Despite promising news coming from Pfizer last week of a potential Covid-19 vaccine, another chilling development has also been confirmed.

Three Iowans have now been diagnosed with reinfection of the coronavirus.

KCRG is reporting that MercyOne Des Moines has recently treated one "extremely sick" patient and two others who displayed milder symptoms, described as becoming "moderately ill" thus confirming a diagnosis of a contracting second round of coronavirus infection.

All three Iowans have had Covid-19 once before, providing mounting evidence that reinfection is not only possible but is already happening in Iowa.

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According to KCCI, MercyOne's Dr. Ravi Vemuri said people diagnosed with Covid-19 can continue to test positive for up to 90 days after their initial infection, as they continue to shed cells.

The CDC website says there are concerns that contracting the virus once does not provide immunity, but also says more studies are needed.

So with winter approaching, along with the arrival of cold and flu season, the possibility that you can catch Covid-19 more than once is a reason to seriously step up your protection plans.

Hand washing, social distancing, and mask-wearing are simply essential if Iowans want to avoid becoming a statistical addition to the growing number of cases, now topping over 50 million people worldwide. The other major thing to avoid this winter is any large indoor gatherings.

Source: KCRG, KCCI, CDC

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