Measles is more common now than it used to be. There have been about 60
cases in the first four months of the year, including 22 in NYC. 84% of
the cases were im****t-associated and all but one of the cases involved
an unvaccinated person.
This shows how im****tant vaccination is.
Jeff
From the CDC
<http://www.cdc.gov/mmwr/preview/mmwrhtml/mm57e501a1.htm?s_cid=mm57e501a1_e>:
Measles --- United States, January 1--April 25, 2008
Measles, a highly contagious acute viral disease, can result in serious
complications and death. As a result of a successful U.S. vaccination
program, measles elimination (i.e., interruption of endemic measles
transmission) was declared in the United States in 2000 (1). The number
of re****ted measles cases has declined from 763,094 in 1958 to fewer
than 150 cases re****ted per year since 1997 (1). During 2000--2007,* a
total of 29--116 measles cases (mean: 62, median: 56) were re****ted
annually. However, during January 1--April 25, 2008, a total of 64
confirmed measles cases were preliminarily re****ted to CDC, the most
re****ted by this date for any year since 2001. Of the 64 cases, 54 were
associated with im****tation of measles from other countries into the
United States, and 63 of the 64 patients were unvaccinated or had
unknown or undo***ented vaccination status. This re****t describes the 64
cases and provides guidance for preventing measles transmission and
controlling outbreaks through vaccination, infection control, and rapid
public health response. Because these cases resulted from im****tations
and occurred almost exclusively in unvaccinated persons, the findings
underscore the ongoing risk for measles among unvaccinated persons and
the im****tance of maintaining high levels of vaccination.
Measles cases in the United States are re****ted by state health
departments preliminarily to CDC, and confirmed cases are re****ted
officially via the National Notifiable Disease Surveillance System,
using standard case definitions† and case classifications. Cases are
considered im****tation associated if they are 1) acquired outside the
United States (i.e., international im****tation) or 2) acquired inside
the United States and either epidemiologically linked via a chain of
transmission to an im****tation or accompanied by virologic evidence of
im****tation (i.e., a chain of transmission from which a measles virus is
identified that is not endemic in the United States). Other cases in the
United States are classified as having an unknown source.
During January 1--April 25, 2008, a total of 64 preliminary confirmed
measles cases were re****ted from the following areas: New York City (22
cases), Arizona (15), California (12), Michigan and Wisconsin (four
each), Hawaii (three), and Illinois, New York state, Pennsylvania, and
Virginia (one each) (Figure). Patients ranged in age from 5 months to 71
years; 14 patients were aged <12 months, 18 were aged 1--4 years, 11
were aged 5--19 years, 18 were aged 20--49 years, and three were aged
>50 years, including one U.S. resident born before 1957.§
Fourteen (22%) patients were hospitalized; no deaths were re****ted.
Transmission occurred in both health-care and community settings. One of
the 44 patients for whom transmission setting was known was an
unvaccinated health-care worker who was infected in a hospital.
Seventeen (39%) were infected while visiting a health-care facility,
including a child aged 12 months who was exposed in a physician's office
when receiving a routine dose of measles, mumps, and rubella (MMR)
vaccine.
Fifty-four (84%) of the 64 measles cases were im****tation associated: 10
(16%) of the 64 were im****tations (five in visitors to the United States
and five in U.S. residents traveling abroad) from Switzerland (three),
Israel (three), Belgium (two), and India and Italy (one each); 29 (45%)
cases were epidemiologically linked to im****tations; and 15 (23%) cases
had virologic evidence of im****tation. The remaining 10 (16%) cases were
from unknown sources; however, all occurred in communities with
im****tation-associated cases. Specimens from 14 patients were genotyped
at CDC, and four different genotypes were identified: three from Arizona
(genotype D5), three from California (D5), five from New York City (one
in a case epidemiologically linked to an im****ted case from Belgium and
four in cases in communities where im****tations from Israel had
occurred; all D4), two from Wisconsin (H1), and one from Michigan (D5).
Fifty-six of the 64 measles cases re****ted in 2008 have occurred in five
outbreaks (defined as three or more cases linked in time or place). In
New York City, an outbreak of 22 cases has been re****ted, including four
im****tations and 18 other cases (10 im****tation associated). In Arizona,
15 cases have been re****ted; the index patient was an unvaccinated adult
visitor from Switzerland. In San Diego, California, 11 cases have been
re****ted, and an additional case spread to Hawaii; the index patient in
the San Diego outbreak was an unvaccinated child who had traveled to
Switzerland. In Michigan, four cases have been re****ted; the index
patient was an unvaccinated youth aged 13 years with an unknown source
of infection. In Wisconsin, four cases have been re****ted; the index
patient was a person aged 37 years with unknown vaccination status who
likely was exposed to a Chinese visitor with measles-compatible illness.
Sixty-three of the 64 patients were unvaccinated or had unknown or
undo***ented¶ vaccination status, and one patient had do***entation of
receiving 2 doses of MMR vaccine. None of the five patients who were
visitors to the United States had been vaccinated. Among the 59 patients
who were U.S. residents, 13 were aged <12 months and too young to be
vaccinated routinely, seven were children aged 12--15 months and had not
yet received vaccination, 21 were children aged 16 months--19 years,
including 14 (67%) who claimed exemptions because of religious or
personal beliefs (Table). Among the 18 patients aged >20 years, 14 had
unknown or undo***ented vaccination status, two had claimed exemptions
and acquired measles in Europe, one had evidence of immunity because of
birth before 1957, and one had do***entation of receiving 2 doses of MMR
vaccine.
Of the five U.S. residents with measles who were vaccine eligible and
had traveled abroad, all were unvaccinated. One was a child aged 15
months who was not vaccinated before travel, and two were adults who
were unvaccinated because of personal belief exemptions. For two adults,
the reason for not being vaccinated was unknown.
Re****ted by: SB Redd, PK Kutty, MD, AA Parker, MSN, MPH, CW LeBaron, MD,
AE Barskey, MPH, JF Seward, MBBS, JS Rota, PA Rota, PhD, L Lowe, PhD, WJ
Bellini, PhD, Div of Viral Diseases, National Center for Immunization
and Respiratory Diseases, CDC.
Editorial Note:
Although ongoing measles transmission was declared eliminated in the
United States in 2000 (1) and in the World Health Organization (WHO)
Region of the Americas in 2002 (2), approximately 20 million cases of
measles occur each year worldwide. The 2008 upsurge in measles cases
serves as a reminder that measles is still im****ted into the United
States and can result in outbreaks unless population immunity remains
high through vaccination. Among the 64 confirmed measles cases, prior
vaccination could be do***ented for only one person.
Before introduction of measles vaccination in 1963, approximately 3 to 4
million persons had measles annually in the United States; approximately
400--500 died, 48,000 were hospitalized, and 1,000 developed chronic
disability from measles encephalitis (1). Even after elimination of
endemic transmission in 2000, im****ted measles has continued to create a
substantial U.S. public health burden; of the 501 measles cases re****ted
during 2000--2007, one in four patients was hospitalized, and one in 250
died (1).
Thus far in 2008, five U.S. residents and five visitors have been
do***ented as acquiring measles abroad. Of these 10 persons, nine
acquired measles in the WHO European Region. These im****tations likely
are related to an increase in 2008 in measles activity in Europe. In
Switzerland, approximately 2,250 measles cases have been re****ted since
November 2006. The Swiss measles outbreak started in Lucerne, where the
measles vaccination coverage level in children is 78%, and spread across
the country, predominantly affecting children aged 5--15 years who were
unvaccinated because of parental opposition to vaccination.** In Israel
(which is included in the WHO European Region), a measles outbreak with
approximately 1,000 cases is ongoing (Ministry of Health, Israel,
unpublished data, 2008), and measles transmission is occurring in other
European countries, predominantly among populations opposed to
vaccination. This situation prompted travel advisories to be issued in
the United States and Europe.†† Health-care providers should advise
patients who travel abroad of the im****tance of measles vaccination and
should consider the diagnosis of measles in persons with clinically
compatible illness who have traveled abroad recently or have had contact
with travelers.
The limited size of recent measles outbreaks in the United States has
resulted from highly effective measles and MMR vaccines, preexisting
high vaccination coverage levels in preschool and school-aged children,
and a rapid and effective public health response. All children should
receive 2 doses of MMR vaccine, with the first dose recommended at age
12--15 months and the second dose at age 4--6 years. Unless they have
other do***ented evidence of measles immunity,§§ all adults should
receive at least 1 dose. Two doses are recommended for international
travelers aged >12 months, health-care personnel, and students at
secondary and postsecondary educational facilities. Infants aged 6--11
months should receive 1 dose before travel abroad (3). During a measles
outbreak, the vaccination response should be guided by the epidemiology
of the outbreak and the outbreak setting and might include offering 1
dose of measles or MMR vaccine to infants aged 6--11 months, offering
the second dose to preschool-aged children provided that 28 days have
elapsed since the first dose, and recommending 1 dose to health-care
workers born before 1957 unless they show other evidence of immunity.
Patients with measles frequently seek medical care, and emergency
departments are common sites of measles transmission (4). To prevent
transmission of measles in health-care settings, patients should be
asked to wear a surgical mask (if tolerated) for source containment,
airborne infection-control precautions (5) should be followed
stringently, and patients should be placed in a negative air-pressure
room as soon as possible. If a negative air-pressure room is not
available, the patient should be placed in a room with the door closed.
Measles cases should be investigated, patients isolated promptly, and
specimens obtained for laboratory confirmation and viral genoptying.
Case contacts without do***ented evidence of measles immunity should be
vaccinated, offered immune globulin, or asked to quarantine themselves
at home from the fifth day after their first exposure to the
twenty-first day after their last exposure. Contacts with
measles-compatible symptoms should be managed in a manner that will
prevent further spread (3,5).
Health-care personnel place themselves and their patients at risk if
they are not protected against measles. In accordance with current
recommendations, health-care personnel should have do***ented evidence
of measles immunity¶¶ readily available at their work location (3). If
this do***entation is not available when measles is introduced, major
costs and disruptions to health-care operations can result from the need
to exclude potentially infected staff members and rapidly ensure
immunity for others (6).
Many of the measles cases in children in 2008 have occurred among
children whose parents claimed exemption from vaccination because of
religious or personal beliefs and in infants too young to be vaccinated.
Forty-eight states currently allow religious exemptions to school
vaccination requirements, and 21 states allow exemptions based on
personal beliefs.*** During 2002 and 2003, nonmedical exemption rates
were higher in states that easily granted exemptions than states with
medium or difficult exemption processes (7); in such states, the process
of claiming a nonmedical exemption might require less effort than
fulfilling vaccination requirements (8).
Although national vaccination levels are high,††† unvaccinated
children
tend to be clustered geographically or socially, increasing their risk
for outbreaks (6,9). An upward trend in the mean pro****tion of school
children who were not vaccinated because of personal belief exemptions
was observed from 1991 to 2004 (7). Increases in the pro****tion of
persons declining vaccination for themselves or their children might
lead to large-scale outbreaks in the United States, such as those that
have occurred in other countries (e.g., United Kingdom and Netherlands)
(10).
Ongoing measles virus transmission has been eliminated in the United
States, but the risk for im****ted disease and outbreaks remains. High
vaccination coverage in the United States has limited the spread of
im****ted measles in 2008. Nevertheless, the measles outbreaks in 2008
illustrate the risk created by im****tation of disease into clusters of
persons with low vaccination rates, both for the unvaccinated and those
who come into contact with them.
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