The Hope Held out Amid Despair by new messenger RNA vaccine

Context: The future of immunity may lie in the use of molecular couriers that deliver genetic instructions for human cells to arm up.

Evolution of Vaccines:

• Origin (18^th Century): from the Latin word vacca, meaning cow, when Edward Jenner used the cowpox virus as a “live" source to inoculate humans against the deadly smallpox.
• Types of Vaccines:

• Live Attenuated Vaccines (LAVs): in which live disease infected pustules were used against diseases like tuberculosis(TB), rotavirus, yellow fever, measles and mumps and have risks associated.
• Inactivated vaccines (IV): It use parts of bacteria or virus that were not alive and are used today against types of influenza and rabies. (The Oxford-AstraZeneca vaccine is an inactive type vaccine.)
• Sub-unit or Acellular vaccines (AV): These focus on proteins that coat the pathogen that easily triggers our immune system response. These are classified as:

• Toxoid (AV-T): where the response is to the toxic substance that the protein uses to attack body with; these include the vaccines against tetanus and diphtheria.
• Purified antigen (AV-PA): where the body reacts to a concentrated version of the protein and are used to fight pneumococcal infections; only require pieces of germs and booster doses.
  • m-RNA vaccines: or messenger RNA refers to the molecular couriers that deliver genetic instructions; Its advantages are:
    • Cuts the time taken for vaccine development: by teaching human cells to make a protein similar to one found on the virus.
    • Are Safe: since they do not integrate into the genome and disintegrate a few days after they enter the cell.
    • May help in designing vaccines: against lentivirus (HIV), the plasmodium parasite that causes malaria, and the bacteria that causes TB.

Challenges to vaccine development:

• Vaccines generally take years of research and despite that, we do not still have effective vaccines against disease viruses like hepatitis C, HIV, Zika and West Nile.
• Requirement of cold storage: mRNA vaccines typically require very low temperatures to maintain efficacy and safety.

Conclusion: mRNA science is the future of man- kind’s fight against pathogens, especially those that take an alarmingly high toll.

P.S. “Science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world," said microbiologist Louis Pasteur.