Impact of late rainy season indoor residual spraying on holoendemic malaria transmission: a cohort study in northern Zambia.

Background: Indoor residual spraying (IRS) is a malaria control strategy implemented before the rainy season. Nchelenge District, Zambia is a holoendemic setting where IRS has been conducted since 2008 with little impact on malaria incidence or parasite prevalence. Pre-rainy season IRS may not reduce the post-rainy season peak abundance of the major vector, Anopheles funestus.

Maintaining Immunizations for Vaccine-Preventable Diseases in a Changing World.

Immunization has saved an estimated 154 million lives over the past 50 years since the launch of the Essential (formerly Expanded) Program on Immunization in 1974, representing 6 lives saved every minute, every year, for 50 years. But achieving and maintaining high immunization coverage have required sustained political and public commitment, financial resources, strong partnerships, research and innovation, and communication and advocacy. New and evolving challenges to maintaining high immunization coverage have emerged alongside long-standing stubborn obstacles.

Measles and rubella seroprevalence in adults using residual blood samples from health facilities and household serosurveys in Palghar District, Maharashtra, India, 2018 - 2019.

Residual blood specimens collected at health facilities may be a source of samples for serosurveys of adults, a population often neglected in community-based serosurveys. Anonymized residual blood specimens were collected from individuals 15 - 49 years of age attending two sub-district hospitals in Palghar District, Maharashtra, from November 2018 to March 2019. Specimens also were collected from women 15 - 49 years of age enrolled in a cross-sectional, community-based serosurvey representative at the district level that was conducted 2 - 7 months after the residual specimen collection.

Report from the World Health Organization's immunization and vaccines-related implementation research advisory committee (IVIR-AC) meeting, virtual gathering, 10-13 September 2024.

The Immunization and Vaccines-related Implementation Research Advisory Committee (IVIR-AC) is the primary advisory body of the World Health Organization conducting independent reviews of immunization-related implementation research, with a primary focus on transmission and economic modeling analyses that estimate the value and impact of vaccines. From 10 to 13th September 2024, IVIR-AC convened virtually for its second of two semi-annual meetings to provide feedback and recommendations across six sessions including: pneumococcal vaccination strategies that rely on indirect protection; vaccine impact modeling for chikungunya; The Lancet Commission on strengthening the use of epidemiological modeling of emerging and pandemic infectious diseases; methods for immunization coverage estimation; setting immunization research priorities in the South-East Asian Region; and modeling evidence related to typhoid conjugate vaccine schedules. This report summarizes the sessions, proceedings, and recommendations from that meeting.

Clinicopathologic Features of Oral Verrucous Carcinoma: A Systematic Review and Meta-Analysis.

Objective: To further characterize the clinicopathologic features of oral verrucous carcinoma.

Methods: In accordance with PRISMA guidelines, a systematic review of the Medline, Web of Science, Embase, and Cochrane databases was performed in search of articles evaluating clinicopathologic features of oral verrucous carcinoma. Primary outcomes of interest included tumor subsites, T-staging, rates of cervical lymph node metastases, rates of distant metastases, 5-year survival (overall, disease-free, or disease-specific), and recurrence rates.

Application of a new highly multiplexed amplicon sequencing tool to evaluate antimalarial resistance and relatedness in individual and pooled samples from Dschang, Cameroon.

Background: Resistance to antimalarial drugs remains a major obstacle to malaria elimination. Multiplexed, targeted amplicon sequencing is being adopted for surveilling resistance and dissecting the genetics of complex malaria infections. Moreover, genotyping of parasites and detection of molecular markers drug resistance in resource-limited regions requires open-source protocols for processing samples, using accessible reagents, and rapid methods for processing numerous samples including pooled sequencing.

Report from the World Health Organization's immunization and vaccines-related implementation research advisory committee (IVIR-AC) ad hoc meeting, 28 June - 1 July 2024.

The World Health Organization's Immunization and Vaccines-related Implementation Research Advisory Committee (IVIR-AC) serves to independently review and evaluate vaccine-related research to maximize the potential impact of vaccination programs. From 28 June - 1 July 2024, IVIR-AC was convened for an ad hoc meeting to discuss new evidence on criteria for rubella vaccine introduction and the risk of congenital rubella syndrome. This report summarizes background information on rubella virus transmission and the burden of congenital rubella syndrome, meeting structure and presentations, proceedings, and recommendations.

Challenges and Approaches to Establishing Multi-Pathogen Serosurveillance: Findings from the 2023 Serosurveillance Summit.

Multiplex-based serological surveillance is a valuable but underutilized tool to understand gaps in population-level exposure, susceptibility, and immunity to infectious diseases. Assays for which blood samples can be tested for antibodies against several pathogens simultaneously, such as multiplex bead immunoassays, can more efficiently integrate public health surveillance in low- and middle-income countries. On March 7-8, 2023 a group of experts representing research institutions, multilateral organizations, private industry, and country partners met to discuss experiences, identify challenges and solutions, and create a community of practice for integrated, multi-pathogen serosurveillance using multiplex bead assay technologies.

Adjusting mobile phone data to account for children's travel and the impact on measles dynamics in Zambia.

Models of measles transmission can be used to identify areas of high risk to tailor immunization strategies. Estimates of spatial connectivity can be derived from data such as mobile phone records, however it is not clear how this maps to the movement of children who are more likely to be infected. Using travel surveys across two districts in Zambia and national mobile phone data, we compared estimates of out-of-district travel for the population captured in the mobile phone data and child-specific travel from travel surveys.

National genomic profiling of antimalarial resistance in Zambian children participating in the 2018 Malaria Indicator Survey.

The emergence of antimalarial drug resistance is a major threat to malaria control and elimination. Using whole genome sequencing of 282 samples collected during the 2018 Zambia National Malaria Indicator Survey, we determined the prevalence and spatial distribution of known and candidate antimalarial drug resistance mutations. High levels of genotypic resistance were found across Zambia to pyrimethamine, with over 94% (n=266) of samples having the triple mutant (N51, C59, and S108), and sulfadoxine, with over 84% (n=238) having the double mutant (A437 and K540).

Possible Paths to Measles Eradication: Conceptual Frameworks, Strategies, and Tactics.

Measles elimination refers to the interruption of measles virus transmission in a defined geographic area (e.g., country or region) for 12 months or more, and measles eradication refers to the global interruption of measles virus transmission.

What's going on with measles?

Measles is a highly transmissible systemic viral infection associated with substantial mortality primarily due to secondary infections. Measles induces lifelong immunity to reinfection but loss of immunity to other pathogens. An attenuated live virus vaccine is highly effective, but lapses in delivery have resulted in increasing cases worldwide.

Diversity and selection analyses identify transmission-blocking antigens as the optimal vaccine candidates in Plasmodium falciparum.

Background: A highly effective vaccine for malaria remains an elusive target, at least in part due to the under-appreciated natural parasite variation. This study aimed to investigate genetic and structural variation, and immune selection of leading malaria vaccine candidates across the Plasmodium falciparum's life cycle.

Methods: We analysed 325 P.

Feasibility and acceptability of collecting dried blood spots (DBS) from children after vaccination during supplementary immunization activities to estimate measles and rubella seroprevalence.

Nested serosurveys within routine service delivery platforms such as planned supplemental immunization activities (SIAs) provide an opportunity to collect information that can be used to answer valuable questions on the effectiveness and efficiency of the delivery model to inform future activities. However, integrating research data collection in SIAs is rarely done due to concerns it will negatively impact the program. We conducted a serosurvey nested within the November 2020 measles-rubella SIA integrated with the Child Health Week activities in Zambia to evaluate this approach.

Temporal genomic analysis of reveals increased prevalence of mutations associated with delayed clearance following treatment with artemisinin-lumefantrine in Choma District, Southern Province, Zambia.

The emergence of antimalarial drug resistance is an impediment to malaria control and elimination in Africa. Analysis of temporal trends in molecular markers of resistance is critical to inform policy makers and guide malaria treatment guidelines. In a low and seasonal transmission region of southern Zambia, we successfully genotyped 85.

COVID-19 vaccine hesitancy, trust, and communication in Sarlahi District, Nepal.

Background: Strategies to increase COVID-19 vaccine coverage require an understanding of the extent and drivers of vaccine hesitancy and trust in government related to COVID-19 vaccine programs, especially in low-resource communities.

Methods: We conducted a cross-sectional household survey post-COVID-19 vaccine introduction among adults (n = 362) in four municipalities in Sarlahi District, Nepal from August to December 2022. The survey included modules on participant demographics and socioeconomic factors and vaccine hesitancy, information seeking, and trust in authorities related to COVID-19 vaccination.

Food and water insecurity in households of children and adolescents living with HIV and receiving care in a rural Zambian hospital: A mixed-methods study.

Approximately 62,000 Zambian children are living with HIV. HIV care and treatment is generally more limited in rural areas, where a heavy reliance on rain-fed subsistence agriculture also places households at risk of food and water insecurity. We nested a mixed methods study with an explanatory sequential design in a clinical cohort of children and adolescents living with HIV (CHIV) in rural Zambia.

Proteomic approaches for protein kinase substrate identification in Apicomplexa.

Apicomplexa is a phylum of protist parasites, notable for causing life-threatening diseases including malaria, toxoplasmosis, cryptosporidiosis, and babesiosis. Apicomplexan pathogenesis is generally a function of lytic replication, dissemination, persistence, host cell modification, and immune subversion. Decades of research have revealed essential roles for apicomplexan protein kinases in establishing infections and promoting pathogenesis.

Modeling the Cost of Vaccinating a Measles Zero-Dose Child in Zambia Using Three Vaccination Strategies.

Countries with moderate to high measles-containing vaccine coverage face challenges in reaching the remaining measles zero-dose children. There is growing interest in targeted vaccination activities to reach these children. We developed a framework for prioritizing districts for targeted measles and rubella supplementary immunization activities (SIAs) for Zambia in 2020, incorporating the use of the WHO's Measles Risk Assessment Tool (MRAT) and serosurveys.

Malaria Transmission at The Zimbabwe-Mozambique Border: An Observational Study of Parasitemia by Travel History and Household Location.

Cross-border human population movement contributes to malaria transmission in border regions, impeding national elimination. However, its impact in low-to-moderate transmission settings is not well characterized. This community-based study in Mutasa District, Zimbabwe, estimated the association of parasite prevalence with self-reported overnight travel to Mozambique and household distance to the border from 2012-2020.