Until a coronavirus vaccine is ready, pneumonia vaccines can reduce deaths from COVID-19


The annual flu season threatens to make the COVID-19 pandemic doubly deadly, but I think it’s not inevitable.There are two commonly administered vaccines – the pneumococcal vaccine and the Hib vaccine – that protect against bacterial pneumonia. These bacteria complicate both the flu and COVID-19, often resulting in death. My review of disease trends and vaccination rates leads me to believe that wider use of pneumococcal and Hib vaccines could guard against the worst effects of a COVID-19 disease.

I am an immunologist and physiologist interested in the effects of combination infections on immunity. I reached my point by juxtaposing two seemingly unrelated puzzles: infants and children get SARS-CoV-2, the virus that causes COVID-19, but are very rarely hospitalized or die; and the number of cases and death rates from COVID-19 began to vary widely from nation to nation and city to city even before the lockdowns began. I wondered why.

One evening I woke up with a possible answer: vaccination rates. Most children from the age of two months are vaccinated against many diseases; adults less. And infant and adult immunization rates vary widely across the world. Could differences in vaccination rates against one or more diseases explain the differences in the risks of COVID-19? As someone who had previously investigated other pandemics such as the great influenza pandemic of 1918-1919 and AIDS, and who worked with vaccines, I had a solid background in researching the relevant data to test my hypothesis.

Pneumococcal vaccination rates correlate with lower COVID-19 cases and deaths

I collected national and local data on vaccination rates for influenza, polio, measles-mumps-rubella (MMR), diphtheria-tetanus-pertussis (DTP), tuberculosis (BCG), pneumococci and Haemophilus influenzae type B (Hib). I correlated them with the COVID-19 case rates and death rates of 24 countries that had experienced their COVID-19 outbreaks around the same time. I controlled for factors such as the percentage of the obese, diabetic or elderly population.

I have found that only pneumococcal vaccines provide statistically significant protection against COVID-19. Countries like Spain, Italy, Belgium, Brazil, Peru and Chile that have the highest COVID-19 rates per million have the lowest pneumococcal vaccination rates in infants and adults . The countries with the lowest rates of COVID-19 – Japan, Korea, Denmark, Australia, and New Zealand – have the highest rates of pneumococcal vaccination in infants and adults.

A recent pre-printed (not yet peer-reviewed) study conducted by researchers at the Mayo Clinic also reported very strong associations between pneumococcal vaccination and protection against COVID-19. This is especially true in patients belonging to minorities who are most affected by the coronavirus pandemic. The report also suggests that other vaccines, or combinations of vaccines, such as Hib and MMR may also provide protection.

These results are important because in the United States, vaccination of children against pneumococci – which protects against Streptococcus pneumoniae bacteria – varies by condition from 74% to 92%. Although the CDC recommends that all adults aged 18 to 64 in high risk groups for COVID-19 and all adults over 65 receive a pneumococcal vaccination, only 23% of high-risk adults and 64% of those over 65 do so.

Likewise, although the CDC recommends that all infants and some adults at high risk be vaccinated against Haemophilus influenzae type B (Hib), only 80.7% of children in the United States and a handful of immunologically compromised adults have been compromised. Pneumococcal and Hib vaccination rates are significantly lower in minority populations in the United States and in countries that have been hit harder by COVID-19 than the United States.

Based on this data, I advocate universal pneumococcal and anti-Hib vaccination in children, at-risk adults, and all adults over 65 to prevent serious COVID-19 illness.

Left: Combined rates of pneumococcal vaccination in children and adults (over 65) (out of 200 possible). Right: COVID-19 population cases (per million) approximately 90 days before the pandemic for 24 countries. Countries with high pneumococcal vaccination rates have low rates of COVID-19 cases.

How pneumococcal vaccination protects against COVID-19

Protection against serious COVID-19 disease by pneumococcal and Hib vaccines makes sense for several reasons. First, recent studies reveal that the majority of COVID-19 hospital patients, and in some studies almost all, are infected with streptococci, which cause pneumococcal pneumonia, Hib, or other pneumonia-causing bacteria. Pneumococcal and Hib vaccinations are expected to protect coronavirus patients from these infections and thus significantly reduce the risk of severe pneumonia.

I have also found that vaccines against pneumococcus, Hib, and possibly rubella can confer specific protection against the SARS-CoV-2 virus that causes COVID-19 by means of “molecular mimicry”.

Molecular mimicry occurs when the immune system thinks that one microbe looks like another. In this case, the proteins present in the pneumococcal vaccines and, to a lesser extent, those present in the Hib and rubella vaccines also resemble several proteins produced by the SARS-CoV-2 virus.

Two of these proteins found in pneumococcal vaccines mimic the tip and membrane proteins that allow the virus to infect cells. This suggests that pneumococcal vaccination may prevent infection with SARS-CoV-2. Two other mimics are the nucleoprotein and the replicase which control the replication of the virus. These proteins are made after viral infection, in which case pneumococcal vaccination can control, but not prevent, the replication of SARS-CoV-2.

Either way, these vaccines can provide indirect protection against SARS-CoV-2 infection that we can implement now, even before we have a specific viral vaccine. Such protection may not be complete. People can still suffer from a weakened version of COVID-19 but, like most infants and children, be protected from the worst effects of the infection.

Fighting influenza-related pneumonia during the COVID-19 pandemic

While the specific protection these other vaccines provide against COVID-19 has yet to be tested in a clinical trial, I advocate a broader implementation of pneumococcal and Hib vaccination for an additional, well-validated reason. .

Pneumococcal and Hib pneumonia – both caused by bacteria – are the leading causes of death from viral influenza. The influenza virus rarely causes death directly. Most often, the virus makes the lungs more susceptible to bacterial pneumonia, which is fatal. Dozens of studies around the world have shown that increasing pneumococcal and Hib vaccination rates dramatically reduces influenza-related pneumonia.

Similar studies show that the cost of using these vaccines is offset by savings due to lower rates of influenza-related hospitalizations, ICU admissions, and death. In the context of COVID-19, reducing the rates of influenza-related hospitalizations and ICU admissions would free up resources to fight the coronavirus, regardless of any effect these vaccines might have on SARS-CoV- 2 himself. In my opinion, this is a winning scenario.

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In short, we don’t need to wait for a SARS-CoV-2 vaccine to slow COVID-19.

I think we can and must act now by fighting the coronavirus with all the tools at our disposal, including the flu, Hib, pneumococcus and maybe rubella vaccination.

Preventing the pneumococcal and Hib complications of influenza and COVID-19, and perhaps the proxy vaccination against SARS-CoV-2 itself, helps everyone. Administering these already available and well tested pneumococcal and Hib vaccines to populations will save money by freeing up hospital beds and intensive care units. It will also improve public health by reducing the spread of multiple infections and boost the economy by promoting a healthier population.


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