An acute gastroenteritis outbreak caused by GII.P16-GII.2 norovirus associated with airborne transmission via the air conditioning unit in a kindergarten in Lianyungang, China.

Noroviruses are a common cause of acute gastroenteritis outbreaks in institutions including schools and kindergartens around the world. An outbreak caused by GII.P16-GII.2 norovirus in a kindergarten in Lianyungang, Jiangsu Province, China is reported here. An epidemiological investigation was conducted, and pathogen detection was performed. The descriptive analysis indicated that this outbreak in middle class 1 had a point source. Twenty cases of acute gastroenteritis occurred in this class within a period of 8.5h; the attack rate was 52.6% (20/38). Airborne transmission via the air conditioning unit in a confined restroom could have played a critical role in this outbreak. Sequence analysis of GII-positive samples confirmed that the norovirus GII.P16-GII.2 variant was the etiological agent of this outbreak.

A community-based sero-epidemiological study of hepatitis B infection in Lianyungang, China, 2010

Introduction:The 2010 targets of the China Hepatitis B Prevention Programme were a prevalence of hepatitis B surface antigen (HBsAg) less than 1.0% for children less than five years old and less than 6.0% for the total population. This survey assessed the prevalence of Hepatitis B infection in Lianyungang, Jiangsu province, China in 2009–2010.Methods:Multistage sampling was used with 2372 subjects among 17 selected villages. Blood specimen collection and testing by enzyme-linked immunosorbnet assay (ELISA) were completed using the following markers for hepatitis infection: HBsAg and antibody to HBsAg (anti-HBs); hepatitis B e antigen (HBeAg) and antibody to HBeAg (anti-HBe); and hepatitis B core antibody (total anti-HBc). The data were analysed with Epi Info, version 3.3.2.Results:The prevalence of HBsAg was 2.4% (95% Confidence Interval [CI]: 1.8–3.0; Adjusted Prevalence [AP] 2.9%); anti-HBs prevalence was 51.1% (95% CI: 49.1–53.1; AP 49.2%) and total anti-HBc prevalence was 41.7% (95% CI: 39.8–43.7; AP 45.5%). The prevalence of HBsAg and total anti-HBc positivity increased from young to older age groups, yet the prevalence of anti-HBs positivity decreased from young to older age groups (PP= 0.108 and 0.089), but females had a higher prevalence than males for total anti-HBc positivity (P< 0.001). Discussion: This survey showed that in 2010 the prevalence of HBsAg among children aged less than five years was lower than the national target of 1.0% and that the prevalence of HBsAg for the total population was lower than the national target of 6.0%.

[Application of 1D wavelet analysis in detecting species of harmful algae blooms with absorption spectra of phytoplankton].

In the present study, the feasibility of using wavelet analysis to extract the eigen spectra from the absorption spectra of phytoplankton for species detection was investigated. Thirteen absorption spectra taken from single species cultures, representing four divisions (Dinophyta, Bacillariophyta, Haptophyta, and Chlorophyta), six genus (Gymnodinium, Prorocentrum, Skeletonema, Guinardia, Phaeocystis, and Prasinophyte) and seven species (Karenia mikimotoi, Karenia brevis, Prorocentrum minimum, Skeletonema costatuma, Guinardia delicatula, Phaeocystis globosa, and Pyramimonas parkeae), were used. First, the 1D wavelet analysis with five levels was applied to the thirteen absorption spectra, so each spectrum was decomposed with 5 levels. The 5th level component of low frequency corresponds to the background without information for species detection, and 1st and 2nd level component of high frequency is the random noise. The other levels (3rd to 5th) of high frequency are the useful information, and the sum of levels (3rd to 5th) of high frequency was retained as the eigen spectra for species detection. Second, the clustering analysis was used to the eigen spectra for examining the performance of the wavelet analysis in extracting species information. The clustering results were compared with the known species class information, and the results show that the 13 absorption spectra are correctly classified at the level of division, genus and species. This means that the wavelet analysis has good performance in extracting the eigen spectra for species detection. However, the above results were obtained with only limited species, and the more species data are required to identify the extensive validity of the conclusion.