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California Division of Occupational Safety and Health. Heat-related illness prevention. Oakland, CA: California Division of Occupational Safety and Health; 2007. Available at http://www.dir.ca.gov/dosh/ heatillnessinfo.html. Washington State Department of Labor and Industries. Outdoor heatrelated illness (heat stress). Olympia, WA: Washington State Department of Labor and Industries; 2008. Available at http://www.Ini.wa.gov/

safety/topics/atoz/heatstress/default.asp. · CDC. Migrant farm worker dies from heat stroke while working on a

tobacco farm-North Carolina. Morgantown, WV: US Department of Health and Human Services, CDC, National Institute for Occupational Safety and Health; 2007. FACE report 2006-04. Available at http://www.cdc.gov/niosh/face/in-house/full200604.html. CDC. Criteria for a recommended standard: occupational exposure to

hot environments (revised criteria 1986). Cincinnati, OH: US -- Department of Health and Human Services, CDC, National Institute

for Occupational Safety and Health; 1986. DHHS (NIOSH) publication no. 86-113. Available at http://www.cdc.gov/niosh/86-113.html.

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Influenza Vaccination Coverage
Among Persons with Asthma

United States, 2005-06

Influenza Season During 2006, approximately 6.8 million (9.3%) U.S. ldren and 16.1 million (7.3%) U.S. adults were reported have asthma (1,2). Since 1964, the Advisory Commit

on Immunization Practices (ACIP) has recommended luenza vaccination of all persons with asthma because of !: higher risk for medical complications from influenza

those persons (3,4). Influenza vaccination coverage of rsons with asthma varies by age group and remains ow Healthy People 2010 targets of 60% coverage

of

peris aged 18–64 years with high-risk conditions (14-29c) d 90% of all persons aged 265 years (14-29a) (5–7). luenza vaccination rates of children and older adults with hma have not been well studied. Using 2006 National -alth Interview Survey (NHIS) data, this report provides · first examination of influenza vaccination rates and ated factors across a national sample of persons with hma aged 22 years. The results indicated that 36.2% ceived influenza vaccination during the 2005–06 influza season. Vaccination rates remained below target levels song all subgroups examined, including those reporting

greatest number of health-care visits in the past 12 onths. The results of this study indicate that influenza ccination coverage of all persons with asthma can be proved by increasing access to health care and using portunities for vaccination during health-care visits. NHIS is an ongoing, nationally representative, in-person usehold interview

survey

of the civilian, ninstitutionalized population of the United States.

Beginning with the 2004–05 influenza season, influenza vaccination questions were included in the child questionnaire portion of the NHIS. Because of an influenza vaccine shortage during the 2004-05 season, 2005-06 was the first influenza season for which the NHIS was able to provide an estimate of influenza vaccination rates among children with asthma in a nonshortage season. This report examines NHIS data on influenza vaccination among all persons with asthma aged 22 years during the 2004–05 and 2005–06 influenza seasons and identifies characteristics associated with vaccination coverage. Age subgroups were chosen for convenient comparison with previously published Behavioral Risk Factor Surveillance System and NHIS results (5). Because diagnoses of asthma in children aged <2 years are considered unreliable, and to be consistent with other reports, the <2 years age group was excluded from this report (6).

To ensure that included respondents had equal opportunity for vaccination, only responses for persons who were within the stated age range for the entire influenza season (September 2005-February 2006) were included; furthermore, only responses from interviews that occurred following the influenza season (i.e., interviews conducted during March-August 2006) were included in the analysis to ensure that only vaccinations given for the 2005–06 season were counted. In addition, only persons who reported the month of their most recent vaccination to be in the period September 2005-February 2006 were considered vaccinated for the 2005–06 season. The same inclusion criteria were applied to 2004–05 influenza season data.

For the 2004–05 and 2005–06 seasons, influenza vaccination status was stratified by characteristics reported to influence likelihood of vaccination, including age group, race/ethnicity, income, health insurance coverage, number of health-care visits, and possession of a usual place of health care (5,6). Differences in coverage were compared by chisquare test for within-year comparisons and z-test for comparisons in coverage across influenza seasons, with statistical significance defined as p<0.05.

Of the 15,295 survey participants aged 22 years for the entire 2005-06 influenza season, 1,277 (8.3%) reported current asthma, of whom 29 (2.2%) were excluded from further analysis because of incomplete answers regarding vaccination. Of the remaining 1,248 participants with asthma, 455 reported receiving influenza vaccinations, but 24 (5.3%) had received their vaccination before September 2005 or after February 2006 and were counted as unvaccinated for the 2005–06 season. Influenza vaccination coverage of persons aged 22 years with asthma in the 2005-06 influenza season was 36.2%, compared with

1

23.9% among those without current asthma (p<0.001) (Table 1). Both coverage rates represent significant increases from the 2004–05 season, in which respective rates were 31.5% (95% confidence interval [CI] = 28.9–34.3, p<0.05) and 16.7% (CI = 16.4-17.4, p<0.001). Among persons with asthma, those aged 50–64 years and >65 years had the highest influenza vaccination coverage in 200506 (48.6% and 75.7%, respectively). Among all age subgroups, persons with asthma were more likely to receive influenza vaccination than those without asthma (Table 1).

Persons without a usual place for health care were more likely to remain unvaccinated during the 2005–06 season (89.6%, CI = 79.3-95.1) than those with at least one usual place for health care (61.3%, CI = 57.5–65.0; p<0.001); this difference persisted when limited to the insured (81.8%, CI = 58.6-93.5; and 59.2%, CI = 55.1-63.2, respectively; p<0.03). Influenza vaccination coverage was higher among participants with health insurance coverage (39.9%) than among the uninsured (14.5%, p<0.001) (Table 2). Vaccination coverage increased from 33.8% to

39.9% (p<0.02) among insured persons with asthma for the vaccine shortage season of 2004–05 to the season regular supply in 2005–06, but coverage did not increa among those without insurance (13.5% to 14.5%, p=1.5 From the 2004–05 to the 2005–06 influenza seasons, ia cination rates increased significantly only among person in families earning annual incomes >4.5 times the fede poverty level (Table 2).

The likelihood of receiving an influenza vaccinatio increased with increasing numbers of health-care visit defined as a visit to a doctor's office, clinic, or other place health care, but not counting hospitalizations, emergens department visits, dental or home visits, or telephone cal (Table 3). Coverage ranged from 17.6% in persons with asthma reporting one visit or less to 50.8% in thos reporting 10 or more visits. Stratified by number of healthcare visits, influenza vaccination coverage was significard higher among persons with asthma than among thos without for each stratum, except for the 6–9 health-care visits stratum. Stratified by available measures of asthma

TABLE 1. Influenza vaccination coverage* levels, by asthma statust and age group - National Health Interview Survey (NHIS), S United
States, 2005-06 influenza season (September 2005-February 2006)
Age group
All persons
Without current asthma

With current asthma
(yrs)
No.1 (%)

(95% CI**)

No.
(%)
(95% CI)
No. (%)

(95% CI) 2-17 3,743 (15.9)71 (14.3–17.5) 3,332 (14.3) 7 (12.8–16.0)

411 (29.317

(23.8-35.4) 18–49 6,431 (15.2) (14.1-16.3) 5,982 (14.6) (13.5–15.7) 449 (23.6) (19.0–28.8) 50-64 2,470 (33.2) (30.9–35.6) 2,247 (31.8) (29.4–34.2)

223 (48.6) (40.0–57.4) 2,090 (65.3) (62.9-67.6) 1,955 (64.5) (62.0–67.0)

135 (75.7) (66.4-83.1) Total$$

14,991 (24.9) (23.9–25.9) 13,743 (23.9) (22.9–25.0) 1,248 (36.2) (32.7–39.9)

>65

61

54

18

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TABLE 1. (Continued) Influenza vaccination coverage* levels, by asthma statust and age group - National Health Interview Survey
(NHIS), S United States, 2005–06 influenza season (September 2005-February 2006)
Age group
With asthma and attack in past 12 mos

With asthma and ED or urgent care visit in past 12 mos (yrs)

No.
(%)
(95% CI)

No.
(%)

(95% CI) 2-17

222
(29.3)+7
(22.0–37.9)

(24.7)+7

(14.7-38.51 18–49

233
(27.9)
(21.2–35.8)

64
(30.8)

(18.5-4677 50-64

127
(49.6)
(39.1--60.2)

35
(60.9)

(37.8–79.9 >65

(80.9)
(67.4–89.7)

(88.1)

(66.4-96.5 Total$$

652
(37.5)
(32.4–42.9)

180
(41.8)

(33.2-50.9) Based on a “yes” response to either or both survey questions: “During the past 12 months, has (person) had a flu shot? A flu shot is usually given in the fall and protects against influenza for the flu season,” “During the past 12 months, has (person) had a flu vaccine sprayed in his/her nose by a doctor

or other health professional? This vaccine is usually given in the fall and protects against influenza for the flu season." + Current asthma: “Yes” responses to the survey questions "Has a doctor or other health professional ever told you that (person) had asthma?" ang

"Does (person) still have asthma?" Without current asthma: “No” response to the survey question, “Has a doctor or other health-care professional eve told you that (person) had asthma?" or "Does (person) still have asthma?” Asthma attack or episode: Yes” response to the survey question, Dunira the past 12 months, has [person) had an episode of asthma or an asthma attack?" Emergency department (ED) or urgent care visit. Yes” response

to “During the past 12 months, has (person) had to visit an emergency room or urgent care center because of asthma?" S Only responses in the subset of NHIS interviews that occurred during March-August 2006 were included to isolate responses to the 2005–15

influenza season; only persons within the stated age range for the entire influenza season (September 2005–February 2006) are included. Persos

who reported receiving vaccine before September 2005 or after February 2006 were not counted as vaccinated for the 2005–06 influenza season 1

Unweighted sample size; percentages and confidence intervals are weighted proportions.

Confidence interval. ft Within-column difference in vaccination coverage across age groups is statistically significant (p<0.001). $$ Totals are larger than the sum of rows because each age category row contains only persons within the stated age group for the entire infijerza

season (September 2005-February 2006). The broader age category of persons aged >2 years thereby includes persons who transitioned between age subgroups during the influenza season and are correspondingly not included within any one row.

3LE 2. Influenza vaccination coverage* levels among persons with current asthmat aged >2 years, by insurance status, s usual ce of care, 1 and poverty level National Health Interview Survey (NHIS),** United States, 2004–05 and 2005–06 influenza isonstt 2004–05

2005-06 aracteristic

No.$$
(%)
(95% CIM)

No.
(%)

(95% CI) ilth insurance coverage vered

1,510
(33.8)****17
(30.9–36.8)

1,069

(39.9)717 (36.0–44.0) it covered

174
(13.5)
(8.9–20.1)

176
(14.5)

(9.6–21.3) ial place for health care S

1,578
(32.8)***111 (30.0–35.8)

1,146

(38.7)717 (35.0-42.5) ).

108
(15.5)
(9.3–24.8)

102
(10.4) $$$

(4.9–20.7) io of family annual income to verty threshold II )-0.99

262
(27.1)
(20.8–34.4)

255

(25.011 (19.0–32.2) )-2.49

456
(33.1)
(28.2-38.3)

329
(34.9)

(28.2–42.4) 5–4.49

348
(28.8)
(23.8–34.4)

230
(34.5)

(26.8–43.0) >4.5

314
(28.6)** (23.1–34.8)

206
(44.5)

(36.9–52.4) Based on “yes” responses to either or both survey questions: “During the past 12 months, has (person) had a flu shot? A flu shot is usually given in the fall and protects against influenza for the flu season," "During the past 12 months, has (person) had a flu vaccine sprayed in his/her nose by a doctor or other health professional? This vaccine is usually given in the fall and protects against influenza for the flu season.” Current asthma: “Yes” responses to the survey questions, “Has a doctor or other health professional ever told you that (person) had asthma?" and “Does (person) still have asthma?" Persons aged <65 years who are not covered by private insurance, Medicaid, State Children's Health Insurance Program (SCHIP), public assistance (through 1996), state-sponsored or other government-sponsored health plans (starting in 1997), Medicare, or military plans are considered to have no health insurance coverage. Persons with only Indian Health Service coverage are considered uninsured. (CDC. Health, United States, 2006. - Available at http://www.ncbi.nlm.nih.gov/books/bookres.fcgi/healthus06/healthus06.pdf.) This pertains to overall insurance coverage and does not address whether vaccinations specifically are included in insurance. Yes: Yes” or “There is more than one place” response to the question: "Is there a place that you usually go to when you are sick or need advice about your health?" No: “There is no place” response to the same question. Only responses in the subset of NHIS interviews that occurred during March-August 2006 were included to isolate responses to the 2005–06 influenza season; only persons within the stated age range for the entire influenza season (September 2005-February 2006) are included. Persons who reported receiving vaccine before September 2005 or after February 2006 were not counted as vaccinated for the 2005–06 influenza season. The same criteria were applied to the 2004-05 season. Respectively, September 2004-February 2005 September 2005-February 2006. Unweighted sample size; percentages and confidence intervals are weighted proportions. Confidence interval. Difference in across-year comparison within stratification is statistically significant (p<0.05). Difference among within-year stratification is statistically significant (p<0.05). Estimate is considered unreliable and should be interpreted with caution: relative standard error = 0.3-0.5. Missing income responses were not imputed or included.

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(12.0)91

(17.6) 19-**

BLE 3. Influenza vaccination coverage* levels among persons aged >2 years by current asthma statust and number of health-care its, National Health Interview Survey (NHIS)|| — United States, 2005-06 influenza season** - healthAll persons Without asthma

With asthma tre visits No.tt (%)

(95% CIS)

No.
(%)
(95% CI)

No.
(%)

(95% CI)
5,608 (12.3) 11 (11.3–13.4) 5,346

(11.0–13.1) 262

(13.0–23.4) i 6,036 (28.6) (27.0–30.2) 5,522 (27.9)*** (26.3–29.6)

514 (36.1)*** (30.8–41.7) ) 1,409 (38.5) (35.4–41.8) 1,240 (38.1) (34.8–41.4)

169 (41.9) (32.8–51.5) )

1,850 (40.7) (38.1-43.5) 1,562 (39.0)*** (36.0-42.1) 288 (50.8)*** (43.2-58.3) - Based on “yes” responses to either or both survey questions: “During the past 12 months, has (person) had a flu shot? A flu shot is usually given in the fall and protects against influenza for the flu season,” “During the past 12 months, has (person) had a flu vaccine sprayed in his/her nose by a doctor or other health professional? This vaccine is usually given in the fall and protects against influenza for the flu season."

Current asthma: Yes” responses to the survey questions, “Has a doctor or other health professional ever told you that (person) had asthma?" and | “Yes” response to the survey question, “Does (person) still have asthma?” Without current asthma: “No” response to the survey question, "Has a

doctor or other health-care professional ever told you that (person) had asthma?" or "Does (person) still have asthma?" - Based on response to the question: "During the past 12 months, how many times have you seen a doctor or other health-care professional about your * own health at a doctor's office, a clinic, or some other place? Do not include times you were hospitalized overnight, visits to hospital emergency rooms, home visits, dental visits, or telephone calls." Only responses in the subset of NHIS interviews that occurred during March-August 2006 were included to isolate responses to the 2005–06 influenza season; only persons within the stated age range for the entire influenza season are included. Persons who reported receiving vaccine outside of September 2005-February 2006 were not counted as vaccinated for the 2005–06 influenza season. September 2005-February 2006. Unweighted sample size; percentages and confidence intervals are weighted proportions. Confidence interval. Difference in vaccination coverage among health-care visits subgroups was statistically significant (p<0.05). Pairwise difference between “with na" and "without asthma" wit the given health-care visits subgroup was statistically significant (p<0.05).

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severity, coverage was not different among those with acute exacerbations. Vaccination

coverage
was 41.8%

among persons with at least one emergency department or urgent care visit for asthma within the preceding 12 months and 35.4% with no such visits (p=0.2). Influenza vaccination coverage did not differ significantly between persons with asthma who had an exacerbation in the past 12 months and those who did not (37.5% versus 34.8%, p=0.5). Vaccination coverage also did not differ significantly by race/ ethnicity, ranging from 30.8% of Hispanics (CI = 24.438.1) to 37.9% (CI = 33.4–42.5) of non-Hispanic whites (p=0.09). Reported by: CB Ligon, RA Rudd, MSPH, DB Callahan, MD, Div of Environmental Hazards and Health Effects, National Center for Environmental Health; GL Euler, DrPH, Immunization Sves Div, National Center for Immunization and Respiratory Diseases, CDC Editorial Note: This report presents the first estimates of influenza vaccination coverage in the United States among the civilian, noninstitutionalized population of persons with asthma and reinforces the need to increase vaccination throughout this at-risk population. Health-care visits provide an opportunity for vaccination, but even among persons with the highest number of visits, nearly half remained unvaccinated in the 2005–06 influenza season. Even so, access to health care is an important factor associated with receiving influenza vaccination. Persons with asthma who had health insurance had a greater rate of influenza vaccination than did those who lacked insurance. Likewise, the vaccination rate for persons with asthma who had a usual place for health care was significantly greater than the rate for those who did not have a regular place for health care. After the vaccine shortage of the 2004–05 influenza season, vaccination coverage of persons with asthma in 200506 failed to improve among households with the lowest incomes, among persons without health insurance, and among persons without a regular place for medical care, emphasizing the need for interventions that include the medically underserved.

During the 2005–06 influenza season, the oldest age groups (50–64 years and >65 years) had the highest vaccination coverage. Influenza vaccination is recommended for both age groups, regardless of asthma status, because the influenza-related death rate increases sharply among older adults (3). In February 2006, ACIP recommended that all children aged 24–59 months be vaccinated against influenza, regardless of risk status. Examination of the 2007 NHIS data could determine whether the expanded recommendation affected coverage among the subset of children with asthma, who already had been recommended for vaccination under previous guidelines. Because ACIP voted in

February 2008 to recommend influenza vaccination for children, data soon will be available to also study th effects on coverage for older children.*

The findings in this report are subject to at least the limitations. First, the sample size of the survey (34,12 adults and children, 2,700 of whom reported having car rent asthma) limits reliable identification of patterns amor subgroups of persons with asthma potentially of intere : but smaller in number than the subgroups examined here Second, determination of vaccination status in NHIS IS made by self-report, which introduces recall bias and like overestimation of vaccination rates (8). Finally, NHIS doo not ascertain whether a child received a second vaccine dost as is recommended by ACIP for children aged 6 months to 8 years who previously have not received the influenza vaccination; therefore, NHIS overestimates full coverage to: this age group (3).

The findings in this report emphasize the need for measures to uniformly increase influenza vaccination rates among persons with asthma. Interventions that target patients, health-care access, and health-care providers have demonstrated benefits in similar settings and should be implemented to improve influenza vaccination coverage. Such interventions include automated reminders, standing orders, multicomponent educational programs,

reduc tion of travel distances or out-of-pocket vaccine costs, and provider performance feedback (9). Persons with inadequate access to health care and those treated at multiple facilities would be less likely to miss opportunities for vaccination if they consistently sought care at a single medical faciliy That continuity of care could reduce the diffusion of responsibility that occurs when patients are treated at multiple health-care facilities (10). Providing vaccinatior through at least January and February of the influenza sezson can further reduce missed opportunities for effective vaccination of persons in this group at high risk. References 1. Bloom B, Cohen RA. Summary health statistics for U.S. children

National Health Interview Survey, 2006. Vital Health Siar

2007;10(234). 2. Pleis JR, Lethbridge-Çejku M. Summary health statistics for 1.)

adults: National Health Interview Survey, 2006. Vital Health Su

2007;10(235). 3. CDC. Prevention and control of influenza: recommendations of the

Advisory Committee on Immunization Practices (ACIP), 204

MMWR 2007;56(No. RR-6). 4. CDC. Advisory Committee on Immunization Practices: recommen

dations for influenza immunization and control in the civilian poput tion. Influenza Surveillance Report 1964;80:8-11.

* Available at http://www.cdc.gov/vaccines/recs/provisional/downloads'tla-3" 08-508.pdf.

CDC. Self-reported influenza vaccination coverage trends 1989–2006 among adults by age group, risk group, racelethnicity, health-care worker status, and pregnancy status, United States, National Health Interview Survey (NHIS). Available at http://www.cdc.gov/flu/

professionals/vaccination/pdf/vaccinetrend.pdf. .. CDC. Influenza vaccination coverage among children with asthma

United States, 2004–05 influenza season. MMWR 2007;56:193-6. . US Department of Health and Human Services. Healthy people 2010 (conference ed, in 2 vols). Washington, DC: US Department of Health and Human Services; 2000. Available at http://www.healthypeople.gov. Mangtani P, Shah A, Roberts JA. Validation of influenza and pneumo

coccal vaccine status in adults based on self-report. Epidemiol Infect 1. 2007;135:139–43. ... Task Force on Community Preventive Services. Recommendations

regarding interventions to improve vaccination coverage in children, adolescents, and adults. Am J Prev Med 2000;18(1 Suppl):92–6. Smith PJ, Santoli JM, Chu SY, Ochoa DQ, Rodewald LE. The association between having a medical home and vaccination coverage among children eligible for the Vaccines for Children program. Pediatrics 2005;116:130–9.

that 1) although serum-based diagnostics remain the “gold standard,” the use of these two alternative sampling techniques would not adversely affect routine measles and rubella surveillance and might enhance surveillance; 2) regions in the elimination phase* that already have established serum-based testing for rash illness surveillance would not likely benefit from converting to DBS or OF sampling methods, except in special circumstances; and 3) DBS or Of sampling are viable options for measles and rubella surveillance in all regions, especially where patients might resist venipuncture for blood collection, or where special challenges exist with transport or refrigeration of diagnostic samples.

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Recommendations from an Ad Hoc Meeting of the WHO Measles and

Rubella Laboratory Network (LabNet) on Use of Alternative Diagnostic Samples for Measles

and Rubella Surveillance Laboratory confirmation of measles and rubella is an iportant component of disease surveillance in all settings. cause the use of clinical diagnosis for surveillance is unliable, case-based laboratory confirmation of disease is itically important in settings with measles or rubella elimiition goals. The World Health Organization (WHO) easles and Rubella Laboratory Network (LabNet) was tablished in 2000 to provide a standardized testing and porting structure and a comprehensive, external qualitysurance program (1). LabNet currently consists of 679 boratories serving 166 countries. However, measles and bella surveillance remains incomplete in certain areas cause of difficulties with the collection and transport of rum specimens. Recently, LabNet evaluated two alternale sampling approaches to serum samples, the use of dried ood spots (DBS) and oral fluid (OF) samples. Both of ese approaches have potential to be useful tools for measles d rubella control programs. In June 2007, WHO conned an ad hoc meeting in Geneva, Switzerland, to review ailable data and provide recommendations on use of DBS d OF samples for measles and rubella diagnostics. tendees included LabNet staff members and scientists 10 had been conducting studies to evaluate use of these ernative diagnostic samples. The attendees concluded

Background on Use of Alternative
Diagnostic Samples

Conventional laboratory confirmation of suspected cases of measles and rubella is based on the detection of virusspecific immunoglobulin M (IgM) in a single serum sample collected soon after the onset of symptoms (2). In addition, detection of viral RNA by reverse transcriptionpolymerase chain reaction (RT-PCR), usually in a throat swab or urine sample, and subsequent genotyping of strains is valuable for diagnosis and molecular epidemiology (2). Accurate laboratory results for detection of IgM and viral RNA are dependent on proper collection, processing, shipment, and storage of clinical samples and use of accurate tests performed by a proficient laboratory. However, collection of blood samples by venipuncture, particularly from children, can be a challenge, and the sustained refrigeration required for diagnostic samples during transport is not always achievable. In these situations, alternatives to serum collection can be useful.

DBS has been used for various epidemiologic studies for the detection of measles- and rubella-specific IgG and IgM antibodies and viral RNA (3–5). Antibody and viral RNA are sufficiently stable on DBS at <98.6°F (<37.0°C) to allow this sample collection method to be used for case confirmation or molecular epidemiology in areas where sample refrigeration is not feasible. OF has been used in similar studies and for the national measles, mumps, and rubella (MMR) surveillance program in the United Kingdom (UK) for approximately 10 years (6,7). OF is easy to

* As of 2008, four out of six World Health Organization regions have measles elimination goals: the Region of the Americas (by 2000; measles declared eliminated since late 2002), the European Region (by 2010), the Eastern Mediterranean Region (by 2010), and the Western Pacific Region (by 2012). In addition, two regions have rubella elimination goals: the Region of the Americas and the European Region (both by 2010).

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