZs and the provinces. In Bandundu, no SCH was detected by either Kato-Katz or the POC-CCA technique, despite a high prevalence of STH with 68% and 80% at Kiri and Pendjua HZs, respectively. In Maniema, intestinal schistosomiasis was detected by both Kato-Katz and POC-CCA with an average prevalence by Kato-Katz of 32.8% and by POC-CCA of 42.1%. Comparative studies confirmed the greater sensitivity (and operational feasibility) of the POC-CCA test on urine compared to Kato-Katz examination of stool for diagnosing intestinal schistosomiasis even in areas of comparatively light infections. STH was widely distributed and present in all HZs with a mean prevalence (95% CI) of 59.62% (46.00-65.00%). The prevalence of hookworm, roundworm and whipworm were 51.62% (32.40%-71.50%), 15.77% (0.50%-39.60%) and 13.46 (0.50%-33.20%), respectively.

CONCLUSION

This study provided the evidence base for implementing programs targeting SCH and STH in these Health Zones. Observations also reinforce the operational value and feasibility of the POC-CCA test to detect S. mansoni and, for the first time, S. intercalatum infections in a routine NTD program setting.

Evaluation of Lymphatic Filariasis and Onchocerciasis in Three Senegalese Districts Treated for Onchocerciasis with Ivermectin

In Africa, onchocerciasis and lymphatic filariasis (LF) are co-endemic in many areas. Current efforts to eliminate both diseases are through ivermectin-based mass drug administration (MDA). Years of ivermectin distribution for onchocerciasis may have interrupted LF transmission in certain areas. The Kédougou region, Senegal, is co-endemic for LF and onchocerciasis. Though MDA for onchocerciasis started in 1988, in 2014 albendazole had not yet been added for LF. The objective of this study was to assess in an integrated manner the LF and onchocerciasis status in the three districts of the Kédougou region after ≥10 years of ivermectin-based MDA. The study employed an African Programme for Onchocerciasis Control (APOC) onchocerciasis-related methodology. In the three districts, 14 villages close to three rivers that have Simulium damnosum breeding sites were surveyed. Convenience sampling of residents ≥5 years old was performed. Assessment for LF antigenemia by immunochromatographic testing (ICT) was added to skin snip microscopy for onchocerciasis. Participants were also tested for antibodies against Wb123 (LF) and Ov16 (onchocerciasis) antigens. In two districts, no participants were ICT or skin snip positive. In the third district, 3.5% were ICT positive and 0.7% were skin snip positive. In all the three districts, Wb123 prevalence was 0.6%. Overall, Ov16 prevalence was 6.9%. Ov16 prevalence among children 5-9 years old in the study was 2.5%. LF antigenemia prevalence was still above treatment threshold in one district despite ≥10 years of ivermectin-based MDA. The presence of Ov16 positive children suggested recent transmission of Onchocerca volvulus. This study showed the feasibility of integrated evaluation of onchocerciasis and LF but development of integrated robust methods for assessing transmission of both LF and onchocerciasis are needed to determine where MDA can be stopped safely in co-endemic areas.

Integrated implementation of programs targeting neglected tropical diseases through preventive chemotherapy: identifying best practices to roll out programs at national scale

In 2006 the U.S. Agency for International Development (USAID) established the Neglected Tropical Disease (NTD) Control Program to support national governments in developing successful, cost-efficient NTD programs that integrate disease-specific programs into coordinated national initiatives, in accord with the World Health Organization recommendations. A 3-stage "roll-out package" has been developed for effectively integrating and scaling up such programs to full-national scale. Stage-1 lays the groundwork-identifying NTD leadership within the Ministry of Health, conducting a national Situation Analysis, formulating a multiyear Plan of Action, and undertaking a funding gap analysis. Stage-2 focuses on scaling up the integrated NTD program-convening national stakeholder meetings, developing annual work plans, carrying out disease mapping, and establishing monitoring and evaluation activities. Stage-3 aims at ensuring effective management-identifying clear roles and responsibilities for partners, and creating a central coordinating mechanism. Assessment and reassessment of these complex NTD programs that target literally billions of people are essential to establish "best practice" strategies for long-term public health success.

Integrated implementation of programs targeting neglected tropical diseases through preventive chemotherapy: identifying best practices to roll out programs at national scale

In 2006 the U.S. Agency for International Development (USAID) established the Neglected Tropical Disease (NTD) Control Program to support national governments in developing successful, cost-efficient NTD programs that integrate disease-specific programs into coordinated national initiatives, in accord with the World Health Organization recommendations. A 3-stage "roll-out package" has been developed for effectively integrating and scaling up such programs to full-national scale. Stage-1 lays the groundwork-identifying NTD leadership within the Ministry of Health, conducting a national Situation Analysis, formulating a multiyear Plan of Action, and undertaking a funding gap analysis. Stage-2 focuses on scaling up the integrated NTD program-convening national stakeholder meetings, developing annual work plans, carrying out disease mapping, and establishing monitoring and evaluation activities. Stage-3 aims at ensuring effective management-identifying clear roles and responsibilities for partners, and creating a central coordinating mechanism. Assessment and reassessment of these complex NTD programs that target literally billions of people are essential to establish "best practice" strategies for long-term public health success.

Integrated implementation of programs targeting neglected tropical diseases through preventive chemotherapy: proving the feasibility at national scale

In 2006, the United States Agency for International Development established the Neglected Tropical Disease (NTD) Control Program to facilitate integration of national programs targeting elimination or control of lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiasis and blinding trachoma. By the end of year 3, 12 countries were supported by this program that focused first on disease mapping where needed, and then on initiating or expanding disease-specific programs in a coordinated/integrated fashion. The number of persons reached each year increased progressively, with a cumulative total during the first three years of 98 million persons receiving 222 million treatments with donated drugs valued at more than $1.4 billion. Geographic coverage increased substantially for all these infections, and the program has supported training of more than 220,000 persons to implement the programs. This current experience of the NTD Control Program demonstrates clearly that an integrated approach to control or eliminate these five neglected diseases can be effective at full national scale.

Mapping, monitoring, and surveillance of neglected tropical diseases: towards a policy framework

As national programmes respond to the new opportunities presented for scaling up preventive chemotherapy programmes for the coadministration of drugs to target lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiasis, and trachoma, possible synergies between existing disease-specific policies and protocols need to be examined. In this report we compare present policies for mapping, monitoring, and surveillance for these diseases, drawing attention to both the challenges and opportunities for integration. Although full integration of all elements of mapping, monitoring, and surveillance strategies might not be feasible for the diseases targeted through the preventive chemotherapy approach, there are opportunities for integration, and we present examples of integrated strategies. Finally, if advantage is to be taken of scaled up interventions to address neglected tropical diseases, efforts to develop rapid, inexpensive, and easy-to-use methods, whether disease-specific or integrated, should be increased. We present a framework for development of an integrated monitoring and evaluation system that combines both integrated and disease-specific strategies.

Multivariate analyses on morphological traits of goats in Burkina Faso

Abstract. A total of 10,147 female goats from Burkina Faso were scored for 7 body measures and 12 qualitative traits. Sampling included the three main environmental areas and goat breeds of Burkina Faso: the Sahel area (Sahelian goat), the Sudan-Sahel area (Mossi goat) and the Sudan area (Djallonké goat). Overall, the Sahelian goat had the highest values for the all the analysed body measures. Differences between the Sudan and the Sudan-Sahel goat were little. The Burkina Faso goat is mainly spotted (61.92 %) with horns type “Spanish Ibex” (84.05 %), frequent absence of beard (75.33 %) and wattles (70.92 %) and poorly developed udder (73.72 %). The Sahelian population included most individuals with dropping (95.60 %) and curled (73.62 %) ears, whilst most Sudan-Sahel individuals had horizontal ears (73.14 %) and most Sudan individuals had vertical ears (97.88 %). The largest Mahalanobis distance was found between the Sahelian and Sudan areas (7.50) whilst the Sudan and the Sudan-Sahel populations were poorly differentiated (1.15). Discriminant analysis showed that most Sahel and Sudan-Sahel individuals were classified into their source population (79.29 % and 82.69 %) whilst the Sudan individuals (93.40 %) were classified as Sudan-Sahel individuals. Both the canonical and the correspondence analyses showed that the Sahelian and Sudan individuals tended to cluster separately whilst the Sudan-Sahel individuals showed an intermediate distribution but clearly biased toward the Sudan individuals. The Sudan-Sahel (Mossi) population can be considered a result from the genetic contact between Sahelians and Sudan goats.

Post-translational processing of surfactant protein-C proprotein: targeting motifs in the NH(2)-terminal flanking domain are cleaved in late compartments

Rat surfactant protein (SP)-C is a 3.7-kD hydrophobic lung-specific protein generated from proteolytic processing of a 21-kD propeptide (SP-C(21)). We have demonstrated that initial post-translational processing of SP-C(21) involves two cleavages of the COOH-terminus (Beers and colleagues, J. Biol. Chem. 1994;269:20,318--20,328). The goal of the current study was to define processing and function of the NH(2)-terminal flanking domain. Epitope-specific antisera directed against spatially distinct regions of the NH(2) terminus, NPROSP-C(2-9) (epitope = D(2)-L(9)) and NPROSP-C(11-23) (= E(11)-Q(23)) were produced. By Western blotting, both antisera identified SP-C(21) in microsomes. A 6-kD form (SP-C(6)), enriched in lamellar bodies (LBs), was detected only by NPROSP-C(11-23) and not extractable with NaCO(3) treatment. Immunogold staining of ultrathin lung sections with NPROSP-C(11-23) identified proSP-C in both multivesicular bodies (mvb) and LBs whereas NPROSP-C(2-9) labeled only mvb. (35)S-pulse chase analysis demonstrated synthesis of SP-C(21) and three intermediate forms (SP-C(16), SP-C(7), and SP-C(6)). Complete processing involved four separate cleavages with a precursor- product relationship between the low molecular weight forms SP-C(7) and SP-C(6). Fluorescence microscopy of A549 cells expressing fusion proteins of enhanced green fluorescent protein (EGFP) and proSP-C NH(2)-terminal deletion mutants showed targeting of EGFP/SP-C(1-194) and EGFP/SP-C(10-194) to early endosomal antigen-1-negative, CD-63-positive cytoplasmic vesicles whereas EGFP/SP-C(19-194), EGFP/SP-C(Delta 10-18), and EGFP/SP-C(24-194) were restricted to the endoplasmic reticulum (ER). We conclude that synthetic processing includes a previously unrecognized cleavage of the proximal NH(2) terminus (M(1)-L(9)), which occurs after removal of COOH-flanking domains (H(59)-I(194)) but before packaging in LBs, and that the region M(10)-T(18) is required for targeting of proSP-C to post-ER vesicular compartments in the biosynthetic pathway.

[HIV infection at the work-place: beliefs and attitudes compliance to ethical standards]

The aims of this study undertaken from May 2000 to August 2000, were to appreciate workers feelings about ethical questions arisen in workplaces. Three industries were randomly chosen among a total of seven which benefited from HIV preventive policy. Two hundred workers randomly chosen by a multistage sampling method, were interviewed by an occupational physician on their beliefs and attitudes about HIV infection. Mean age was 41 years, 82.5% were male and 75.5% did benefit from high school education. 76% of workers had a good level of knowledge about transmission and prevention methods about HIV. 76.5% were willing to take care of people infected. 73% believed that infected persons must continue their job in the workplace. For 63.5% infected patients should receive more care than the other sick persons no matter what disease is concerned. These positive attitudes are highly correlated with level of knowledge (p < 0.001). In contrary 73.5% did state that pathient status should be revealed. These findings are globally compliant with ethical issues except for confidentiality questions. They invite to enforce preventive measures in workplaces.