Live, Attenuated Cholera Vaccine: A Long RandD Journey's Light Ahead

| Posted in: Science Health Sciences

Journal name: The Malaysian Journal of Medical Sciences
Original article title: Live, Genetically Attenuated, Cold-Chain-Free Cholera Vaccine—A Research and Development Journey: Light at the End of a Long Tunnel
The Malaysian Journal of Medical Sciences (MJMS) is a peer-reviewed, open-access journal published online at least six times a year. It covers all aspects of medical sciences and prioritizes high-quality research.
This page presents a generated summary with additional references; See source (below) for actual content.

Original source:

This page is merely a summary which is automatically generated hence you should visit the source to read the original article which includes the author, publication date, notes and references.

Author:

Manickam RAVICHANDRAN, Hui Xian TEW, Guruswamy PRABHAKARAN, Subramani PARASURAMAN, Mohd Nor NORAZMI


The Malaysian Journal of Medical Sciences:

(A peer-reviewed, open-access journal)

Full text available for: Live, Genetically Attenuated, Cold-Chain-Free Cholera Vaccine—A Research and Development Journey: Light at the End of a Long Tunnel

Year: 2022 | Doi: 10.21315/mjms2022.29.2.1

Copyright (license): CC BY 4.0


Download the PDF file of the original publication


Summary of article contents:

Introduction

Cholera, a severe diarrheal disease caused by the bacterium Vibrio cholerae (both O1 and O139 strains), remains a significant public health concern. Traditionally, vaccination against cholera involves killed, multiple-dose oral vaccines requiring cold-chain supply, which complicates their distribution, particularly in low-resourced regions. The pursuit of a live, single-dose, cold-chain-free cholera vaccine began in 2000 at Universiti Sains Malaysia. The development process included the isolation of the hemA gene, creating several vaccine candidates, and the eventual refinement of a promising candidate known as VCUSM14P, which demonstrates excellent immunogenicity and protective efficacy against cholera.

Summary of One Important Concept: Development of VCUSM14P

VCUSM14P represents a significant advancement in cholera vaccine development. Initially constructed by mutating the hemA gene to create an ALA auxotrophic strain, the vaccine underwent various modifications to enhance its safety and immunogenicity. In particular, VCUSM14P retained the intact cholera toxin B subunit, acting as a mucosal adjuvant, thereby amplifying immune responses without inducing significant reactogenicity. Its efficacy was demonstrated through various preclinical trials showing it can effectively colonize and elicit a robust immune response in animal models, providing 100% protection against challenge with virulent strains. Furthermore, VCUSM14P's cold-chain-free formulation is stable at room temperature for extended periods, promising significant logistical advantages for mass vaccination campaigns.

Conclusion

The development of VCUSM14P is a promising step forward in the fight against cholera, particularly in underserved populations burdened by this disease. While advancements have been made, there are still critical challenges to face, particularly regarding regulatory approvals and clinical trials needed for vaccine rollout. The project has highlighted the importance of addressing logistical concerns in vaccine distribution, especially in resource-limited settings. As the research team continues to seek necessary funding and support, VCUSM14P could play a pivotal role in future cholera outbreaks, potentially revolutionizing vaccination strategies and enabling effective responses in regions most affected by cholera.

FAQ section (important questions/answers):

What is cholera and how is it transmitted?

Cholera is a diarrheal disease caused by the bacterium Vibrio cholerae. It is transmitted through consuming contaminated food and drinking water, leading to severe dehydration if left untreated.

What are the characteristics of the new cholera vaccine?

The new cholera vaccine is a live attenuated, cold-chain-free formulation, requiring only a single dose. It mimics natural infection, is non-reactogenic, immunogenic, and stable at room temperature, facilitating easier distribution and lower costs.

What were the developmental stages of the VCUSM14P vaccine?

The VCUSM14P vaccine underwent several developmental stages, including gene mutation, reactogenicity reduction, toxicity evaluations, and formulation development, leading to its use as a cholera vaccine candidate with promising immunity results.

What are the future plans for the cholera vaccine?

The next stages include meeting regulatory requirements for clinical trials, ensuring safety and efficacy, and conducting trials in regions most affected by cholera, which will require support from governments and industries.

Glossary definitions and references:

Scientific and Ayurvedic Glossary list for “Live, Attenuated Cholera Vaccine: A Long RandD Journey's Light Ahead”. This list explains important keywords that occur in this article and links it to the glossary for a better understanding of that concept in the context of Ayurveda and other topics.

1) Toxicity:
Toxicity in the context of vaccine development refers to the potential harmful effects of a vaccine on biological systems. Understanding toxicity is crucial to ensure that the vaccine is safe for administration, especially in vulnerable populations. The text outlines various toxicity evaluations conducted during the development of the cholera vaccine.

2) Disease:
A disease is a pathological condition of a bodily part, resulting from various causes like infection. Cholera, highlighted in the text, is caused by Vibrio cholerae and is a significant public health issue. Effective disease management often depends on vaccination, sanitation, and access to clean water.

3) Study (Studying):
Studying refers to the act of investigating or examining a subject in depth. The text outlines an extensive research journey focused on studying cholera and vaccine responses, emphasizing the scientific rigor required in the development of effective public health interventions.

4) Science (Scientific):
Science refers to the systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe. The development of the cholera vaccine demonstrates the application of scientific principles in microbiology, genetics, and immunology, crucial for disease control and prevention.

5) Animal:
In the context of vaccine development, animals are often used in preclinical studies to evaluate safety and efficacy. The text cites studies using rabbits and rats to assess the reactogenicity and protective efficacy of the new cholera vaccine candidate, providing insights before human trials.

6) Mutation:
Mutation refers to a change in the DNA sequence that can impact an organism's phenotype. The text describes the intentional mutations made to the V. cholerae genome to create an attenuated strain that is less harmful, which is essential for developing a safer vaccine.

7) Water:
Water is a critical resource for life and plays a vital role in disease transmission, especially for waterborne pathogens like V. cholerae. The text emphasizes the importance of clean drinking water in controlling cholera outbreaks, reflecting its public health significance in combating the disease.

8) Table:
In scientific texts, 'table' often refers to a systematic arrangement of data. However, in the given text, no direct table is mentioned. If there were a table, it would likely summarize key findings or parameters regarding vaccine efficacy, safety, and the dosing regimen essential for clarity.

9) Tuberculosis:
Tuberculosis (TB) is a bacterial infection that primarily affects the lungs but can impact other parts of the body. The text mentions that the cholera vaccine's formulation may serve as a delivery vehicle for TB vaccines, highlighting its potential to address multiple infectious diseases.

10) Developing:
Developing refers to the process of creating or improving something. In this context, it signifies both the ongoing work to create a cholera vaccine and its implications for public health. The text outlines the step-by-step approach taken by researchers over two decades to develop this crucial vaccine.

11) Bengal (Bemgal):
Bengal is a region that has historically been associated with outbreaks of cholera, primarily caused by specific strains of V. cholerae. The text references the O139 serogroup's emergence in Bengal, emphasizing the geographical relevance of this area in understanding cholera's epidemiology and driving vaccine development.

12) Death:
Death, particularly in the context of cholera, is a severe outcome of the disease due to dehydration and other complications. The text highlights the case-fatality rates associated with cholera, underlining the urgency for effective vaccines to prevent fatalities in affected populations.

13) Hema (Heman):
Hema is likely a shortened reference to 'hemA,' a gene involved in the biosynthesis of 5-aminolaevulinic acid (ALA). The text discusses the modification of this gene in V. cholerae strains to create an auxotrophic vaccine candidate, highlighting its significance in the vaccine development process.

14) Post:
Post refers to the period after an event has occurred. In the context of the text, it often pertains to immunological responses measured in test subjects following vaccination. These post-vaccination responses are critical for establishing the vaccine's efficacy in inducing a protective immune response.

15) Transmission:
Transmission involves the spread of a pathogen from one host to another or from an environmental source to a host. The text discusses cholera transmission modes, emphasizing the necessity of vaccine development to interrupt the cycle of infection and protect vulnerable populations.

16) Accumulation (Accumulating, Accumulate):
Accumulation refers to the build-up of substances, often in a biological context. The text mentions fluid accumulation as a response to cholera infection. Understanding this process helps assess the pathogenicity of the cholera strains and the efficacy of the developed vaccine in preventing such outcomes.

17) Paracuraman:
Parasuraman appears to be a name likely connected to one of the researchers involved in the vaccine study. The text acknowledges multiple contributors to the research journey, indicating teamwork's role in advancing scientific understanding and developing the cholera vaccine.

18) Family:
Family may refer to groups of related organisms or familial relationships among researchers. In the context of cholera, families are impacted by outbreaks, highlighting the importance of public health measures to protect communities. Also implied is the sense of teamwork within research endeavors.

19) Indian:
Indian refers to the nationality associated with the country of India, where significant cholera outbreaks have historically occurred. The text references how cholera's emergence and impact in Indian communities underscore the relevance of developing effective vaccines to combat this endemic disease.

20) Sign:
A sign often indicates an observable effect or symptom of a disease. In the context of the text, signs may relate to the clinical observations recorded during vaccine trials, crucial for determining the reactogenicity and efficacy of the cholera vaccine under development.

21) Chan:
Chan likely refers to one of the contributing authors or researchers involved in the cholera vaccine study. Individual researchers' contributions are crucial in interdisciplinary projects like this, where diverse expertise helps drive scientific innovation toward public health solutions.

22) Education:
Education emphasizes the importance of learning and knowledge dissemination, particularly in scientific research. The text's findings can contribute to global education around cholera prevention, highlighting public health education's role in combating vaccine-preventable diseases in vulnerable communities.

23) Medicine:
Medicine is a field dedicated to the diagnosis, treatment, and prevention of disease. The text's focus on vaccine development exemplifies medicine's pivotal role in public health, particularly in creating effective interventions against infectious diseases like cholera.

24) Entering:
Entering signifies the beginning of a phase or stage. In the text, it suggests the transition into new avenues of research or clinical development for the cholera vaccine, pointing to the ongoing progress and challenges associated with bringing the vaccine to the market.

25) Chennai:
Chennai is a major city in India, where the first O139 strain of V. cholerae was reported. Its historical significance in cholera outbreaks underscores the necessity for local vaccine development initiatives, impacting both regional and global public health strategies against cholera.

26) Meeting:
Meeting typically denotes a gathering for discussion or decision-making. This could imply discussions within research teams about vaccine strategies or regulatory meetings aimed at advancing the cholera vaccine's clinical trial stages, essential for collaboration and decision-making.

27) Surface:
Surface often refers to the outer layer of cells or tissues. In the context of the text, it suggests examining the mucosal layer of intestines where vaccine-induced bacteria may reside, emphasizing the importance of understanding interactions between vaccines and host tissues.

28) Reason:
Reason involves logical explanations for actions or phenomena. In the context of vaccine development, it could refer to the rationale behind specific research choices, such as vaccine strain modifications intended to enhance safety and immunogenicity as outlined in the text.

29) Killing (Killed):
Killed can refer to 'killed' vaccines, which consist of inactivated pathogens. The text contrasts these with live attenuated vaccines, underscoring the benefits of a cold-chain-free, live vaccine approach for cholera, which may be more effective and administratively easier to handle.

30) India:
India is a country significantly affected by cholera outbreaks due to its population density and sanitation challenges. The text highlights the need for effective vaccines in regions like India, where cholera remains a public health concern needing urgent attention and intervention.

31) Trade:
Trade refers to the exchange of goods and services, which can be negatively impacted by disease outbreaks. The text notes that cholera's stigma affects trade and tourism, emphasizing how health and economic sectors are interconnected, requiring robust health solutions like effective vaccines.

32) Blood:
Blood is vital for circulatory functions, but its mention in the context of vaccine development can relate to immunological assessments. The text may imply measuring specific immune responses in the bloodstream after vaccination, critical for evaluating the vaccine's efficacy in eliciting immunity.

33) Trina (Trna, Tri-na):
tRNA (transfer RNA) plays a crucial role in protein synthesis by transporting amino acids to ribosomes during translation. In the context of genetic modifications discussed in the text, understanding tRNA’s function would support the overall comprehension of mutations made in vaccine development.

34) Food:
Food is a primary medium for transmitting cholera, highlighting the importance of sanitation and safe eating practices. The text underscores cholera’s transmission routes via contaminated food and water, indicating a need for effective vaccines to prevent outbreaks caused by foodborne pathogens.

35) Ting:
Ting could reference one of the contributors to the research, demonstrating the interdisciplinary nature of the vaccine development project. Collaboration among various researchers reflects the collective effort needed to advance scientific understanding and tackle complex public health challenges.

36) Pur:
Poor often refers to populations lacking adequate resources, making them vulnerable to diseases like cholera. The text emphasizes the importance of developing cost-effective vaccines to ensure accessibility for poor communities, aligning with global health equity goals and improving health outcomes.

Other Health Sciences Concepts:

[back to top]

Discover the significance of concepts within the article: ‘Live, Attenuated Cholera Vaccine: A Long RandD Journey's Light Ahead’. Further sources in the context of Health Sciences might help you critically compare this page with similair documents:

Drinking water, Contaminated food, Clean drinking water, Clinical trial, World Health Organization, Good Manufacturing Practice, Room temperature, Good Laboratory Practice, Case fatality rate, Regulatory compliance, Clinical development, Immunogenicity, Mucosal immune response, Toxicity evaluation, Vaccine formulation, Antibody Titre, Homologous recombination, Rabbit model, Regulatory requirement, Protective Efficacy, Vibrio cholerae, Oral cholera vaccine, DNA vaccine, Enterotoxigenic E. coli, Repeated Dose Toxicity, Funding agencies, Sprague Dawley (SD) rats, Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), Mucosal Route, Sprague Dawley rat, Mucosal adjuvant, Diarrheal disease, Live attenuated, Research success, Immunogenicity and protective efficacy, Bacterial fermentation, Core team, Protective efficacy of.

Let's grow together!

I humbly request your help to keep doing what I do best: provide the world with unbiased sources, definitions and images. Your donation direclty influences the quality and quantity of knowledge, wisdom and spiritual insight the world is exposed to.

Let's make the world a better place together!

Like what you read? Help to become even better: