ABSTRACT
Objective We conducted an epidemiologic investigation to determine the source of infection on an avian influenza (H5N1) case who returned from Guangzhou,in Hong Kong.Methods Data related to epidemiologic investigation,medical observation on close contacts,Syndromic Surveillance on poultry salesmen,emergency monitoring,detection of the samples,source tracing on potential Avian influenza virus (H5,H7,H9) infected people,situation on environment pollution by avian influenza virus in the markets etc.were gathered.The determination of infection source was through comparing the different genes between the case and positive environmental samples.Results The infected case witnessed the procedure of how a live duck was killed,in market A in Guangzhou during May 17th to 19th.The case was diagnosed as respiratory tract infection in 2 Third-grade-Class A hospitals in Guangzhou on May 23th and 24th.The diagnosis was made as Avian influenza cases on May 26th after going back to Hong Kong.23 close contacts and 34 markets poultry salesmen did not show any ILI related symptoms.However,2 poultry salesmen from the markets nearby the place where the Avian influenza case stayed,were detected having positive H9 avian influenza antibody,with the H9 positive rate as 6.06％ (2/33).Among the environmental samples in the 2 markets nearby home of the patient,chopping block was found to have carried H5,with positive rate as 9.8％(5/51) while poultry cage was found to carry H9,with the positive rate as 2.0％(1/51).A H5 positive sample was found with clade 2.3.2.1,same to the case,from a chopping block at the market B where the sources of poultry was the same as market A.Conclusion The source of infection seemed to come from the markets in Guangzhou,that calling for the strengthening of poultry market management,for avian influenza prevention.History related to contact of poultry should be gathered when a diagnosis of respiratory tract infection was made.Timely sampling and testing should be made to improve the sensitivity of diagnosis.
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Objective To understand the changes of hepatitis B infection rates,before and after the hepatitis B vaccine Was included into EPI.and to evaluate the effect of immunization which would lead to the development of a more appropriate hepatitis B control strategy.Methods Seroepidemiologic method,with multi-section random sampling method were chosen.14 sites from 8 counties were involved.2-4 ml of the vein blood was drawn from all the individuals engaged in the study including 3806 samples.HBsAg,anti-HBs.anti-Hbe of the samples were tested with ELISA.Results Standardized positive rates of HBsAg and HBsAb were found as 7.05%and 29.77%respectively with the overall infection rate of HBV as 40.30%.The hepatitis B vaccine coverage of the children under 15 years was 70.73%and the positive rates for both HBsAg and anti-HBS were 2.62%and 56.68%.respectively.The coverage of hepatitis B vaccine among children under 3 years was 83.44%and the positive rates of both HBsAg and anti-HBs were 1.47%and 67.69%respectively.hepatitis B vaccine coverage of children under 3 years was 85.77%.with positive rates of HBsAg and anti-HBs as 1.78%and 75.44%respectively.Conclusion Results from our study revealed that since the introduction of hepatitis B vaccination,the prevalence rates of HBsAg and HBV infeetion had an obvious decline,especially in children aged under 15 years of old,suggesting that some changes had occurred in the epidemic characteristics ofhepatitis B in Sichuan.
ABSTRACT
<p><b>OBJECTIVE</b>To assess the feasibility of the 10 microg recombination yeast hepatitis B vaccine in the expanded applicable population group aged 5 - 18.</p><p><b>METHODS</b>People with both HBsAg and anti-HBs negative were selected to take two-stage clinical experiment and the safety and immunogenicity were observed. Safety observation was conducted in 925 subjects, while 568 for immunogenicity. The observation group (aged 5 - 18) included 493 subjects, and (age > 18) 75 enrolled in control group. For the observation group, there were three sub-groups including a child group (141, aged 5 - 6), early youth group (177, aged 12 - 13), and youth group (175, aged 16 - 18). Both groups were administered with 10 microg recombination yeast hepatitis B vaccines with 3 doses at 0 month, 1st month, 6th month. To assess the immunogenicity, the vaccination reactions were observed during the following 4 weeks in order to assess the vaccine safety. The blood samples were taken during 4 - 6 weeks after fully vaccinated, and then anti-HBs were tested with RIA and analyzed by comparing the positive rate of anti-HBs, the geometric mean titer (GMT) and the protective rate between the two groups.</p><p><b>RESULTS</b>Both observation and control group didn't show any general reactions, adverse events following immunization (AEFI) or coincidental cases when observed at 0.5 h, 6 h, 24 h, 48 h, 72 h, 1 week, 2 weeks, 3 weeks, 4 weeks after being vaccinated. The result of serum test showed, the positive rates of child group, early youth group, youth group and control group were respectively 100.00% (141/141), 97.18% (172/177), 98.29% (172/175) and 89.33% (67/75); the GMTs of anti-HBs were respectively 440.28, 875.38, 467.80, 131.06 U/L; the protective rates were respectively 100.00% (141/141), 97.18% (172/177), 97.14% (170/175) and 86.67% (65/75). The positive rate, GMT and protective rate of the experimental group were all higher than that of control group (chi(2)(positive rate) = 12.77, 5.12, 7.99; t(GMT) = 3.89, 4.13, 5.91; chi(2)(protective rate) = 16.81, 8.60, 8.44; P < 0.05).</p><p><b>CONCLUSION</b>This vaccine could be expanded to 5 - 18 year-old population with safety and effectiveness, the positive rate and protective rate of anti-HBs were both higher than that of control group.</p>
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Male , Hepatitis B Antibodies , Blood , Allergy and Immunology , Hepatitis B Surface Antigens , Blood , Allergy and Immunology , Hepatitis B Vaccines , Allergy and Immunology , Vaccines, Synthetic , Allergy and ImmunologyABSTRACT
<p><b>OBJECTIVE</b>To investigate the seroprevalence of HEV infection and genotype.</p><p><b>METHODS</b>ELISA were used for detecting anti-HEV IgG of the serum samples, the nested reverse transcriptase PCR (RT-nPCR) was used for detecting HEV RNA in patient serum and swine bile samples. All samples were collected in 2005-2007 in some districts in Sichuan province. The primers used for genotyping were the ORF2 region of HEV genome.</p><p><b>RESULTS</b>The anti-HEV IgG was detected positive in childrens 6.10% (41/672), adults 42.26% (280/ 661), swines 88.89% (32/36), chickens negative (0/59). 1 case of 15 serum samples of anti-HEV IgM positive and 3 of 54 swine bile samples were positive for HEV RNA by RT-PCR.Sequence analysis of 4 isolates has 92.1% to 98.6% nucleotide sequence homology. These isolates from human and swine were identified closely related to Ch-T21 strain 90.1%-96.9% sequence homology, which belonged to HEV genotype 4B.</p><p><b>CONCLUSIONS</b>The swine were the risk factors in the spread of hepatitis E virus.</p>