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What is mRNA Vaccine for HIV AIDS? Why is developing the HIV vaccine tough?

What is mRNA Vaccine for HIV AIDS? Why is developing the HIV vaccine tough?


  • GS 3 || Science & Technology || Health & Medicine

Why in the news?

mRNA Vaccine for HIV AIDS

What is mRNA?

  • A single-stranded RNA (RiboNucleic Acid) molecule called messenger RNA (mRNA) is complementary to one of a gene’s DNA strands.
  • The mRNA is an RNA form of the gene that leaves the nucleus and travels to the cytoplasm, where it is translated into proteins.
  • A ribosome runs along the mRNA during protein synthesis, scans its base sequence, and uses the genetic code to translate each three-base triplet, or codon, into its matching amino acid.

What is the mRNA vaccine?

  • Proteins to produce: These vaccines rely on messenger RNA molecules, which instruct the body’s cells on which proteins to produce.
  • Covid-19: The spike protein of the coronavirus SARS-CoV-2, which causes Covid-19, is coded by the mRNA to tell the cells to recreate it.
  • The spike protein — which appears as spikes on the surface of the coronavirus — is what starts the infection process; it allows the virus to penetrate cells, after which it replicates.
  • Make copies: Once administered into the body, a coronavirus vaccine based on mRNA instructs the body’s cells to make copies of the spike protein.
  • As a result, immune cells are expected to produce antibodies to combat it.
  • If and when the true virus penetrates the human body, these antibodies will remain in the blood and combat it.


  • The quest to develop an HIV vaccine is considered important for scientific research.
  • Improved the longevity: While treatment with Antiretroviral Therapy has significantly improved the longevity of those with AIDS.
  • According to the World Health Organization, there are around 37.7 million living with HIV as of 2020.
  • Traditional vaccine approaches have not worked for HIV, and in fact, some of them have gone on to worsen the infection.
  • RNA-based immunogens are believed to be a promising alternative because they do not involve the use of a live virus, can be made relatively easily, can be quickly deployed and safely administered.

mRNA Vaccine vs. Traditional Vaccines:

  • Vaccines train the body to recognise and respond to proteins produced by disease-causing organisms like viruses and bacteria.
  • Inactivated doses: Traditional vaccinations are made up of tiny or inactivated doses of the entire disease-causing organism, or the proteins it produces, that are injected into the body to elicit an immune response.
  • They function by exploiting mRNA, or messenger RNA, which is the molecule that essentially puts DNA instructions into action, to deceive the body into manufacturing some of the viral proteins itself. Inside a cell, mRNA serves as a template for the production of proteins.
  • Immune system: Small or inactivated doses of disease-causing organisms or proteins produced by them make up traditional vaccinations. These inactivated organisms are injected into the body in order to stimulate the immune system so that it responds against the disease-causing germs.


  • Non-infectious: As RNA vaccines are not constructed from an active pathogen (or even an inactivated pathogen), they are non-infectious.
  • In contrast, traditional vaccines require the production of pathogens, which, if done at high volumes, could increase the risks of localized outbreaks of the virus at the production facility.
  • RNA vaccines can be produced faster, cheaper, and in a more standardized fashion (i.e. fewer error rates in production), which improves responsiveness to outbreaks.
  • An additional ORF coding for a replication mechanism can be added to amplify antigen translation and therefore immune response, decreasing the amount of starting material needed.

Risks of the mRNA Vaccine:

  • Inflammation: Some mRNA-based vaccine platforms elicit significant interferon type I responses, which have been linked to inflammation as well as the possibility of autoimmune.
  • Fragile mRNA molecule: Because the fragile mRNA molecule should be quickly broken down inside the body once its drug delivery system has eroded, the risks associated with mRNA strands that failed to pass into a human cell are considered to be low.
  • Risk of unknown short- and long-term effects: Because mRNA vaccines are new, and no mRNA technology platform had ever been approved for human use before 2020, there is the risk of unknown short- and long-term effects.
  • To be stored at extremely low temperatures: Even though mRNA is extremely fragile, vaccines must be stored at extremely low temperatures to avoid degrading and providing little real immunity to recipients; the BioNtech/Pfizer COVID-19 vaccine, for example, must be stored at -70 degrees Celsius, which may disadvantage developing countries with tropical climates.


  • Drastically cutting the rates of transmission: Of the people living with HIV, over two-thirds are in Africa. Any success in containing the HIV pandemic would mean drastically cutting the rates of transmission there.
  • However, as the experience with the Moderna and Pfizer vaccines shows, getting essential jabs to the regions where they are most needed is the biggest stumbling block.
  • Sensitive to temperature: Another challenge with mRNA vaccines is that they are sensitive to temperature in storage, and is a challenge for developing countries.
  • Mammalian cell heredity: The vaccine’s mRNA strand may trigger an unexpected immunological response. To mitigate this, the mRNA vaccination sequence may have an effect on mammalian cell heredity.
  • Although RNA in the body quickly degrades, getting the vaccine into cells is incredibly difficult.
  • RNA vaccines must be stored at a very low temperature. As a result, it will only be stored in locations with a cold storage chain.


The volatility of mRNA vaccines used to be a disadvantage. The experience with the coronavirus vaccination, on the other hand, has been a breath of fresh air. The effectiveness of mRNA vaccines, such as those developed by Pfizer-BioNTech and Moderna, in lowering hospitalisation and mortality has given rise to trust in the technology.

Additional info:

  • Human immunodeficiency virus (HIV)
    • It’s an infection that targets the body’s immune system, primarily CD4 cells, which are white blood cells.
    • HIV damages CD4 cells, lowering a person’s resistance to diseases like tuberculosis and several malignancies.
    • If a person’s CD4 cell count drops below 200, their immunity is significantly weakened, making them more vulnerable to diseases. AIDS (acquired immunodeficiency syndrome) is diagnosed when the CD4 count falls below 200.
    • HIV can be detected using both rapid diagnostic tests and self-tests, which are both simple and inexpensive.
    • HIV testing services must adhere to the 5Cs: consent, confidentiality, counselling, accurate results, and linkage to treatment and other resources.
    • This early detection increases treatment options and lowers the danger of transmission to others, such as sexual or drug-sharing partners.
  • Symptoms:
    • Many persons who are infected with HIV do not experience symptoms for the first few months after infection and may be unaware that they are infected.
    • Others may have flu-like symptoms such as fever, headache, rash, and sore throat. However, the virus is most infectious during the first few months.
    • Symptoms will become more widespread and strong as the disease advances.
    • Swollen lymph nodes, weight loss, fever, diarrhoea, and cough are some of the symptoms.

Mains oriented question:

What are the advantages of mRNA? How discovery of mRNA vaccine can be effective in fighting with Covid-19 virus and its spread in future? (200 words)