the times | Monday November 9 2020 1GT 3
times
The lowdown
Brideshead
GETTY IMAGESInstitute, and she views mouthwash
as being of “great interest”. When I
contact her, she says it may be
comparable to the situation “with
vitamin D, where randomised trials
don’t exist for this virus, but other
suggestive evidence is there.
“We take the view that policy-
makers could consider whether the
in vitro data is strong enough to
make a recommendation around
wider use of this as a potential
preventative intervention for
transmission,” O’Donnell says.
Iodine has a historic pedigree. In the
4th century, before iodine had been
isolated, Theophrastus, a pupil of
Aristotle, recorded that iodine-rich
seaweed could treat sunburn.
The element was discovered
accidentally in 1811, during the
Napoleonic Wars, by a man hoping to
find a cheap way to make gunpowder.
He instead found a way of treating
seaweed to produce beautiful and
curious purple crystals. Within
decades it was used on battle wounds
during the American Civil War, and
during the First World War Alexander
Fleming found iodine better than its
rivals to prevent gangrene.
By the 1960s iodine was made safer
by bonding it with other chemicals;
this is the modern form called
povidone-iodine. A study in the
journal Dermatology in 1997 called this
“the most potent antiseptic available”.
“The big game-changer was earlier
this year when it was realised just how
high the virus loads in the mouth and
nose are,” Challacombe tells me over
the phone. “As an example, just lick
your lips”. He pauses. “You will have
put about 10 to 15 microlitres of saliva
on your lips right now.”
A study has shown that in the first
week of infection a typical Covid-
carrier may have 10,000 viral particles
per microlitre of saliva. It is suggested,
Challacombe says, that you need only
1,000 viral particles to get infected.
“And you have just put 100,000 viral
particles on your lips, many, many
times the dose,” he says. If I then
touch my mouth — I can’t help doing
it as he mentions it — speak loudly,
cough or sneeze, my saliva will be
spreading about me, he says. “I think
people have underestimated the power
of transmission.”
We think of Covid-19 as a coughing
illness and assume that the well of
infection is in the lungs. However,
a study in the Journal of Dental
Research in April found that actually
it is more active in the salivary
glands. This was a key shift in
understanding: the mouth wasn’t just
being contaminated by the lungs, it
was likely to be the main swampy
breeding ground of the disease. “The
virus replicates in the salivary glands
in the mouth, of which you have
hundreds,” Challacombe says.
Test-tube studies comparing
different common mouthwashes, such
as chlorhexidine, show that the iodine
mouthwash performs better. The other
benefit is that it is gentle enough to
use as a spray up the nose. “If you
put those things together, you can
see if you’ve got people with these
extremely high values of Covid in the
mouth, that if you give them an iodine
mouthwash you will reduce that risk
immediately,” Challacombe says. “And
I think it’s an entirely reasonable
question to ask: what is the downside
of everybody using it?”
Challacombe says that the priority
are healthcare workers, especially
those working with a lot of saliva,
such as anaesthetists and dentists.
The American Dental Association,
and equivalent bodies in Australia
and South Africa, have recommended
that dentists ask their patients to
mouthwash with iodine or
chlorhexidine before procedures. The
British Dental Association has refused
to follow suit; Professor Damien
Walmsley, its scientific adviser, says it
is waiting to see results of larger trials.
“This advice that I have just told you
did go out to Nervtag [the New and
Emerging Respiratory Virus ThreatsAdvisory Group], which is the
scientific committee below Sage,”
Challacombe says. “The question they
asked is: how long did it last? And of
course we didn’t have that evidence.
That’s what has held it back.”
In response, he has begun a study,
endorsed by the National Institute
for Health Research, to investigate
that point, but the low numbers of
Covid hospital admissions over the
summer stalled progress.
“It’s perhaps one of the most
frustrating things I’ve been involved
in,” Challacombe tells me. “Having set
up a clinical trial to prove this, with
anaesthetists at the Royal Surrey
Hospital, we ran out of patients and
had to pause. Now this is not good
news for patients in the short term,
but it may be better from a clinical-
trial point of view that it looks like the
patients are coming in again now.
“So that’s the big unknown.
Meanwhile, we put out a very
conservative estimate that it would
last at least 20 minutes. And we
thought this would be long enough
for anaesthetists to get a tube down
and a dentist to do a treatment.”
In September another joint German
and American study, published in the
Journal of Medical Virology, tested
mouthwashes against test tube
coronavirus. It led the study’s author,
Craig Meyers, professor of
microbiology at Penn State College
of Medicine, to conclude: “I would
say wear your mask, do your social
distancing. Do what you’re supposed
to be doing, but this could just be an
extra help.”
What is the responsible course of
action? In August the governor of
Osaka in Japan looked at the limited
but encouraging human studies of
iodine mouthwash on Covid-19 and
told the public: “It’s worth giving a try.”
Japan already has an established
culture of using iodine mouthwash
against common infections, but
within hours there was panic-buying
across the country, leaving the
shelves bare. The Osaka governor’s
comments got a slap from the World
Health Organisation Centre for
Health Development, which
responded: “There’s no scientific
evidence that gargling medicine
prevents the coronavirus.”
This Osaka story echoes worries
about President Trump championing
unproven treatments for Covid-19,
such as hydroxychloroquine, which in
larger trials was found to be ineffective
against the virus.
Could it be the same for iodine
mouthwash? Quite possibly. If you
want to give it a go, this mouthwash
is not sold commercially in the UK.
Instead look for solutions of 10 per
cent povidone-iodine specifically
designed to be taken orally. In both
cases, Challacombe says the test-tube
evidence shows that the most effective
dilution against Covid-19 is 1:200 or
0.5 per cent. So if you get your hands
on an iodine mouthwash, which is
made of 1 per cent povidone-iodine,
you dilute it 50:50 with water. Or if
you use a 10 per cent solution of oral
iodine, you dilute it 1:20 with water.
Gargle for 30 seconds or so, and not
more than two or three times a day.
For the purposes of this article I
did both — I ordered a European
mouthwash off the internet and also
made a DIY version. When I got a
scratchy throat one night, I gargled
with it. It tastes like swimming pool
water. The next morning, I felt
better, but not exactly wiser.The virus
replicates
in the
salivary
glands in
the mouth,
of which
you have
hundreds
Watch out — the Sloanes are
coming back.Did they ever go away? I know
plenty.Sure, but they haven’t been cool
for at least a decade (for which
they can thank the spoilt brats
on Made in Chelsea). Luckily for
them, I foresee better days; for their
relevance to be, ahem, revisited.Is that a pun?
Good spot, old chap! Can you
guess what for?No. Don’t call me old chap.
Why the devil not? I’m talking
about a new adaptation of
Brideshead Revisited, after all.
A star-studded remake of Evelyn
Waugh’s epic high society novel
of 1945 is coming to the BBC and
HBO and starts filming next year.Ugh — another one? I watched the
2008 version and it was quite
underwhelming.This will be better. It is to be
directed by Luca Guadagnino of
Call Me By Your Name fame and
will reportedly star Andrew
Garfield, Taylor Swift’s boyfriend
Joe Alwyn, Cate Blanchett, Ralph
Fiennes and Rooney Mara.And some peaches, presumably? I
can’t unsee that film’s Timothée
Chalamet scene. *shudders*No peaches — just posh people.
You might recall that the original
television adaption in 1981 caused
quite the stir. It ran for weeks when
there were only a few TV channels
and fuelled an obsession with
wealthy young socialites. The lead
role, Charles Ryder, was played
by Jeremy Irons — quite the dish
then. Ditto Anthony Andrews,
who played his teddy-bear-carting
contemporary Sebastian Flyte.Not nearly as dishy as Garfield or
Alwyn, though. Those two with
plummy accents I can get excited
about. You’re right, though, this is
good news for the Sloane Rangers.
To which end, can I make a polite
request about all this?Go on.
Please, let’s not tell them.
Hannah Rogers