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“Now that the baby is out, I can be vaccinated” a qualitative study on COVID-19 vaccine hesitancy in pregnant women in Kilifi, Kenya
No full textCOVID-19 vaccines are safe and effective in pregnancy, but vaccine hesitancy limits uptake and effectiveness. This study explored COVID-19 vaccine hesitancy in pregnancy in Kilifi, coastal Kenya, to elicit reasons for vaccine hesitancy and acceptance, and to compile misconceptions around vaccination in pregnancy. Twenty-three in-depth interviews were conducted with pregnant women, mothers who had given birth in the previous 2 years and health workers (community health promoters, nurses, and supervisors). Data were analyzed using thematic template analysis based on the Vaccine Hesitancy Determinants Matrix. Concern about vaccine safety for the unborn baby was a major driver of hesitancy. Many pregnant women had limited knowledge of the potential benefits to the unborn baby, leading to postponing vaccination until after pregnancy. The initial government exclusion of pregnant women from vaccination led many to believe that vaccines were unsafe in pregnancy, long after the eligibility was revised. Aggressive promotion of the vaccine by the government was a source of mistrust and misconceptions. Integrating COVID-19 vaccination into routine antenatal care improved acceptance and development and dissemination of local guidelines boosted healthcare workers’ confidence in offering vaccines to pregnant women. Future rollouts of vaccines for pregnant women should consider vaccination within antenatal care clinics alongside other routine pregnancy vaccines to enhance vaccine acceptance.</p
Process evaluation of an integrated community-based intervention to improve family planning, sexual reproductive Health, and wellbeing among Syrian refugee women and girls in Lebanon during active conflict
Full text linkBackground: This study presents the first process evaluation of an integrated family planning, sexual reproductive health, and wellbeing community-based intervention among Syrian refugee women and girls in Lebanon. This intervention, known as the Self-Efficacy and Knowledge (SEEK) intervention, was developed by the World Health Organization as a low-resource and low-intensity initiative, and led by trained paraprofessionals (community health workers). Methods: The intervention was implemented between September and December 2024, a period marked by active conflict in Lebanon. A mixed-methods process evaluation was conducted, triangulating data from satisfaction surveys, field observations, and semi-structured interviews with participants, health workers, and program staff. Quantitative data were analyzed using SPSS, and qualitative data were analyzed using qualitative content analysis. Data collection tools assessed satisfaction, feasibility, fidelity to content, logistical and contextual barriers. Results: The evaluation revealed high participant satisfaction, with over 90% of participants rating session quality as good or excellent. Participants valued the program’s relevance, paraprofessionals community alignment, and the inclusion of interactive and visual aids. Paraprofessionals expressed satisfaction with the training and delivery process but, along with attending psychologists and midwives, reported the need for more soft-skills training and presentation skills. Logistical challenges included child care needs, transportation barriers, and the necessity of flexible scheduling. The war on Lebanon posed major implementation hurdles, requiring adaptive strategies such as remote coordination and increased reliance on leadership of local staff. Cultural and gender norms affected engagement, particularly around SRH content, with participants recommending greater involvement of men and household decision-makers. The presence of local women committees, research assistants, and field coordinators was key to maintaining trust, communication, and retention of participants. Conclusions: This evaluation demonstrates that SEEK is feasible, acceptable, and adaptable even in the context of active conflict. Its community-led design supported engagement and delivery, underscoring the importance of flexible and locally grounded implementation strategies in fragile settings.</p
The E205D mutation in CYP6P3 drives pyrethroid insecticide resistance in the African malaria mosquito vector Anopheles gambiae
No full textDeciphering the molecular drivers of insecticide resistance is paramount to extending the effectiveness of malaria vector control tools. Here, we demonstrate that a P450 haplotype spanning a Glu205→Asp (E205D) amino acid point mutation in the CYP6P3 gene drives pyrethroid insecticide resistance in the mosquito malaria vector Anopheles gambiae. Pooled whole-genome DNA sequencing data from A. gambiae mosquitoes detected a major P450-linked locus (CYP6 haplotype) on chromosome 2R adjacent to the locus encoding a sodium channel. In vitro metabolism assays with recombinantly expressed CYP6P3 protein revealed that the catalytic efficiency of the 205D variant for the pyrethroid insecticide permethrin was 3.7 times higher than that of the E205 variant. Similar findings were made for the related insecticide α-cypermethrin. Overexpression of the 205D variant in transgenic flies conferred higher resistance to pyrethroids compared with flies expressing the susceptible E205 variant. A DNA-based assay confirmed that the CYP6P3-E205D variant correlates with pyrethroid resistance in field mosquito populations [odds ratio (OR): 26.4; P < 0.0001] and reduces the efficacy of pyrethroid-only long-lasting insecticide bed nets. The homozygous resistance genotype of A. gambiae exhibited higher survival after exposure to the PermaNet 3.0 bed net compared with the susceptible SS genotype (OR: 6.1; P = 0.011). Furthermore, the CYP6P3-E205D variant together with the kdr target-site resistance mechanism exacerbated the loss of bed net efficacy. The 205D variant is predominant in West and Central Africa but less abundant or absent in East and South Africa, with signs of introgression with Anopheles coluzzii in Ghana.</p
Genetic Surveillance Reveals Differential Evolutionary Dynamic of Anopheles gambiae Under Contrasting Insecticidal Tools Used in Malaria Control
No full textMalaria, a febrile disease caused by the Plasmodium parasites and transmitted by mosquitoes, is a leading cause of mortality in children under 5 in endemic countries. The widespread deployment of insecticide-treated bed nets (ITNs) has significantly reduced malaria transmission, but rising levels of insecticide resistance threaten to halt the progress. Monitoring insecticide resistance is vital for effective vector control, particularly when deploying new tools. Understanding mosquito population responses to these interventions is crucial for guiding control programmes in making informed decisions about the selection, timing and geographic deployment of tools. This genomic study investigates the demographic and evolutionary consequences on the malaria vector Anopheles gambiae of deploying standard ITNs (containing only pyrethroids) and pyrethroid-PBO nets (containing pyrethroids plus the synergist piperonyl butoxide) during a clinical trial in Uganda. Despite substantial reductions in indoor mosquito densities in the clinical trial, estimates of nucleotide diversity (π) and linkage disequilibrium revealed no significant decline in effective population size, reflecting continued large population size even after effective control. Marked allele frequency shifts at resistance-associated loci indicated strong selection pressures driven by the interventions, with distinct selective dynamics between the two net types, highlighting alternative pyrethroid detoxification pathways in the presence of PBO. A duplication in the Cyp9k1 gene significantly increased in frequency in populations exposed to pyrethroid-only nets but decreased in populations exposed to PBO-treated nets, suggesting that selection for over-expression of this gene is removed when this resistance mechanism is impacted by PBO. An alternative potential detoxification mechanism was selected within a region of the 2La chromosomal inversion on chromosome 2 L, which encompasses the UDP-glucose 6-dehydrogenase gene. This variant consistently increased in frequency when exposed to PBO-treated nets. Additionally, pyrethroid-only nets selected for a novel locus on the X chromosome containing the diacylglycerol kinase gene, which is potentially linked to behavioural adaptations through its role in neurotransmission modulation. Our findings underscore the importance of genomic surveillance in vector control, revealing distinct evolutionary dynamics of insecticide resistance mechanisms in the presence of PBO. While ITNs remain effective, the persistence and evolution of resistance-associated alleles highlight the need for adaptive and dynamic resistance management strategies. By integrating high-resolution genomic data with epidemiological and entomological monitoring, this study offers actionable insights to sustain malaria control efforts amid the ongoing challenge of insecticide resistance.</p
Clinical morbidity of single or mixed schistosome species infection in two communities of southern Malawi
Full text linkAs part of a larger community-based epidemiological study entitled Hybridisation in Uro-Genital Schistosomiasis (HUGS), a parasite infection and clinical morbidity sub-study, implementing portable ultrasonography annually, was undertaken upon 701 participants from two communities in Mangochi and Nsanje Districts, southern Malawi. Our aim was to document the clinical morbidity a year after praziquantel treatment in those with previously proven human and/or zoonotic schistosomiasis, repeated a calendar year later after biannual praziquantel treatment. The median participant age was 12.0 years, with 293 (41.8%) having urinary Schistosoma haematobium egg-patent infections. Upon molecular analyses, these participants were co-infected with S. mansoni (29, 9.9%), S. mattheei (38, 13.0%), and six were infected with all three schistosome species occurring concurrently. A total of 166 participants (23.7%) had abnormal bladder wall thickness, 72 severely abnormal thickened bladder walls and 7 had bladder wall masses, among other abnormalities by ultrasonography. On the second annual follow-up, 203 participants were available (median age: 22.0 years), and of these, 27 (13.3%) presented with urinary S. haematobium egg-patent infections, with 2 (1.0%) having Schistosoma mansoni, 8 (3.9%) having Schistosoma mattheei and 2 with all species concurrently. Of these, only six participants (3.0%) had severely abnormal thickened bladder walls and other abnormalities. Overall, greater morbidity was observed in those with S. haematobium alone than in those with mixed species infections. 'This article is part of the Royal Society Science+ meeting issue 'Parasite evolution and impact in action: exploring the importance and control of hybrid schistosomes in Africa and beyond'.</p
Antigenicity of key hepatitis C virus E1E2 glycoprotein neutralizing sites is genotype independent
Full text linkThe development of an effective prophylactic hepatitis C virus (HCV) vaccine is a priority to achieve global elimination of the virus. Accurate assessment of the neutralizing breadth of antibodies induced by vaccines and a clear understanding of the antigenic differences between viral variants included in vaccines are both critical for vaccine development. Prior studies have indicated that HCV genotypes (gts) do not dictate the sensitivity of HCV envelope glycoprotein (E1E2) variants to neutralizing antibodies. However, most of these prior studies under-sampled variants from gts 2–6. Here, we selected a genetically diverse and representative panel of gt 2–6 E1E2 variants, used them to generate HCV pseudoparticles (HCVpp), and measured neutralization of these HCVpp by neutralizing antibodies and HCV-immune plasma from persons infected with gt 1–6 viruses. We found that neutralization results obtained with this gt 2–6 panel were remarkably similar to results obtained with a previously described, antigenically diverse, gt 1-predominant reference panel of 15 HCVpp. These data confirm that, even considering genetically diverse HCV variants across gt 1–6, E1E2 antigenicity is not dictated by gt, and that the previously published panel of 15 HCVpp represents neutralization of all HCV gts with reasonable accuracy.</p
Remote ischaemic conditioning improves outcomes of ischaemic stroke treated by endovascular thrombectomy: the SERIC-EVT trial
Full text linkBACKGROUND AND AIMS: Even after endovascular thrombectomy, more than half of patients with acute large vessel occlusion stroke do not achieve favourable outcomes. This study aimed to assess the efficacy and safety of remote ischaemic conditioning (RIC), a promising neuroprotective treatment, in patients with acute ischaemic stroke who received endovascular thrombectomy. METHODS: This participant-blinded, randomized controlled clinical trial was conducted at 25 hospitals. Patients were randomized 1:1 to either the RIC (cuff pressure, 200 mmHg; twice daily for 7 days) or sham RIC (60 mmHg; same procedure) groups. The primary outcome was the proportion of patients with a modified Rankin Scale score of 0-2 on Day 90. The primary safety outcome was the proportion of patients with haemorrhagic transformation within 7 days. RESULTS: In total, 498 participants were recruited. Ten patients (2.0%) were excluded because they did not receive any intervention. Thus, 488 participants (244 in the RIC group and 244 in the sham RIC group) were included in the modified intention-to-treat analysis. At 90 days, 61.1% of the patients in the RIC group and 48.9% in the sham RIC group achieved a modified Rankin Scale score of 0-2 (unadjusted risk ratio 1.25, 95% confidence interval 1.06-1.47; P = .009). The proportion of patients with haemorrhagic transformation was 37.7% and 35.2% in the RIC and sham RIC groups, respectively. CONCLUSIONS: Among patients with acute ischaemic stroke who underwent endovascular thrombectomy, intervention with RIC for 7 days, compared with sham RIC, resulted in an improved functional outcome at 90 days
Analysis of insecticide-treated bednet market dynamics between 2004–2021 and monetary value of additional bednet longevity
No full textBackgroundInsecticide-treated bednets (ITNs), a cornerstone of malaria prevention, are distributed via mass campaigns across Africa every three years, at huge cost to National Ministries of Health and development partners. While WHO sets global standards for ITNs as a public health commodity, they typically remain in use for less than the assumed three years, due to accumulation of damage, and retention times vary according to the product and use context. However, it is currently unclear whether ITN prices reflect their value in terms of physical durability.MethodsWe explored how various ITN product and market characteristics have influenced real ITN prices since 2004. We used ITN price and retention data across sub-Saharan Africa to calculate the country specific equivalent annual cost of ITNs and defined country-specific price thresholds that the market should be willing-to-pay to secure nets that would be retained and used for exactly three years or, separately for six months longer than current estimates suggest.FindingsThe ITN market has become less concentrated in the last two decades, but it remains dominated by a few large buyers and suppliers. ITN prices have decreased dramatically since 2010. Among individual sales, we found no evidence that increased durability is rewarded through higher price. The value for equivalent annual cost per person protected and the willingness-to-pay for a net that is retained for longer depends on baseline net price and is greater in countries with shorter existing ITN retention times.InterpretationSubstantial public health and efficiency gains could be realized if bednets were used for longer periods. However, achieving this requires changes in the market on both the supply and demand sides, including a shift towards value-based procurement. This approach would better incentivize manufacturers to innovate and invest in producing more durable nets by linking pricing to their long-term effectiveness. An explicit price threshold, along with improved information on net durability across different contexts, could help foster innovation and direct investment where it is most needed
One Health insights into local transmission of zoonotic Schistosoma mattheei in southern Malawi
Full text linkSchistosoma mattheei is a zoonotic schistosome species in central and southern Africa and is of increasing public health concern in southern Malawi. To gain insight into its local transmission, we investigated the biology of Schistosoma mattheei in southern Malawi, integrating epidemiological, environmental and genetic data within a One Health framework. Cattle, goats, humans and snails were surveyed, with DNA barcoding revealing nine mitochondrial S. mattheei haplotypes. Two haplotypes were shared across species, indicating cross-host transmission. Infected snails were detected year-round, with seasonal variation linked to vegetation cover (Normalized Difference Vegetation Index (NDVI)). Praziquantel (40 mg kg -1) treatment in selected cattle herds reduced infection prevalence over 12 weeks. These findings highlight the zoonotic potential of S. mattheei and the need for integrated control strategies. This article is part of the Royal Society Science+ meeting issue 'Parasite evolution and impact in action: exploring the importance and control of hybrid schistosomes in Africa and beyond'.</p
Emerging infectious diseases and pandemic responsiveness
No full textEmerging and re-emerging infectious diseases have been a constant threat throughout human history. An estimated 70% of emerging infectious diseases are thought to be zoonoses. Global urbanization and technological advances continue to change the way we interact with our environment, augmenting the risk of rapid spread, as seen with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) globally in 2020. Meanwhile multifaceted issues such as climate change, human–wildlife interactions, mis- and disinformation and geopolitical instability can impact the risk of an emerging infectious disease through shifting transmission dynamics and/or undermining of public health and medical countermeasures. Mis/disinformation and reduced public trust after the coronavirus disease (COVID-19) pandemic reduce engagement with medical countermeasures for endemic infections, while poor public and healthcare worker awareness around antimicrobial resistance increases the risk of a worsening ‘silent pandemic’. Greater collaboration is urgently required across ‘One Health’, by academic, private and political stakeholders, to reduce the social inequities of emerging infectious disease and build a resilient and responsive global security.</p