Identification of molecular determinants of antibiotic resistance in some fish farms of Ghana.

Antimicrobial resistance is a global health challenge caused by the ability of microorganisms including bacteria, fungi, protozoans and viruses to survive the effects of drugs that hitherto were effective against them. This study sought to investigate the presence of antibiotic-resistant bacteria and their corresponding molecular determinants in fish farms of the Central and Western Regions of Ghana. Management practices and antibiotic use at the fish farms were obtained through the administration of a questionnaire. Coliform and Gram-positive bacterial loads of catfish (Clarias gariepinus), tilapia (Oreochromis niloticus) intestinal microbiota, and pond water samples recovered on MacConkey Agar and Mannitol Salt Agar were determined. Bacterial isolates were identified using various biochemical assays. Antibiotic resistance profiles and possible responsible genes of bacterial isolates were determined using the disc diffusion and Polymerase Chain Reaction (PCR) methods respectively. The study revealed that none of the fish farm managers admitted using antibiotics for prevention and treatment of diseases and no major disease outbreak had ever been recorded. Bacterial loads of pond water exceeded the acceptable level of ≤100 E. coli and <10 coliforms per mL for wastewater recommended for use in fish farming. In all, 145 bacterial isolates comprising 99 Gram negative and 46 Gram-positive bacteria were stored and identified. Most isolates were resistant to at least an antibiotic. Both Gram-negative and Gram-positive bacteria were highly resistant to beta-lactam antibiotics with a corresponding high percentage detection of the bla TEM gene compared to other classes of antibiotics. This study has revealed the presence of various molecular determinants of antibiotic resistance including bla TEM, cmIA, qnrS, tetB and bla CTX-M, in multidrug-resistant bacteria at some fish farms in Ghana. There is the need to increase awareness about risks associated with the misuse and overuse of antibiotics by humans and the potential risk of spread of multi-drug resistant-bacteria in the environment.

Bioaccumulation of metals in the planktonic food web in the Gulf of Guinea.

Metal contamination is a threat for marine ecosystems from an environmental, economic and public health perspective, particularly in regions where local communities rely on marine resources such as the Gulf of Guinea. Plankton are the point of entry for metals in the marine food web, potentially contaminating seafood. We investigated the bioaccumulation of 12 metals in three size classes of plankton from the coast of Ghana. Metal concentrations were high in the micro- and mesoplankton, in particular for Mn, Mo and Zn (up to 100 mg kg-1) and Fe (>100 mg kg-1). All metals significantly bioaccumulated (103-106 L kg-1) and the bioaccumulation increased from the smallest to larger size fractions, suggesting a biomagnification. These metals included the highly toxic elements As, Cd and Pb. Our results highlight the need to monitor metal occurrence in the Gulf of Guinea, to reduce pollution and ensure food safety, in accordance with the UN SDG #14.

Using of intensity analysis approach in Benin coastal zone (West Africa) to assess land use/land cover change for further decision making.

Coastal areas are fruitful environments with a complex diversity of ecosystems. These areas are very sensitive and therefore, changes in the region of interest (ROI) require special attention due to the consequences. The changes observed in the coastal zone of Benin, such as: coastal erosion, the decrease of mangrove ecosystems and its consequences, and the pressure on agricultural land, have motivated this study, which aims to assess land use land cover in the coastal zone of Benin in order to better anticipate the phenomena of loss and fragmentation of ecosystems and to provide guidelines for policy-making. To achieve this objective, remote sensing and field surveys were used. Spot and Landsat satellite images of the years 1991-2006 and 2021 have been uploaded to regards. cnes.fr and USGS. Direct field observations and group discussions to determine the driving forces behind the changes were conducted. Supervised classification using the Maximum Likelihood approach of ENVI software was used and QGIS 3.16 to process the data. Significant changes have been observed in the coastal zone our study area over the past thirty years. During the period 1991-2006, palm fields constituted the largest land use with 84786 ha or 28.9% of the total area. This occupation will decrease over time to reach 66773.2 ha in 2006 (22.7% of the total area) and 27406.5 ha or 7.2% of the total area in 2021. Classes such as Mosaic of crop and out of crop, dense forest have experienced the same evolution while the opposite trend is observed in built-up areas. From 11543 ha or 3.9% of the total area in 1991, this class has increased to 25138 ha or 8.7% of the total area in 2006 and 44418.5 ha or 15.1% in 2021. Urbanization and the need for agricultural land have been identified as driving forces behind these changes and Markov chain analysis reveals future regression of coastal ecosystems such as mangroves, dense forest, swamp, and crop ender palm. These outcomes have far-reaching policy direction of environmental sustainability target in Benin coast.

Human health risk assessment from heavy metals in three dominant fish species of the Ankobra river, Ghana.

This study assessed heavy metal contamination of fish and its associated health risk to communities around the Ankobra River in the Western Region of Ghana. Species of fish randomly collected from different sections of the river were analyzed for Cd, Ni, Zn, Pb, Mn, Hg, As, Co and Cr using Atomic Absorption Spectrophotometry. Three commonly consumed fish species, Clarias gariepinus, Sarotherodon melanotheron and Pseudotolithus senegalensis, were analyzed. The health risks were assessed based on the potential non-carcinogenic effect associated with the daily consumption of fish by communities around the river. Concentrations of all the metals were higher in gills than the muscles of all three species. On average, levels of Mn (6.65 ± 7.30 mg.kg-1), Zn (2.24 ± 1.99 mg.kg-1) and Hg (3.06 ± 1.53 mg.kg-1) in all three species were above the permissible limits recommended by the Wealth Health Organization. The health risk estimated for all the heavy metals was < 1, significantly below the ≥ 1 index associated with the incidence of cancer. This suggests that fish species examined in this study pose no significant non-carcinogenic risk and are safe for human consumption.

Physical distancing and risk of COVID-19 in small-scale fisheries: a remote sensing assessment in coastal Ghana.

The novel coronavirus is predicted to have dire implications on global food systems including fisheries value chains due to restrictions imposed on human movements in many countries. In Ghana, food production, both agriculture and fisheries, is exempted from restrictions as an essential service. The enforcement of COVID-19 prevention protocols, particularly social distancing, has been widely reported in Ghana's agricultural markets whereas casual observations and media reports on fish landing sites suggest no such enforcements are in place. This study aimed to provide sound scientific evidence as a basis for informed policy direction and intervention for the artisanal fishing sector in these challenging times. We employed an unmanned aerial vehicle in assessing the risk of artisanal fishers to the pandemic using physical distancing as a proxy. From analysis of cumulative distribution function (G-function) of the nearest-neighbour distances, this study underscored crowding at all surveyed fish landing beaches, and identified potential "hotspots" for disease transmission. Aerial measurements taken at times of peak landing beach activity indicated that the highest proportion of people, representing 56%, 48%, 39% and 78% in Elmina, Winneba, Apam and Mumford respectively, were located at distances of less than one metre from their nearest neighbour. Risk of crowding was independent of the population at the landing beaches, suggesting that all categories of fish landing sites along the coast would require equal urgency and measured attention towards preventing and mitigating the spread of the disease.

Multiple Antibiotic Resistance-Coliform Bacteria in Some Selected Fish Farms of the Central Region of Ghana.

This study aimed at assessing the quality of water and fishery products as well as the antibiotic resistance status of some selected fish farms of the Central Region of Ghana. Interview guides were administered to farmers to get data on farming practices and antibiotic use. Total coliform loads of catfish (Clarias gariepinus), tilapia (Oreochromis niloticus), and water samples were determined. Coliforms were identified through various biochemical assays, and their antibiotic resistance patterns were determined. Generally, the total coliform loads of water samples significantly surpassed those of fish samples (p < 0.05). The maximum and minimum antibiotic resistance percentages were recorded for ampicillin (96.83%) and gentamicin (6.35%), respectively. Although farmers stated that antibiotics were sparingly used, coliform bacteria isolated exhibited various antibiotic resistance patterns. Four out of six fish farms harboured some coliforms with multiple antibiotic resistance (MAR) indices above 0.2, an indication that these bacteria originated from potentially dangerous sources where antibiotics are regularly used.

Pollen-mediated gene flow and seed exchange in small-scale Zambian maize farming, implications for biosafety assessment.

Gene flow in agricultural crops is important for risk assessment of genetically modified (GM) crops, particularly in countries with a large informal agricultural sector of subsistence cultivation. We present a pollen flow model for maize (Zea mays), a major staple crop in Africa. We use spatial properties of fields (size, position) in three small-scale maize farming communities in Zambia and estimate rates of cross-fertilisation between fields sown with different maize varieties (e.g. conventional and transgene). As an additional factor contributing to gene flow, we present data on seed saving and sharing among farmers that live in the same communities. Our results show that: i) maize fields were small and located in immediate vicinity of neighboring fields; ii) a majority of farmers saved and shared seed; iii) modeled rates of pollen-mediated gene flow showed extensive mixing of germplasm between fields and farms and iv) as a result, segregation of GM and non-GM varieties is not likely to be an option in these systems. We conclude that the overall genetic composition of maize, in this and similar agricultural contexts, will be strongly influenced both by self-organised ecological factors (pollen flow), and by socially mediated intervention (seed recycling and sharing).

Detection of transgenes in local maize varieties of small-scale farmers in eastern cape, South Africa.

Small-scale subsistence farmers in South Africa have been introduced to genetically modified (GM) crops for more than a decade. Little is known about i) the extent of transgene introgression into locally recycled seed, ii) what short and long-term ecological and socioeconomic impacts such mixing of seeds might have, iii) how the farmers perceive GM crops, and iv) to what degree approval conditions are followed and controlled. This study conducted in the Eastern Cape, South Africa, aims primarily at addressing the first of these issues. We analysed for transgenes in 796 individual maize plants (leaves) and 20 seed batches collected in a village where GM insect resistant maize was previously promoted and grown as part of an governmental agricultural development program over a seven year period (2001-2008). Additionally, we surveyed the varieties of maize grown and the farmers' practices of recycling and sharing of seed in the same community (26 farmers were interviewed). Recycling and sharing of seeds were common in the community and may contribute to spread and persistence of transgenes in maize on a local or regional level. By analysing DNA we found that the commonly used transgene promoter p35s occurred in one of the 796 leaf samples (0.0013%) and in five of the 20 seed samples (25%). Three of the 20 seed samples (15%) included herbicide tolerant maize (NK603) intentionally grown by the farmers from seed bought from local seed retailers or acquired through a currently running agricultural development program. The two remaining positive seed samples (10%) included genes for insect resistance (from MON810). In both cases the farmers were unaware of the transgenes present. In conclusion, we demonstrate that transgenes are mixed into seed storages of small-scale farming communities where recycling and sharing of seeds are common, i.e. spread beyond the control of the formal seed system.

Rural perspectives on HIV/AIDS prevention: a comparative study of Thailand and Ghana.

The paper compares rural perspectives in Thailand and Ghana on the level of condom acceptance in sexual relations, willingness to test oneself for HIV before and in marriage and sources of information on HIV/AIDS. We also compared the policy approaches to combating HIV/AIDS in both countries. The results indicates that in the villages studied in Thailand, all single men and the majority of the single women were in favour of using condoms in sexual relations. This group also showed a positive attitude to HIV/AIDS test before and in marriage. However, married men in rural Thailand disapproved of the use of condoms with their wives but married women in the sample population were open to the possibility of using condoms. Both married men and women were strongly against HIV/AIDS test in marriage. In contrast to Thailand, most single men in the communities studied in Ghana showed a disapproval to the use of condoms in sexual relations. However, they condoned HIV test before marriage. Married men and women in rural Ghana were against the use of condoms in sexual relations as well as HIV/AIDS test in marriage. In order to mitigate mother-to-child transmission, the Thais applied anti-retroviral drug care for HIV positive pregnant women during pregnancy and after delivery. In Ghana on the other hand, pregnant women were subject to HIV test and counselling. The mode of information acquisition on HIV/AIDS in both countries were through the media, campaigns and village volunteers. Finally, we observed that fighting poverty is a sine qua non for the success of any HIV/AIDS eradication programme.