International Journal of Pathogen Research

Household Habitat Modification Practices and Malaria Rapid Diagnostic Test Positivity among Adults in Ada West and North Tongu Districts, Ghana: A Cross-Sectional Analysis within a Cluster-Randomised Controlled Trial

Oscar Vetsi — 2026-10-29

Background: Household habitat modification may complement established malaria control measures, but evidence linking individual practices to malaria rapid diagnostic test (RDT) positivity remains limited.

Aims: To determine and compare the associations between household habitat modification practices and malaria rapid diagnostic test (RDT) positivity among adults in the intervention and control districts of a cluster-randomised controlled trial in southern Ghana.

Study Design: Cross-sectional analysis of end-line survey data from a parallel two-arm cluster-randomised controlled trial with two districts, each comprising several sub-district clusters, randomly allocated to either the intervention or control arm.

Place and Duration of Study: Seven sub-district clusters in Ada West (intervention; three clusters) and North Tongu (control; four clusters) Districts, Ghana, from July to December 2024.

Methodology: The intervention arm received habitat modification (drain construction and rehabilitation, landfilling, land levelling, and permanent covering of water-holding structures) within an integrated environmental management package; the control arm received standard national malaria control. At the end-line survey, one adult per sampled household (700 per arm) reported eight household practices and was tested with a combined HRP2/pLDH RDT, which was classified as positive if either antigen line appeared; microscopy was not performed. Associations were estimated within each arm using chi-square tests, crude odds ratios (OR), and mutually adjusted logistic regression (adjusted OR, aOR). Because each arm contained only three or four clusters, cluster-adjusted inference was not feasible. The estimates are therefore presented as exploratory individual-level associations, with a sensitivity analysis based on an assumed intracluster correlation.

Results: RDT positivity was 50.4% (353/700) in Ada West and 50.6% (354/700) in North Tongu. Drainage modification was associated with lower odds of RDT positivity in both arms (Ada West: 43.5% vs 55.8%; OR 0.61, 95% CI 0.45–0.82, P = .001; North Tongu: 40.4% vs 57.2%; OR 0.51, 95% CI 0.37–0.69, P < .001), as were covered water-storage containers, filling of ponds, pits, and depressions, and regular removal of standing water. Treatment of stagnant water bodies and inspection of breeding sites showed no association. After mutual adjustment, filling of ponds and pits remained associated in Ada West (aOR 0.62, 95% CI 0.44–0.87, P = .006), and drainage modification (aOR 0.60, 95% CI 0.43–0.83, P = .003) and container covering (aOR 0.66, 95% CI 0.48–0.92, P = .01) in North Tongu. Under a conservative allowance for clustering, most confidence intervals included 1.0.

Conclusion: Habitat modification practices targeting discrete, locatable habitats were associated with lower malaria RDT positivity in both districts. These associations are exploratory: they were imprecise once clustering was considered, are based on self-reported cross-sectional data, and cannot be interpreted as intervention effects. Factorial and longitudinal trials with more clusters, objectively verified coverage, and parasitological confirmation are needed before component-specific scale-up.

Spatial Dynamics and Bioclimatic Drivers of Airborne Cladosporium Spores: A Comparative Aerobiological Study Across Three Strategic Agricultural Regions of Madagascar

HANITRINIAINA Elis Karena — 2026-10-30

Spores of the genus Cladosporium are among the major biological components of the atmosphere and represent both a source of phytopathogenic inoculum and an important factor in respiratory allergies. The aim of this study was to analyse the spatial variability of biological pollution by Cladosporium spores in three agricultural areas of Madagascar: Ambatondrazaka, Amparafaravola, and Betafo.
Aeropalynological monitoring was conducted from April 1 to September 30, 2023, using Hirst-type volumetric traps (Lanzoni). Spores were identified under a light microscope at ×400 magnification, and results were expressed as daily concentrations (spores m⁻³) and as a Seasonal Fungal Index (SFI). Differences among the sites were analysed using non-parametric tests, geographic correlations, and hierarchical clustering.
Mean daily concentrations ranged from 11 spores m⁻³ in Amparafaravola to 187 spores m⁻³ in Ambatondrazaka. The total seasonal spore count (SFI) ranged from 1,956 in Amparafaravola to 34,165 in Ambatondrazaka, while intermediate values were observed in Betafo (3,000–4,000 spores). The operational benchmark of 80 spores m⁻³ was exceeded for 8 to 58 days depending on the site. Maximum concentrations ranged from 139 spores m⁻³ in Amparafaravola to 2,295 spores m⁻³ in Ambatondrazaka.
The timing of the seasonal peak showed a positive correlation with latitude, indicating a north–south gradient in seasonal dynamics. Hierarchical clustering identified groups of sites with similar seasonal profiles, regardless of their geographic proximity.
This study represents the first comparative spatial analysis of Cladosporium spores in agricultural areas of Madagascar and highlights a strong geographic heterogeneity in atmospheric biological pollution.

Hepatitis B Surface Antigen and Hepatitis D Antibody Positivity among Inmates of Jos Correctional Centre, Plateau State, Nigeria

Ajala Ese Kate — 2026-10-31

Background: Hepatitis B virus (HBV) and hepatitis D virus (HDV) share transmission pathways, and ongoing HDV replication requires HBV surface antigen. Evidence from correctional facilities in Nigeria remains limited. This study assessed hepatitis B surface antigen (HBsAg) and anti-HDV antibody positivity among inmates of Jos Correctional Centre.

Methods: In a cross-sectional serological survey, plasma samples from 235 incarcerated participants was tested for HBsAg using an enzyme-linked immunosorbent assay (ELISA). HBsAg-reactive samples were subsequently tested for anti-HDV antibodies by ELISA. Descriptive frequencies and Wilson 95% confidence intervals (CIs) were calculated; Fisher’s exact test was used for selected sex- and exposure-stratified HBsAg comparisons.

Results: HBsAg was detected in 43 of 235 participants (18.3%; 95% CI: 13.9–23.7%). Five of the 43 HBsAg-positive participants were anti-HDV positive (11.6%; 95% CI: 5.1–24.5%). HBsAg positivity was 42/227 (18.5%) among men and 1/8 (12.5%) among women (Fisher’s exact p = 1.00). Anti-HDV positivity occurred in five men and no women; only one HBsAg-positive woman was screened for anti-HDV. Small subgroup counts precluded reliable risk-factor inference.

Conclusion: HBsAg and anti-HDV antibody positivity were observed in this correctional population. The findings support access to HBV screening, vaccination of susceptible individuals, HDV testing after HBsAg detection, and linkage to clinical assessment. Anti-HDV positivity alone does not establish active HDV infection.

Molecular Characterization and Detection of Plasmid-Mediated Quinolone Resistance (qnrA, qnrB, qnrD) Genes among Multidrug-Resistant Salmonella enterica Serovar Typhi Isolates from Clinical Specimens in Bauchi, Northeastern Nigeria

H. I. Liyo — 2026-11-09

Background: Salmonella enterica serovar Typhi remains a leading cause of enteric fever with 9 million cases and 110,000 deaths annually, disproportionately affecting low- and middle-income countries (Lamichhane et al., 2024). Multidrug-resistant (MDR) S. typhi and plasmid-mediated quinolone resistance (PMQR) determinants, particularly qnr genes, pose a major public health threat within the One Health framework because of their potential for rapid horizontal dissemination via mobile genetic elements (Djordjevic et al., 2024; Argimón et al., 2021).

Aim: This study aimed to molecularly identify MDR S. typhi isolates and detect qnrA, qnrB and qnrD genes among clinical isolates in Bauchi, Northeastern Nigeria.

Place and Duration of Study: Department of Microbiology, Abubakar Tafawa Balewa University, Bauchi, and Abubakar Tafawa Balewa University Teaching Hospital (ATBUTH), Bauchi, Nigeria, between January 2024 and December 2024.

Methodology: This was a cross-sectional laboratory-based study. Ethical approval: ATBUTH/HREC/2024/012. A total of 138 clinical samples (blood, n = 66; stool, n = 72) were collected with informed consent. Samples were cultured on Salmonella-Shigella Agar and Xylose Lysine Deoxycholate Agar. Presumptive Salmonella isolates were confirmed biochemically (Triple Sugar Iron, citrate, urease, H2S, motility) and serologically using polyvalent O and H antisera. Antimicrobial susceptibility testing (AST) was performed using the Kirby–Bauer disc diffusion in accordance with CLSI M100, 33rd edition (Clinical and Laboratory Standards Institute, 2023) using 12 antibiotics: ampicillin (10µg), chloramphenicol (30µg), trimethoprim-sulfamethoxazole (25µg), ciprofloxacin (5µg), nalidixic acid (30µg), ceftriaxone (30µg), cefotaxime (30µg), azithromycin (15µg), gentamicin (10µg), tetracycline (30µg), amoxicillin-clavulanate (30µg) and ofloxacin (5µg). MDR was defined as resistance to ≥1 agent in ≥3 antimicrobial categories (Magiorakos et al., 2012). MDR isolates were confirmed by PCR targeting the 16S rRNA gene (RIBOSE-1/RIBOSE-2, 789bp), followed by Sanger sequencing and BLAST analysis (≥98.7% identity threshold) (Stackebrandt and Ebers, 2006; Altschul et al., 1990). PMQR genes (qnrA, 516 bp; qnrB, 469 bp; qnrD, 691 bp) were screened by gene-specific PCR (Robicsek et al., 2006; Cavaco et al., 2009) and phylogenetic analysis was performed in MEGA 11 using the Neighbour-Joining method, 1,000 bootstrap replicates and the Kimura two-parameter model (Kimura, 1980; Tamura et al., 2021).

Results: Five (3.62%) Salmonella isolates were recovered (blood: 2/66, 3.03%; stool: 3/72, 4.16%). Two isolates (40%) were multidrug-resistant (MDR) (resistant to ampicillin, chloramphenicol, SXT, nalidixic acid, tetracycline). Sequencing of the 16S rRNA gene showed 99.10% and 98.77% identity with S. typhi reference strains CP156169.1 and CP029896.1. Phylogenetic analysis clustered the isolates with global S. typhi strains. Among MDR isolates, qnrA was detected in 2/2 (100%), qnrB in 1/2 (50%), qnrD 0%. Overall occurrence in the study population: qnrA 2/138 (1.45%), qnrB 1/138 (0.72%).

Conclusion: This study confirms the circulation of PMQR determinants (qnrA, qnrB) among MDR S. typhi in Bauchi. Although the prevalence was low (1.45%), their presence in clinical isolates indicates a potential risk of reduced fluoroquinolone effectiveness. Continued molecular surveillance within a One Health framework, antimicrobial stewardship, and WASH interventions are recommended. Future studies should use whole-genome sequencing for plasmid characterization.

Fungi Associated with Tuber Spoilage and Their Pathogenicity in Makurdi, Benue State Nigeria

Alex Aduojo Iyaji — 2026-11-10

Background: Postharvest fungal spoilage of yam and sweet potato remains a major challenge in Nigeria and Africa at large. It affects food security, storage quality, and marketability of tuber crops.

Objective: This study aimed to isolate, identify, and assess the pathogenicity potential of fungi associated with yam and sweet potato spoilage in Makurdi, Benue State, Nigeria.

Methodology: Yam and sweet potatoes were obtained from farmers in Makurdi, Benue State. The yams were stored for five months and observed for rot. The experiment was a 2x4 factorial in a completely randomised design with tuber type (Yam and Sweet potato) and variety (White Yam, Water Yam, Cream-fleshed Sweet Potato, Orange-fleshed Sweet Potato). It was replicated three times, with a total of 10 tubers per lot. Thus, the total number of tubers was 240, consisting of 120 yams and 120 sweet potatoes. Fungal isolation was carried out at the end of the experiment. Identification of fungal isolates was conducted using macroscopic, microscopic, and molecular methods. The molecular characterisation involved DNA extraction, PCR amplification using ITS-1 and ITS-4 primers, agarose gel electrophoresis, sequencing, and BLAST analysis using the NCBI database. Pathogenicity testing was carried out on healthy yam and sweet potato tubers following Koch’s postulates. Data obtained were analysed using analysis of variance (ANOVA) and means were separated using Fisher’s least significant difference (FLSD) at 5% probability level.

Results: Three fungal species, namely Aspergillus fumigatus, Lasiodiplodia theobromae, and Rhizopus stolonifer were isolated from the tubers. Sweet potato tubers yielded Aspergillus fumigatus, and Rhizopus stolonifer only, while yam tubers yielded all three identified species. Molecular analysis showed high sequence similarity ranging from 96.04% to 98.99%. Pathogenicity tests also confirmed that all isolates were capable of inducing rot in healthy yam tubers. Rhizopus stolonifer caused the highest rot with a severity of 11.70 cm², followed by Aspergillus fumigatus (9.42 cm²) and Lasiodiplodia theobromae (7.82 cm²). The study further revealed that yam tubers harboured a greater diversity of fungal pathogens than sweet potato tubers.

Conclusion: Spoilage of yam and sweet potato in Makurdi is caused by fungal pathogens. The high pathogenicity of fungi such as Aspergillus fumigatus raises a public health concern due to the danger it poses to human health. It is therefore recommended that improved storage practices and environmentally friendly postharvest management strategies be adopted to reduce fungal spoilage and preserve the quality of tuber crops during storage.