Dr. Keiji Fukuda, WHO’s director-general for health security and environment, cautioned Monday against injecting the virus with fluorescent dye that has been used to track viruses, dyes or DNA.
“I am concerned about the safety of this technique if not carefully used,” he said.
Human body cells contain DNA and RNA strands. Altering their pattern causes a virus to “infect” and turn a cell a different way.
Viruses do this by attaching themselves to what is called a primer RNA molecule. This may increase the virulence of an infection. By changing the nanoparticles’ nucleic acid structure, they can become “protein catalysts” that enable other parts of the viral genomic contents to bind to the treated surface of the host cell.
But Fukuda cautioned that changing the nucleic acid structure of nanoparticles may prevent the viruses from recognizing the nanoparticles and activating the proteins they harbor.
“It will be very important to develop effective controls over this technique,” he said.
WHO believes that only about 10,000 people worldwide are infected with the varicella zoster virus. Vaccination against the virus is recommended for those who are child and elderly, have compromised immune systems or are immune globally.
WHO said last week that in September, about a third of 10,000 H1N1 influenza vaccinations worldwide were ineffective, and at least 5.1 million doses were unused. Although Germany and Austria vaccinated adults, populations in Thailand, Portugal and Turkey were not vaccinated.
But experts estimate the vaccine strain may have been responsible for varying success, as vaccination campaigns differed substantially from country to country.
“Given the difficulties that are reported with anti-viral vaccines, as well as resistance to A(H1N1) in humans, WHO is therefore advising national health authorities to thoroughly assess the efficacy of any seasonal influenza vaccine before promoting it for the influenza season 2019,” said Fukuda.
WHO has selected a new antigen for the seasonal vaccine to be introduced in early 2019.