Measles (Rubeola)
What is Measles?
Measles is an acute viral respiratory illness.
● Measles, also known as rubeola, is one of the most contagious infectious diseases,
with at least a 90% secondary infection rate in susceptible domestic contacts.
● Despite being considered primarily a childhood illness, measles can affect people of
all ages.
● Measles is marked by prodromal fever, cough, coryza, conjunctivitis, and
pathognomonic enanthem (ie, Koplik spots), followed by an erythematous
maculopapular rash on the third to seventh day.
● Infection confers lifelong immunity.
Pathophysiology
In temperate areas, the peak incidence of infection occurs during late winter and spring.
https://www.youtube.com/watch?v=YBceTQ97FnM
● Infection is transmitted via respiratory droplets, which can remain active and
contagious, either airborne or on surfaces, for up to 2 hours.
● Initial infection and viral replication occur locally in tracheal and bronchial epithelial
cells.
● After 2-4 days, measles virus infects local lymphatic tissues, perhaps carried by
pulmonary macrophages.
● Following the amplification of measles virus in regional lymph nodes, a
predominantly cell-associated viremia disseminates the virus to various organs prior
to the appearance of a rash.
● Measles virus infection causes a generalized immunosuppression marked by
decreases in delayed-type hypersensitivity, interleukin (IL)-12 production and
antigen-specific lymphoproliferative responses that persist for weeks to months after
the acute infection.
Statistics and Incidences
The practice of administering 2 doses of live-attenuated measles vaccine to children to prevent
school outbreaks of measles was implemented when the vaccine was first licensed in 1963.
, ● The immunization program resulted in a decrease of more than 99% in reported
incidence.
● From 1989 to 1991, a major resurgence occurred, affecting primarily unvaccinated
preschoolers; this measles resurgence resulted in 55,000 cases and 130 deaths and
prompted the recommendation that the second dose of measles vaccine be given to
preschoolers in a mass vaccination campaign that led to the effective elimination in
the United States of endemic transmission of the measles virus.
● By 1997-1999, the incidence of measles had been reduced to a historic low (< 0.5
cases per million persons).
● From 1997 to 2004, the reported incidence was as low as 37-116 cases per year.
● From 2000 through 2007, an average of 63 cases were reported annually to the US
Centers for Disease Control and Prevention (CDC).
● In 2004, 34 cases were reported; after that all-time low, however, the annual
incidence began to increase, with most cases linked either directly or indirectly to
international travel.
● In 2005, 66 cases of measles were reported to the CDC. Of these, 34 were linked to
a single outbreak in Indiana associated with the return of an unvaccinated
17-year-old American traveling in Romania.
● In 2006, a total of 49 confirmed cases were reported in the United States.
● From January to June 2008, 131 cases of measles were reported to the CDC.
● At least 47% of the 131 measles infections were in school-aged children whose
parents chose not to have them vaccinated.
● In the period from January 1 to May 20, 2011, a total of 118 cases were reported to
the CDC; this represents the highest reported number of measles cases for the same
period since 1996.
● Of the 118 cases, 105 (89%) were associated with importation; the source of the
remaining 13 cases could not be ascertained.
● In all, 105 (89%) of the 118 patients were unvaccinated; 24 (20%) were persons 12
months to 19 years of age whose parents claimed a religious or personal exemption.
● Approximately half of the 118 cases—58, or 49%—were accounted for by 9
outbreaks.
● The largest of these outbreaks involved 21 persons in Minnesota, in a setting where
parental concerns about the safety of measles, mumps, and rubella (MMR) vaccine
caused many children to go unvaccinated.
● As a result of this outbreak, many persons were exposed, and at least 7 infants too
young to receive MMR vaccine were infected.
● From January 1 to May 23, 2014, 288 confirmed cases were reported to the CDC, a
figure that exceeds the highest reported annual total number of cases (220 cases in
2011) since measles was declared eliminated in the United States in 2000.
● In developing countries, measles affects 30 million children a year and causes 1
million deaths.
● Measles causes 15,000-60,000 cases of blindness per year.
What is Measles?
Measles is an acute viral respiratory illness.
● Measles, also known as rubeola, is one of the most contagious infectious diseases,
with at least a 90% secondary infection rate in susceptible domestic contacts.
● Despite being considered primarily a childhood illness, measles can affect people of
all ages.
● Measles is marked by prodromal fever, cough, coryza, conjunctivitis, and
pathognomonic enanthem (ie, Koplik spots), followed by an erythematous
maculopapular rash on the third to seventh day.
● Infection confers lifelong immunity.
Pathophysiology
In temperate areas, the peak incidence of infection occurs during late winter and spring.
https://www.youtube.com/watch?v=YBceTQ97FnM
● Infection is transmitted via respiratory droplets, which can remain active and
contagious, either airborne or on surfaces, for up to 2 hours.
● Initial infection and viral replication occur locally in tracheal and bronchial epithelial
cells.
● After 2-4 days, measles virus infects local lymphatic tissues, perhaps carried by
pulmonary macrophages.
● Following the amplification of measles virus in regional lymph nodes, a
predominantly cell-associated viremia disseminates the virus to various organs prior
to the appearance of a rash.
● Measles virus infection causes a generalized immunosuppression marked by
decreases in delayed-type hypersensitivity, interleukin (IL)-12 production and
antigen-specific lymphoproliferative responses that persist for weeks to months after
the acute infection.
Statistics and Incidences
The practice of administering 2 doses of live-attenuated measles vaccine to children to prevent
school outbreaks of measles was implemented when the vaccine was first licensed in 1963.
, ● The immunization program resulted in a decrease of more than 99% in reported
incidence.
● From 1989 to 1991, a major resurgence occurred, affecting primarily unvaccinated
preschoolers; this measles resurgence resulted in 55,000 cases and 130 deaths and
prompted the recommendation that the second dose of measles vaccine be given to
preschoolers in a mass vaccination campaign that led to the effective elimination in
the United States of endemic transmission of the measles virus.
● By 1997-1999, the incidence of measles had been reduced to a historic low (< 0.5
cases per million persons).
● From 1997 to 2004, the reported incidence was as low as 37-116 cases per year.
● From 2000 through 2007, an average of 63 cases were reported annually to the US
Centers for Disease Control and Prevention (CDC).
● In 2004, 34 cases were reported; after that all-time low, however, the annual
incidence began to increase, with most cases linked either directly or indirectly to
international travel.
● In 2005, 66 cases of measles were reported to the CDC. Of these, 34 were linked to
a single outbreak in Indiana associated with the return of an unvaccinated
17-year-old American traveling in Romania.
● In 2006, a total of 49 confirmed cases were reported in the United States.
● From January to June 2008, 131 cases of measles were reported to the CDC.
● At least 47% of the 131 measles infections were in school-aged children whose
parents chose not to have them vaccinated.
● In the period from January 1 to May 20, 2011, a total of 118 cases were reported to
the CDC; this represents the highest reported number of measles cases for the same
period since 1996.
● Of the 118 cases, 105 (89%) were associated with importation; the source of the
remaining 13 cases could not be ascertained.
● In all, 105 (89%) of the 118 patients were unvaccinated; 24 (20%) were persons 12
months to 19 years of age whose parents claimed a religious or personal exemption.
● Approximately half of the 118 cases—58, or 49%—were accounted for by 9
outbreaks.
● The largest of these outbreaks involved 21 persons in Minnesota, in a setting where
parental concerns about the safety of measles, mumps, and rubella (MMR) vaccine
caused many children to go unvaccinated.
● As a result of this outbreak, many persons were exposed, and at least 7 infants too
young to receive MMR vaccine were infected.
● From January 1 to May 23, 2014, 288 confirmed cases were reported to the CDC, a
figure that exceeds the highest reported annual total number of cases (220 cases in
2011) since measles was declared eliminated in the United States in 2000.
● In developing countries, measles affects 30 million children a year and causes 1
million deaths.
● Measles causes 15,000-60,000 cases of blindness per year.
