Starting with the power law for the  number of infections during the middle stages of epidemics, we propose differential equations describing the process of momentum epidemic management, which is a set of measures of any nature aimed at reducing the epidemic spread via timely response to the dynamic of the number of infections. One of the finding is that the aggressive imposing the most significant measures followed by equally aggressive reducing them when the spread diminishes will effectively reduce the number of new infections to zero; we use the theory of Bessel functions. Epidemics may resume after such saturation. Practically: the hesitation before enabling some protection measures must be at least doubled before disabling them. Also, the square root of the intensity of hard measures is qualitatively inversely proportional to the epidemic duration. At least for Covid-19 , Bessel functions appeared surprisingly efficient for modeling the whole period of intensive spread  ; we discuss the USA, and other places .
Starting with the power law for the total number of infections during the middle stages of epidemics, we propose differential equations describing the process of momentum epidemic management, which is a set of measures aimed at reducing the epidemic spread via timely response to the dynamic of the number of infections. In the most aggressive mode, the saturation of the number of infections can be achieved sufficiently quickly, though it can be not the end of the epidemic. The square root of the intensity of hard measures is qualitatively inversely proportional to the epidemic duration. We use the theory of Bessel functions. For Covid-19 , they appeared surprisingly efficient for modeling the whole period of intensive spread , presumably including the late stages ; we discuss the USA, UK, Austria, Israel and Sweden .
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total
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of any nature
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One of the finding is that the aggressive imposing the most significant measures followed by equally aggressive reducing them when the spread diminishes will effectively reduce
In the most aggressive mode, the saturation of
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new infections to zero; we use the theory of Bessel functions. Epidemics may resume after such saturation. Practically: the hesitation before enabling some protection measures must be at least doubled before disabling them. Also, the
infections can be achieved sufficiently quickly, though it can be not the end of the epidemic. The
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At least for
We use the theory of Bessel functions. For
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, Bessel functions
, they
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, presumably including the late stages
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and other places
UK, Austria, Israel and Sweden