Silver Bullet May 14 - New CDC guidelines, Spike protein and vascular damage
A weekly update on all things COVID-19. News, public health guidance, trends, breakthroughs, and thousands of scientific papers distilled down to what you need to know right now.
Changing guidance from the CDC
Contrary to widespread scientific opinion, the CDC has long held that SARS-CoV-2 spreads via droplets, not aerosols. Meanwhile, evidence for aerosol transmission, such as the famous church choir superspreader event, has piled up. Aerosol scientists have pointed out fundamental errors in the agency’s definition of aerosols and droplets. Now the CDC has finally updated its guidance to reflect airborne, or aerosol, transmission of the virus. In a new brief, the CDC states, “The smallest very fine droplets, and aerosol particles formed when these fine droplets rapidly dry, are small enough that they can remain suspended in the air for minutes to hours.” The guidance warns that people more than 6 feet away from an infected person may still be infected. The change has prompted calls for more public health emphasis on indoor ventilation for workplaces.
The CDC also updated its guidance for people fully vaccinated against COVID-19 to say that they no longer need to wear a mask or maintain physical distance in any setting, except where required by law. They also do not need to be tested following an exposure to COVID-19, or for travel.
Science open letter asks that lab leak theory be taken seriously
Eighteen prominent scientists have signed a letter published in the journal Science calling for a more thorough investigation of a possible laboratory origin for SARS-CoV-2. They say that the WHO investigation was not thorough enough to rule out a lab leak as the source of the virus, and that a more transparent investigation should be carried out. Technology Review published a response from Shi Zhengli, chief scientist for emerging disease at the Wuhan Institute of Virology, around which the lab leak theory revolves. Shi objected to the letter, asking, “Who can provide an evidence that does not exist?” Although most people concerned about a laboratory spillover as the origin of SARS-CoV-2 have focused on the WIV, it’s important to note that hundreds or thousands of laboratories around the world have similar capabilities, and that the geographical origin of the virus has not been definitively pinned down to Wuhan. That is merely the location of the first major outbreak.
Report shows children spread the virus
A report from Israel’s Ministry of Health concludes that children were more likely to test positive for COVID-19 than adults between January and September, 2020, that a majority of them were asymptomatic, and that opening the education system on September 2, 2020 led to a significant increase in cases. Subsequently, closing schools resulted in a significant decrease in cases. From the report: “According to the analysis provided above, children are certainly infected and infect others. Because most of them do not present symptoms, it is difficult to identify a significant portion of children carrying the virus, and they may constitute a source for infecting others.” It recommends that education systems reopen gradually and in a manner that reflects the level of cases in the area.
Similarly, a study from the University of Kentucky showed that a return to in-person learning in Texas resulted in at least 43,000 additional COVID-19 cases and 800 deaths within the first two months. The results are published in a working paper by the National Bureau of Economic Research.
Spike protein damages endothelial cells by binding ACE2
Spike protein is widely known to facilitate viral entry into cells of the respiratory system by binding ACE2. A new study in Circulation Research now reveals that it also wreaks havoc on vascular endothelial cells by disrupting signaling from ACE2 to the mitochondria, resulting in damage to the mitochondria. Mitochondria supply energy to the cell. The authors say that even without infecting and reproducing inside cells, the spike protein would do damage to the blood vessels. This mechanism helps to elucidate COVID-19’s devastating effects on the vascular system.
COVID risk rises even in the high end of normal BMI range
Obesity is well established as a risk factor for more severe illness with COVID-19, and those risks are known begin for those with a BMI in the overweight range (over 25 kg/m2). However, a further investigation published in The Lancet Diabetes and Endocrinology shows a linear relationship between the risk of hospital admission and BMI starting at 23 kg/m2, the top of the normal range. There was also a linear relationship between BMI and ICU admission across the entire range of BMI. For the lower range of BMI, the different relationship could be explained by an association with frailty. Frail individuals would be more vulnerable to severe illness, hence, having higher rates of hospitalization, and also would be less likely to be admitted to the ICU. The mechanisms for the strong association between body fat and COVID-19 risks are not clear, and, according to this study are not explained by comorbidities like type 2 diabetes. In fact, in this study, people with type 2 diabetes were at lower risk for severe COVID-19 outcomes per unit increase in BMI than those without.
Other science news
Biden administration investigating energy attacks
More than 130 people have been injured by mysterious events that are believed to be a form of energy attack, possibly microwaves, The New York Times reports. Only 60 cases had been previously confirmed, mostly located in China and Cuba. The new total adds cases from Europe and Asia, as well as two from Washington D.C. in the immediate vicinity of the White House. The most recent attack occurred two weeks ago. The symptoms reported include sensations of pain, pressure, and sound. Some victims have suffered long term brain damage. The National Academy of Sciences has released a report on the illnesses, which have commonly been known as Havana syndrome, because the first known cases occurred in Cuba.
MDMA succeeds in Phase 3 PTSD trial
In a Phase 3 trial for severe PTSD, treatment with MDMA in combination with talk therapy induced a “significant and robust” reduction in symptoms, according to a new study in Nature Medicine. There were no adverse events noted in the study, and the authors conclude that MDMA, also known as ecstasy or molly by those who use it recreationally, was highly efficacious as a treatment for PTSD. Many patients don’t respond to existing therapies, including SSRIs, exposure therapy, and cognitive behavioral therapy. MDMA increases sociability, decreases anxiety, and induces feelings of euphoria. It was first developed by Merck in 1912, and was used in the 1970s as an aid to psychotherapy. However, after MDMA became popular as a recreational drug, it was made a Schedule I drug, hampering further studies of it as a therapy. A second successful Phase 3 trial will need to be completed before the drug can be approved for use by the FDA. That trial is already underway, and approval is possible as early as 2023.
In depth
Op-ed: why I mandated the COVID vax for our staff, by Marc L. Boom, MD, MedPage Today