Malnutrition and intestinal helminth infections in schoolchildren from Dibanda, Cameroon.

Intestinal helminth infections and malnutrition constitute a major health burden in developing countries, with infants and children being the most vulnerable groups. The extent of the burden of intestinal helminth infections and malnutrition was investigated in a cross-sectional study involving 265 children aged between 4 and 14 years residing in Dibanda, a semi-rural area located in Buea, South West Region, Cameroon. The prevalence of intestinal helminth infections was determined microscopically after faecal samples were prepared by the formol-ether sedimentation concentration technique of stool analysis. Nutritional status was determined using age and the anthropometric parameters of weight and height. Standard deviation (SD) or Z scores of height-for-age (HAZ), weight-for-age (WAZ) and weight-for-height (WHZ) were computed based on the World Health Organization 2006 growth reference curves. Anaemia was assessed by packed cell volume (PCV). The prevalence of intestinal helminth infection in the study population was 47.2% (125/265). All infections were of low intensity, with Ascaris recording the highest geometric mean egg count (GMEC) ± SEM of 363.51 ± 60.35 (egg count range: 76-3000 eggs/gram of stool). Overall, 42.3% of children had PCV < 31%. Also, 47.2% of those with intestinal helminth infections also had PCV < 31%. The prevalence of malnutrition was 30.2% (80/265). Of 80 malnourished children, 5.3% were wasted ( < - 2SD weight-for-height Z-score), 7.2% underweight ( < - 2SD weight-for-age Z score) and 24.2% stunted ( < - 2SD height-for-age Z score). The mean values of all the anthropometric indices were lower in helminth-infected children. Findings from this study are strongly suggestive that intestinal helminth infections and malnutrition exist in children residing in Dibanda and constitute a major health problem that needs to be addressed immediately to reduce morbidity and mortality.

The epidemiology of soil-transmitted helminth and protozoan infections in south-west Cameroon.

A cross-sectional study of the prevalence, intensity and effects of soil-transmitted helminth and protozoan infections was undertaken among patients at the Buea Hospital Annex located in Buea sub-division of Cameroon. Stool samples from 356 subjects (174 males and 182 females) were collected and processed using standard concentration methods. Our results showed that 31.0% of subjects were infected with intestinal helminths and the prevalence was higher in females (32.4%) than in males (30.5%). A significantly higher prevalence was observed in rural (47.2%) than in urban areas (21.0%); significance < 0.1%. Prevalence was highest among those aged between 6 and 12 years (41.4%). The total prevalence of intestinal helminth infections were 19.3% for Ascaris lumbricoides, 14.0% for hookworm and 11.8% for Trichuris trichiura. The intensity of infection was unevenly distributed, with very heavy loads concentrated in a few individuals. Data also showed that 28.1% (100/356) of the subjects were infected with protozoans. Females showed a higher prevalence (28.6%; 52/182) than males (20.7%; 36/174). Also, there was a significantly higher prevalence in rural (34.0%; 49/144) than urban areas (18.4%; 39/212); significance < 0.1%. The age group 6-12 years again had a higher prevalence (37.1%; 26/70). The total prevalence of intestinal protozoans was: Entamoeba histolytica (24.4%), Entamoeba coli (11.2%) and Giardia lamblia (0.6%). These relatively heavy prevalences in patients may be reduced by appropriate medication and maintaining strict personal hygiene. Health education, clean water supply, good sewage management and a congenial environment will all help to minimize infection.

Parasites of sheep and goats and their prevalence in Bokova, a rural area of Buea Sub Division, Cameroon.

Small ruminant production in the South West Province of Cameroon is practised mostly by subsistence farmers in the rural areas on natural grass pastures which grow once the primary forest has been cleared. Investigations revealed certain endo- and ectoparasites that were abundant and caused problems on the pastures to both animals and farmers. Haemonchus contortus was the most prevalent species with a prevalence of 94.23%. The highest mean monthly intensity was obtained in August and there was a significant difference (P<0.05) from the other months. Strongyle infections were prevalent in 93.18% of the animals examined. In the flock there was a prevalence of 96.25% in sheep as opposed to 86% in goats. The prevalence in the subsistence system was 95.4%. Mean monthly egg counts and prevalence of flukes was highest in December, 187.84 (29.73%). The overall prevalence of flukes was 73.88% with an overall mean intensity of 22 flukes per animal. The most abundant tick species was Haemaphysilis leachi. Genital distribution of ticks was significantly higher (P<0.05) in females than males. In the males they were more concentrated around the scrotum.

Molluscicidal activity of some Cameroonian plants on Bulinus species.

OBJECTIVE: To evaluate some locally available plants for their molluscicidal activity on Bulinus camerunensis and B. truncatus (slender form). DESIGN: Experimental studies. SETTING: Ndongo stream near the University of Buea and the University of Buea Life Sciences Laboratory. SUBJECTS: Evaluation of molluscicidal activity on snails of Bulinus camerunensis and B. truncatus (slender form). MAIN OUTCOME MEASURES: Plant extracts with molluscicidal activity determined. Determination of LC50, LC90 and LC100 of the potent plant extracts. Application of the extracts on aquaria-reared snails. Semi-field application of extracts. RESULTS: A preliminary screening test using 10,000 ppm solution of the water extracts of thirteen plants revealed that 61.5% (8/13) of the plants investigated had molluscicidal properties, with snail mortality rates above 90%. Extracts of Nicotiana tabacum, Aframomum citratum, A. melegueta, Curcuma domestica and Solanum scabrum killed 100% of the snails after twenty four hours exposure. B. camerunensis was more susceptible to the water extracts than B. truncatus. The LC50, LC90 and LC100 of the different plant extracts against B. camerunensis were generally lower than those against B. truncatus. The concentrations that produced 50%, 90% and 100% snail mortalities were lower with the methanol extracts than with water extracts, indicating that the methanol extracts were more toxic. to the snails than the water extracts. Generally, the eggs were more susceptible to the extracts than the young and adult snails. Application of the water extracts at LC 100 on snails reared in aquaria and under semi-field conditions revealed that N. tabacum could kill up to 100% of the snails in aquaria and 61.25% under semi-field conditions. CONCLUSION: Eight plant species with molluscicidal activity were identified, among which Nicotiana tabacum, Aframomum citratum, A. melegueta, Solanum scabrum and Curcuma domestica presented the highest activity. B. camerunensis was more susceptible to all the plant extracts tested than B. truncatus, and the methanol extracts proved more toxic than the water extracts. Semi-field testing of potent extracts showed promise, with N. tabacum having the highest effects on the snails.

Serological changes in goats experimentally infected with Fasciola gigantica in Buea sub-division of S.W.P. Cameroon.

Based on the recent increase in the rearing of West African Dwarf (WAD) goats in this environment, a study of biochemical parameters was carried out in healthy and infected goats to obtain baseline data for monitoring the health and productive indices in breeding programmes for the goats. The results revealed variations in some of the parameters studied. The serum minerals potassium, chlorine and bicarbonate did not show any significant differences (P>0.05) between the infected and control groups of goats, but there was a significant difference (P<0.0001) in sodium, calcium and urea levels. For serum lipids cholesterol and triglyceride, there were significant (P<0.0001) differences between the infected and control group. This goes same for serum proteins, albumin and total proteins. However, serum enzymes, serum glutamic oxaloacetic transaminase (SGOT) and gamma glutamyl transferase (GGT) were not significantly different (P>0.05) between the infected and control groups. There was a significant difference (P<0.0001) in alkaline phosphatase (ALP) and serum glutamic pyruvic transaminase (SGPT) between the infected and control groups.

Malaria infection and its consequences in school children.

OBJECTIVES: To evaluate the prevalence and consequences of malaria infection in school children in the Muea area and its environment. DESIGN: A cross-sectional study. SETTING: Muea area, South West Cameroon. SUBJECTS: Two hundred and fourty six randomly selected school children aged three to sixteen years. MAIN OUTCOME MEASURES: Prevalence of malaria in the Muea area. Determination of parasitaemia. Measurement of haematocrit (PCV) values. Species identification. Consequences of malaria infection in terms of school days lost. RESULTS: Prevalence of malaria was 98% and highest prevalence rate (100%) and geometric mean parasite density (1520 parasites/microl of blood) occurred in the < or = 5 years age group. Prevalence of anaemia was generally low (10.8%) and there were no cases of severe anaemia (PCV < 20%). P. vivax-like parasites were detected for the first time in this area. Plasmodium falciparum was the predominant species (93%) followed by P. malariae (52%), P. ovale (42.7%) and P. vivax-like parasites (33.3%). Mixed infections also occurred. Fifty three out of 144 (36.8%) children lost a number of school days ranging from 0.5-14 days, with each child losing an average of 1.53 school days in a month. CONCLUSION: The prevalence of asymptomatic malaria in the Muea area is very high. P. vivax parasites were observed for the first time in the area, but this needs to be confirmed by molecular methods in future studies. Children lost school days as a consequence of malaria infection.

Antibody and circulating antigen profiles before and after chemotherapy in goats infected with Fasciola gigantica.

The profiles of antibody response and circulating antigen levels in goats infected with Fasciola gigantica were studied by enzyme-linked immunoelectrotransfer blot (EITB) and enzyme-linked immunosorbent assay (ELISA). In the antibody assay, sera from goats experimentally infected with F. gigantica were reacted with whole worm antigen of the worm before and after chemotherapy with oxyclozanide. In ELISA, there was a significant increase in antibody level 2 weeks after infection. After chemotherapy, there was a gradual decrease in antibody within 3 weeks followed by a rapid decline by the 4th week after treatment. By EITB, the infected goat sera recognized three polypeptides in the range of 42-80 kDa as early as 2 weeks after infection. Recognition of the complete components of F. gigantica antigen repertoire occurred as early as the 4th week after infection. By the 8th week after chemotherapy, distinct polypeptide band recognition was no longer possible. Comparative immunoblotting with goat anti-Paramphistomum, anti-Dicrocoelium and anti-Fasciola sera revealed that the 14 kDa, 17 kDa, 21 kDa, 28 kDa and 30 kDa proteins are specific to F. gigantica. In the antigen assay, circulating antigen was detectable by the direct ELISA method one week after infection and negative absorbance values were observed 4 weeks after chemotherapy.

Detection of circulating antigen in sera of Fasciola gigantica-infected cattle with antibodies reactive with a Fasciola-specific 88-kDa antigen.

Antibodies against a specific 88-kDa antigen of Fasciola gigantica were used for the detection of circulating antigen in the sera of cattle with experimental and natural infections of F. gigantica by a double antibody ELISA. Circulating antigen was detectable as early as the second and third weeks after infection and positive absorbance values were obtained for the entire duration of infection. Absorbance values decreased below the cutoff point 3 weeks after chemotherapy with oxyclozanide. This immunoassay also greatly enhanced the specificity of immunodiagnosis of fasciolosis in naturally infected cattle. The test system has excellent potential for the accurate diagnosis of ruminant fasciolosis.

Malaria and intestinal helminthiasis in school children of Kumba Urban Area, Cameroon.

BACKGROUND: Malaria and intestinal helminthiasis are parasitic diseases causing high morbidity and mortality in most tropical parts of the world, where climatic conditions and sanitation practices favour their prevalence. These infections do co-exist and have different effects on infected individuals. OBJECTIVES: To assess the level of endemicity of malaria and helminth infections in school children of the Kumba Urban Area of Cameroon, and to determine how these infections relate to each other. DESIGN: Cross sectional study. SETTING: Four primary schools in the Kumba urban area. SUBJECTS: Two hundred and forty three randomly selected pupils aged four and fifteen years of both sexes. RESULTS: All two hundred and forty three pupils had malaria parasites in their blood. The geometric mean parasite load was 1282 parasites per microl of blood. Only 17 pupils were anaemic (PCV<30%), The helminth infections showed a 38.3% prevalence, with a geometric mean parasite load of 687 eggs per gram of faeces. Co-infections were recorded in 38.3% of the pupils. There was no significant correlation between the helminth and malaria parasite densities (r=0.04, P=0.7337). CONCLUSION: Both malaria and helminth parasites do co-exist without clinical symptoms of infection in school children of the Kumbi Urban Area.

Climate change and altitudinal structuring of malaria vectors in south-western Cameroon: their relation to malaria transmission.

An entomological survey was conducted in Cameroon between October 2004 and September 2005, in nine localities targeted for malaria vector control based on adult productivity and variability. Mosquitoes were collected by human-landing catches (HLCs) and pyrethrum spray catches. A total of 12 500 anophelines were collected and dissected: Anopheles gambiae s.l. (56.86%), An. funestus s.l. (32.57%), An. hancocki (9.38%), and An. nili (1.18%). Applying PCR revealed that specimens of the An. funestus group were An. funestus s.s. and An. gambiae complex were mostly An. melas and An. gambiae s.s. of the M and S molecular forms with the M forms being the most predominant. The natural distribution patterns of Anopheles species were largely determined by altitude with some species having unique environmental tolerance limits. A human blood index (HBI) of 99.05% was recorded. Mean probability of daily survival of the malaria vectors was 0.92, with annual mean life expectancy of 21.9 days and the expectation of infective life was long with a mean of 7.4 days. The high survival rates suggest a high vector potential for the species. This information enhances the development of a more focused and informed vector control intervention.