Have You Herd of Immunity?

 

We are learning a lot about this novel coronavirus. Russia seems hell-bent on releasing a vaccine without any large-scale clinical trials. Putin wants bragging rights and is willing to risk Russian lives in an experiment to find out if what he has is the holy grail of vaccines. Or is it only partially or temporarily effective? Are there any side effects? The people of Russia are the guinea pigs. We’re months away from a viable vaccine… if we are lucky. Even the World Health Organization is warning against bringing a vaccine to market too soon.

At least we are learning to treat serious COVID-19 infections better, dropping the mortality rate of those requiring ventilators to survive. But all this as virus-deniers and antivaxxers are attempting to convince us that the disease should just fade away on its own. Herd immunity, they say, is imminent. Except they are on the wrong side of scientific evidence. “Herd immunity can be achieved when so many members of a population have become immune to an infectious disease that it can’t find new people to infect. There are two ways to get there: by exposing a large percentage of the population to a virus so they can develop antibodies on their own, or by vaccinating enough people to interrupt its transmission.

“The story of the coronavirus outbreak at San Quentin State Prison offers a cautionary tale for those who say the first option would be the best way to bounce back from the pandemic… The virus spread unchecked across California’s oldest prison in ways that stunned public health experts. Despite concerted efforts to control its transmission, it has infected more than 2,200 people and caused 25 deaths among a population of roughly 3,260 people. If it were equally dangerous across the state as a whole, that would translate to a death toll of 300,000 — nearly 30 times what we’ve seen so far. And if the virus were to cause an equivalent amount of damage nationwide, a staggering 2.5 million Americans would lose their lives.

“Sweden, whose light-touch coronavirus strategy drew international attention and speculation about the possibilities of herd immunity, now has one of the highest COVID-19 mortality rates in Europe — one that’s worse than that of the United States. Plus, it appears to be nowhere near reaching herd immunity, with only 7% of the population testing positive for coronavirus antibodies. ‘In light of these findings, any proposed approach to achieve herd immunity through natural infection is not only highly unethical, but also unachievable,’ wrote two virologists in the journal the Lancet.” Diya Chacko for the August 11th Los Angeles Times Coronavirus Daily Update. There are lots of other myths that those who do not want to be “inconvenienced” by the novel coronavirus believe, especially about the purported “invulnerability of children,” the ineffectiveness of medically advised preventative measures and the magical six-foot rule.

“Eager for schools to reopen and to return to the old ‘normal,’ President Trump has been proclaiming his opinion that children are ‘virtually immune’ or ‘almost immune’ to infection with the coronavirus… That’s false. A new report from the American Academy of Pediatrics and the Children’s Hospital Association found that at least 97,000 children in the U.S. tested positive for the coronavirus in the last two weeks of July, with at least 338,000 U.S. children testing positive since the pandemic began. Consistent with their policy on misleading claims about COVID-19, Facebook and Twitter removed Trump’s posts on the subject.” YahooNews.com, August 12th. Americans are Trump’s guinea pigs to try and show he is going to open the economy no matter who has to suffer or die. Including children.

We’re noticing the above serious uptick in infections and long-term effects from children getting the virus. Although their anatomical systems are, on the whole, more resistant to serious consequences, children can have lasting impairment or even face death from the virus and its aftereffects. MIS-C (multisystem inflammatory syndrome in children) can cause permanent brain and nerve damage. Bouts with Kawasaki disease following a COVID-19 infection can seriously damage organs in young bodies and even result in death. Without contact tracing and constant testing, the risks of in-school primary and secondary education are substantial: “As the nation focuses on safety issues around going back to school during the pandemic, a new report found a sharp increase in the number of Covid-19 cases among children in the United States.

“There has been a 90% increase in the number of Covid-19 cases among children in the United States over the last four weeks, according to a new analysis by the American Academy of Pediatrics and the Children's Hospital Association that will be updated weekly… Dr. Sean O'Leary, vice-chair of the American Academy of Pediatrics Committee on Infectious Diseases, told CNN's Anderson Cooper on Monday that coronavirus cases in children should be taken seriously.” CNN.com, August 11th. And even asymptomatic children can become carriers of the disease, infecting teachers, siblings, fellow students and family members.

Schools need expensive retrofitting to accommodate in-person study, which should only occur when the infection rate justifies (5% of those tested or less). Even the restrooms, where ventilation isn’t perfect and there are no floor-to-ceiling doors on the stalls, are dangerous. One flush sends droplets into the air, where they can hover for minutes unless there is solid air flow. And that six-foot rule? Forgetaboutit!

“All over the country Americans are being told to stay safe by maintaining a six foot distance from one another in public settings. Unsettlingly, a new study finds that those suggestions may be very insufficient. There is still a lot we don’t understand about the airborne transmission of the coronavirus, but researchers have found that just a slight 2.5 MPH breeze can propel saliva 18 feet in five seconds!

“‘The droplet cloud will affect both adults and children of different heights,’ comments study co-author Dimitris Drikakis in a release by the American Institute of Physics. ‘Shorter adults and children could be at higher risk if they are located within the trajectory of the traveling saliva droplets.’

“Whenever anyone coughs, saliva is inevitably released and travels through the air in a suspended state. Of course, the distance saliva travels depends on a number of factors; the size and amount of droplets, how the droplets are interacting with one another, rate of evaporation, the transference of heat and mass, and air conditions (humidity, temperature).

“To study saliva movements through the air, the research team created a computational fluid dynamics simulation. That simulation is capable of analyzing the characteristics of every single saliva droplet traveling through the air via a cough. The simulation also accounts for additional factors like dispersion force, humidity, saliva/air molecule interactions, and the transition of droplets from liquid to vapor.”

“The simulation is displayed on a computer as a grid that represents the entirety of space in front of a coughing person. The analysis for this study encompassed 1,008 saliva droplets and roughly 3.7 million subsequent equations.

“‘Each cell holds information about variables like pressure, fluid velocity, temperature, droplet mass, droplet position, etc.,’ co-author Talib Dbouk says. ‘The purpose of the mathematical modeling and simulation is to take into account all the real coupling or interaction mechanisms that may take place between the main bulk fluid flow and the saliva droplets, and between the saliva droplets themselves.’

“To study saliva movements through the air, the research team created a computational fluid dynamics simulation. That simulation is capable of analyzing the characteristics of every single saliva droplet traveling through the air via a cough. The simulation also accounts for additional factors like dispersion force, humidity, saliva / air molecule interactions, and the transition of droplets from liquid to vapor.

“The simulation is displayed on a computer as a grid that represents the entirety of space in front of a coughing person. The analysis for this study encompassed 1,008 saliva droplets and roughly 3.7 million subsequent equations… ‘Each cell holds information about variables like pressure, fluid velocity, temperature, droplet mass, droplet position, etc.,’ co-author Talib Dbouk says. ‘The purpose of the mathematical modeling and simulation is to take into account all the real coupling or interaction mechanisms that may take place between the main bulk fluid flow and the saliva droplets, and between the saliva droplets themselves.’” Study.org, May 20th. As their chart above suggests, indoor spaces, unless there is sufficient air movement, are particularly vulnerable. For some interesting additional graphics and a deeper understanding of what it really takes to achieve herd immunity, see my June 13th Are We Just Going to Learn to Live with Massive Death Tolls? blog.

For those who have followed the political wishes of conservative politicians promising a quick end to the virus and a wide and continued reopening of the economy, the horrific existing results speak for themselves. It does seem as if those who have followed the advice of qualified scientists and doctors have fared incredibly better. For the record, the virus has not only not faded, it has simply gotten so much worse.

            I’m Peter Dekom, and when you read how New Zealand – imposing travel restrictions, requiring lockdowns for a while, social distancing, wearing of masks, applied contact tracing and constant testing – has now experienced well over consecutive 100 days with only four new COVID-19 infections, you know how absolutely our government has failed in containing this pandemic.