and described by the formula: where A is the amplitude of oscillation, f is the frequency, t is the elapsed time, and is the phase of the oscillation. The phase determines or is determined by the initial displacement at time t = 0. A motion with frequency f has period. Two potential ambiguities can be noted:
Incubation Period Shingles is not transmitted from exposure to another infected person so there is no applicable incubation period. Anyone who has recovered from varicella may develop shingles. Mode of Transmission Transmission of the virus occurs through direct contact with the rash or fluid from the lesions.
1 The average length is 14 to 16 days from exposure, with a range of 10 to 21 days. 2  This may be prolonged in immunocompromised patients and those who have received varicella zoster immune globulin (VZIG).3  The incubation period may be up to 28 days after VZIG. The period of communicability (for normal persons) extends from 1 to 2 days before onset of the rash through the first 5 to 6 days after rash onset. 2  Varicella zoster immune globulin (VZIG) is indicated for a healthy full-term infant who is exposed to chickenpox at home at age 2 weeks.