Impact of nationwide measles vaccination campaign among children aged 9 months to 14 years,Zimbabwe, 1998-2001

Zimbabwe (population 11,365,000) introduced nationwide one-dose measles vaccination in 1981. This strategy reached 70%-80% of infants <1 year of age over the next two decades; in 1998, a nationwide supplemental immunization activity (SIA) targeting all children aged 9 months to 14 years achieved 93% coverage. Surveillance data were examined to determine the impact of these strategies. During 1985-1997, there were 8529-49,812 measles cases annually. After the SIA, laboratory confirmation of the first 5 outbreak cases and all sporadic cases was required. In 1999 and 2000, 1343 (88%) of 1534 suspected cases had adequate specimens submitted and 28 (2%) were measles IgM positive. In 2001, of 529 suspected cases, 513 (97%) had adequate specimens and only 7 (1%) were measles IgM positive. These data suggest that indigenous measles transmission in Zimbabwe has been interrupted and that high prevalence of human immunodeficiency virus seropositivity does not hinder vaccination-induced measles control. High vaccination coverage obtained through the routine health care system supplemented by periodic follow-up SIAs will be required to maintain low transmission levels.     

Can WHO therapy failure criteria for non-severe pneumonia be improved in children aged 2-59 months?

SETTING: In the recent past, there have been reports of rising treatment failure rates for non-severe pneumonia. It is felt that World Health Organization (WHO) criteria for therapy failure are too sensitive and that many children are unnecessarily classified as failures. We studied alternative, less sensitive therapy failure criteria. METHODS: In this nested study we followed the clinical course of non-severe pneumonia in children aged 2-59 months using alternative therapy failure criteria. All children received amoxicillin and were followed up on days 3, 5 and 14 after enrollment. On day 3, children were labelled as therapy failure only if their condition had deteriorated. These failure rates were compared with those using WHO definitions. RESULTS: During the study period, 876 children with non-severe pneumonia were followed up until day 14. On day 3, using alternative therapy failure criteria, 31 (3.5%) children were labelled as therapy failure compared to 95 (10.8%) using current WHO criteria. The difference was statistically significant (P = 0.001). CONCLUSIONS: The alternative therapy failure criteria work reasonably well, without causing any higher risk to children with non-severe pneumonia. Antibiotics should be changed only in those children who show signs of deterioration on day 3. This would prevent unnecessary changes in antibiotic treatment in many children.     

Value of chest radiography in predicting treatment response in children aged 3-59 months with severe pneumonia

SETTING: International multicentric study at nine tertiary care centres. OBJECTIVE: The World Health Organization (WHO) currently does not recommend chest radiographs (CXRs) for routine management of pneumonia. We evaluated the use of CXR for the prediction of treatment failure in children with severe pneumonia. DESIGN: We used WHO vaccine trials radiographic assessment, clinical and nasopharyngeal microbiological data from 1121 3-59-month-old children recruited using the WHO definition of severe pneumonia in the Amoxicillin Penicillin Pneumonia International Study (APPIS). Using Poisson regression, we estimated the relative risk of developing clinical treatment failure and predictive preventive benefit of the CXR and examined the concordance of the CXR findings with the nasopharyngeal microbiological data. RESULTS: A CXR with 'significant pathology' (defined by the WHO algorithm as end-point consolidation, pleural fluid and other infiltrates) was associated with a high risk of treatment failure, especially in children who received penicillin as compared to oral amoxicillin. Significant pathology was also associated with nasopharyngeal isolation of penicillin-resistant Streptococcus pneumoniae. Children with a normal CXR had a reduced risk of clinical treatment failure. CONCLUSIONS: CXR with significant pathology independently and additively predicts clinical treatment failure. If CXR and the WHO tool are available, they can be used in the management of severe pneumonia.     

Impact of mass measles campaigns among children less than 5 years old in Uganda

In 1999-2001, a national measles control strategy was implemented in Uganda, including routine immunization and mass vaccination campaigns for children aged 6 months to 5 years. This study assesses the impact of the campaigns on measles morbidity and mortality. Measles cases reported from 1992 through 2001 were obtained from the Health Management Information System, and measles admissions and deaths were assessed in six sentinel hospitals. Measles incidence declined by 39%, measles admissions by 60%, and measles deaths by 63% in the year following the campaigns, with impact lasting 15 to 22 months. Overall, 64% of measles cases were among children <5 years of age, and 93% were among children 相似文献   

9月龄～6岁健康儿童麻疹和风疹抗体水平监测

目的 了解新疆阿克苏地区9月龄～6岁健康儿童麻疹和风疹抗体水平,及时发现免疫薄弱人群,采取针对性免疫措施.方法 采用分层随机抽样法,采集839名9月龄～6岁健康儿童血清标本,采用酶联免疫吸附试验(ELISA)检测麻疹和风疹IgG抗体.结果 839名儿童麻疹抗体阳性率为94.3％,抗体几何平均滴度(GMT)为1 541.2 mIU/ml;风疹抗体阳性率为92.1％,抗体几何平均滴度(GMT)为958.4 mIU/ml.不同免疫剂次和不同年龄组儿童麻疹、风疹抗体阳性率和GMT水平不同,差异有统计学意义(P＜0.05).结论 阿克苏地区9月龄～6岁健康儿童麻疹、风疹IgG抗体水平总体较高,但仍存在薄弱环节,1岁以下儿童是麻疹和风疹的高危人群,应加强此部分人群的针对性免疫策略.     

Failure of targeted urban supplemental measles vaccination campaigns (1997-1999) to prevent measles epidemics in Mozambique (1998-2001)

This study assessed the effect of urban supplemental measles vaccination campaigns (1997-1999) in Mozambique that targeted children aged 9-59 months. Reported measles cases were analyzed to the end of 2001 to determine campaign impact. Hospital inpatient data were collected in the national capital and in three provincial capitals where epidemics occurred the year after the campaigns. Measles epidemics followed campaigns in the capital city, in 4 of 9 provincial capitals, and in 39 of 126 districts. Reasons for limited campaign impact included a low proportion of urban dwellers, the geographic location of some provincial capitals, the limited target age group, and low routine and campaign coverage. Routine immunization and disease surveillance should be strengthened and campaigns must achieve >90% coverage and target wider age groups and geographic areas in order to reach a high proportion of persons susceptible to measles.     

Trial of Edmonston-Zagreb measles vaccine in infants aged under nine months.

Due to the recent finding that most infants in developing countries have lost maternal antibody for measles before nine months of age, immunization of infants younger than the recommended age of nine months would help reducing the incidence of measles in these endemic areas. We conducted a trial of Edmonston-Zagreb measles vaccine which is the strain that may be more immunogenic in young infants than the widely used Schwarz strain. Forty-five infants with mean age of 25 weeks received a dose of Edmonston-Zagreb vaccine. Antibody levels were measured, using plaque neutralization test, before and about 3 months after vaccination at which mean age was 38 weeks. The seroconversion rate was 89%. Only two infants (4.4%) had immunity before vaccination. Fifteen infants (33.33%) reported some adverse reactions including fever (13.33%), rhinorrhea (8.89%), rash (4.44%) and local reactions (22.22%). All of the reactions resolved spontaneously. We conclude that Edmonston-Zagreb measles vaccine is efficacious and safe in infants aged under nine months.     

Impact of mass vaccination campaigns on measles transmission during an outbreak in Guinea, 2017

ObjectiveTo estimate the time-dependent measles effective reproduction number (R_t) as an indicator of the impact of three outbreak response vaccination (ORV) campaigns on measles transmission during a nationwide outbreak in Guinea.MethodsR_t represents the average number of secondary cases generated by a single primary case in a partially immune population during a given time period. Measles R_t was estimated using daily incidence data for 3952 outbreak-associated measles cases in Guinea in 2017 for the time periods prior to, between, and following each of three ORV campaigns using a simple and extensible mathematical model.ResultsR_t was estimated to be above the threshold value of 1 during the initial growth period of the outbreak until the first ORV campaign began on March 13 (R_t = 1.60, 95% CI: 1.55–1.67). It subsequently dropped below 1 and remained <1 through the end of the year (range: 0.71–0.91), although low levels of transmission persisted.ConclusionsReduction in R_t coincided with implementation of the ORV campaigns, indicating success of the campaigns at maintaining measles transmission intensity below epidemic growth levels. However, persistent measles transmission remains an issue in Guinea due to insufficient levels of herd immunity. Estimation of R_t should be further leveraged to help decision makers and field staff understand outbreak progress and the timing and type of vaccination efforts needed to halt transmission.     

Evaluation of the immune response to a 2-dose measles vaccination schedule administered at 6 and 9 months of age to HIV-infected and HIV-uninfected children in Malawi

BACKGROUND: The World Health Organization recommends that infants at high risk for developing measles before 9 months of age, including human immunodeficiency virus (HIV)-infected infants, receive measles vaccination (MV) at 6 and 9 months of age. METHODS: Children born to HIV-infected mothers received MV at 6 and 9 months, and children of HIV-uninfected mothers were randomized to receive MV at 6 and 9 months, MV at 9 months, or routine MV without follow-up. Blood samples were obtained before and 3 months after each MV. Data were collected on adverse events for 21 days after each MV, at all clinic visits, on any hospitalization, and for subjects who died. HIV-infection status was determined by antibody assays and polymerase chain reaction; the presence of measles IgG was determined by EIA. RESULTS: Twenty-two hundred mother-infant pairs were enrolled. After the first and second doses of measles vaccine, respectively, the percentages of children who were measles seropositive were 59% (36 of 61) and 64% (29 of 45) among HIV-infected children, 68% (152 of 223) and 94% (189 of 202) among HIV-exposed but uninfected children, and 62% (288 of 467) and 92% (385 of 417) among HIV-unexposed children. Of 521 HIV-unexposed children vaccinated only at 9 months, 398 (76%) were measles seropositive at 12 months. No serious vaccine-related adverse events were identified. CONCLUSIONS: An early, 2-dose MV schedule was immunogenic, but a higher proportion of HIV-infected children remained susceptible to measles, compared with HIV-uninfected children (whether HIV exposed or HIV unexposed).     

Comparison of clinical outcome with oral and inhaled bronchodilators in the management of wheezy children aged 1-59 months in the community: a randomised trial in Pakistan.

BACKGROUND: Wheeze is a significant problem in children. There is a gradual trend of switching from oral to inhaled bronchodilator therapy. No randomised trials have been carried out in the community to compare the clinical outcome of two modes of therapy. If outcome with oral and inhaled bronchodilators is the same in young wheezers in developing countries, it will be easier to manage them. METHODS: In a randomised multicentre trial, wheezy children aged 1-59 months with fast breathing and/or lower chest indrawing received oral or inhaled salbutamol at home after responding to up to three cycles of inhaled bronchodilators. They were re-assessed on days 3 and 5 for clinical outcome. RESULTS: From May 2001 to August 2002, 780 children were enrolled; 390 each were randomised to oral and inhaled salbutamol. On day 5, 324 (83.1%) children in the oral and 328 (84.1%) in the inhaled group were completely well. There were no differences in clinical outcome of both modes of therapy. CONCLUSIONS: The clinical outcome of children aged 1-59 months with wheeze is similar when treated with oral or inhaled salbutamol. Acute respiratory infection control programmes in developing countries should continue to use oral bronchodilators for the management of wheeze to save both time and money.     

Adjustment of fat-free mass and fat mass for height in children aged 8 y

OBJECTIVE: To explore the relationships between height and (a) fat-free mass (FFM) and (b) fat mass (FM) in children in order to determine the optimum means of adjusting body composition for height. DESIGN: Cross-sectional study. SUBJECTS: Sixty-nine children aged 8 y. MEASUREMENTS AND METHODS: Weight and height (HT) were measured, and total body water by deuterium dilution for estimation of fat-free mass and fat mass. The indices FFM/HT(2) and FM/HT(2) were calculated, as were the indices FFM/HT(p) and FM/HT(p) where P was selected in order to eliminate the correlation of these indices with height. RESULTS: FFM was optimally adjusted for height by calculating FFM/HT(2). FM was optimally adjusted by calculating FM/HT(6). However, height accounted for <8% of the variation in FM/HT(2), indicating that the bias of this simpler index is small. CONCLUSIONS: Different adjustments of FFM and FM for height are possible, depending on the study design. The indices FFM/HT(2) and FM/HT(2) are appropriate for many purposes, and have the advantage of expressing both aspects of body composition in common units. However, in some scenarios a more sophisticated approach is required for evaluating body fatness.     

Developmental coordination disorder and overweight and obesity in children aged 9-14 y

Developmental coordination disorder (DCD) is a significant problem that affects between 5 and 9% of all children. Since children with DCD are less likely than their non-DCD peers to participate in physical activities, they may be at greater risk for overweight and obesity. In this report, we examine the relationship between DCD and overweight and obesity in a sample of 578 children aged 9-14 y. We also examine whether the relationship between DCD and overweight/obesity is the same for boys and girls, taking into account sex and age-appropriate differences in percentage body fat and body mass index (BMI) criteria. Our results show that for boys, DCD may be a risk factor for overweight/obesity in childhood and early adolescence. For girls, there is no difference in the prevalence of overweight/obesity between children with and without the disorder.