Impact of Physico-Chemical Factors of Contaminated Foci on the Survival of Geohelminths in Abua Communities, Niger Delta Nigeria

Physio-chemical analysis of 200 soil samples collected from contaminated foci was investigated in six communities of Abua, Niger Delta Nigeria. The Jackson’s method was used in the chemical analysis of contaminated soils while Cobb’s decanting and sieving method was used in the extraction of geohelminths. The  data showed that temperature, pH, Calcium (Ca2+), magnesium (mg2+), potassium (k+) ions and electrical conductivity had much effect on the survival of  eggs and larval development of geohelminths. It was also observed that the nature of the soil in the study communities was clay-loam and sandy-loamy. The continuous deposition of human faeces in these contaminated foci should be discouraged. This can be achieved by the construction of toilet facilities of whatever description in the study  area by the government. @JASEMJ. Appl. Sci. Environ. Manage. December, 2010, Vol. 14 (4) 117 - 12

Bio-survey of Plankton as indicators of water quality for recreational activities in Calabar River, Nigeria

With the increasing recognition of Calabar as a global tourist destination, the suitability of Calabar River for recreational activities by tourists was investigated. The aim was to use phytoplankton and zooplankton characteristics to assess the water quality of the Calabar River. Phytoplankton and zooplankton samples were collected from four stations along the river and carried in plastic containers at 4oC to the laboratory for taxonomic and diversity index analyses. Water samples were also collected from the sampling stations for physico-chemicalanalysis. In total, 331 phytoplankton individuals were identified from sixty-six species in sixty genera and six taxonomic groups. The most abundant taxon was Bacillariophyceae 212 (64.05%), followed by Cyanophyceae 42 (12.69%), Chlorophyceae 40 (12.08%); Dinophyceae 16 (4.83%); Chrysophyceae 12 (3.63%) and Xanthophyceae 9 (2.72%). Similarly, the diatoms were highest in species richness (54.55%) followed by Cyanophyceae (18.18%),Chlorophyceae (12.12%), Dinophyceae (6.06%), Chrysophyceae (4.55%), and Xanthophyceae (4.55%). Among the zooplankton, the Copepods were the most abundant (54.89%). Others were Protozoa (14.13%), Polychaeta larvae (7.07%), Cyclopoida (5.43%), Cladocera (5.43%), Arthropoda (4.89%), Ostracoda (3.26%), Rotifera (2.72%),Malacostraca (1.09%), and Foraminiferida (1.09%). The copepods were highest in species richness (13), representing 36.11% of the total. The other zooplankton taxonomic groups were Protozoa (16.67%), Cyclopoida (11.11%), Ostracoda (8.33%), Rotifera (8.33%), Cladocera (5.56%), Malacostraca (5.56%), Arthropoda (2.78%), Polychaeta larvae (2.78%), and Foraminiferida (2.78%). We did not observe any preponderance of harmful phytoplankton or zooplankton in the Calabar River during the study. The river showed no evidence of stress beyond her carrying capacity, and there was no evidence of any harmful environmental conditions that is detrimental to recreational activities in the Calabar River. We assess Calabar River as being biologically suitable for contact recreational activities, from the point of view of her plankton characteristics

Population dynamics and gillnets selectivity of Chrysichthys nigrodigitatus (Lalepede 1803) in lower reaches of the Cross River estuary, Nigeria

Population Dynamics and gillnet selectivity of Chrysichthys nigrodigitatus (Lalepede 1803) in the lower reaches of the Cross River estuary of Nigeria was studied for two years (January 2008 – December 2009), with respect to selectivity, gillnet sizes and population of the species based on length frequency analysis. Estimates of growth parameters, asymptotic length (L∞) = 98.25cm and growth constant (K/year) = 0.96yr-1. Total mortality rate (Z) was 6.27 yr-1, natural mortality (M) = 1.22 yr-1, Fishing mortality (F) = 5.05 yr-1 and Exploitation rate (E) = 0.81. Significant correlation (r = 0.9140 – 0.9770 and r = 0.976 – 0.977). (P < Z0.05) was observed between mesh sizes of gillnets and mean values of the morphometric characteristics (such as half-circumference, total length and total weight) of the fish. There is low percentage frequency range of the number of fish caught in different mesh sizes, possibly with low hanging coefficient range (0.4-0.5). Gilling, snagging, wedging, entangling were observed in the selection of the fishes. In conclusion, selectivity in Chrysichthys nigrodigitatus gillnet fishery in the Cross River estuary may be moderately adequate despite the influence of several other factors. The selection distribution curve using 17.5cm estimated modal total length recommends the usage of 50mm mesh size and above for exploitation of the species.Keywords: Gillnet, Selectivity, Mortality, Length, Populatio

Onchocerciasis in the Upper Imo River Basin, Nigeria: Prevalence and Comparative Study of Waist and Shoulder Snips from Mesoen­demic Communities

Background: Onchocerciasis is endemic in the Imo River Basin, Nigeria. This study was aimed at assess­ing the prevalence and intensity of microfilaria of Onchocerca volvulus in the area. Methods: A cross-sectional study was carried out in the Okigwe Local Government Area, Imo State, Nige­ria. Two skin snips (one from the waist and another from the shoulder) were taken from 1024 individu­als examined. The survey coverage was high (91.8% of the study population). An individual was considered mf positive if either of the waist or shoulder snips or both were mf positive. The SPSS for Win­dows package was used for entering and analysis of data.Results: Thirty-seven percentage of those examined was positive for Onchocerca volvulus microfilariae (39.2% of males and 34.9% of females). The mf prevalence increased steadily with increasing age to reach 70.4% in the oldest age group. The overall mf Geometric Mean Intensity among mf positive individuals was 16 mf/skin snip and was significantly higher among males (18 mf/skin snip) than females (14 mf/skin snip) (p < 0.01). A scatter plot of microfilariae numbers in snips from the waist against numbers in snips from the shoulder of the same individuals, showed close correlation (Pearson's correlation coefficient = +0.90; p < 0.01), and those with mf intensities below 10 mf/snip had a more scattering tendency away from the regression line than those with higher mf intensities.Conclusion: Onchocerciasis is a public health concern in the area. Perhaps, 10 mf/snip is critical intensity threshold for reliable sampling using corneo-scleral punch

Clinical Manifestations of Mesoendemic Onchocerciasis in an Area with Multiple Filarial Species

"nBackground: The Imo River Basin, Nigeria is endemic for onchocerciasis, bancroftian filariasis, loaiasis and mansonellosis. This study was aimed at determining the clinical manifestations of onchocerciasis in this region. "nMethods: A cross-sectional study was carried out in 2006 in Umuowaibu I and Ndiorji commu­nities in Okigwe Local Government Area of Imo State, Nigeria. Consenting individuals were ex­amined for various gradations of skin manifestations, subcutaneous nodules, and visual im­pair­ments by qualified medical doctors. Five categories of skin manifestations were observed, namely permanent itching, onchodermatitis, atrophy of skin, leopard skin, and sowda. A total of 1024 individuals were examined. "nResults: The prevalence of the skin manifestations were permanent itching (2.5%), onchoder­ma­titis (3.9%), atrophy of the skin (5.8%), leopard skin (22.1%), and sowda (0.1%). The preva­lence of subcutaneous nodules was 25.3%, but 88.9% among the oldest age group, and mostly found in lower half of body. The majority of cases of visual acuity problems (6.8% overall prev­alence) were in the oldest age groups. Among those who were ≥ 20 years old, the prevalence of visual acuity problems was significantly higher in females than in males (χ2-test; P< 0.05). Only two of the examined persons were observed to be blind. "nConclusion: Clinical manifestations of onchocerciasis are perhaps more intense in the area prob­ably because of presence of endemic infections of other filarial species

Mansonellosis in the upper Imo River Basin, Nigeria

The Upper Imo River Basin is endemic for mansonellosis due to Mansonella perstans. No case of M. streptocerca microfilaraemia was found in the studied population. The prevalence of M. perstans microfilariae in the area was 12.5%. Microfilaraemia was higher among older individuals and there was no significant difference in prevalence between sexes. The overall mf GMI among mf positives was 98 mf/ml (103 mf/ml for males and 92 mf/ml for females). There was no significant difference between the overall mf GMI in males and females (t-test; p >0.05). It is generally believed that mansonellosis due to M. perstans does not cause any serious clinical sign or symptom, and consequently there was no examination for clinical manifestations related to this infection in the Upper Imo River Basin of the studied population.Keywords: mansonellosis, Imo River, epidemiologyGlobal Journal of Pure and Applied Sciences Vol. 11(4) 2005: 465-46

Lymphatic Filariasis in Nigeria; Micro-stratification Overlap Mapping (MOM) as a Prerequisite for Cost-Effective Resource Utilization in Control and Surveillance

Background Nigeria has a significant burden of lymphatic filariasis (LF) caused by the parasite Wuchereria bancrofti. A major concern to the expansion of the LF elimination programme is the risk of serious adverse events (SAEs) associated with the use of ivermectin in areas co-endemic with Loa filariasis. To better understand this, as well as other factors that may impact on LF elimination, we used Micro-stratification Overlap Mapping (MOM) to highlight the distribution and potential impact of multiple disease interventions that geographically coincide in LF endemic areas and which will impact on LF and vice versa. Methodology/Principal findings LF data from the literature and Federal Ministry of Health (FMoH) were collated into a database. LF prevalence distributions; predicted prevalence of loiasis; ongoing onchocerciasis community-directed treatment with ivermectin (CDTi); and long-lasting insecticidal mosquito net (LLIN) distributions for malaria were incorporated into overlay maps using geographical information system (GIS) software. LF was prevalent across most regions of the country. The mean prevalence determined by circulating filarial antigen (CFA) was 14.0% (n = 134 locations), and by microfilaria (Mf) was 8.2% (n = 162 locations). Overall, LF endemic areas geographically coincided with CDTi priority areas, however, LLIN coverage was generally low (<50%) in areas where LF prevalence was high or co-endemic with L. loa. Conclusions/Significance The extensive database and series of maps produced in this study provide an important overview for the LF Programme and will assist to maximize existing interventions, ensuring cost effective use of resources as the programme scales up. Such information is a prerequisite for the LF programme, and will allow for other factors to be included into planning, as well as monitoring and evaluation activities given the broad spectrum impact of the drugs used