Blaise Pascal BOUGNOM

Antimicrobial Resistance of Airborne Bacterial and Fungal Bioaerosols in Maternity Wards in Yaoundé, Cameroon

Merveille De-Dieu Kapou, Jean Samuel Eheth, Marie-Cecile Nkoumou Ambassa, Hom-Toro Christelle Sharon Pedene, Blaise Pascal Bougnom

Journal of Medical Science Biology and Chemistry

Health-care associated infections (HAIs) is still one of the most prevalent concerns within the maternity wards, but little is known about the prevalence of airborne microorganisms in sub-Saharan Africa. Therefore, this study aimed to assess the microbiological characteristics of the indoor air, the distribution of airborne bacteria and fungi, and their antimicrobial resistance pattern in four maternity hospitals and eight different wards in Yaoundé, Cameroon. A cross-sectional study was conducted from February to April 2023. Indoor air sampling was done by the sedimentation technique. Bacteria and fungi isolated were subjected to standard biochemical tests. The antimicrobial resistance testing to six antibiotics prescribed was carried out using the agar dilution method. Microbial growth was recorded in 76.8% of the sampled wards. Airborne microbial load varied from 2.00 ± 2.00 CFU in neonatal wards to 51.87 ± 29.36 CFU in the communal toilets. 196 isolates were obtained, consisting of 159 bacteria and 37 fungi. Predominant isolates were Gram-positive cocci (79.25%); Staphylococcus aureus constituted 43.88%. Non-fermentative Gram-negative bacilli, mostly Pseudomonas spp. accounted for 10.06% of the bacterial isolates. Moulds Aspergillus, Fusarium, Penicillium and Bipolaris were the prevalent fungi (43.24%). The highest resistance rate was noted in amoxicillin-clavulanic acid (32.6%), amoxicillin (21.7%) and metronidazole (20.9%). Drug-resistant bacteria occurred in all studied wards, with Saint-Thérèse Hospital being the one with the largest number of resistant isolates. These findings underscore the need for routine airborne monitoring, improved ventilation, and antimicrobial stewardship in Cameroonian maternity settings.

• #indoor air quality and microbial exposure
• #infection control in healthcare
• #antimicrobial agents and applications
• #antibiotic resistance

Environmental reservoirs of high-risk ESBL- and carbapenemase-producing E. coli and Klebsiella in maternity wards in Yaounde (Cameroon): Whole-genome sequencing and antimicrobial susceptibility studies

Gabriel Cedric Bessala, Germanie Delaisie Abomo, Rodrigue Ngamaleu, Félix Essiben, Nicole E. Wheeler, Michelle M. C. Buckner et 2 autre(s)

medRxiv

Abstract Background The hospital environment is increasingly recognized as a critical reservoir for antimicrobial-resistant (AMR) bacteria. In sub-Saharan Africa, maternity wards represent high-risk settings where environmental contamination poses a direct threat to vulnerable mothers and neonates. Despite this, there is a significant lack of data integrating phenotypic resistance with whole-genome sequencing (WGS) to understand antimicrobial resistance (AMR) in these settings. This study characterized the AMR patterns and genomic features of ESBL-producing Escherichia coli and Klebsiella spp. isolated from maternity ward surfaces in Yaounde, Cameroon. Methods A cross-sectional environmental study was conducted across four maternity wards. Isolates were identified via standard microbiological methods, and antimicrobial susceptibility testing against 13 antibiotics was performed following EUCAST 2024 guidelines. Short-read WGS was utilized to identify sequence types (STs), plasmid incompatibility groups, antibiotic resistance genes (ARGs), and virulence factors. Plasmid‒ARG association networks were constructed to visualize resistance dynamics. Results Nineteen ESBL-producing Enterobacterales were identified, comprising 15 E. coli and four Klebsiella isolates. High levels of multidrug resistance were observed against ciprofloxacin, penicillins, and third-generation cephalosporins. While the isolates remained sensitive to colistin and imipenem, alarming resistance to meropenem was detected. Genomic analysis revealed the presence of globally disseminated high-risk lineages, including E. coli ST131, ST1193, and ST410, alongside Klebsiella ST1324 and ST489. Critical resistance determinants, including ESBLs, AmpC enzymes, and carbapenemases (NDM and OXA-48-like), are frequently associated with epidemic plasmids such as IncF, IncA/C2, and IncL/M. Additionally, the isolates harboured virulence factors characteristic of extraintestinal pathogenic Enterobacterales . Conclusions The widespread presence of high-risk carbapenemase-producing clones on maternity ward surfaces identifies the hospital environment as a significant AMR reservoir in Yaounde. These findings highlight the urgent need for reinforced infection prevention and control (IPC) measures, robust antimicrobial stewardship, and the integration of genomic surveillance to safeguard highly susceptible maternal and neonatal populations from life-threatening infections.

• #antibiotic resistance in bacteria
• #neonatal and maternal infections
• #urinary tract infections management
• #antibiotic resistance

Genomic epidemiology of ESBL-producing Escherichia coli and Klebsiella pneumoniae across the human-animal-environment interface in peri-urban pig farms in Yaounde, Cameroon

Germanie Delaisie Abomo, Gabriel Cedric Bessala, Isaac Dah, Michelle M. C. Buckner, Jan‐Ulrich Kreft, Blaise Pascal Bougnom

medRxiv

ABSTRACT Background Livestock production systems in peri-urban areas are associated with high levels of interaction between humans, animals, and the environment, which may contribute to the dissemination of antimicrobial resistant bacteria. However, genomic characterization of resistant bacteria in the interconnected systems of humans, animals, and the environment in low- and middle-income countries like Cameroon is very limited. Methods This study was undertaken to investigate the ESBL-producing E. coli and K. pneumoniae in the peri-urban pig production systems in Yaounde, Cameroon, through the application of the One Health genomic approach. A total of 338 samples were collected from humans, pigs, and the environment. Enterobacterales were isolated using standard microbiological procedures, followed by antimicrobial susceptibility testing of the isolated bacteria using the Kirby-Bauer disk diffusion method based on the EUCAST breakpoints. Ten multidrug-resistant Enterobacterales with similar resistance profiles were sequenced to identify their sequence types, resistance determinants, plasmid replicons, and virulence determinants. Results Enterobacterales were found in 187 samples, comprising 38 human, 98 pig, and 51 environmental samples. E. coli (166 isolates) was the most prevalent species, followed by K. pneumoniae (100 isolates). Whole-genome sequencing revealed eight E. coli and two K. quasipneumoniae isolates from human, pig, wastewater, and farm environmental samples. The E. coli isolates represented seven sequence types, including the globally successful ST410 lineage. Notably, E. coli ST3580 was found in human and environmental samples from the Afanoyoa farm in different sampling months, while K. quasipneumoniae ST1535 was found in human and pig samples from the Etoudi farm in different months. All genomes encoded ESBL genes, with bla CTX-M-15 being the most prevalent, accompanied by other resistance genes to various antibiotic classes and several plasmid incompatibility groups. Conclusions These results show the circulation of genetically diverse ESBL-producing E. coli and K. pneumoniae in human, animal, and environmental reservoirs in peri-urban pig farming systems and the potential for cross-reservoir persistence of particular lineages. Improved One Health antimicrobial resistance surveillance and stewardship are critical to address antimicrobial resistance in rapidly urbanizing environments.

• #escherichia coli research studies
• #antibiotic resistance in bacteria
• #salmonella and campylobacter epidemiology
• #klebsiella pneumoniae

Genotype-specific disinfection protocols enable reliable in vitro culture from mature field-harvested maize seeds

Danielle Christelle Tinak Ekom, Victorine Lombeko Obe Tomo, Aminatou Mongoue Fanche, Curtis Ivan Signi, Nelly Gaelle Sitcha Tchouatcha, Alain Martial Sontsa-Donhoung et 3 autre(s)

Discover Plants.

Disinfection of field-harvested maize seeds remains a major challenge for in vitro culture, especially in resource-limited settings. Developing reproducible, genotype-responsive protocols is essential to expand access to plant biotechnology. We evaluated eleven disinfection treatments across four maize genotypes (ATP, CHH, CHABA, KASSAI) using mature seeds and embryos. Treatments ET2, ST1, ST2, and controls supported high germination but allowed fungal persistence, while ET3, ST3, and ST5 achieved near-complete microbial suppression at the cost of reduced viability. Microbial profiling revealed dominant fungal ( Fusarium , Penicillium ) and 10 bacterial isolates contaminants. Genotype-specific responses were evident, underscoring the need for tailored approaches. This study validates mature field-harvested maize seeds as reliable explants for in vitro culture when disinfection protocols are optimized. The findings support scalable, low-cost tissue culture systems and contribute to sustainable biotechnology practices aligned with food security and equitable access to innovation.

• #plant tissue culture and regeneration
• #transgenic plants and applications
• #plant disease management techniques
• #germination

Whole-genome sequencing reveals high-risk ESBL and carbapenemase-producing Enterobacterales on maternity ward surfaces in Cameroon

Gabriel Cedric Bessala, Germanie Delaisie Abomo, Henri Rodrigue Njengoue Ngamaleu, Félix Essiben, Nicole E. Wheeler, Michelle M. C. Buckner et 2 autre(s)

Scientific Reports

Abstract The hospital environment is increasingly recognized as a critical reservoir for antimicrobial-resistant (AMR) bacteria. In sub-Saharan Africa, maternity wards represent high-risk settings where environmental contamination poses a direct threat to vulnerable mothers and neonates. Despite this, there is a significant lack of data integrating phenotypic resistance with whole-genome sequencing (WGS) to understand antimicrobial resistance (AMR) in these settings. This study characterized the AMR patterns and genomic features of ESBL-producing Escherichia coli and Klebsiella spp. isolated from maternity ward surfaces in Yaounde, Cameroon. A cross-sectional environmental study was conducted across four maternity wards. Isolates were identified via standard microbiological methods, and antimicrobial susceptibility testing against 13 antibiotics was performed following European Committee on Antimicrobial Susceptibility Testing (EUCAST) 2024 guidelines. Short-read WGS was utilized to identify sequence types (STs), plasmid incompatibility groups, antibiotic resistance genes (ARGs), and virulence factors. Plasmid-ARG association networks were constructed to visualize resistance dynamics. Nineteen ESBL-producing Enterobacterales were identified, comprising 15 E. coli and four Klebsiella spp. isolates. High levels of multidrug resistance were observed against ciprofloxacin, penicillins, and third-generation cephalosporins. While the isolates remained sensitive to colistin and imipenem, alarming resistance to meropenem was detected. Genomic analysis revealed the presence of globally disseminated high-risk lineages, including E. coli ST131, ST1193, and ST410, alongside K. pneumoniae ST1324 and K. quasipneumoniae ST489. Critical resistance determinants, including ESBLs, AmpC enzymes, and carbapenemases ( bla NDM , bla OXA-48-like ), were associated with epidemic plasmids such as IncF, IncA/C2, and IncL/M. Additionally, the isolates harboured virulence factors characteristic of extraintestinal pathogenic Enterobacterales . The widespread presence of high-risk carbapenemase-producing clones on maternity ward surfaces identifies the hospital environment as a significant AMR reservoir in Yaounde. These findings highlight the urgent need for reinforced infection prevention and control (IPC) measures, robust antimicrobial stewardship, and the integration of genomic surveillance to safeguard highly susceptible maternal and neonatal populations from life-threatening infections.

• #antibiotic resistance in bacteria
• #pharmaceutical and antibiotic environmental impacts
• #antibiotic use and resistance
• #klebsiella pneumoniae

High Environmental Contamination by Extended-Spectrum β-Lactamase-Producing Escherichia coli and Klebsiella pneumoniae in Maternity Wards of Yaounde, Cameroon

Gabriel Cedric Bessala, Germanie Delaisie Abomo, Yolande Francine Onomo Medja, Michèle Debora Abanda Assena, Anaïs Alexandra Dooh, Félix Essiben et 2 autre(s)

Journal of Life Science and Public Health

Antimicrobial resistance (AMR) is an enormous global health burden, particularly in maternity and neonatal wards of hospitals where patients are extremely vulnerable to healthcare-associated infection. The objective of this study was to investigate the presence and cefotaxime-resistant Gram-negative bacteria (CRGNB) antimicrobial resistance profiles of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae contaminating environmental surfaces within Yaoundé, Cameroon maternity hospitals. From January to November, 1,519 environmental samples were collected from four maternity hospitals: Yaoundé Central Hospital (YCH), Cité-Verte District Hospital (CVDH), Nkolndongo District Hospital (NDH), and Odza District Hospital (ODH). The samples were cultured on selective media for CRGNB and antimicrobial susceptibility tested by conventional methods. CRGNB were isolated from all facilities with the highest contamination rate in NDH (230 ± 97 CFU/cm²). Significant space and time differences (p < 0.05) were observed with the peaks during March to May. Seventy-one CTX-resistant Enterobacteriaceae were recovered, of which the majority came from YCH (35.2%) and CVDH (29.6%), comprising E. coli (54%) and K. pneumoniae (46%). Alarming was the observation that all the ESBL-producing E. coli (n = 14) and K. pneumoniae (n = 4) isolates were 100% resistant to meropenem but 100% susceptible to imipenem and colistin. Similarly high rates of resistance were also found for aztreonam and cefotaxime (92.9%). The finding of meropenem resistance in ESBL-producing environmental isolates from maternity wards is a significant public health issue, indicating emerging porin- and efflux-mediated carbapenem resistance. Increased infection control, antimicrobial stewardship, and regular environmental surveillance are urgently necessary to block dissemination of such multidrug-resistant pathogens in healthcare facilities.

• #antibiotic resistance in bacteria
• #antimicrobial agents and applications
• #urinary tract infections management
• #klebsiella pneumoniae

Antibiotic Enteric Resistant Bacteria are Abundant on Lettuce from Urban Agriculture in the City of Yaounde

Merveille Tamema Masse, Blaise Pascal Bougnom, Brunelle Tchakounte Betbui

International Journal of Trend in Scientific Research and Development

• #urban agriculture and sustainability
• #child nutrition and water access
• #dengue and mosquito control research
• #enteric bacteria

Effect of Cattle Manure Wood-Ash Compost on Chemical, Physical and Microbial Properties of Two Acid Tropical Soils

Blaise Pascal Bougnom, Aristide Molemb Nemete, Guy Faustin Mbassa, Pierre Effa Onomo, François‐Xavier Etoa

Agricultural Journal

• #composting and vermicomposting techniques
• #compost
• #manure
• #soil water

Effects of Cattle Manure Wood-Ash Compost on Some Chemical, Physical and Microbial Properties of Two Acid Tropical Soils

Blaise Pascal Bougnom, Aristide Molemb Nemete, GuyFaustin Mbassa, Pierre Effa Onomo, François‐Xavier Etoa

International Journal of Advances in Scientific Research and Engineering

A field study was conducted to assess the potential of cattle manure wood-ash compost in order to improve soil fertility and productivity in two areas in the centre region of Cameroon distant of 200 km. The farms were amended with four types of compost, C1 (100% cattle manure compost), C2 (95% cattle manure with 10% wood ash admixture), C3 (90% cattle manure compost and 10% wood ash admixture), and C4 (85% cattle manure compost and 15% wood ash admixture). Soybean was the growing plant during the experiment which lasted three months. After the harvesting, physical, chemical, biological and plant parameters were evaluated. The compost significantly increased soil pH, Electrical conductivity, total organic carbon, total nitrogen, concentrations of Ca 2+ , Mg 2+ , K + , Na + , and total phosphorus. The composts also had a stimulatory effect on the total soil bacteria and fungi, cellulase and protease activities. Improvement soil physical, chemical and microbial parameters enhanced biomass production and yield. In summary, cattle manure wood-ash composts could be used for alleviating soil acidity and improve soil fertility of tropical acid soils. Future research is needed to address its sustainability in a long-term study.

• #agriculture and rural development research
• #compost
• #manure
• #soil water

Antibiotic resistance genes are abundant and diverse in raw sewage used for urban agriculture in Africa and associated with urban population density

Blaise Pascal Bougnom, Alan McNally, François-X. Etoa, Laura J. V. Piddock

Environmental Pollution

• #antibiotic resistance in bacteria
• #pharmaceutical and antibiotic environmental impacts
• #fecal contamination and water quality
• #resistome

Figure 1. African map showing the investigated countries and cities. 1: Ouagadougou; 2: Ngaoundere; and 3: Yaounde;Table 1. DNA sequence read metrics of the six metagenomic samples

Blaise Pascal Bougnom

Data Archiving and Networked Services (DANS)

African map showing the investigated countries and cities, and the DNA sequence read metrics of the six metagenomic samples from soil from irrigated fields (IRI) and non-irrigated fields (NIR) based on MG-RAST annotation.

• #genetics, bioinformatics, and biomedical research
• #metagenomics
• #table (database)
• #sequence (biology)

Wastewater used for urban agriculture in West Africa as a reservoir for antibacterial resistance dissemination

Blaise Pascal Bougnom, Cheikna Zongo, Alan McNally, Vito Ricci, F. X. Etoa, Sören Thiele‐Bruhn et 1 autre(s)

Environmental Research

• #antibiotic resistance in bacteria
• #pharmaceutical and antibiotic environmental impacts
• #gut microbiota and health
• #biology

Wastewater for Urban Agriculture: A Significant Factor in Dissemination of Antibiotic Resistance

Blaise Pascal Bougnom, Laura J. V. Piddock

Environmental Science & Technology

I t is estimated that antibiotic-resistant bacteria cause 23 000 and 25 000 deaths in the United States and Europe, respectively; 1 the situation is similar worldwide and even worse in low and middle income countries (LMICs) where a high infectious disease burden is coupled with rapid emergence and spread of microbial drug resistance. 1 Populations from LMICs are facing an increasing rise in numbers of antibioticresistant bacteria; members of the Enterobacteriaceae and Pseudomonaceae are the most frequently isolated bacteria from clinical samples. 2 Deaths from antibiotic-resistant bacteria are under-reported, 1 but available data indicates that a large number of neonatal deaths due to drug-resistant sepsis occur every year in India, Pakistan, Nigeria, and in the Democratic Republic of Congo. 2 Taking this into account, it is no surprise that globally by 2030 infectious diseases are predicted to be one of the most frequent causes of death. 1 The important role of the environment in the dissemination of antibiotic resistance is acknowledged, and the aquatic environment has been shown to act both as a natural reservoir and a channel for the spread of clinically relevant antibiotic resistance traits. 3Approximately 50-90% of antibiotics are excreted in urine or faeces from people or animals, either in their original formulation, partly degraded or as metabolites.Consequently, due to the higher consumption of antibiotics without control in LMICs, huge quantities of antibiotics end up in water ecosystems. 4To survive in the presence of antibiotics, bacteria have evolved a plethora of different antibiotic

• #pharmaceutical and antibiotic environmental impacts
• #antibiotic use and resistance
• #antibiotic resistance in bacteria
• #citation

The Problem of Spore‐Forming Bacteria in Food Preservation and Tentative Solutions

Stève Olugu Voundi, Maximilienne Ascension Nyegue, Blaise Pascal Bougnom, François‐Xavier Etoa

There are about 200 species of spore-producing bacteria included in about 25 genera usually belonging to the Bacillaceae family. This chapter describes the phenomenon by which the vegetative cell becomes a spore (sporulation), as well as the reverse process (germination). It presents the structure of a spore, since it is from this structure that spores derive their high resistance. The chapter then discusses the problems of spore-forming bacteria in the food domain and different approaches to control them. In the food industry, the sporulation step is of major interest as it is the phenomenon that leads not only to the acquisition, but also to the extension of spore resistance. Under electron microscopy, bacterial spores reveal structures that are greatly different from those of the initial vegetative cells. One of the fundamental problems of spore forming bacteria is the high resistance of their spores, which limits the effectiveness of food sterilization methods.

• #probiotics and fermented foods
• #microbial inactivation methods
• #enterobacteriaceae and cronobacter research
• #spore

Potential of Cattle Manure Ash to Improve Soil Fertility and Groundnut (Arachis hypogea L.) Growth in the Adamawa Region (Cameroon)

D. Nwaga, Blaise Pascal Bougnom, C. Megueni, J. Mouna

Global Journal of Agricultural Innovation Research & Development

Groundnut (Arachis hypogea L.) production is a key farming activity in Cameroon, since it substantially contributes to human nutrition, economic wealth of farmers and soil fertility. Most cropping systems in sub Saharan Africa are limited by low soil fertility and subjected to the slash-and-burn agriculture. A study was conducted to investigate the potential of cattle manure ash, derived from cooking activities as soil conditioner in order to improve soil fertility and groundnut performances in two sites in the Adamawa region (Cameroon). The results showed that cattle manure ash slightly increased soil pH, soil moisture, SOM, Corg and C/N ratio in amended plots. Cattle manure ash improved nodule weight and increased arbuscular mycorrhizal fungi colonization in one site, that was translated to better N assimilation, and dry weight of both groundnut varieties used in the study. Future studies are needed to evaluate the full potential of cattle manure ash application, alone and/or associated with others organic wastes for sustainable agriculture in the tropics.

• #agronomic practices and intercropping systems
• #arachis
• #manure
• #agronomy

Compost: A Tool to Sustainable Urban and Peri-Urban Agriculture in Sub-Saharan Africa?

Blaise Pascal Bougnom, Onana Boyomo, D. Nwaga, Jean Justin Essia Ngang, F. X. Etoa

Sustainable development and biodiversity

• #urban agriculture and sustainability
• #food waste reduction and sustainability
• #agriculture
• #municipal solid waste

Residues from renewable energy production: Their value for fertilizing pastures

Blaise Pascal Bougnom, C. Niederkofler, Brigitte A. Knapp, E. Stimpfl, Heribert Insam

Biomass and Bioenergy

• #bioenergy crop production and management
• #soil carbon and nitrogen dynamics
• #anaerobic digestion and biogas production
• #biogas

Soil microbial dynamics in organic (biodynamic) and integrated apple orchards

Blaise Pascal Bougnom, B. Greber, Ingrid H. Franke‐Whittle, Claudio Casera, Heribert Insam

Organic Agriculture

• #mycorrhizal fungi and plant interactions
• #horticultural and viticultural research
• #plant physiology and cultivation studies
• #organic farming

Organic Orcharding and Use of Wood Ash Compost

Blaise Pascal Bougnom

• #composting and vermicomposting techniques
• #forest biomass utilization and management
• #compost
• #waste management

Possible Use of Wood Ash and Compost for Improving Acid Tropical Soils

Blaise Pascal Bougnom, Brigitte A. Knapp, François‐Xavier Etoa, Heribert Insam

• #clay minerals and soil interactions
• #aluminum toxicity and tolerance in plants and animals
• #heavy metals in environment
• #lime

Designer compost with biomass ashes for ameliorating acid tropical soils: Effects on the soil microbiota

Blaise Pascal Bougnom, Brigitte A. Knapp, Dana Elhottová, Anna Koubová, François‐Xavier Etoa, Heribert Insam

Applied Soil Ecology

• #aluminum toxicity and tolerance in plants and animals
• #clay minerals and soil interactions
• #vitamin c and antioxidants research
• #compost

Composts with and without wood ash admixture for the management of tropical acid soils: chemical, physical and microbiological effects

Blaise Pascal Bougnom, Heribert Insam, F. X. Etoa

EGU General Assembly Conference Abstracts

• #clay minerals and soil interactions
• #recycling and utilization of industrial and municipal waste in materials production
• #soil water
• #environmental science

Composts with wood ash addition: A risk or a chance for ameliorating acid tropical soils?

Blaise Pascal Bougnom, Johannes Mair, François‐Xavier Etoa, Heribert Insam

Geoderma

• #clay minerals and soil interactions
• #aluminum toxicity and tolerance in plants and animals
• #heavy metals in environment
• #amendment