Two conundrums puzzle COVID‐19 investigators: 1) morbidity and mortality is rare among infants and young children and 2) rates of morbidity and mortality exhibit large variances across nations, locales, and even within cities. It is found that the higher the rate of pneumococcal vaccination in a nation (or city) the lower the COVID‐19 morbidity and mortality. Vaccination rates with Bacillus Calmette–Guerin, poliovirus, and other vaccines do not correlate with COVID‐19 risks, nor do COVID‐19 case or death rates correlate with number of people in the population with diabetes, obesity, or adults over 65.
Infant protection may be due to maternal antibodies and antiviral proteins in milk such as lactoferrin that are known to protect against coronavirus infections. Subsequent protection might then be conferred (and correlate with) rates of Haemophilus influenzae type B (Hib) (universal in infants) and pneumococcal vaccination, the latter varying widely by geography among infants, at‐risk adults, and the elderly.
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