A community-based cross-sectional immunisation survey in parents of primary school students.

Immunisation is a very important aspect of child health. Invasive pneumococcal and influenza diseases have been major vaccine-available communicable diseases. We surveyed demographics and attitudes of parents of primary school students who received pneumococcal conjugate vaccination (PCV) and compared them with those who did not receive pneumococcal vaccination. The survey was carried out in randomly selected primary schools in Hong Kong. Questionnaires were sent to nine primary schools between June and September 2014. Parents of 3,485 children were surveyed, and 3,479 (1,452 PCV immunised, 2,027 un-immunised) valid questionnaires were obtained. Demographic data were generally different between the two groups. PCV-immunised children were more likely to be female (57.0 vs. 52.2%, P=0.005), born in Hong Kong (94.2 vs. 92.3%, P=0.031), have a parent with tertiary education (49.2 vs. 31.8, P<0.0005), from the higher-income group (P=0.005), have suffered upper respiratory infections, pneumonia, otitis media or sinusitis (P=0.019), and have doctor visits in preceding 12 months (P=0.009). They were more likely to have received additional immunisations outside the Hong Kong Childhood Immunization Programme (64.0 vs. 30.6%, P<0.0005) at private practitioner clinics (91.1 vs. 83.5%, P<0.0005). Un-immunised children were more likely to live with senior relatives who had not received PCV. Their parents were less likely to be aware of public education programme on PCV and influenza immunisation, and children were less likely to have received influenza vaccination. The major reasons for PCV immunisations were parent awareness that pneumococcal disease could be severe and vaccines were efficacious in prevention. The major reasons for children not being immunised with PCV were concerns about vaccine side effects, cost, vaccine not efficacious or no recommendation by family doctor or government. In conclusion, PCV unimmunized children were prevalent during the study period. Reportedly, they were generally less likely to have received influenza and other childhood vaccines, and more likely to live with senior relatives who had not received PCV and influenza. These observations provide important demographic data for public health policy in childhood immunisation programme.

Pneumonia in childhood and impaired lung function in adults: a longitudinal study.

BACKGROUND: Diminished lung function and increased prevalence of asthma have been reported in children with a history of early lower respiratory illnesses (LRIs), including pneumonia. Whether these associations persist up to adulthood has not been established. METHODS: As part of the prospective Tucson Children's Respiratory Study, LRIs during the first 3 years of life were ascertained by pediatricians. Spirometry was performed at ages 11, 16, 22, and 26 years. The occurrence of asthma/wheeze during the previous year was ascertained at ages 11, 13, 16, 18, 22, 24, 26, and 29 years. Longitudinal random effects models and generalized estimating equations were used to assess the relation of LRIs to lung function and asthma. RESULTS: Compared with participants without early-life LRIs, those with pneumonia had the most severe subsequent lung function impairment, with mean ± SE deficits of -3.9% ± 0.9% (P < .001) and -2.5% ± 0.8% (P = .001) for pre- and post-bronchodilator FEV1:FVC ratio from age 11 to 26 years, respectively. Pneumonia was associated with increased risk for asthma (odds ratio [OR]: 1.95; 95% confidence interval [CI]: 1.11-3.44) and wheeze (OR: 1.94; 95% CI: 1.28-2.95) over the same age range. Early non-pneumonia LRIs were associated with mildly impaired pre-bronchodilator FEV1 (-62.8 ± 27.9 mL, P = .024) and FEV1:FVC ratio (-1.1 ± 0.5%, P = .018), and wheeze (OR: 1.37; 95% CI: 1.09-1.72). CONCLUSIONS: Early pneumonia is associated with asthma and impaired airway function, which is partially reversible with bronchodilators and persists into adulthood. Early pneumonia may be a major risk factor for adult chronic obstructive pulmonary disease.

Rotavirus incidence in hospitalised Hong Kong children: 1 July 1997 to 31 March 2011.

Sentinel laboratory surveillance from one hospital and passive discharge diagnosis (Clinical Management System, CMS) data from all public Hospital Authority (HA) hospitals were used to estimate disease burden and incidence of rotavirus in hospitalised Hong Kong children over 14 rotavirus seasons (1 July 1997 to 31 March 2011). A primary diagnosis of a gastroenteritis-related disorder was noted in 9.8% of children aged below 5 years, and a primary or secondary diagnosis in 11.8%. Any CMS diagnosis of rotavirus (ICD 008.61) was initially used to derive incidence estimates of rotavirus by age group. Rotavirus was recorded as any primary or any secondary diagnosis in 1.6% of children below 5 years of age. The unadjusted incidence rates per 100,000 person-years based on any CMS diagnosis of rotavirus were: 249 (0 to <1m); 612 (1 to <2m); 1066 (2 to <6m); 1383 (6 to <11m); 959 (1 to <2y); 406 (2 to <3y); 233 (3 to <4y); 124 (4 to <5y). Overall the rotavirus incidence was 1071 in children below 2 years and 542 in children below 5 years of age, with the incidence rates trending up during the time period (p=0.001). A similar but less marked upward trend (p=0.046) was noted for the incidence of all-cause gastroenteritis. Laboratory results from a single surveillance hospital (1 July 2000 to 31 March 2011) were then linked to these CMS codes to derive adjustment factors for possible over- and under-diagnosis of rotavirus based on CMS codes alone. This analysis suggested that a CMS diagnosis of rotavirus alone likely under-reported true incidence by a factor of between 1.59 and 2.02 in children below 5 years of age. Despite the availability of rotavirus vaccines in the private sector since 2006, no reduction in the incidence of hospitalisation for either rotavirus or all-cause gastroenteritis was noted in Hong Kong children below 5 years of age over 14 rotavirus seasons (1997-2011).