MIT scientists, including one of Indian origin, have developed a new easily customisable vaccine that can be rapidly deployed in response to disease outbreaks such as Ebola and H1N1 influenza.
The vaccine, that can be manufactured in one week, consists of strands of genetic material known as messenger RNA, which can be designed to code for any viral, bacterial, or parasitic protein, researchers said.
These are then packaged into a molecule that delivers the RNA into cells, where it is translated into proteins that provoke an immune response from the host, they said.
In addition to targeting infectious diseases, researchers are using this approach to create cancer vaccines that would teach the immune system to recognise and destroy tumours.
"This nanoformulation approach allows us to make vaccines against new diseases in only seven days, allowing the potential to deal with sudden outbreaks or make rapid modifications and improvements," said Daniel Anderson from Massachusetts Institute of Technology (MIT) in the US.
RNA vaccines are appealing because they induce host cells to produce many copies of the proteins they encode, which provokes a stronger immune reaction than if the proteins were given on their own, researchers said.
The idea of using messenger RNA molecules as vaccines has been around for about 30 years, but one of the major obstacles has been finding a safe and effective way to deliver them, they said.
Researchers including Jasdave Chahal and Omar Khan from MIT customised RNA sequences, which enabled them to produce nearly any protein they want.
The RNA molecules also include instructions for amplification of the RNA, so that the cell will produce even more of the protein.
The vaccine is designed to be delivered by intramuscular injection, making it easy to administer. Once the particles get into cells, the RNA is translated into proteins that are released and stimulate the immune system, researchers said.
The vaccines were able to stimulate both arms of the immune system - a T cell response and an antibody response.
In tests in mice, those that received a single dose of one of the vaccines showed no symptoms following exposure to the real pathogen - Ebola, H1N1 influenza, or Toxoplasma gondii, researchers said.
"No matter what antigen we picked, we were able to drive the full antibody and T cell responses," said Khan.
Researchers also believe that their vaccines would be safer than DNA vaccines, another alternative that scientists are pursuing, because unlike DNA, RNA cannot be integrated into the host genome and cause mutations.
"Typically a vaccine becomes available long after the outbreak is over. We think we can become interventional over the course of a real outbreak," said Chahal.
The findings were published in the journal Proceedings of the National Academy of Sciences.
The MR vaccine campaign targets around 41 crore children
across the country, the largest ever in any such campaign. All children aged between 9 months and less than 15 years will be given a single shot of Measles-Rubella (MR) vaccination irrespective of their previous measles/rubella vaccination status or measles/rubella disease status, the official said.
The vaccine will be provided free-of-cost across the states from session sites at schools, health facilities and outreach session sites. Measles vaccine is currently provided under Universal Immunisation Programme (UIP). However, rubella vaccine will be a new addition, he said.
Measles is a disease which is an important cause of death in children. It is highly contagious and spreads through coughing and sneezing of an infected person, the release said.
It makes a child vulnerable to life threatening complications such as pneumonia, diarrhoea and brain infection. Globally in 2015, measles killed an estimated 1,34,200 children mostly under five years of age. In India, it killed an estimated 49,200 children, the Health Ministry official said.
Rubella is generally a mild infection, but has serious consequences if infection occurs in pregnant women, causing congenital rubella syndrome (CRS), which is a cause of public health concern, he said.
CRS is characterized by congenital anomalies in the foetus and newborns affecting the eyes, ears, brain and heart defects, causing a huge socio-economic burden on the families in particular and society in general.
In 2010, an estimated 1,03,000 children were born with CRS (congenital rubella syndrome) globally, of which around 47,000 children, i.E. 46 per cent were in South-East Asia Region, the official said.
Through this campaign, it is aimed to rapidly build up immunity in the susceptible cohort, thereby decreasing rubella burden in the country, according to the release.
The measles disease burden was brought down by introduction of second dose of measles vaccine in 2010.
However, those gain need to be supplemented, and in order to further reduce the burden, country is going to carry out the Measles-Rubella campaign.
Measles immunisation directly contributes to the reduction of under-five child mortality, and with combination of rubella vaccine, will control rubella and prevent CRS in country population, he said.
Union Ministers Sadananda Gowda and Ananth Kumar, Karnataka Medical Education minister Sharanaprakash Rudrappa Patil, state Health Minister K R Ramesh Kumar and actor Ramesh Arvind were present on the occasion.
Communication material to raise awareness about the initiative was also launched.
