There’s another thunderstorm rolling into town with lighting on the horizon which is starting to flash through my bedroom window. It seems apropos at the start of a weekend which is likely to be defined as the one in which the state of Alabama finally woke up to the realities of the Delta variant. Those of us who have been paying attention for the last month have been watching the numbers and the trends with some alarm all month but the general population has been blithely conducting its usual business in a serene optimism that pandemic dangers are past. Over the last few days, the news has become too major to ignore and in both public and private spheres, folk have woken up to the fact that we’re in for a wild ride.
What’s happened? The rolling seven day average of Covid cases in Alabama, which were at about 200 a day at the first of the month is now ten times that with a positivity rate pushing 20%. (Per WHO pandemic guidelines – positivity rates (the percentage of positive tests for pandemic illness) should be under 5% to be able to lower mitigation measures and those over 10% should be treated as panic stations). The number of hospitalized in Alabama is also up ten fold over the course of the month with more rolling in every hour. The rate of new diagnoses is shooting up in a steeper curve than even during the worse of this past winter’s surge. Delta is playing around. It’s R0 (the number of people a carrier is able to infect) is much higher than original strains of Covid. Where that was between 2 and 3, Delta is somewhere between 5 and 10. That doesn’t seem like much difference until you realize we’re dealing with exponential math. A disease with an R0 of 2.5 will spread to about 100 people after six iterations. A disease with an R0 of 7.5 will spread to nearly 25,000 people in the same six iterations.
There are hysterical headlines appearing regularly ‘Vaccines not as effective as thought’. ‘Vaccinated can spread the virus as easily as the unvaccinated’. When you look closely at this material, much of which is from non-journalistic and science sources, you find that much of what is written is misrepresenting the actual data on which the sensationalism is based so I’m going to try and take a minute to parse out what we really know about the Delta variant at this time. Mind you, much of what we know is somewhat sketchy as it’s not been around that long. Some of this comes from studies done in India, where the mutation that caused the variant originally arose. Some of this comes from studies done in the UK which had the Delta variant earlier than most Western countries due to its cultural/travel links with India. Some of this comes from study of a cluster outbreak of Delta variant stemming from the traditional gathering of gay men in Provincetown, Massachusetts over the 4th of July weekend which led to a significant spreading among a crowd of healthy and fully vaccinated folk who likely spent a good deal of their time on the dance floor.
-The Delta variant is not a new disease. It is a mutation of the coronavirus which causes covid-19 into a form that is more easily transmissible. There is some evidence that it may also be more virulent and cause worse disease.
-The vaccines administered so far have been effective. They are not 100% proof against a breakthrough infection (somewhere around 10% of vaccinated people can develop disease if exposed). However, vaccinated people have had much milder diseases. In the Provincetown cluster mentioned above, more than 1,000 cases were identified. Fewer than 20 required hospitalization (usually short term) and no one to date has died.
-It is not known if a third booster vaccine would improve immunity against the Delta variant. There are no recommendations for this at this time and the federal system which pays for vaccines will not authorize administration of a third vaccine at this time. The original cohort of people who volunteered to be guinea pigs for the vaccine a year ago are being studied and we may know more about this from their data in a few months.
– It appears that some (but not all) people with breakthrough infections can transmit the virus to others. For this reason, the CDC is again recommending indoor masking for the vaccinated. This is a new finding which is why the CDC is changing its advice from a few months ago. Science constantly updates itself with new empirical evidence. When the CDC changes guidelines, it’s not because its being inconsistent, it’s because it’s learning new things about the virus and is trying to help us adapt.
-Unvaccinated people are highly vulnerable to the Delta variant. It takes roughly 6-8 weeks from initiation of vaccination to achieve full vaccination status with Pfizer or Moderna so the time to get vaccinated is now, not next week. The hospitalization rates are skyrocketing due to the large percentages of unvaccinated and therefore vulnerable people and the infectiousness of Delta.
-The best weapons we have against Delta are the ones we have always had. Wash your hands. Keep your distance when you can. Mask up (again) when indoors with those you don’t know. It’s a piece of cloth, not barbed wire or chainmail. Masks work, but only when we all wear masks.
-No, I don’t think we need to go into lockdown. The vaccines are effective, the majority of those most vulnerable to the virus have been vaccinated. We just need to exercise common sense. Those who have regular contact with vulnerable adults such as those working in health care need to be vaccinated if they have not been already. It’s not about you, it’s about the people you care for. Vaccine mandates are coming and will really increase once the FDA moves vaccines from emergency use to approved status.
-Studies of vaccination of children under 12 are ongoing. We may have results in a few months but not before the start of the school year. Universal masking in schools is a good idea, no matter what your political leanings. While there are lots of news stories about children’s hospitals filling up, children, as a whole do not remain at major risk for serious disease. If you have children too young for vaccination, the best thing to do to protect them is to ensure that all family members and close contacts 12 and over are vaccinated.
It still remains to be seen what’s going to happen to the mortality statistics. The health system has gotten much better at treating the disease than it was a year and a half ago and the people succumbing currently, in the unvaccinated population, tend to be younger and physiologically healthier. The mortality rate may not skyrocket the way the case rate is currently doing but we’re going to have to wait a few weeks to find out. I don’t wish ill on anyone but I also don’t understand those who have refused to take a few simple steps to protect themselves from a deadly disease.
My favorite story about exponential math is one I remember from an elementary school textbook, one I likely had in fifth or sixth grade. In it, they described a legend connected with the invention of chess. Apparently, the Sultan of some unnamed kingdom was so impressed with the game that he invited the inventor to his palace and asked him what he would like as a reward. The inventor replied that he asked for very little, just some grains of rice. One grain of wheat for the first square, two grains of wheat for the second square, four grains of wheat for the third square, eight grains of wheat for the fourth square and so on, doubling with each square. The Sultan took the inventor for a fool, cried ‘Done’ and asked for a bag of wheat to be brought. The Sultan, of course made the mistake of thinking that exponential math works like linear math when it does not. There are 64 squares on a chess board. Two to the 64th power is somewhere in the quintillions and would generate enough wheat to bury the entire state of California to a depth of five feet in wheat.
There aren’t that many people in the state of Alabama so, if the disease is that contagious, it will spread very, very rapidly through the susceptible population and likely burn itself out relatively quickly. This is more or less what happened in India. I just hope it manages to do so without crushing the health system and with a minimum of mortality and severe morbidity but we shall see what we shall see. In the meantime, you all know the drill. Get those masks back out and put them on indoors in public. Keep your distance. Wash your hands. Convince your loved ones to go get a vaccine NOW.