Tag: vaccine

SA Scientists Warn Local COVID Variant May Resist Vaccine

South African scientists have said that there is a “reasonable concern” that the South African strain of SARS-CoV-2 may have greater resistance to current vaccines, and underscored the need for global vaccination.

Speaking to the BBC,  Prof Shabir Madhi, who has led vaccine trials in South Africa, explained, “It’s a theoretical concern. A reasonable concern… that the South African variant might be more resistant.” 

The South African variant has mutated far more than the UK variant, raising the possibility that it may be able to evade the antibodies that typically fight coronavirus.

Prof Helen Rees, a vaccine expert at Wits University, said, “Fortunately, should further modifications of the vaccine be required to address the new variants, some of the vaccine technologies under development could allow this to be done relatively rapidly.”

South African scientists recently pushed back against the notions that the SA variant was more transmissible than the UK one, or that it is more deadly. Explaining the reason for the flight restrictions from South Africa, UK Health Secretary Matt Hancock has stated that he believed it was more infectious than the UK variant, saying “This is a very, very significant problem […] and it’s even more of a problem than the UK new variant.”
The UK variant has a “transmission advantage” of 0.4 to 0.7, leading to reproduction numbers of 1.4 to 1.8.Prof Madhi said laboratory tests would determine whether current vaccines would be effective against this variant in a few weeks.

Source: BBC News 

COVID Vaccines May Lose Potency as Virus Evolves

Looking to a time beyond the development of COVID vaccines, researchers are attempting to determine how long the SARS-CoV-2 virus will take to develop resistance to those vaccines.

David Kennedy, assistant professor of biology at Pennsylvania State University said, “A COVID-19 vaccine is urgently needed to save lives and help society return to its pre-pandemic normal,” said David Kennedy, assistant professor of biology. “As we have seen with other diseases, such as pneumonia, the evolution of resistance can quickly render vaccines ineffective. By learning from these previous challenges and by implementing this knowledge during vaccine design, we may be able to maximise the long-term impact of COVID-19 vaccines.”

The researchers recommend that vaccines be designed to create multiple immune responses, making it harder for the vaccine to survive the immune system’s attack, much the way multiple antibiotics are used to suppress bacterial infections, by forcing the virus to have multiple mutations to survive.

Strongly suppressing virus transmission through the host is key to minimising the amount of mutation and thereby the lifespan of the vaccine’s  effectiveness.

“According to the World Health Organization, at least 198 COVID-19 vaccines are in the development pipeline, with 44 currently undergoing clinical evaluation,” said Kennedy. “We suggest that the risk of resistance be used to prioritise investment among otherwise similarly promising vaccine candidates.”

Source: SciTech Daily