ABSTRACT
BACKGROUND: Globally, malaria continues to pose a major health challenge, with approximately 247 million cases of the illness and 627,000 deaths reported in 2021. However, the threat is particularly pronounced in sub-Saharan African countries, where pregnant women and children under the age of five face heightened vulnerability to the disease. As a result, the imperative to develop malaria vaccines especially for these vulnerable populations, remains crucial in the pursuit of malaria eradication. However, despite decades of research, effective vaccine development faces technical challenges, including the rapid spread of drug-resistant parasite strains, the complex parasite lifecycle, the development of liver hypnozoites with potential for relapse, and evasion of the host immune system. This review aims to discuss the different malaria vaccine candidates in the pipeline, highlighting different approaches used for adjuvating these candidates, their benefits, and outcomes, and summarizing the progress of these vaccine candidates under development. METHOD: A comprehensive web-based search for peer-reviewed journal articles published in SCOPUS, MEDLINE (via PubMed), Science Direct, WHO, and Advanced Google Scholar databases was conducted from 1990 to May 2022. Context-specific keywords such as "Malaria", "Malaria Vaccine", "Malaria Vaccine Candidates", "Vaccine Development", "Vaccine Safety", "Clinical Trials", "mRNA Vaccines", "Viral Vector Vaccines", "Protein-based Vaccines", "Subunit Vaccines", "Vaccine Adjuvants", "Vaccine-induced Immune Responses", and "Immunogenicity" were emphatically considered. Articles not directly related to malaria vaccine candidates in preclinical and clinical stages of development were excluded. RESULTS: Various approaches have been studied for malaria vaccine development, targeting different parasite lifecycle stages, including the pre-erythrocytic, erythrocytic, and sexual stages. The RTS, S/AS01 vaccine, the first human parasite vaccine reaching WHO-listed authority maturity level 4, has demonstrated efficacy in preventing clinical malaria in African children. However, progress was slow in introducing other safe, and feasible malaria vaccines through clinical trials . Recent studies highlight the potential effectiveness of combining pre-erythrocytic and blood-stage vaccines, along with the advantages of mRNA vaccines for prophylaxis and treatment, and nonstructural vaccines for large-scale production. CONCLUSION: Malaria vaccine candidates targeting different lifecycle stages of the parasite range from chemoprophylaxis vaccination to cross-species immune protection. The use of a multi-antigen, multi-stage combinational vaccine is therefore essential in the context of global health. This demands careful understanding and critical consideration of the long-term multi-faceted interplay of immune interference, co-dominance, complementary immune response, molecular targets, and adjuvants affecting the overall vaccine-induced immune response. Despite challenges, advancements in clinical trials and vaccination technology offer promising possibilities for novel approaches in malaria vaccine development.
ABSTRACT
INTRODUCTION: Nigeria is a low-middle income country located in sub-Saharan Africa. Although cancer burden has continued to increase over time, there is a lack of pharmacists who specialize in oncology providing pharmaceutical care. The objectives of this study were to understand the perception of hematology/oncology pharmacy practice in Nigeria as well as the unmet education needs. METHOD: This is a cross-sectional survey conducted in December 2023. Pharmacists who were active members of various pharmacy organizations in Nigeria were invited to complete the survey. The survey focused on the perceptions of training needs in oncology pharmacy, current challenges and opportunities, as well as resources and support needed. Descriptive statistics were utilized for the data analysis. RESULTS: Of the 263 responders, the largest group fell between 25 and 34 years old (35%), over half received a Bachelor of Pharmacy as their highest degree (53%), and majority did not receive any oncology pharmacy training as part of their education (73%). Many respondents strongly agreed that pharmacists in Nigeria need specialized training to better serve cancer patients (79%). Cancer therapeutics and chemotherapy pharmacology were more prioritized compared to other training needs (mean (SD): 2.63(1.95) and 2.69(1.64), respectively). The main challenge that respondents faced was a lack of relevant skills and knowledge in oncology pharmacy (mean (SD): 2.23(1.53)). More than a fourth of the respondents were aware about the board certification process (28.8%), citing overcoming the cost barrier as the main obstacle for taking the board examination (mean (SD): 1.92 (1.38)). Respondents preferred online courses and onsite specialty training (75%) as the mode of training to address unmet needs. CONCLUSION: Despite the challenges and unmet education needs in hematology/oncology clinical practice, Nigerian pharmacists are very willing to expand their knowledge and improve their skills in patient care. The findings of this study can inform policy makers, healthcare administrators, and pharmacy educators in developing global partnerships among pharmacy organizations which employ targeted strategies like sponsorships to address such unmet needs.
ABSTRACT
Background: In the era of insecticides and anti-malarial drug resistance, gene drive technology holds considerable promise for malaria control. Gene drive technology deploys genetic modifications into mosquito populations to impede their ability to transmit the malaria parasite. This can be either through the disruption of an essential mosquito gene or the association of gene drive with a desirable effector gene. CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is a gene editing tool that precisely modifies mosquito vector DNA sequences and curtails the rate of pathogen transmission.Methods: A comprehensive search was conducted in the SCOPUS and MEDLINE databases (via PubMed) until October 2023. The keywords used were related to the principles and mechanisms of gene drive technology, its advantages, and disadvantages, and its ethical and regulatory considerations in sustainable malaria eradication.Results: The development of gene drive enables the preferential inheritance of specific genes in targeted mosquitoes, potentially obstructing the transmission of the Plasmodium parasite. This technology was also studied for the control of other vector-borne diseases such as dengue and chikungunya viruses. Despite its experimental superiority over other traditional methods such as insecticide-treated nets and insecticide sprays, the long-term dynamic interplay of mutation and resistance poses challenges for gene drive efficiency in sustainable malaria control.Conclusions: This commentary elucidates the underlying mechanisms and principles of gene drive technology, underscoring its promise and challenges as a novel strategy to curtail malaria prevalence. Although the release of such genetically modified mosquitoes into the natural environment would result in the eradication of the locally targeted species of mosquitoes, the complete eradication of the entire species remains questionable. Thus, the practical application raises significant ethical and regulatory concerns for further research and risk assessment, including the risk of gene drive spreading to nontarget species in the wider theatre of biodiverse species.