Century-Old Vaccine Investigated as a Weapon Against Coronavirus
彭博社 Bloomberg
https://tinyurl.com/wcz3guf
A vaccine that’s been used to prevent tuberculosis is being given to
health-care workers in Melbourne to see if it will protect them against the
coronavirus.
The bacillus Calmette-Guerin, or BCG, shot has been used widely for about 100
years, with a growing appreciation for its off-target benefits. Not only is
it a common immunotherapy for early-stage bladder cancer, it also seems to
train the body’s first line of immune defense to better fight infections.
With an immunization specifically targeted against the pandemic-causing
Covid-19 disease at least a year away, the World Health Organization says it’
s important to know whether the BCG vaccine can reduce disease in those
infected with the coronavirus, and is encouraging international groups to
collaborate with a study led by Nigel Curtis, head of infectious diseases
research, at the Murdoch Children’s Research Institute in Melbourne.
“It can boost the immune system so that it defends better against a whole
range of different infections, a whole range of different viruses and
bacteria in a lot more generalized way,” said Curtis, who’s also a
professor of pediatric infectious diseases at the University of Melbourne and
head of the infectious diseases unit at the city’s Royal Children’s
Hospital.
Hospital staff who volunteered to be part of a six-month trial in Australia
involving 4,000 health-care workers will be randomly allocated to be
vaccinated starting Monday against seasonal influenza and TB, or the flu shot
only.
A placebo vaccine won’t work as a control in this case because the BCG shot
typically causes a localized skin reaction that leaves a scar, making it
obvious which group received the TB vaccination.
Similar research is going on in the Netherlands. Curtis, in an interview
Saturday, said he’s in discussions with potential trial sites in other
Australian cities as well as Boston.
Although the inexpensive vaccine, which is used to immunize some 130 million
newborns worldwide each year, may potentially offer protection to a broader
group of people, the priority is on health workers who are at higher risk
from being infected with coronavirus while caring for sick patients.
“We need to think of every possible way that we can protect health-care
workers,” Curtis said. “And there’s going to be a particular need to
reduce the amount of time that our health-care workers are absent.”
Studies in infants in Africa have shown that the BCG vaccine offers
protection against TB and other pediatric infections, probably by enhancing
the body’s innate immune system