Prevalence, knowledge and practices towards tuberculosis prevention in the Bamenda III sub-division, Cameroon.

BACKGROUND: Tuberculosis (TB) is a major public health problem in developing countries. WHO estimates the prevalence in Cameroon at 17.7% (179/100,000). OBJECTIVES: To determine the prevalence of TB and assess the level of knowledge and practices towards TB prevention among residents of the Bamenda III sub-division of North West Cameroon. METHODS: A retrospective study design was used to generate data on the prevalence of TB from 2016 to 2020 while a descriptive cross-sectional study design was used to generate information on the level of knowledge and practices towards TB prevention. RESULTS: Out of 4950 presumptive cases of TB (all forms), 469 (9.5%) were placed on TB treatment. The highest prevalence was in 2016 (2.9%) and the lowest in 2019 (1.8%). The majority (65.3%, n = 186) of respondents had adequate knowledge of TB while 143 (57.1%) demonstrated adequate practices in TB prevention. There was a positive correlation between knowledge and practice towards TB prevention (ɼ2 = 29.47, p = 0.001). CONCLUSION: The prevalence of TB (2016-2020) was 9.5%. About one-third of respondents had inadequate knowledge and practices in TB prevention. Sensitization and intensified case finding in favor of TB in this community is encouraged.

Anti-Onchocercal Properties of Extracts of Scoparia dulcis and Cylicodiscus gabunensis.

Introduction: The elimination of onchocerciasis is hampered by the absence of suitable drugs that are effective against adult filariae. This study is aimed at assessing the anti-onchocercal effects of extracts of Scoparia dulcis and Cylicodiscus gabunensis that could serve as drug leads against onchocerciasis. Methods: Different parts of the plants (Scoparia dulcis and Cylicodiscus gabunensis) were extracted with hexane, methylene chloride, and methanol. The extracts were tested in vitro against the bovine model parasite, Onchocerca ochengi. Adult female worm viability was determined biochemically by MTT/formazan colorimetry, while the adult male and microfilariae viability were determined by microscopy based on % inhibition of worm motility score. Cytotoxicity and acute toxicity of active extracts were tested on monkey kidney epithelial cells (LLC-MK2) and Balb/C mice, respectively. Results: The hexane extract of Scoparia dulcis recorded the highest activity, with IC50s of 50.78 µg/ml on both adult male and female worms and 3.91 µg/ml on microfilariae. For Cylicodiscus gabunensis extract, the highest activity was seen with the methylene chloride extract, with IC50s of 50.78 µg/ml, 62.50 µg/ml, and 16.28 µg/ml on, respectively, adult male, female, and microfilariae. The 50% cytotoxic concentration on the LLC-MK2 cells was 31.25 µg/ml for the most active extracts. No acute toxicity was recorded for the extracts. Phytochemical analysis of the extracts revealed the presence of alkaloids, flavonoids, sterols, saponins, phenols, and glycosides. Conclusion: This study validates the traditional use of these plants in treating onchocerciasis and suggests S. dulcis and C. gabunensis as new potential sources for the isolation of anti-onchocerca lead compounds.

Knowledge, attitude and seropositivity of hepatitis B virus among blood donors in the Bamenda Regional Hospital Blood Bank, Cameroon.

INTRODUCTION: despite the existence of a preventive vaccine against hepatitis B viral (HBV) infection, approximately 250 million people are infected with the virus worldwide. This study aimed at evaluating the level of knowledge, attitude and seropositivity of the disease among apparently healthy, potential blood donors at the blood service of the Bamenda Regional Hospital Blood Bank. METHODS: a cross-sectional study was carried out from March to May 2019 among 250 blood donors. Following screening for hepatitis B surface antigen (HBsAg) using the one-step HBsAg test strip, information on the level of knowledge and attitude towards the infection was obtained using a self-administered questionnaire. The correlation analysis was done to assess relationships between selected factors and knowledge of hepatitis B, p-value of 0.05 was considered as statistical significance. RESULTS: the seropositivity of HBV was 6.4% (n = 16). Overall, 46.8% (n = 19) of the study participants had adequate knowledge while 76.3% (n = 31) had a positive attitude toward the disease. The highest seropositivity was observed in singles (7.1%; n = 13), primary school leavers (14.3%; n = 5), unskilled laborers (14.5%; n = 8) and replacement donors (9.33%; n = 7). The probability of being hepatitis B seropositive was higher in males, students (aOR: 8.8, 95% CI 0.7-96.1; p = 0.046) and those who had attained higher education (aOR: 3.2, 95% CI 0.8-12.7; p = 0.016). Independent factors responsible for higher odds of inadequate knowledge were being a male and attaining secondary education. On the contrary, students (aOR: 0.3, 95% CI 0.1-0.8; p = 0.012) and those with a history of blood donation (aOR: 0.5, 95% CI 0.2-0.9; p = 0.042) recorded lower odds of inadequate knowledge. CONCLUSION: the prevalence of hepatitis B among blood donors in this blood service is in the high intermediate category. Overall, the level of knowledge on this infection among these blood donors is average. These findings suggest that health education on HBV infection should be provided to the public as a major strategy to curb the infection.

Trends in serological markers of transfusion transmissible infections in blood donations at the Bamenda Hospital-based Blood Service, Cameroon.

OBJECTIVES: The rate and trend of transfusion transmissible infections (TTIs) in blood donations from 2012 to 2017 at the Bamenda Regional Hospital Blood Service (BRHBS), Cameroon was assessed. MATERIALS AND METHODS: A six-year retrospective study was conducted by reviewing the records of donors. Blood was screened for HIV, hepatitis B, hepatitis C and syphilis. Data was analyzed using IBM SPSS Statistics version 21. Differences in seropositivity rates for the four TTIs were analyzed using Chi2 test or Fisher's exact test where appropriate. Associations between sociodemographic characteristics and the TTIs markers were assessed using multiple logistic regression analysis. RESULTS: A total of 12,115 blood donations was included in the study and of these, the overall seropositivity rate of the four conventional TTIs markers was 10.5% (n=1,273). Of the seropositive cases, 23.8% (n=303) showed reactivity with at least two of the markers combined. When the markers were assessed individually, HBsAg recorded the highest seropositivity rate (4.7%), followed by anti-HIV and anti-syphilis (2.2%), and then by anti-HCV (1.7%). A significant decrease in the trend of the combined serological markers, HBsAg and anti-syphilis was observed over the years (P≤0.05). CONCLUSION: There is a decrease in seropositivity rates of TTIs markers in this blood service. Ongoing efforts toward the prevention of these infections is encouraged and should be intensified to improve blood safety.

Filaricidal activity of Daniellia oliveri and Psorospermum febrifugum extracts.

BACKGROUND: Drugs currently used for controlling onchocerciasis and lymphatic filariasis (LF) are mainly microfilaricidal, with minimal or no effect on the adult worms. For efficient management of these diseases, it is necessary to search for new drugs with macrofilaricidal activities that can be used singly or in combination with existing ones. Daniellia oliveri and Psorospermum febrifugum are two plants commonly used in the local management of these infections in Bambui, a township in the North West Region of Cameroon, but there is currently no documented scientific evidence to support their claimed anthelmintic efficacy and safety. The aim of this study was to provide evidence in support of the search for means to eliminate these diseases by screening extracts and chromatographic fractions isolated from these plants for efficacy against the parasitic roundworms Onchocerca ochengi and Brugia pahangi. METHODS: The viability of O. ochengi adult worms was assessed using the MTT/formazan assay. Fully confluent monkey kidney epithelial cells (LLC-MK2) served as the feeder layer for the O. ochengi microfilariae (mfs) assays. Viability of the mfs was assessed by microscopic examination for mean motility scoring (relative to the negative control) every 24 h post addition of an extract. The Worminator system was used to test the effects of the extracts on adult B. pahangi motility, and mean motility units were determined for each worm. Cytotoxicity of the active extracts on N27 cells was assessed using the MTS assay. RESULTS: Extracts from D. oliveri and P. febrifugum were effective against the adult roundworms O. ochengi and B. pahangi. Interestingly, extracts showing macrofilaricidal activities against O. ochengi also showed activity against O. ochengi mfs. The hexane stem bark extract of D. oliveri (DOBHEX) was more selective for adult O. ochengi than for mfs, with a half maximal and 100% inhibitory concentration (IC50 and IC100, respectively) against adult O. ochengi of 13.9 and 31.3 µg/ml, respectively. The in vitro cytotoxicity of all active extracts on N27 cells showed selective toxicity for parasites (selectivity index > 1). Bioassay-guided fractionation of the extracts yielded fractions with activity against adult B. pahangi, thus confirming the presence of bioactive principles in the plant extracts. CONCLUSIONS: Our study supports the use of D. oliveri and P. febrifugum in the traditional treatment of onchocerciasis and LF. The further purification of active extracts from these plants could yield lead compounds for filarial drug discovery and development.

Evaluation of corrective actions of feedback from clinicians on Clinical Laboratory Services at Bamenda Regional Hospital Laboratory, Cameroon.

BACKGROUND: Customers' satisfaction is imperative for success. Clinical laboratories continuously strive to attain very high levels of customer satisfaction to serve their clients and maintain accreditation. The concept of customer satisfaction has not yet been asserted in most clinical laboratories in Cameroon. OBJECTIVES: Our objectives were to assess the satisfaction of clinicians with the laboratory services at the Bamenda Regional Hospital Laboratory, identify important challenges, corrective actions implemented and changes in satisfaction. METHODS: This retrospective study reviewed secondary data from clinician satisfaction survey records from March 2017 and November 2017. Challenges and implemented corrective actions were identified for assessed statements of dissatisfaction (dissatisfaction rates ≥ 20%) on the March 2017 survey. Satisfaction rates in March 2017 and November 2017 were compared. RESULTS: High levels of dissatisfaction were observed for general satisfaction, waiting time, communication, duty consciousness, specimen collection and approach on the March 2017 survey. The main challenges identified were: lack of respect for the expected length of the waiting time, poor attitude, inadequate information, staff shortage and inadequate supervision. Statistically significant reductions in rates of dissatisfaction were observed for general satisfaction, waiting time, communication, response to emergencies, issuing of results, specimen collection, approach and duty consciousness. CONCLUSION: Waiting time is a major cause of clinician dissatisfaction with laboratory services. The identification of clinicians' challenges and the effective implementation of corrective actions contribute to improvements in clinician satisfaction.

Prevalence and antibiotic susceptibility pattern of bacteriuria among HIV-seropositive patients attending the Bamenda Regional Hospital, Cameroon.

BACKGROUND: HIV causes a decrease in CD4+ lymphocyte cells count, exposing the individual to infections (urinary tract infections). This study was carried out to determine the prevalence of bacteriuria and antimicrobial susceptibility pattern of bacteria isolates among HIV patients. METHODS: Clean catch mid-stream urine samples were collected from 135 HIV- seropositive patients, cultured on Cystein lactose electrolyte deficient (CLED) agar and incubated at 370C for 24 hours. The modified Kirby-Bauer's disc diffusion method was used to assess susceptibility to antimicrobial agents. RESULTS: The prevalence of bacteriuria was 67.4% (91/135). Staphylococcus aureus was the most predominant (42.9%) isolate, followed by Escherichia. coli (24.2%), then Coagulase negative Staphylococci (10.9%). The highest proportion of bacteria was isolated from patients having a CD4+ T-cell count of less than 300 cells/mm3 (39.6%). There was an association between the level of CD4+cell count and bacterial urinary tract infection (P= 0.001). Most sensitive drugs were gentamycin, vancomycin and amoxicillin-clavulanic acid while the drug with the greatest resistance was sulphamethoxazole-trimethoprim, with Enterococcus and Proteus showing 100% resistance to this drug. CONCLUSION: Bacteriuria and resistance to commonly used antibiotics is prevalent among HIV/AIDS patients attending the Bamenda Regional Hospital. Therapy based on antimicrobial susceptibility test is encouraged.

Evaluation of corrective actions of feedback from clinicians on Clinical Laboratory Services at Bamenda Regional Hospital Laboratory, Cameroon

Background: Customers' satisfaction is imperative for success. Clinical laboratories continuously strive to attain very high levels of customer satisfaction to serve their clients and maintain accreditation. The concept of customer satisfaction has not yet been asserted in most clinical laboratories in Cameroon. Objectives: Our objectives were to assess the satisfaction of clinicians with the laboratory services at the Bamenda Regional Hospital Laboratory, identify important challenges, corrective actions implemented and changes in satisfaction. Methods: This retrospective study reviewed secondary data from clinician satisfaction survey records from March 2017 and November 2017. Challenges and implemented corrective actions were identified for assessed statements of dissatisfaction (dissatisfaction rates ≥ 20%) on the March 2017 survey. Satisfaction rates in March 2017 and November 2017 were compared. Results: High levels of dissatisfaction were observed for general satisfaction, waiting time, communication, duty consciousness, specimen collection and approach on the March 2017 survey. The main challenges identified were: lack of respect for the expected length of the waiting time, poor attitude, inadequate information, staff shortage and inadequate supervision. Statistically significant reductions in rates of dissatisfaction were observed for general satisfaction, waiting time, communication, response to emergencies, issuing of results, specimen collection, approach and duty consciousness. Conclusion: Waiting time is a major cause of clinician dissatisfaction with laboratory services. The identification of clinicians' challenges and the effective implementation of corrective actions contribute to improvements in clinician satisfaction

Macro and microfilaricidal activities of extracts of Annona senegalensis and Milletia comosa against Onchocerca ochengi and Loa loa.

Despite the efforts employed for the control of onchocerciasis, the latter has remained a significant public health problem, due mainly to the lack of safe and effective adult worm drugs and/or microfilaricides that do not kill Loa loa microfilariae (mf). Serious adverse events have been encountered after administering ivermectin to some onchocerciasis patients coinfected with Loa loa. There is therefore, an urgent need for a macro and/or microfilaricidal drug which kills Onchocerca but not L. loa microfilariae. A total of 12 crude extracts from Milletia comosa and Annona senegalensis were prepared and screened in vitro against the bovine species of Onchocerca, O. ochengi, and L. loa mf from humans. Mf and male worm viabilities were determined by motility scoring using microscopy at 120 h of incubation with drug, while adult female worm viability and cytotoxicity were determined biochemically by MTT/formazan colorimetry after 120 h of incubation with drug. Out of the 12 extracts, all 6 from M. comosa and 4 from A. senegalensis were active against male, female and mf of O. ochengi. The hexane extract from M. comosa leaves (MCL hex) was the most active with IC50 values of 1.38, 0.86 and 17.74 µg/mL for O. ochengi adult males, adult female and the mf, respectively. About 58% of the extracts were more active against O. ochengi than L. loa mf. These results demonstrate that these extracts contain active principles that kill Onchocerca parasite and to a lesser extent L. loa, and suggest that they can be fractionated for isolation of lead molecules for the safe treatment of onchocerciasis.

Brevipedicelones D and E, Two C-O-C Flavonoid Dimmers from the Leaves of Garcinia brevipedicellata and Anti-onchocercal Activity.

A novel isoflavone-chromone flavonoid C-O-C dimmer, brevipedicelone D (1), along with one new C-O-C biflavonoid derivative, brevipedicelone E (2), were isolated from the ethyl acetate extract of the leaves of Garcinia brevipedicellata, a medicinal plant used in folk medicine in parts of Cameroon. Their structures were elucidated by extensive spectroscopic techniques, including 1D- and 2D- NMR, MS experiments, as well as comparing their spectral data with those of known analogues. Anti-onchocercal screening of 1 showed moderate inhibition of adult worm motility of Onchocerca ochengi by 60% at the highest concentration (20 µg/mL) and inhibited motility of both the juvenile worms of O. ochengi and Loa loa by 90% at this same concentration.

Filaricidal properties of Lantana camara and Tamarindus indica extracts, and Lantadene A from L. camara against Onchocerca ochengi and Loa loa.

BACKGROUND: Ivermectin is the only drug currently recommended for the treatment of onchocerciasis, the second leading infectious cause of blindness in the world. This drug kills only the first stage larvae-microfilariae (mf) of Onchocerca volvulus and is to be used cautiously in areas where Loa loa is prevalent because of severe adverse events observed with coinfected patients. METHODOLOGY/PRINCIPAL FINDINGS: This study investigated the anti-filarial activities of two Cameroonian medicinal plants, Lantana camara and Tamarindus indica locally used to treat onchocerciasis. Twelve (12) extracts were prepared and tested in vitro on the bovine model parasite, O. ochengi as well as L. loa mf. Both mf and adult male worm viabilities were assessed by motility scoring, while adult female worm viability was determined biochemically by standard MTT/formazan colorimetry. Cytotoxicity and acute toxicity were determined respectively, in monkey kidney epithelial cells and in BALB/c mice. Pure compounds were isolated by LC/MS using a bio-assay guided strategy. All the extracts showed 100% activity at 500 µg/mL against O. ochengi adult worms and mf. The highest activity against O. ochengi was observed with the hexane extract of L. camara leaves (LCLhex), with IC50 of 35.1 µg/mL for adult females and 3.8 µg/mL for the mf. Interestingly, this extract was more active against O. ochengi mf than L. loa mf. Further studies on the extracts led to the isolation of lantadene A from the methylene chloride extract of L. camara leaves, with IC50s of 7.85 µg/mL for adult males, 10.38 µg/mL for adult females, 10.84 µg/mL for O. ochengi mf and 20.13 µg/mL for L. loa mf. CONCLUSIONS/SIGNIFICANCE: We report for the first time the anti-onchocercal activities of these locally consumed medicinal plants and lantadene A, a potential lead for further development as an onchocerciasis cure.

Filaricidal activities on Onchocerca ochengi and Loa loa, toxicity and phytochemical screening of extracts of Tragia benthami and Piper umbellatum.

BACKGROUND: Onchocerciasis is the world's second leading infectious cause of blindness. Its control is currently hampered by the lack of a macrofilaricidal drug and by severe adverse events observed when the lone recommended microfilaricide, ivermectin is administered to individuals co-infected with Loa loa. Therefore, there is the need for a safe and effective macrofilaricidal drug that will be able to cure the infection and break transmission cycles, or at least, an alternative microfilaricide that does not kill L. loa microfilariae (mf). METHODS: Fourteen extracts from two medicinal plants, Tragia benthami and Piper umbellatum were screened in vitro against Onchocerca ochengi parasite and L. loa mf. Activities of extracts on male worms and microfilariae were assessed by motility reduction, while MTT/Formazan assay was used to assess biochemically the death of female worms. Cytotoxicity and acute toxicity of active extracts were tested on monkey kidney cells and Balb/c mice, respectively. RESULTS: At 500 µg/mL, all extracts showed 100 % activity on Onchocerca ochengi males and microfilariae, while 9 showed 100 % activity on female worms. The methylene chloride extract of Piper umbellatum leaves was the most active on adult male and female worms (IC50s: 16.63 µg/mL and 35.65 µg/mL, respectively). The three most active extracts on Onchocerca ochengi females were also highly active on Loa loa microfilariae, with IC50s of 35.12 - 13.9 µg/mL. Active extracts were generally more toxic to the worms than to cells and showed no acute toxicity to Balb/c mice. Phytochemical screening revealed the presence of saponins, steroids, tannins and flavanoids in the promising extracts. CONCLUSIONS: These results unfold potential sources of novel anti-Onchocerca lead compounds and validate the traditional use of the plants in onchocerciasis treatment.

Repurposing auranofin as a lead candidate for treatment of lymphatic filariasis and onchocerciasis.

Two major human diseases caused by filariid nematodes are onchocerciasis, or river blindness, and lymphatic filariasis, which can lead to elephantiasis. The drugs ivermectin, diethylcarbamazine (DEC), and albendazole are used in control programs for these diseases, but are mainly effective against the microfilarial stage and have minimal or no effect on adult worms. Adult Onchocerca volvulus and Brugia malayi worms (macrofilariae) can live for up to 15 years, reproducing and allowing the infection to persist in a population. Therefore, to support control or elimination of these two diseases, effective macrofilaricidal drugs are necessary, in addition to current drugs. In an effort to identify macrofilaricidal drugs, we screened an FDA-approved library with adult worms of Brugia spp. and Onchocerca ochengi, third-stage larvae (L3s) of Onchocerca volvulus, and the microfilariae of both O. ochengi and Loa loa. We found that auranofin, a gold-containing drug used for rheumatoid arthritis, was effective in vitro in killing both Brugia spp. and O. ochengi adult worms and in inhibiting the molting of L3s of O. volvulus with IC50 values in the low micromolar to nanomolar range. Auranofin had an approximately 43-fold higher IC50 against the microfilariae of L. loa compared with the IC50 for adult female O. ochengi, which may be beneficial if used in areas where Onchocerca and Brugia are co-endemic with L. loa, to prevent severe adverse reactions to the drug-induced death of L. loa microfilariae. Further testing indicated that auranofin is also effective in reducing Brugia adult worm burden in infected gerbils and that auranofin may be targeting the thioredoxin reductase in this nematode.

In vitro anti-Onchocerca ochengi activities of extracts and chromatographic fractions of Craterispermum laurinum and Morinda lucida.

BACKGROUND: Onchocerciasis caused by Onchocerca volvulus is the world's second leading infectious cause of blindness. There is currently no cure for the disease. Ivermectin, the current drug of choice is only microfilaricidal and suboptimal response to it is increasingly being reported. Thus, in contributing to the search for a cure, crude extracts and chromatographic fractions of Craterispermum laurinum and Morinda lucida were screened in vitro, against the bovine and most popular model of the parasite, Onchocerca ochengi. METHODS: Extracted parasites were cultured in RPMI-1640 based media for 05 days in the presence of control drugs, test drugs or drug diluents only. Microfilarial motility was scored using microscopy while adult worm viability was determined biochemically by MTT/formazan colorimetry. Cytotoxicity and acute toxicity of active fractions were tested on monkey kidney epithelial cells (LLCMK2) and in Balb/c mice, respectively. RESULTS: Out of the 18 extracts screened, the methanolic extracts of the leaves of both plants recorded the highest activities against both the microfilariae (IC100 of 125 µg/ml for both extracts) and adult worms (IC100 of 250 µg/ml and 500 µg/ml for M. lucida and C. laurinum respectively). The most active chromatographic fraction was obtained from M. lucida and had an IC50 of 7.8 µg/ml and 15.63 µg/ml on microfilariae and adult worms respectively, while the most active fraction from C. laurinum had an IC50 of 15.63 µg/ml and 46.8 µg/ml, respectively on microfilariae and adult worms. The 50% cytotoxic concentration (CC50s) on LLCMK2 cells ranged from 15.625 µg/ml to 125 µg/ml for the active fractions. No acute toxicity was recorded for the extracts from both plants. Phytochemical analysis of the most active fractions revealed the presence of sterols, alkaloids, triterpenes, saponins and flavonoids. CONCLUSIONS: This study validates the use of these plants by traditional health practitioners in managing the disease, and also suggests a new source for isolation of potential lead compounds against Onchocerca volvulus.

Anti-Onchocerca activity and phytochemical analysis of an essential oil from Cyperus articulatus L.

BACKGROUND: The lack of a safe and effective adult worm drug and the emergence of resistant animal parasite strains to the only recommended drug, the microfilaricide, ivermectin put many at risk of the devastating effects of the onchocerciasis. The present study was undertaken to investigate the acclaimed anti-Onchocerca activity of the roots/rhizomes of Cyperus articulatus in the traditional treatment of onchocerciasis in North Western Cameroon and to assess the plant as a new source of potential filaricidal lead compounds. METHODS: Crude extracts were prepared from the dried plant parts using hexane, methylene chloride and methanol. The antifilarial activity was evaluated in vitro on microfilariae (Mfs) and adult worms of the bovine derived Onchocerca ochengi, a close relative of Onchocerca volvulus. The viabilities of microfilariae and adult male worms were determined based on motility reduction, while for the adult female worms the viability was based on the standard MTT/formazan assay. Cytotoxicity of the active extract was assessed on monkey kidney epithelial cells in vitro and the selectivity indices (SI) were determined. Acute toxicity of the promising extract was investigated in mice. Chemical composition of the active extract was unraveled by GC/MS analysis. RESULTS: Only the hexane extract, an essential oil exhibited anti-Onchocerca activity. The oil killed both the microfilariae and adult worms of O. ochengi in a dose manner dependently, with IC50s of 23.4 µg/ml on the Mfs, 23.4 µg/ml on adult male worms and 31.25 µg/ml on the adult female worms. Selectivity indices were 4, 4, and 2.99 for Mfs, adult males and adult females, respectively. At a single limit dose of 2000 mg/kg body weight, none of 6 mice that received the essential oil by gavage died. GC/MS analysis revealed the presence of terpenoids, hydrocarbons and fatty acids or fatty acid derivatives as components of the oil. CONCLUSIONS: The essential oil from the roots/rhizomes of Cyperus articulatus is active against O. ochengi microfilariae and adult worms in vitro in a dose dependent manner, hence may provide a source of new anti-filarial compounds. The results also support the traditional use of C. articulatus in the treatment of human onchocerciasis.

A longitudinal study on anaemia in children with Plasmodium falciparum infection in the Mount Cameroon region: prevalence, risk factors and perceptions by caregivers.

BACKGROUND: In heavily endemic malaria areas, it is almost inevitable that malarial infection will be associated with anaemia, although malaria may not be the prime cause of it. Anaemia is a major public health problem in Cameroon. We hypothesized that, factors other than falciparum malaria account for anaemia in the study area. METHODS: A longitudinal study was conducted among 351 Plasmodium falciparum positive children to determine the prevalence, risk factors and the perception of anaemia by the caregivers in a semi-rural community. The investigative methods included the use of a structured questionnaire, clinical evaluation and laboratory investigations. RESULTS: At enrolment the overall prevalence of anaemia as assessed by Hb concentration (Hb < 11 g/dl) was 80.3% (282). Following treatment the prevalence of persistent anaemia was 6% and 46.2% of the children achieved haematological recovery by day 42. Exploratory multiple linear regression analysis showed the following; parasitaemia density (P < 0.01), enlarged spleen (P < 0.05), duration of fever > 2 days (P < 0.01), high white blood cell count (P < 0.001), sex (P < 0.05), iron status indicators (ferritin and transferrin) (P < 0.001), level of education of the caregiver (P < 0.05), management of onset of malaria by caregiver (P < 0.005) and wasting (P < 0.05) to be risk factors for anaemia in children with falciparum infection. Approximately 75.5% (265) of the caregivers had some knowledge about anaemia. CONCLUSION: The identified risk factors revealed the important contributors to the pathogenesis of anaemia in the Mount Cameroon region. Control efforts should therefore be directed towards proper health education emphasizing on proper health seeking behaviour and attitudes of the population.

Design, synthesis, and biological activities of closantel analogues: structural promiscuity and its impact on Onchocerca volvulus.

Onchocerciasis, or river blindness, is a neglected tropical disease that affects more than 37 million people worldwide, primarily in Africa and Central and South America. We have disclosed evidence that the larval-stage-specific chitinase, OvCHT1, may be a potential biological target for affecting nematode development. On the basis of screening efforts, closantel, a known anthelmintic drug, was discovered as a potent and highly specific OvCHT1 inhibitor. Originally, closantel's anthelmintic mode of action was believed to rely solely on its role as a proton ionophore; thus, the impact of each of its biological activities on O. volvulus L3 molting was investigated. Structure-activity relationship studies on an active closantel fragment are detailed, and remarkably, by use of a simple salicylanilide scaffold, compounds acting only as protonophores or chitinase inhibitors were identified. From these data, unexpected synergistic protonophore and chitinase inhibition activities have also been found to be critical for molting in O. volvulus L3 larvae.

Low anticoagulant heparin disrupts Plasmodium falciparum rosettes in fresh clinical isolates.

The binding of Plasmodium falciparum parasitized erythrocytes to uninfected erythrocytes (rosetting) is associated with severe malaria. The glycosaminoglycan heparan sulfate is an important receptor for rosetting. The related glycosaminoglycan heparin was previously used in treatment of severe malaria, although abandoned because of the occurrence of severe bleedings. Instead, low anticoagulant heparin (LAH) has been suggested for treatment. LAH has successfully been evaluated in safety studies and found to disrupt rosettes and cytoadherence in vitro and in vivo in animal models, but the effect of LAH on fresh parasite isolates has not been studied. Herein, we report that two different LAHs (DFX232 and Sevuparin) disrupt rosettes in the majority of fresh isolates from Cameroonian children with malaria. The rosette disruption effect was more pronounced in isolates from complicated cases than from mild cases. The data support LAH as adjunct therapy in severe malaria.

Integrated dataset of screening hits against multiple neglected disease pathogens.

New chemical entities are desperately needed that overcome the limitations of existing drugs for neglected diseases. Screening a diverse library of 10,000 drug-like compounds against 7 neglected disease pathogens resulted in an integrated dataset of 744 hits. We discuss the prioritization of these hits for each pathogen and the strong correlation observed between compounds active against more than two pathogens and mammalian cell toxicity. Our work suggests that the efficiency of early drug discovery for neglected diseases can be enhanced through a collaborative, multi-pathogen approach.