My grandmother’s baby brother died of diphtheria . Another of her brothers died during World War I, of what was then called the Spanish flu . I am old enough to remember patients in iron lungs due to paralysis caused by polio infections. Do we really need to go back in time to those days? Do we want to go back to when we worried about birth defects from Rubella and serious complications from measles , mumps and chickenpox ?

Once herd immunity decreases, we put everyone at risk, (“ Western states put ‘safety before politics,’ issue unified vaccine guidance, ” Sept. 17).

Marjorie Muilenburg, Portland

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