The Effect of Malaria on Responses to Unrelated Vaccines in Animals and Humans: A Systematic Review and Meta-Analysis.

Vaccine efficacy varies globally, often showing reduced immune responses in low- and middle-income countries, possibly due to the immunomodulatory effects of parasitic infections like malaria. This systematic review evaluates the impact of malaria on immune responses to unrelated vaccines in humans and animals. We systematically searched five databases-MEDLINE, Web of Science, Global Health, Scopus and Embase-up to 5th December 2023.

Schistosome and malaria exposure and urban-rural differences in vaccine responses in Uganda: a causal mediation analysis using data from three linked randomised controlled trials.

Background: Vaccine immunogenicity and effectiveness vary geographically. Chronic immunomodulating parasitic infections including schistosomes and malaria have been hypothesised to be mediators of geographical variations.

Methods: We compared vaccine-specific immune responses between three Ugandan settings (schistosome-endemic rural, malaria-endemic rural, and urban) and did causal mediation analysis to assess the role of Schistosoma mansoni and malaria exposure in observed differences.

The effect of BCG revaccination on the response to unrelated vaccines in urban Ugandan adolescents (POPVAC C): an open-label, randomised controlled trial.

Background: Immune responses induced by several important vaccines differ between populations, with reduced responses in low-income and rural settings compared with high-income and urban settings. BCG immunisation boosts immune responses to some unrelated vaccines in high-income populations. We aimed to test the hypothesis that BCG revaccination can enhance responses to unrelated vaccines in Ugandan schoolchildren.

The effect of intermittent preventive treatment for malaria with dihydroartemisinin-piperaquine on vaccine-specific responses among schoolchildren in rural Uganda (POPVAC B): a double-blind, randomised controlled trial.

Background: Several important vaccines differ in immunogenicity and efficacy between populations. We hypothesised that malaria suppresses responses to unrelated vaccines and that this effect can be reversed-at least partially-by monthly malaria intermittent preventive treatment (IPT) in high-transmission settings.

Methods: We conducted an individually randomised, double-blind, placebo-controlled trial of the effect of malaria IPT with dihydroartemisinin-piperaquine on vaccine responses among schoolchildren aged 9-17 years in Jinja district, Uganda.

The effect of intensive praziquantel administration on vaccine-specific responses among schoolchildren in Ugandan schistosomiasis-endemic islands (POPVAC A): an open-label, randomised controlled trial.

Background: Vaccine responses differ between populations and are often impaired in rural and low-income settings. The reasons for this are not fully understood, but observational data suggest that the immunomodulating effects of parasitic helminths might contribute. We hypothesised that Schistosoma mansoni infection suppresses responses to unrelated vaccines, and that suppression could be reversed-at least in part-by intensive praziquantel administration.

NIHR Global Health Research Group on Vaccines for vulnerable people in Africa (VAnguard): Concept and Launch event report.

Background: Vaccination is an important public health intervention, but not everyone benefits equally. Biological, social and structural factors render some communities vulnerable and unable to secure optimal health benefits from vaccination programmes. This drives health inequity and undermines wider vaccine impact by allowing the persistence of non-immune communities as foci for recurrent disease outbreaks.

The effect of helminth infection on vaccine responses in humans and animal models: A systematic review and meta-analysis.

Vaccination has potential to eliminate infectious diseases. However, parasitic infections such as helminths may hinder vaccines from providing optimal protection. We reviewed existing literature on the effects of helminth infections and their treatment on vaccine responses in humans and animals.

Impact of BCG revaccination on the response to unrelated vaccines in a Ugandan adolescent birth cohort: randomised controlled trial protocol C for the 'POPulation differences in VACcine responses' (POPVAC) programme.

Introduction: There is evidence that BCG immunisation may protect against unrelated infectious illnesses. This has led to the postulation that administering BCG before unrelated vaccines may enhance responses to these vaccines. This might also model effects of BCG on unrelated infections.

Effect of intermittent preventive treatment for malaria with dihydroartemisinin-piperaquine on immune responses to vaccines among rural Ugandan adolescents: randomised controlled trial protocol B for the 'ulation differences in cine responses' (POPVAC) programme.

Introduction: Drivers of lower vaccine efficacy and impaired vaccine-specific immune responses in low-income versus high-income countries, and in rural compared with urban settings, are not fully elucidated. Repeated exposure to and immunomodulation by parasite infections may be important. We focus on malaria, aiming to determine whether there are reversible effects of malaria infection on vaccine responses.

Effect of intensive treatment for schistosomiasis on immune responses to vaccines among rural Ugandan island adolescents: randomised controlled trial protocol A for the 'ulation differences in cine responses' (POPVAC) programme.

Introduction: Several licensed and investigational vaccines have lower efficacy, and induce impaired immune responses, in low-income versus high-income countries and in rural, versus urban, settings. Understanding these population differences is essential to optimising vaccine effectiveness in the tropics. We suggest that repeated exposure to and immunomodulation by chronic helminth infections partly explains population differences in vaccine response.

Population differences in vaccine responses (POPVAC): scientific rationale and cross-cutting analyses for three linked, randomised controlled trials assessing the role, reversibility and mediators of immunomodulation by chronic infections in the tropics.

Introduction: Vaccine-specific immune responses vary between populations and are often impaired in low income, rural settings. Drivers of these differences are not fully elucidated, hampering identification of strategies for optimising vaccine effectiveness. We hypothesise that urban-rural (and regional and international) differences in vaccine responses are mediated to an important extent by differential exposure to chronic infections, particularly parasitic infections.

Design and Evaluation of a Novel Mobile Phone Application to Improve Palliative Home-Care in Resource-Limited Settings.

Context: Mobile health (mHealth) provides an opportunity to use internet coverage in low- and middle-income countries to improve palliative care access and quality.

Objectives: This study aimed to design a mobile phone application (app) to enable or improve communication between family caregivers, community caregivers, and palliative care teams; to evaluate its acceptability, processes, and mechanisms of action; and to propose refinements.

Methods: A codesign process entailed collaboration between a Project Advisory Group and collaborators in India, Uganda, and Zimbabwe.

A systematic review and meta-analysis to assess the association between urogenital schistosomiasis and HIV/AIDS infection.

Background: Urogenital schistosomiasis and HIV/AIDS infections are widespread in sub-Saharan Africa (SSA) leading to substantial morbidity and mortality. The co-occurrence of both diseases has led to the possible hypothesis that urogenital schistosomiasis leads to increased risk of acquiring HIV infection. However, the available evidence concerning this association is inconsistent.