CDC ILI surveillance case definition: fever (100oF ), plus cough, sore throat, or both in the absence of another known cause of illness. Vol. 58 / No. 37 MMWR 1031 - By real-time reverse transcription-polymerase chain reaction assay; all patients tested negative for seasonal influenza.  Remel Xpect Flu A&B test (Remel Products, Lenexa, Kansas). TABLE. Performance of a rapid influenza detection test (RIDT)- in patients with suspected and confirmed  2009 pandemic influenza A (H1N1) virus infection, by clinical syndrome consistent with CDC-defined influenza-like illness (ILI)  -Connecticut, 2009 rRT-PCR positive rRT-PCR negative Total RIDT positive RIDT negative RIDT positive RIDT negative Sensitivity % Specificity % PPV  % NPV % Overall 63 23 26 2 12 47 86 92 32 CDC-defined ILI 48 19 21 1 7 48 88 95 25 No CDC-defined ILI 15 4 5 1 5 44 83 80 50 - Remel Xpect Flu A&B test (Remel Products, Lenexa, Kansas).  By real-time reverse transcription-polymerase chain reaction (rRT-PCR); all patients tested negative for seasonal influenza.  CDC ILI surveillance case definition: fever (100F ) plus cough, sore throat, or both in the absence of another known cause of illness.  Positive predictive value.  Negative predictive value.#
During May 2009, a few weeks after 2009 pandemic influenza A (H1N1) infection was first detected in the United States (1), outbreaks among students from two schools were detected in Greenwich, Connecticut. Staff members from Greenwich Hospital and the Connecticut Department of Public Health collected data on symptoms for 63 patients and submitted nasopharyngeal washings for testing using a rapid influenza diagnostic test (RIDT) for influenza A and B and real-time reverse transcription-polymerase chain reaction (rRT-PCR) assay, thereby affording an opportunity to assess the field performance of the RIDT. A total of 49 patients had infections with pandemic influenza A (H1N1) confirmed by rRT-PCR. This report summarizes the findings from this performance assessment, which indicated that, compared with rRT-PCR, the sensitivity of the RIDT for detecting infection in patients with 2009 pandemic influenza A (H1N1) was 47%, and the specificity was 86%. Sensitivity and specificity did not vary substantially by the presence or absence of CDC-defined influenza-like illness (ILI) or by time from symptom onset to specimen acquisition. In this group of patients, although positive RIDT results performed well in predicting confirmed infection with pandemic H1N1 virus (positive predictive value: 92%), negative tests did not accurately predict the absence of infection (negative predictive value: 32%). These results affirm recent CDC recommendations against using negative RIDT results for management of patients with possible 2009 pandemic influenza A (H1N1) infection (2).
During April 29-May 1, 2009, 78 students from a private school (school A) near Greenwich, Connecticut, participated in a class trip to Pennsylvania. Several students became sick with a respiratory illness. Because infection with 2009 pandemic influenza A (H1N1) was suspected, upon returning home, 11 of the students, a sibling, and two other students went to the Greenwich Hospital for outpatient influenza testing and treatment.
During May 18-20, 133 students and eight teachers from a public school (school B) in Greenwich traveled to a camp in Connecticut. Among these students, 36 visited the camp infirmary with fever, headache, or fatigue. The Greenwich Health Department asked physicians at the hospital to assist with testing the students for pandemic H1N1. A total of 67 students and staff from school B became ill, and 49 of these patients went to the hospital for influenza testing.
A total of 63 patients (14 students from school A and 49 students and staff from school B) were tested for influenza at the hospital. A standard symptom survey was completed by a physician for each patient after which a nasopharyngeal washing was performed by an experienced respiratory therapist trained in the procedure. All samples were placed in viral transport media and sent to the Connecticut Department of Public Health laboratory for influenza virus detection by rRT-PCR. Rapid screening for influenza A and B was performed concurrently at the hospital laboratory using the Remel Xpect Flu A&B test (Remel Products, Lenexa, Kansas) according to manufacturer's instructions (3). Although the number of ill persons who eventually received antiviral therapy is unknown, all nasopharyngeal washings were obtained before initiation of therapy.
Of the 63 patients tested by RIDT, 49 patients, 11 (79%) from school A and 38 (78%) from school B, were found to have 2009 pandemic influenza A (H1N1) infection by rRT-PCR (Figure). Of the 49 patients with confirmed infection, 23 (47%) tested positive (eight from school A and 15 from school B) and 26 (53%) tested negative for 2009 pandemic influenza A (H1N1) by RIDT. Among 11 patients with positive rRT-PCR tests from school A and 38 from school B, the numbers of positive RIDT tests were 8 (73%) and 15 (39%) respectively.
Among the 14 patient samples from both schools that tested negative by rRT-PCR, three were from students at school A, and 11 were from school B. Of the 14 rRT-PCR negative specimens, two tested positive by RIDT (one from school A and one from school B). The overall sensitivity of the RIDT was 23 of 49 (47%), and the specificity was 12 of 14 (86%). The positive predictive value was 23 of 25 (92%), and the negative predictive value was 12 of 38 (32%).
The schools did not differ significantly with respect to percentage of patients with confirmed pandemic H1N1 by rRT-PCR, severity of symptoms, interval between the onset of symptoms and collection of specimens for testing, or overall RIDT positivity rate. Among all the patients tested by RIDT, no significant differences between true positives and false negatives were seen with respect to ILI.- In RIDT positive and RIDT negative patients with pandemic H1N1, the median interval from symptom onset to specimen collection was 36 hours. Of the 34 patients with washings obtained 36 hours from the onset of symptoms, 16 (47%) were RIDT positive; of the 15 patients with washings collected after 36 hours of symptoms, seven (47%) were positive. RIDT test performance was assessed for patients with and without CDC-defined ILI (Table ). The sensitivity and specificity were approximately the same for the two groups (48% versus 44% and 88% versus 83%, respectively). Editorial Note: When cases of 2009 pandemic influenza A (H1N1) began appearing in the United States in April 2009, several RIDTs had been in common use in the United States as point-of-care tests for seasonal influenza, but the performance of these tests in patients infected with 2009 pandemic influenza A (H1N1) virus was unknown. CDC has since reported varying sensitivities of RIDTs in retrospective analyses of rRT-PCR positive respiratory samples, from 40%-69%. In these analyses, RIDT sensitivity was positively associated with the titer of virus in the sample (4).
The analysis in this report of pandemic H1N1 cases at two schools determined that the RIDT used detected less than half the cases confirmed by rRT-PCR. The low sensitivity and low negative predictive value of the test during these outbreaks highlight the limitations of using this test alone to establish diagnosis and aid clinical management. These results affirm current recommendations not to use negative RIDT results to rule out pandemic H1N1 or to make infection control decisions (2). Rapid tests differ in their sensitivity and specificity for detecting seasonal influenza in respiratory specimens but generally have low to moderate sensitivity compared with viral culture or rRT-PCR. Previous RIDT studies have described the performance of the QuickVue Influenza A+B test (Quidel Corporation, San Diego, California) for detecting seasonal influenza in three different populations during 2008. Sensitivity when compared with rRT-PCR was low for all populations (median: 27%; range: 19%-32%) (5).
The RIDT used in the current study has a reported sensitivity of 92.5% and a specificity of 100% for the diagnosis of seasonal influenza A by nasopharyngeal wash (3). This investigation yielded much lower sensitivity (47%) and specificity (86%) in patients having confirmed infection with 2009 pandemic influenza A (H1N1) virus.
The findings in this report are comparable to recently reported observations of low performance of RIDTs in patients with pandemic H1N1. In a report of hospitalized patients in California, rapid antigen test results were positive in 67% of cases of pandemic H1N1 tested (6). In an assessment of rapid testing compared with rRT-PCR conducted on 6,090 patient samples from the New York City area, the sensitivity and specificity for the detection of 2009 pandemic influenza A (H1N1) virus by rapid antigen testing, using the BinaxNOW Influenza A&B test (Binax, Inc., Scarborough, Maine) and the 3M Rapid Detection Flu A+B test (3M, St. Paul, Minnesota) were 17.8% and 93.6% respectively (7). A recent report from the Naval Health Research Center described screening 3,066 clinical samples from service personal with influenza-like illness; of those screened, 767 rapid test results by QuickVue Influenza A+B test were available for comparison with rRT-PCR results (8). Of 39 patients with pandemic H1N1, 20 were RIDT positive, with a 51% sensitivity; for seasonal influenza A the sensitivity was 63% for H1N1 and 31% for H3N2. Specificity was 99% for all three subtypes when compared with rRT-PCR.
The results of these studies and the findings in this report affirm that a negative result for this rapid test does not rule out 2009 pandemic influenza A (H1N1) virus infection in an individual with symptoms consistent with influenza. Factors that might decrease the performance of rapid influenza antigen tests include improper specimen collection, not testing the recommended clinical sample (e.g., nasal versus nasopharyngeal swab), quality of the specimen, prolonged time from illness onset to specimen collection (because viral shedding decreases over time), and improper handling and storage of the specimen before testing. The reason for the suboptimal detection of 2009 pandemic influenza A (H1N1) by the RIDT used in this study was not specifically determined but did not appear to be related to differences in the interval (median: 36 hours for both groups) from onset of symptoms to specimen collection or to the severity of symptoms. As with all screening tests, the positive and negative predictive values of RIDTs are dependent on the prevalence of the disease in the population.
The findings in this report are subject to at least one limitation. The assessment involved a limited number of patients from two small outbreaks. The results should be viewed in this context. In other field situations (e.g., with other disease prevalences, collection and transport methods, or using other RIDTs), RIDTs might have different performance characteristics.
RIDTs can be an important tool for patient care during the normal influenza season because they usually provide results within 30 minutes. In addition, these tests can be used to make decisions about isolating or cohorting patients in health-care settings and recommending or restricting patient movements in outpatient settings. They might be especially important for hospitals limited by the expense of rRT-PCR and in identifying influenza during outbreaks in defined patient groups, such as those in schools or nursing homes. However, if used for management of patients with possible pandemic H1N1 virus infection, false-negative test reports might result in inappropriate exposure of susceptible persons to infected patients. Additional large studies to better characterize the performance of RIDTs for detection of infection in patients with pandemic H1N1 virus and improvements in rapid testing for pandemic H1N1 are needed.

# Anaplasmosis and Ehrlichiosis -Maine, 2008
Anaplasmosis and ehrlichiosis are rickettsial tickborne diseases that have had at least a twofold increase in prevalence in the United States since 2000 (1,2). Despite similar clinical presentations, the causative organisms are carried by different ticks with distinct geographic and ecologic associations (3). Surveillance efforts are complicated by ambiguous terminology and serologic testing with antibody cross-reactivity. Although anaplasmosis historically has been reported in Maine, ehrlichiosis has been reported infrequently. During 2007-2008, the number of physician-reported anaplasmosis cases nearly doubled in Maine, and ehrlichiosis cases increased more than fourfold. To examine this increase, the Maine Department of Health and Human Services (MDHHS) analyzed available data on tick burden and physician-reported cases of anaplasmosis and ehrlichiosis during 2000-2008. This report describes the results of that analysis, which indicated that Ixodes scapularis (the tick vector for Anaplasma phagocytophilum) was broadly distributed in Maine, whereas Amblyomma americanum (the tick vector for Erhlichia chaffeenisis) was scarce. Moreover, 95% of physician-reported ehrlichiosis cases lacked a concurrent serologic assessment to exclude anaplasmosis, suggesting that antibody cross-reactivity might have resulted in misclassification. In 2008, Maine modified case classification to enhance specificity; ehrlichiosis cases that lack a concurrent test for anaplasmosis are now classified as suspect rather than probable and therefore are not included in national surveillance summaries. The accuracy of case classification and surveillance can be improved by educating health-care providers regarding 1) the expected geographic distribution of tick vectors and 2) recommendations for confirmatory testing to distinguish between the causative organisms of anaplasmosis and ehrlichiosis.
In Maine, laboratories electronically report positive anaplasmosis and ehrlichiosis results to the health department (referred to as physician reported). Field epidemiology personnel follow up positive results by interviewing physicians and patients and by obtaining clinical, laboratory, and epidemiologic information required to complete the CDC tickborne rickettsial disease case report form.- MDHHS conducted a review of available data on tick burden in the state and reviewed the clinical and public health surveillance data for physician-reported human ehrlichiosis and anaplasmosis during 2000-2008. Maine classified cases according to Council of State and Territorial Epidemiologists (CSTE) case definition  with the exception that the 2008 cases were classified according to a modified ehrlichiosis case definition that had increased specificity.

# Tick Surveillance Data
During 2000-2008, the Vector Borne Disease Laboratory of the Maine Medical Center Research Institute conducted active surveillance of ticks in Maine (through flagging and trapping) and passive surveillance (through receipt of ticks submitted by state residents through the mail) (4). A total of 5,089 I. scapularis were collected, but only 15 A. americanum ticks were detected. All life stages of I. scapularis (larvae, nymphs, and adults) were identified; the tick distribution increased and expanded along the southern coastline and up the river valleys, corresponding to areas of increasing settlement of human populations in this geographic distribution. During 2007-2008, Maine residents submitted 1,968 I. scapularis and only six A. americanum. The surveillance results suggested that A. americanum, the ehrlichiosis vector, had only a sparse and sporadic distribution in Maine.

# Human Anaplasmosis Surveillance Data
During 2000-2008, a total of 45 cases of anaplasmosis cases were reported in Maine. Fifteen (33%) cases were confirmed, 30 (67%) were probable, and no suspect cases were reported (Tables 1 and 2). Among the 15 confirmed cases, three (20%) patients were diagnosed by demonstration in paired sera of a fourfold or greater increase in antibodies to A. phagocytophilum in acute versus convalescent samples; 12 (80%) patients were diagnosed by polmerase chain reaction (PCR) detection of A. phagocytophilum DNA, including two patients who also had positive single A. phagocytophilum serologic test. Among the 30 probable cases, 23 (77%) patients were diagnosed only by a single test for antibodies to A. phagocytophilum, including one (3%) patient who also had detection of morulae consistent with A. phagocytophilum on a blood smear. Seven (23%) patients were tested for antibodies to both A. phagocytophilum and E. chaffeensis, and all showed higher antibody titers to A. phagocytophilum. The median patient age among all confirmed and probable cases was 57 years (range: 21-89 years); 28 patients (62%) were males. Seventeen (38%) patients were hospitalized, and one (2%) patient died from renal failure relating to infection. Two (4%) patients were diagnosed with concurrent Lyme disease, and two (4%) with concurrent babesiosis. Reported anaplasmosis cases occurred during April-December; 30 (67%) of 45 patients had onset dates during May-September. Anaplasmosis was reported in six (38%) of 16 counties; the majority occurred in southern coastal Maine. One patient with confirmed anaplasmosis had traveled to New York, an anaplasmosis-endemic state, during the preceding month.

# MMWR September 25, 2009
Human Ehrlichiosis Surveillance Data
During 2000-2008, a total of cases of ehrlichiosis were reported in Maine (Tables 1 and 2). The single confirmed case, which was diagnosed by PCR, occurred in a male aged 58 years who worked as an interstate truck driver; therefore, outof-state exposure to E. chaffeensis was possible. An additional 19 ehrlichiosis cases were reported during this same period (including six cases reported during 2005-2007 and 13 cases reported during 2008). All 19 cases were diagnosed by a single positive Ehrlichia serologic assay, and none had accompanying serologic tests to exclude anaplasmosis. Although all 13 cases reported in 2008 would have met the CSTE case definition for probable ehrlichiosis, beginning in that year, Maine had adopted a modified ehrlichiosis case definition to increase specificity; therefore, these 13 case were classified as suspect. Ten of the 20 cases were in persons who had either concurrent Lyme disease (seven persons) or babesiosis (three persons), which, like Anaplasma, are transmitted by I. scapularis.

# Classification of Ehrlichiosis Cases
Based on the lack of evidence for a sustained tick vector population in the state, lack of travel history among patients, and the cross-reactive serologic tests for ehrlichiosis and anaplasmosis, MDHHS implemented a new ehrlichiosis case classification strategy using a modified CSTE case definition in 2008 (5). Probable ehrlichiosis cases were defined as clinically compatible with one positive immunoglobulin G (IgG) serologic result for E. chaffeensis and either a concurrent lower titer serologic test for A. phagocytophilum or visualization of intracytoplasmic morulae in peripheral monocytes or macrophages. For cases having serologic reactivity to both agents, the higher antibody level was used to identify the most likely infection (5). Ehrlichiosis reports that did not meet this new more stringent probable case definition (i.e., those that were only tested for ehrlichiosis) were classified as suspect cases, which are excluded from national notifiable disease surveillance summaries.
Editorial Note: The findings in this report underscore that the use of cross-reactive serologic assays, which test for ehrlichiosis alone in anaplasmosis-endemic areas, can result in an inaccurately high ehrlichiosis incidence and contribute to underrecognition of actual anaplasmosis cases. Serologic assays for A. phagocytophilum and E. chaffeensis have >50% cross reactiv-ity; thus, differentiating between ehrlichiosis or anaplasmosis based on single serologic assay is not possible (6)(7)(8). In 2008, Maine classified 13 ehrlichiosis cases as suspect because they more likely represent infection with A. phagocytophilum given that tick data did not support a sustained ehrlichiosis vector in the state and confirmatory laboratory testing and supporting travel history for ehrlichiosis infection were lacking. The likelihood these suspect cases are anaplasmosis cases is further supported by the fact that 54% of suspect ehrlichiosis cases occurred in persons who had either concurrent Lyme disease or babesiosis, which, like Anaplasma, are transmitted by I. scapularis. Whether the emergence of anaplasmosis in Maine and nationwide is an actual increase in incidence or an increase in awareness and testing is unclear. Reports of anaplasmosis have increased threefold (from 351 cases in 2000 to 1,053 cases in 2008), and reports of ehrlichiosis have increased more than fourfold (from 200 cases in 2000 to approximately 800 cases in 2008) (1; CDC, unpublished data, 2009). Most cases of ehrlichiosis have been reported from the southern and south-central United States, corresponding to the geographic distribution of the tick vector, A. americanum. However, during 2008-2009, a concerning trend of increased ehrlichiosis case reports from some northern-area states, including Maine, has been noted (CDC, unpublished data, 2009). Possible explanations for this increase include expanding geographic ranges of the tick vector A. americanum or misclassification of cases.
Anaplasmosis, referred to as human granulocytic anaplasmosis, is caused by A. phagocytophilum. Before a taxonomic reorganization in 2001, this organism was called Ehrlichia phagocytophilum, and the infection was described as human granulocytic ehrlichiosis. I. scapularis (the black-legged tick), the vector for anaplasmosis, is reported commonly from northern and northeastern states. Ehrlichiosis, known as human monocytic ehrlichiosis, is caused by E. chaffeensis and is transmitted by A. americanum (the lone star tick). E. chaffeensis is commonly reported in the southern and south-central states, where the vector is common. Both anaplasmosis and ehrlichiosis are nationally notifiable diseases. In Maine, the vector A. americanum responsible for transmission of E. chaffeensis is not endemic. Conversely, A. phagocytophilum DNA has been detected in 16% of 94 I. scapularis ticks tested in 2008 (9). The fact that 95% of physician-reported ehrlichiosis cases lacked a concurrent serologic assessment to exclude anaplasmosis supports the likelihood that antibody cross-reactivity could have resulted in misclassification. One factor contributing to this misclassification might have been confusion among physicians regarding the recent change in terminology for A. phagocytophilum infection (from human granulocytic ehrlichiosis to anaplasmosis) and a lack of understanding of appropriate testing strategies. Since taxonomic changes were adopted in 2001, the term "anaplasmosis" has gradually replaced the term "human granulocytic ehrlichiosis" to describe human infections with A. phagocytophilum. However, some medical references and commercial test names still use the term "ehrlichiosis," which might cause confusion among physicians regarding the selection of appropriate diagnostic tests.
Health-care providers should assess clinical and ecologic features and, as indicated, include concurrent confirmatory testing for both anaplasmosis and ehrlichiosis or other tickborne diseases when evaluating patients with suspected tickborne illness. Compared with anaplasmosis patients, ehrlichiosis patients might have a higher potential for severe or fatal outcome, and a higher proportion (up to 30%) of ehrlichiosis patients have rash; thus, these diagnostic clues also can prompt physicians to request concurrent testing for ehrlichiosis (3). If serologic testing is selected to evaluate patients, serology should include 1) concurrent testing for both A. phagocytophilum and E. chaffeensis and 2) testing of paired acute and convalescent sera whenever possible. PCR is considered a confirmatory test and is the recommended diagnostic tool preferred over serology because it can differentiate between the two infections (4,10). Patients with suspected anaplasmosis or ehrlichiosis should be treated promptly with doxycycline, without regard to initial serologic test results, because antibodies in the first week of illness frequently are not detected.  Seven patients were tested for antibodies to both A. phagocytophilum and E. chaffeensis concurrently, and all showed higher antibody titers to A. phagocytophilum.  Diagnosed by demonstration in paired sera of a fourfold or greater increase in antibodies to A. phagocytophilum in acute versus convalescent samples.  Polymerase chain reaction.   Visualization of intracytoplasmic morulae in granulocytes for anaplasmosis or peripheral monocytes or macrophages for ehrlichiosis.

# MMWR September 25, 2009

# Progress Toward Measles Control -African Region, 2001-2008
In 2001, the countries of the World Health Organization (WHO) African Region (AFR) became part of a global initiative with a goal of reducing the number of measles deaths by 50% by 2005, compared with 1999. Recommended strategies for measles mortality reduction included 1) increasing rou-increasing routine coverage for the first dose of measles-containing vaccine (MCV1) for all children, 2) providing a second opportunity for measles vaccination through supplemental immunization activities (SIAs), 3) improving measles case management, and 4) establishing case-based surveillance with laboratory confirmation of all suspected measles cases (1). Before introduction of MCV throughout AFR, approximately 1 million measles cases had been reported each year in the early 1980s (2). After strengthening measles-control activities, annual reported cases declined to an estimated 300,000-580,000 during the 1990s.  (3,4). However, inaccuracies in reported vaccination coverage exist, surveillance is suboptimal, and measles outbreaks continue to occur in AFR countries. Further progress in measles control will require full implementation of recommended strategies, including validation of vaccination coverage.
Since the 1980s, AFR countries have reported measles vaccination coverage and the number of measles cases each year to the WHO African Regional Office (AFRO), using the WHO and United Nations Children's Fund (UNICEF) Joint Reporting Form. These data are collected through administrative reports from routine vaccination programs and SIAs and routine surveillance systems that provide aggregated case counts based on clinical diagnosis. Estimates of routine coverage with MCV1 are based on review of coverage data from administrative records, surveys, national reports, and consultation with local and regional experts. Coverage achieved during nationwide SIAs against measles are reported on the basis of the reported number of doses administered, divided by the target population.
In 1999, as part of the measles mortality reduction strategy, case-based surveillance with laboratory testing for all suspected measles cases was introduced with support from WHO AFRO. A suspected measles case is defined as 1) any person with generalized maculo-papular rash and fever plus cough or coryza or conjunctivitis or 2) any person in whom a clinician suspects measles. Each suspected measles case should be reported using an individual case-investigation form, and a blood specimen should be collected and sent to the laboratory for measles-specific immunoglobulin M testing. Laboratory confirmation of individual cases is discontinued after an outbreak has been confirmed as measles. An outbreak is confirmed when three or more measles laboratory-confirmed cases are detected in a health facility or district in 1 month; subsequent cases are confirmed by epidemiologic link. An epidemiologic link is defined as a suspected measles case that did not have a specimen collected for laboratory testing and is linked in person, place, and time to a laboratory-confirmed case (i.e., in a patient living in the same district or an adjacent district with a patient with laboratory-confirmed measles where a likelihood of transmission and onset of rash in the two patients within 30 days of each other exists) (5). Case-based surveillance data from AFR countries are shared regularly with WHO AFRO. Data quality is monitored using annualized performance indicators that include the 1) percentage of districts reporting one or more suspected case with a blood specimen (target: >80%) and 2) nonmeasles febrile rash illness rate (target: >2 cases per 100,000).

# Routine Vaccination Activities
In AFR, MCV1 is administered through routine services to children at age 9 months. According to WHO and UNICEF estimates, AFR MCV1 coverage increased from 57% in 2001 to 73% in 2008 (Figure). In 2008, among the 46 AFR countries,- three (7%) had MCV1 coverage of <60%, 13 (28%) had coverage of 60%-69%, 11 (24%) had coverage of 70-79%, 10 (22%) had coverage of 80-89%, and nine (20%) had coverage of 90% (Table 1

# SIA Results
SIAs provide a second opportunity for measles immunization to all children, including those not vaccinated with MCV1 and those previously vaccinated; approximately 15% of children vaccinated with a single dose at age 9 months will not develop immunity to measles. The SIA strategy generally consists of a one-time catch-up SIA, targeted to a wide age range, which aims to reduce susceptibility to measles in the population. This is followed by periodic follow-up SIAs targeting children born since the last SIA, thus reducing the accumulation of susceptible children in new birth cohorts.
Before 2000, seven (15%) AFR countries (Botswana, Lesotho, Malawi, Namibia, South Africa, Swaziland, and Zimbabwe) had completed a catch-up SIA, and Namibia and South Africa had completed a follow-up SIA (6). By the end of 2008, 43 AFR countries (all except Algeria, Mauritius, and Seychelles) had completed a catch-up SIA, and all but Comoros and Guinea-Bissau had completed at least one follow-up SIA (Table 2

# Measles Surveillance
By December 2008, all AFR countries except Algeria, Comoros, Guinea Bissau, Mauritius, Sao Tome & Principe, and Seychelles had established measles case-based surveillance in accordance with the WHO AFRO measles surveillance guidelines (5). In 2008, of the 40 countries with case-based surveillance, 21 (53%) met the target of >80% of districts reporting one or more suspected cases; 24 (60%) had a nonmeasles febrile rash illness rate of >2 cases per 100,000 popula->2 cases per 100,000 popula-population; and 16 (40%) met both targets. However, despite this progress, vaccination coverage reports remain imprecise, disease surveillance remains suboptimal, and outbreaks continue to occur, even in countries that reported implementation of all recommended components of the measles strategy. Available mathematical models likely overes-. Available mathematical models likely overestimate the disease burden and underreporting of measles cases is common, even with high-performing surveillance systems; therefore, caution is recommended when drawing comparisons between reported incidence of measles and estimates of measles deaths generated from models.

# Monitoring Measles Incidence
SIAs are recommended to provide a second opportunity for immunization and increase the likelihood of vaccinating hard-to-reach children. SIA coverage usually is estimated by an administrative method relying on the reported number of vaccine doses administered and available target population denominator data, both of which often are imprecise. For example, during 2001-2008, several countries reported vac-, several countries reported vaccinating >100% of children targets in SIAs. Improved methods for determining the actual target population size for SIAs are needed; reported coverage also should be routinely validated by independent surveys. In addition, detailed field investigations of outbreaks should be undertaken to identify post-SIA risk factors for measles, and help refine vaccination strategies.
The findings in this report are subject to at least two limitations. First, a change in measles surveillance methods might result in underestimates or overestimates of the disease burden over time. For example, in 1999, AFR countries routinely    (6). Second, although the case definition for suspected measles remained the same, the change in measles reporting practices might have led to either underreporting, because of the additional resources needed to complete individual case investigations and collect blood samples, or overreporting because of overall efforts to strengthen measles surveillance.
In light of progress made toward reducing measles deaths, a more advanced goal was proposed recently for the region with several recommendations to improve vaccination coverage and surveillance performance. The AFR measles technical advisory group met in May 2008 and recommended that AFR countries aim to meet the following targets by 2012: 1) reducing estimated measles deaths by 98%, compared with 2000 estimates; 2) reducing measles incidence to 80% in all districts; 4) achieving >95% SIA coverage in all districts; and 5) attaining two primary measles surveillance performance indicator targets (a nonmeasles febrile rash illness rate of >2 cases per 100,000 population per year and one or more suspected measles case investigated with blood specimen in >80% of districts per year); and 6) routine reporting from all districts (10). The group also recommended that AFR countries consider introduction of MCV2 in the routine vaccination schedule if MCV1 coverage of >80% has been achieved and maintained for 3 consecutive years and at least one of the two primary measles surveillance indicator targets has been achieved and maintained for at least 2 years. For countries adopting a 2-dose routine measles vaccination schedule, continued follow-up SIAs were recommended for all new birth cohorts every 3-5 years until national MCV2 coverage of 90% is sustained for at least 2 years (10).

# Updated Recommendation from the Advisory Committee on Immunization Practices (ACIP) for Revaccination of Persons at Prolonged Increased Risk for Meningococcal Disease
The Advisory Committee on Immunization Practices (ACIP) recommends quadrivalent meningococcal conjugate vaccine, (MCV4) (Menactra, Sanofi Pasteur, Swiftwater, Pennsylvania) for all persons aged 11-18 years and for persons aged 2-55 years at increased risk for meningococcal disease (1-3). MCV4 is licensed as a single dose. Because of the high risk for meningococcal disease among certain groups and limited data on duration of protection, at its June 2009 meeting ACIP recommended that persons previously vaccinated with either MCV4 or MPSV4 (Menomune, Sanofi Pasteur) who are at prolonged increased risk for meningococcal disease should be revaccinated with MCV4. Persons who previously were vaccinated at age 7 years and are at prolonged increased risk should be revaccinated 5 years after their previous meningococcal vaccine, and persons who previously were vaccinated at ages 2-6 years and are at prolonged increased risk should be revaccinated 3 years after their previous meningococcal vaccine. Persons at prolonged increased risk for meningococcal disease include 1) persons with increased susceptibility such as persistent complement component deficiencies (e.g., C3, properdin, Factor D, and late complement component deficiencies), 2) persons with anatomic or functional asplenia, and 3) persons who have prolonged exposure (e.g., microbiologists routinely working with Neisseria meningitidis, or travelers to or residents of countries where meningococcal disease is hyperendemic or epidemic). This report provides the rationale for the new recommendation and updates and replaces previous recommendations for revaccination with MCV4.
ACIP's Meningococcal Vaccine Work Group reviewed data on the risk for meningococcal disease, antibody titer decline, and the safety and immunogenicity of revaccination with MCV4 at 3 years and 5 years after the first dose of MCV4 or MPSV4 (2,3). Persons with prolonged increased risk for meningococcal disease have increased susceptibility to the disease or ongoing increased risk for exposure to N. meningitidis, higher levels of serum bactericidal antibody (SBA) against N. meningitidis can provide these groups increased protection against disease. SBA is a measure of the ability of sera to kill a strain of N. meningitidis in the presence of complement. In clinical trials, a baby rabbit SBA titer of 1:128 was used as a conservative correlate of protection (1). Small subsets of subjects from the MCV4 prelicensure clinical trial were revaccinated 3 years (n = 76) and 5 years (n = 134) after receiving MCV4. Of 71 persons aged 11-18 years at primary vaccination who had been vaccinated with MCV4 3 years previously, 75% and 86% had SBA titers greater than 1:128 for serogroups C and Y, respectively, before revaccination. Of 108 persons aged 2-10 years at primary vaccination who had been vaccinated with MCV4 5 years previously, 55% and 94% had SBA titers greater than 1:128 for serogroups C and Y, respectively, before revaccination. All persons revaccinated with MCV4 in these studies achieved SBA titers greater than 1:128 for serogroups C and Y. Approximately 50%-70% of persons in both the previously vaccinated (n = 210) and vaccine naive groups (n = 323) reported mild to moderate local and systemic adverse events after revaccination (or initial vaccination) with MCV4. However, no serious adverse events were reported in either group (Sanofi Pasteur, unpublished data, 2009).
On the basis of these data, expert opinion of the workgroup members, and feedback from partner organizations, the workgroup proposed that persons at prolonged increased risk for meningococcal disease be revaccinated with MCV4. ACIP approved this proposal at its June 24, 2009, meeting. Persons who previously were vaccinated at age 7 years and are at prolonged increased risk should be revaccinated 5 years after their previous meningococcal vaccine. Persons who previously were vaccinated at ages 2-6 years and are at prolonged increased risk should be revaccinated 3 years after their previous meningococcal vaccine. Persons who remain in one of these increased risk groups indefinitely should continue to be revaccinated at 5-year intervals.
Although the duration of protection from MCV4 is unknown, most entering college students will have received MCV4 within the preceding 4 years. Because of the limited period of increased risk, ACIP currently does not recommend that college freshmen living in dormitories who were previously vaccinated with MCV4 be revaccinated. However, college freshmen living in dormitories who were vaccinated with MPSV4 5 years previously are recommended to be vaccinated with MCV4. Information regarding MCV4 and other recommendations for persons aged 2-55 years (2,3), including a routine recommendation for vaccination with MCV4 in persons aged 11-18 years (4), has been published previously.

# Announcement
World Heart Day -September 27, 2009
Each year, approximately 17 million persons die from cardiovascular disease, mainly heart disease and stroke, making it the world's leading cause of death (1). Controlling certain risk factors, such as high blood pressure, high cholesterol, diabetes, obesity, tobacco use, and physical inactivity, can help prevent heart disease and stroke.
In 2000, the World Heart Federation, a nongovernmental organization based in Geneva, Switzerland, created the annual World Heart Day campaign to increase public awareness of the threat of heart disease and stroke. The theme of the 2009 World Heart Day is "Work with Heart -A Workplace That Encourages Healthy Habits Can Reduce Heart Disease and Stroke." Promoting physical activity and healthful eating and discouraging tobacco use around the workplace are simple ways to foster health in the workplace. Activities organized by members and partners of the World Heart Federation will include public talks, concerts, and sporting events. The national member organizations in the United States are the American College of Cardiology and the American Heart Association.
CDC funds heart disease and stroke prevention programs in 41 states and the District of Columbia. Additional information about these programs is available at / state_program/index.htm. Information about World Heart Day and the World Heart Federation is available at . world-heart-federation.org/what-we-do/world-heart-day.

# Announcement

# NHANES 50th Anniversary and Conference
The 50th anniversary of the National Health and Nutrition Examination Survey (NHANES) will be celebrated on September 29, 2009, at a conference at the National Center for Health Statistics in Hyattsville, Maryland. Collaborating agencies, data users, and program and field staff members will share their perspectives on the survey.

# NHANES began in 1959 as the National Health Examination
Survey. NHANES data come from household interviews and standardized examinations and laboratory testing of a sample of the nation's civilian, noninstitutionalized population. NHANES has expanded since the survey's inception to include a nutritional component now conducted in collaboration with the U.S. Department of Agriculture and measures of environmental exposure with the National Center for Environmental Health.
NHANES has long been a primary source of data on the nation's health. NHANES findings were used to set the goals and track the progress in reducing cholesterol levels, the prevalence of high blood pressure, and the risks of blood lead exposure in the United States. NHANES documented the rise in obesity and diabetes and produced the first populationbased estimates of human immunodeficiency virus infection and osteoporosis. NHANES data also are used for the growth charts by which pediatricians and parents check children's growth and development.
A hallmark of NHANES is its partnerships with other CDC programs, the National Institutes of Health, other U.S. Department of Health and Human Services programs, and other government agencies to collect data needed for public health policies and practice. Additional information about the NHANES 50th anniversary is available at / nchs/nhanes/nhanes50th.htm. The course includes a review of the fundamentals of descriptive epidemiology and biostatistics, measures of association, normal and binomial distributions, confounding, statistical tests, stratification, logistic regression models, and computer programs as used in epidemiology.

# Announcement

# Epidemiology in Action
The prerequisite is an introductory course in epidemiology, such as Epidemiology in Action or the International Course in Applied Epidemiology. Tuition will be charged. The application deadline is December 1, 2009, or until all slots have been filled.  1971-1974, 1976-1980, 1988-1994, 1999-2000, 2001-2002, 2003-2004, 2005-2006 1971-1974, 1976-1980, 1988-1994, 1999-2000, 2001-2002, 2003-2004, 2005-2006 Survey period Average total cholesterol (mg/dL) 1959-1962 1971-1974 1976-1980 1988-1994 Men   - Incidence data for reporting year 2009 is provisional, whereas data for 2004 through 2008 are finalized.  Calculated by summing the incidence counts for the current week, the 2 weeks preceding the current week, and the 2 weeks following the current week, for a total of 5 preceding years. The total sum of incident cases is then divided by 25 weeks. Additional information is available at .  Not reportable in all states. Data from states where the condition is not reportable are excluded from this