BACKGROUND Methicillin-resistant Staphylococcus aureus (MRSA) is a leading human pathogen, and declining antibiotic efficacy has renewed interest in lytic bacteriophages, whose efficacy phenotypic assays predict poorly. OBJECTIVES To characterise the lysis and host-recognition modules of lytic S. aureus bacteriophages, and to determine how far the detectability of each module depends on the annotation source rather than on the genomes. METHODS Twenty-two S. aureus phage genomes from NCBI GenBank were processed through an identical detection funnel under three annotation sources: the deposited record, Pharokka and Phold. Modules were validated by InterPro, disrupted endolysins resolved by tBLASTn, and each domain aligned separately to measure identity. FINDINGS The LysK-type endolysin (CHAP-Amidase-SH3b) was conserved and detected identically under all three sources. Tail fibre/receptor-binding protein (RBP) detection was strongly source-dependent: 14 of 22 genomes from the deposited annotation, 20 of 22 after re-annotation, and 22 of 22 combined. Resolved by domain, conservation was scale-dependent: the amidase domain was invariant within species while SH3b varied by 5.7%. MAIN CONCLUSIONS Lysis-module conservation is independent of the annotation source; the apparent variability of host recognition is largely an artefact of incomplete deposited annotation. Module-level surveys require re-annotation before comparative claims.
BACKGROUND Blood donation candidates who are deferred are not targeted by any health policy. OBJECTIVES To describe sociodemographic characteristics of unsuitable blood donation candidates, the causes of unsuitability and compare the prevalence rates of transfusion-transmitted infections in deferred and eligible blood donors. METHODS A cross-sectional survey was conducted to obtain sociodemographic data and blood samples; 8,159 blood donation candidates were screened (21.1% rejected, 78.9% approved). A sample of 212 deferred candidates was established. FINDINGS Most rejected candidates were female, young adults, with high school or university education, self-declared white, born in the North region and single. Main reasons for unsuitability were low haemoglobin concentration, potential exposure to malaria and risky sexual behaviour. The comparison of seropositivity rates in deferred and eligible blood donation candidates generated the following prevalence ratios (PR) and respective 95% confidence intervals (CI): human immunodeficiency virus (HIV), PR = 6.75 (1.46 - 31.05), p = 0.046; syphilis, PR = 1.47 (0.46 - 4.64), p = 0.463; anti-HBc, PR = 2.84 (1.24 - 6.50); p = 0.023; anti-HCV, PR = 4.67 (1.06 - 20.58), p = 0,080; Chagas disease, PR = 60.75 (5.53 - 667.43), p = 0.003. MAIN CONCLUSIONS Treating anaemia in women and controlling malaria in Roraima will reduce the pool of rejected blood donation candidates in the State.
BACKGROUND The coronavirus disease 2019 (COVID-19) pandemic has intensified debates on causal explanation in biology, particularly regarding the integration of proximate mechanisms with broader ecological, historical, and socio-environmental determinants. Many accounts remain confined to a single explanatory level, limiting their capacity to address the complexity of pandemic emergence and control. OBJECTIVES This paper develops a causal account of the COVID-19 pandemic by placing into dialogue Leyes sin causa y causas sin ley en la explicación biológica, by Gustavo Caponi, and Donald Worster’s essay ‘Another Silent Spring’. METHODS The analysis adopts a conceptual and comparative approach, contrasting Caponi’s experimentalist account of causation, centred on intervention and invariance, with Worster’s environmental-historical interpretation of pandemic origins. The discussion is further informed by evolutionary medicine and epidemiology. FINDINGS Caponi’s framework clarifies the epistemic role of intervention, while Worster situates the pandemic within a long-term process of ecological transformation driven by human attempts to control natural systems. Together, these perspectives reveal a tension between control as explanation and control as a source of ecological instability. MAIN CONCLUSIONS The COVID-19 pandemic may be interpreted as a paradox of control: human efforts to manipulate biological and ecological processes generate conditions that increase systemic risk. The pandemic thus underscores the need to integrate biological, ecological, and socio-historical dimensions of causation in both explanation and prevention.
Despite concerns arising from a recent ship-associated outbreak on the M/V Hondius cruise, current evidence suggests that Andes virus (ANDV) poses a low pandemic risk. Nevertheless, viral evolution, ecological changes, and reservoir host dynamics could drive future emergence of ANDV, underscoring the need for improved surveillance, diagnostics, therapeutics, and vaccine preparedness.
BACKGROUND Chagas disease (CD) is a chronic, disabling vector-borne disease caused by Trypanosoma cruzi and transmitted to humans by infected triatomine insects during blood meals. CD is currently endemic in 21 Latin American countries and the United States of America, with factors such as climate change, urbanisation, and migration contributing to the expansion of the vector’s range from endemic to non-endemic regions. Globally, 44 countries have reported CD cases, indicating that it is an important public health problem. OBJECTIVES To document the presence and geographic distribution of Triatoma dimidiata and Triatoma barberi in previously unreported areas, and to assess their epidemiological relevance for CD. METHODS Molecular, entomological, and spot pattern analyses were performed. DNA was extracted from triatomines, the ITS2 region amplified, cloned, and sequenced. An extensive search for reports on triatomine in Oaxaca was conducted from 2019 to 2024, and a distribution map was generated. FINDINGS We report the range expansion of two species to communities in La Cañada region. The CD vector range expansion poses an increased risk of infection in newly affected communities, given the higher prevalence of CD in Oaxaca. MAIN CONCLUSIONS Awareness of triatomine distribution is essential to prevent the spread of CD into non-endemic areas and to identify emerging endemic zones for epidemiological surveillance and disease control.
