Friday Update for 2021-04-09: Hygiene
Three items of pandemic news you may have missed recently: A tapeworm remedy to fight Covid; you can stop sanitizing now; and a new concern about blood clots with the Johnson & Johnson vaccine. Plus news briefs and a frippery.
Blood clots now a concern with J&J
We have written about the concern with rare blood clots after shots of the AstraZeneca / Oxford vaccine. On Wednesday the European Medicines Agency, the EU’s equivalent of the FDA, released a report concluding that there is a link between the vaccine and those rare cases of clots.
Now multiple outlets are reporting that the EMA is watching four cases of blood clots in people following vaccination with the Johnson & Johnson / Janssen shot. One case occurred in a clinical trial and three were seen during the US vaccine rollout; one case was fatal.
The EMA is concerned because the J&J vaccine has been authorized in Europe. Its rollout is planned to begin later this month. The US is the only place where this vaccine has been widely used so far. Somewhere between 4.5 million and 5 million shots have been delivered here.
None of the news stories so far features a comment from the FDA, so we don’t know if that agency is on alert in the matter of clots.
If the clots are related to vaccine administration — and this has not been proven — it would amount to a rate of about one in a million, which is in the same ballpark as the European AstraZeneca cases.
Both J&J and AZ vaccines use adenovirus vectors. J&J’s is Ad26, a virus that can infect people and cause mild cold symptoms; AZ’s is an adenovirus that infects chimpanzees but not people. In both cases the adenovirus vectors are deactivated so that they cannot reproduce in the human body. The Ad viruses act as a carrier to smuggle SARS-CoV-2 viral proteins into cells in order to alert the immune system.
As far as I can tell, the only other vaccine or candidate that uses an Ad26 vector is the Russian Sputnik V. That vaccine requires two shots and uses a different adenovirus for each: Ad26 for the prime and Ad5 for the boost. Neither EU nor US regulators have approved Sputnik V. Several other vaccines under development are vectored with Ad5, including those from CanSino (Chinese) and AltImmune (American).
Bloomberg quotes an in-house expert as saying, “Adenovirus technologies such as that used by AstraZeneca and others have been associated with clotting in other settings.” Here is one paper I found that reinforces this assertion. This story is developing and we will be following it closely.
You can stop sanitizing now
The CDC has finally updated its guidelines and recommendations regarding the spread of SARS-CoV-2 via surfaces. The agency now says that the odds of contracting Covid-19 from touching a surface are 1 in 10,000. The CDC’s head added, “Disinfection is only recommended in indoor settings — schools and homes — where there has been a suspected or confirmed case of Covid-19 within the last 24 hours.” (The new guidelines don’t apply to health-care settings, where more intensive disinfection may in fact be required.)
The CDC’s update comes many months after most experts had concluded that “fomite” spread plays a minuscule role in transmission.
The old guidelines made a kind of sense when it was thought that the virus spread mainly through large droplets, not through tiny airborne particles. Large droplets, such as from a cough or sneeze, fall to the ground or surfaces within a short distance — that’s where the 6-foot rule comes from.
The NY Times piece on the CDC’s move quotes Rutgers microbiologist Emanule Goldman, who has been arguing since last summer to de-emphasize surface transmission:
The Times notes that commercial establishments — restaurants, grocery stores, dentists’ offices — have long appreciated the excellent optics of compulsive sanitizing. It represents a very visible action that signals an organization’s concern for its visitors and customers. This ritual obsessive sanitizing has always put me in mind of the “politician’s syllogism“: Something must be done. This is something. Therefore we must do it!
The obsessive cleaning and sanitizing that almost everyone has been doing (me included!) since the start of the pandemic can now be viewed as the “hygiene theater” it has always been.
A tapeworm antagonist to fight Covid
Vincent Raciniello, host of This Week in Virology, has a new blog post laying out the promise of Niclosamide in counteracting a SARS-CoV-2 infection. This drug is approved for treating infection by tapeworms.
Niclosamide was identified in a screen of 3,000 small molecules as a promising candidate for interfering with one of the ways the SARS-CoV-2 virus destroys lung cells. This is by syncytia, in which an infected cell fuses with a neighboring uninfected one, resulting in cells with multiple nuclei. Additionally, Niclosamide acts to block virus reproduction.
Niclosamide disrupts syncytia by inhibiting a family of chloride channels called TMEM16. This action, besides getting in the way of the spike protein causing cells to merge, could also reduce the inflammation, thrombosis, and diarrhea that can result from infection with SARS-CoV-2.
This research involved vero (monkey kidney) cells in vitro; human trials have not begun.
- Three US vaccination sites close after J&J reactions — A site in North Carolina noted “several” adverse reactions yesterday immediately following J&J shots, and a site in Colorado clocked 11 reactions ranging from dizziness to nausea. Georgia also closed one site after eight people had adverse reactions among 325 vaccinated with the J&J shot there.
- France encourages a different second shot — With use of the AstraZeneca vaccine restricted in various ways in Europe, the French are the first to suggest that people who have had one shot of AZ should get their booster shot of a different vaccine — one of the mRNA products, from Moderna or Pfizer, that have been authorized in that country.
- Out-of-hospital cardiac arrests spiked with Covid — Incidence of what are called OHCAs were an average of 59% higher, in 50 large cities across 8 countries, in April of 2020 compared to levels in 2019 and 2018. The OHCAs were not an end result of Covid-19, rather they were an early complication, even of mild cases. The rise in OHCAs tracked each city’s level of Covid-19 cases and preceded the disease peak (so might be used in the future as a leading indicator). Here is a summary from CIDRAP of a paper published in The Lancet.
- A second-generation vaccine — Jason McLellan is the man principally responsible for the pre-fusion stabilized spike protein used in all three of the vaccines authorized in the US to date. McLellan has now come up with an improved version of the “2P” spike, called Hexa-Pro. A vaccine using Hexa-Pro is in human trials in Mexico, Thailand, Brazil, and Vietnam — and the vaccine supplies for those trials were made in those countries. Hexa-Pro vaccines hold out the promise of being extremely cheap and easy to manufacture. And McLellan is now hard at work on a further improved, third-generation spike.
Your frippery today is an introduction to the surreal photography of Elena Sheidlina (anglizized as Ellen Sheidlin), a Russian artist and model. She has gathered 5 million followers on Instagram and it is easy to see why. She says her photos take a week or more to prepare and 10 minutes to shoot.
Friday Update for 2021-04-09: Hygiene — No Comments
HTML tags allowed in your comment: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>