From the Guidelines
The incubation period of measles averages 10-12 days from exposure to prodrome and 14 days from exposure to rash, with a range of 7-18 days. This information is based on the study by the Advisory Committee on Immunization Practices (ACIP) 1. The incubation period is a critical factor in understanding the spread of the disease, as individuals with measles are contagious from 4 days before the rash appears until 4 days after. Key points about the incubation period and contagiousness include:
- The average incubation period is 10-12 days from exposure to the onset of initial symptoms, such as fever, and 14 days from exposure to the appearance of the rash.
- The range of the incubation period can vary from 7 to 18 days, as noted in the ACIP study 1.
- Infected individuals are not contagious during the entire incubation period but become contagious approximately 4 days before the rash appears.
- The contagious period extends until about 4 days after the rash emerges, highlighting the importance of isolation to prevent the spread of the disease.
- The measles virus is highly contagious, with a secondary attack rate of over 90% among susceptible individuals, underscoring the importance of vaccination for prevention, as discussed in the context of measles prevention strategies 1.
From the Research
Incubation Length for Measles
- The incubation length for measles is not explicitly stated in the provided studies 2, 3, 4, 5, 6.
- However, the studies discuss various aspects of measles, including post-exposure prophylaxis, vaccination, and immune globulin administration.
- Study 5 mentions that contacts were identified between 13 March 2013 and 30 June 2013, and PEP effectiveness was calculated for MMR, IG, and any PEP for nonimmune contacts aged <19 years, but it does not provide information on the incubation length.
- Study 6 provides summary recommendations of the Advisory Committee on Immunization Practices (ACIP) for the prevention of measles, rubella, congenital rubella syndrome, and mumps, but it does not mention the incubation length for measles.
- Since the provided studies do not directly address the incubation length for measles, there is no specific information available to answer this question based on the given evidence.