Global Warming Would End The Black Death

Some very particular things have to happen for an epidemic of plague to break out:

An infectious rodent population must be present, in which an ‘epizootic’ outbreak has been caused by blocked Y. pestis carrying fleas.

The temperature must be between 15-20°C, with 90-95% humidity, since cold and heat retard the flea’s activity, whilst humidity of under 70% kills it. This limits the outbreaks to particular seasons in Europe.

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