Covid-19
Editor's note : Because of the intense, ongoing, global research efforts related to Covid-19, it's difficult to get an accurate picture of the unknown factors. Here are some of the many as-yet-unanswered questions
| Why does the virus have much more serious effects in older people? | current research | partially understood |
| Were less virulent variants in circulation prior to the major Wuhan outbreak? | current research | unknown |
| Has the virus reached peak virulence / infectivity? | current research | unknown |
| Will anti-viral drugs eventually be able to cure the disease? | current research | partial results |
| What is the incidence of 'Long Covid'? | current research | insufficient data ref. |
| Is the incidence of 'Long Covid' affected by the number of times a patient has had Covid? | current research | unknown |
| What range of symptoms does 'Long Covid' present? | current research | under review |
| How long-lasting are the symptoms of ‘Long Covid’? | current research | unknown |
| Is the often-reported 'Brain Fog' part of ‘Long Covid’? | current research | unknown |
| Is 'Brain Fog' caused by the virus directly infecting the brain? | current research | unknown |
| How long does vaccine protection last? | current research | estimated only |
| How long do infection-generated antibodies remain effective? | current research | estimated only |
| Which other mammals can contract covid? | current research | Growing list |
| Which animals can transmit to humans? | current research | not known |
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