A few days ago, I asked for and received the PCV-13 pneumonia vaccine, and a few days earlier, the flu shot. These vaccines are free if you are over 65, but you have to ask for them. PCV-13 is the milder of the pneumonia vaccines, providing moderate resistance to 12 common pneumonia strains, plus a strain of diphtheria. There is a stronger shot, with more side-effects. The main reason I got these vaccines was to cut my risk from COVID-19.

Some 230,00 people have died from COVID-19. Almost all none of them were under 20, and hardly any died from the virus itself. As with the common flu, they died from side infections and pneumonia. Though the vaccine I took is not 100% effective against event these 13 pneumonias, it is fairly effective, especially in the absence of co-morbidities, and has few side effects beyond stiffness in my arm. I felt it was a worthwhile protection, and further reading suggests it was more worthwhile than I’d thought at first.

It is far from clear there will be a working vaccine for SARS-CoV-2, the virus that causes COV-19. We’ve been trying for 40 years to make a vaccine against AIDS, without success. We have also failed to create a working vaccine for SARS, MERS, or the common cold. Why should SARS-CoV-2 be different? We do have a flu vaccine, and I took it, but it isn’t very effective, viruses mutate. Despite claims that we would have a vaccine for COVID-19 by early next year, I came to imagine it would not be a particularly good vaccine, and it might have side effects. On the other hand, there is a fair amount of evidence that the pneumonia vaccine works and does a lot more good than one might expected against COVID-19.

A colleague of mine from Michigan State, Robert Root Bernstein, analyzed the effectiveness of several vaccines in the fight against COVID-19 by comparing the impact of COVID-19 on two dozen countries as a function of all the major inoculations. He found a strong correlation only with pneumonia vaccine: “Nations such as Spain, Italy, Belgium, Brazil, Peru and Chile that have the highest COVID-19 rates per million have the poorest pneumococcal vaccination rates among both infants and adults. Nations with the lowest rates of COVID-19 – Japan, Korea, Denmark, Australia and New Zealand – have the highest rates of pneumococcal vaccination among both infants and adults.” Root-Bernstein also looked at the effectiveness of adult inoculation and child inoculation. Both were effective, at about the same rate. This suggests that the the plots below are not statistical flukes. Here is a link to the scientific article, and here is a link to the more popular version.

I decided to check up on Root-Bernstein’s finding by checking the state-by state differences in pneumonia vaccination rates — information available here — and found that the two US states that were hardest hit by COVID, NY and NJ, have among the lowest rates of inoculation. Of course there are other reasons at play. These states are uncommonly densely populated, and the governments of both made the unfortunate choice of sending infected patients to live in old age homes. At least half of the deaths were in these homes.

Pneumonia vaccination may also explain why the virus barely affected those under 20. Pneumonia vaccines was available only in 2000 or so. Many states then began to vaccinate about then and required it to attend school. The time of immunization could explain why those younger than 20 in the US do so well compared to older individuals, and compared to some other countries where inoculation was later. I note that China has near universal inoculation for pneumonia, and was very mildly hit.

I also took the flu shot, and had taken the MMR (measles) vaccine last year. The side effects, though bad, are less bad than the benefits, I thought, but there was another reason, and that’s mimicry. It is not uncommon that exposure to one virus or vaccine will excite the immune system to similar viruses, so-called B cells and T-cell immunity. A recent study from the Mayo Clinic, read it here, shows that other inoculations help you fight COVID-19. By simple logic, I had expected that the flu vaccine would help me this way. The following study (from Root-Bernstein again) shows little COVID benefit from flu vaccine, but evidence that MMR helps (R-squared of 0.118). Let men suggest it’s worth a shot, as it were. Similar to this, I saw just today, published September 24, 2020 in the journal, Vaccines, that the disease most molecularly similar to SARS-CoV-2 is pneumonia. If so, mimicry provides yet another reason for pneumonia vaccination, and yet another explanation for the high correlations shown above.

As a final comparison, I note that Sweden has a very high pneumonia inoculation rate, but seems to have a low mask use rate. Despite this, Sweden has done somewhat better than the US against COVID-19. Chile has a low inoculation rates, and though they strongly enforced masks and social distance, it was harder hit than we were. The correlation isn’t 100%, and masks clearly do some good, but it seems inoculation may be more effective than masks.

Robert Buxbaum, November 7, 2020.