Seasonal variation and risks of potentially toxic elements in agricultural lowlands of central Cameroon.

Intensive urban agriculture is expanding in Cameroon, which increases the risks of environmental pollution, particularly in the lowlands. This study assessed the seasonal characteristics of some potentially toxic elements and their ecological risks during the dry and wet seasons in urban agricultural soils in four lowlands in Yaoundé. The area and seasonal variation of some potentially toxic elements (Cu, Pb, Zn, Cd, Cr, and Ni) were evaluated using mixed-effects modeling. The pollution status of these elements in the soil was evaluated and interpreted using parameters such as the single pollution (SPI) and Nemerow composite pollution (NCPI) indices. In addition, the effect of these metals in the environment was assessed using the potential ecological risk index (PERI). The distribution of all the studied elements showed an area effect, while a seasonal effect was only noticeable for Cu. The concentration of Cu, Pb, and Zn was higher than the recommended threshold values in one of the areas sampled, while Cr exceeded these threshold values in all areas during both seasons. Cr exhibited the highest SPI among all studied elements during the dry and wet seasons in all areas. Except for the NCPI in one area, where grade V (strong) soil pollution was recorded during the wet season, the soil from all the study areas exhibited a slight pollution level (grade III) with a mean NCPI between 1 and 2. The PERI value of all areas was below the reference values during both seasons, suggesting an overall low potential contamination risk of the soil biota. The results indicate that preventive action to limit the heavy metal contamination in the lowlands of Yaoundé needs to be taken, for instance, through the promotion of more sustainable use of agrochemicals like pesticides and mineral fertilizers.

One Health in the context of coronavirus outbreaks: A systematic literature review.

The ongoing coronavirus disease 2019 (COVID-19) pandemic threatens global health thereby causing unprecedented social, economic, and political disruptions. One way to prevent such a pandemic is through interventions at the human-animal-environment interface by using an integrated One Health (OH) approach. This systematic literature review documented the three coronavirus outbreaks, i.e. SARS, MERS, COVID-19, to evaluate the evolution of the OH approach, including the identification of key OH actions taken for prevention, response, and control. The OH understandings identified were categorized into three distinct patterns: institutional coordination and collaboration, OH in action/implementation, and extended OH (i.e. a clear involvement of the environmental domain). Across all studies, OH was most often framed as OH in action/implementation and least often in its extended meaning. Utilizing OH as institutional coordination and collaboration and the extended OH both increased over time. OH actions were classified into twelve sub-groups and further categorized as classical OH actions (i.e. at the human-animal interface), classical OH actions with outcomes to the environment, and extended OH actions. The majority of studies focused on human-animal interaction, giving less attention to the natural and built environment. Different understandings of the OH approach in practice and several practical limitations might hinder current efforts to achieve the operationalization of OH by combining institutional coordination and collaboration with specific OH actions. The actions identified here are a valuable starting point for evaluating the stage of OH development in different settings. This study showed that by moving beyond the classical OH approach and its actions towards a more extended understanding, OH can unfold its entire capacity thereby improving preparedness and mitigating the impacts of the next outbreak.

Vulnerability of farming communities to malaria in the Bole district, Ghana.

Malaria contributes substantially to the poor health situation in the northern region of Ghana, especially in the Bole district. This paper is an outcome of a study, which assessed the factors that influenced the vulnerability of farming households to malaria, as well as the economic burden of the malaria prevalence in the Bole District, Ghana. The multiple linear regression model was used to analyze the determinants of household's vulnerability to malaria, and to examine the relationship between the non-parametric dependent variable and dichotomous independent variables. The outcome of the study revealed an increase in malaria cases during the rainy season. Total direct cost of malaria care, number of people comprising the farming household, support for malaria prevention, information on mosquito breeding and development, and absenteeism from farm emerged as the main factors, which influenced the households' vulnerability to malaria. Direct and indirect costs of malaria treatment have negatively affected the households' budget. In addition, malaria treatment cost represented a substantial portion of poor farming household income. The direct cost was estimated to GH₵ 4059, and the indirect cost was estimated to GH₵ 4654. It was recommended to the government of Ghana to expand the National Malaria Control Program to the household level and make National Health Insurance Scheme more efficient.