The application of the cholera vaccine is one of the cholera prevention and control strategies. Cholera vaccines stimulate mucosal immune to play the role of antibacteria and antitoxin. When the cholera toxin B subunit is added in the cholera vaccine, it could also defend against some diarrhea associated pathogens by cross-protection. Oral inactivated cholera vaccines are commercially available now. The oral live vaccine candidates are under development. The development of cholera vaccine is not only on the technical aspect, based on the situations of epidemic areas and population, cost, storage and transportation condition should also be considered. Though the argument on the use of cholera vaccine in epidemic areas and population in high risk existed previously, its vaccination has reached agreement now based on the clinical trials and evaluations during epidemic period.
Administration, Oral ; Cholera ; Cholera Toxin ; Cholera Vaccines ; Cross Protection ; Diarrhea ; Humans ; Vaccination ; Vaccines, Attenuated ; Vaccines, Inactivated

OBJECTIVETo evaluate immunogenicity after primary vaccination by different sequential program of inactivated poliovirus vaccine (IPV) and oral poliovirus vaccine (OPV).

METHODSChildren of 2 months old (60-89 days) selected in Beijing were assigned to 4 groups, 1 dose IPV plus 2 doses OPV (I-O-O, 122 children), 2 doses IPV plus 1 dose OPV(I-I-O, 103 children), 3 doses IPV (I-I-I, 114 children), and 3 doses OPV (O-O-O, 106 children), and were vaccinated at the age of 2, 3, 4 months. Polio neutralizing antibody titers against poliovirus types 1, 2, and 3 were tested and protective rates were calculated before the 1st dose, after the last dose, and after the 1st and 2nd dose of IPV.

RESULTSAfter the primary immunization, geometric mean titers (GMT) of polio neutralizing antibody titers against poliovirus types 1, 2, and 3 were 788.32, 738.42 and 631.17 in O-O-O group, 212.02, 262.30 and 537.52 in I-I-I group, 940.35, 929.72 and 940.35 in I-O-O group and 901.09, 1102.68 and 1110.12 in I-I-O group (F values were 47.71, 53.84, and 9.81 respectively, all P values<0.01). The protective rate of three types among each group was 98.1% (104/106)-100.0% and the difference was not statistically significant (P>0.05). After the 1(st) dose of IPV, the GMT were 18.88, 37.77, 24.64 and the protective rate was 82.6% (122/138)-96.4% (133/138); after the 2nd dose of IPV, GMT were 177.03, 168.25, 321.86 and the protective rate was 99.1% (108/109)-100.0% (109/109) in antibody types 1, 2 and 3, respectively.

CONCLUSIONGMT of polio neutralizing antibody titers against poliovirus is higher after vaccination by sequential program of IPV and OPV than that by IPV or OPV 3-doses program. High level of protective rate after 2 doses of IPV in I-I-O group may lead to better protection from vaccine associated paralytic poliomyelitis (VAPP). Sequential program of IPV and OPV can be used to maintain high level of herd immunity and to prevent VAPP, and the I-I-O sequential program should be the first choice.

Humans ; Immunization Schedule ; Infant ; Poliovirus Vaccine, Inactivated ; administration & dosage ; immunology ; Poliovirus Vaccine, Oral ; administration & dosage ; immunology ; Vaccines, Attenuated ; immunology

OBJECTIVETo evaluate safety of different sequential immunization schedules of inactivated poliovirus vaccine (IPV) and oral poliovirus vaccine (OPV) primary vaccination.

METHODSInfants of 2 months old (60-89 days) selected in Beijing, were assigned to four groups, 1 dose IPV plus 2 doses OPV (I-O-O), 2 doses IPV plus 1 dose OPV(I-I-O), 3 doses IPV (I-I-I), and 3 doses OPV (O-O-O), and were vaccinated at the age of 2, 3, 4 months, from 2009 to 2011. The frequencies of systemic as well as local injection site reactions after every dose were recorded and calculated. A total of 553 infants were enrolled in the study and 89 infants were quit, 1492 diseases were observed.

RESULTSThe incidence of adverse events in I-O-O, I-I-O, I-I-I, O-O-O were 22.9% (94/410), 18.4% (60/327), 22.0% (78/354) and 17.7% (71/401) with no statistical differences (χ(2) = 4.84, P = 0.184). Dose 1 (22.7% (32/141)-35.3% (54/153) ) was more frequently than dose 2 and dose 3. No serious adverse events (SAE) were reported during the study. The incidence of systemic adverse reactions in I-O-O, I-I-O, I-I-I, O-O-O were 21.5% (88/410), 17.7% (58/327) , 20.1% (71/354) and 17.7% (71/401) with no statistical differences (χ(2) = 2.53, P = 0.472). Abnormal crying were the most frequency reactions (7.2% (29/401)-11.3% (37/327) ) in 4 groups. Rarely severe reactions were observed of abnormal crying, somnolence, irritability and mild or medium reactions occurred in other symptoms. Local adverse reactions such as injection site pain, scleroma and swelling were reported by 2.2% (5/229)-5.6% (22/393) ,0-0.9% (2/229) and 0-1.0% (4/393) in I-O-O,I-I-O and I-I-I, and most reactions were mild.

CONCLUSIONThree IPV immunization and IPV/OPV sequential immunization as well as three OPV immunization demonstrated safe.

Humans ; Immunization Schedule ; Infant ; Poliovirus Vaccine, Inactivated ; administration & dosage ; adverse effects ; Vaccines, Attenuated ; administration & dosage ; adverse effects

OBJECTIVEUsing the advantages of Japanese encephalitis live attenuated and inactivated vaccine, to reduce the rate of immunization reaction and to increase the effect, we conducted a study on the strategy of immunization in Japanese encephalitis using live attenuated vaccine combined with inactivated vaccine.

METHODSObserving the safety and immune effects of different groups.

RESULTSData on side effect showed that the rate of moderate and severe systematic reactions of the group who were inoculated with combined vaccine was 0.73%, with local reaction 1.46% while the combined rate of moderate and severe systematic reaction of the group who were inoculated with inactivated vaccine was 2.8%. Under the detection of serum neutralizing antibody, the GMT rose from 1:1.05 - 1:3.35 before vaccination to 1:47.34 - 1:101.30 after vaccination in the different groups. Neutralizing antibody was detected in 97.67% of the combined group. There was a significant difference by comparing neutralizing antibody seroconversion rate of the combined group with the inactivated group (chi(2) = 3.89, P < 0.05), but no significant difference with attenuated group (chi(2) = 0.74, P > 0.05).

CONCLUSIONResults showed that in children who previously had been immunized with two doses of inactivated vaccine, the booster administration of live attenuated vaccine was both effective and safe.

Antibodies, Viral ; blood ; Child, Preschool ; Encephalitis Virus, Japanese ; immunology ; Humans ; Immunization ; Japanese Encephalitis Vaccines ; administration & dosage ; adverse effects ; immunology ; Vaccines, Attenuated ; immunology ; Vaccines, Inactivated ; immunology

Salmonella enterica Gallinarum (SG) causes fowl typhoid (FT), a septicemic disease in avian species. We constructed deletion mutants lacking the stress sigma factor RpoS, the nitric oxide (NO)-detoxifying flavohemoglobin Hmp, and the SsrA/SsrB regulator to confirm the functions of these factors in SG. All gene products were fully functional in wild-type (WT) SG whereas mutants harboring single mutations or a combination of rpoS, hmp, and ssrAB mutations showed hypersusceptibility to H2O2, loss of NO metabolism, and absence of Salmonella pathogenicity island (SPI)-2 expression, respectively. A triple-deletion mutant, SGDelta3 (SGDeltarpoSDeltahmpDeltassrAB), was evaluated for attenuated virulence and protection efficacy in two-week-old Lohmann layer chickens. The SGDelta3 mutant did not cause any mortality after inoculation with either 1 x 10(6) or 1 x 10(8) colony-forming units (CFUs) of bacteria. Significantly lower numbers of salmonellae were recovered from the liver and spleen of chickens inoculated with the SGDelta3 mutant compared to chickens inoculated with WT SG. Vaccination with the SGDelta3 mutant conferred complete protection against challenge with virulent SG on the chickens comparable to the group vaccinated with a conventional vaccine strain, SG9R. Overall, these results indicate that SGDelta3 could be a promising candidate for a live Salmonella vaccine against FT.
Administration, Oral ; Animals ; Bacterial Proteins/*genetics/immunology ; *Chickens ; Female ; Poultry Diseases/*immunology/microbiology ; Salmonella Infections, Animal/*immunology/microbiology ; Salmonella Vaccines/administration & dosage/genetics/*immunology ; Salmonella enterica/immunology/*physiology ; Vaccines, Attenuated/administration & dosage/genetics/immunology ; Virulence

OBJECTIVETo observe the immunological effects of three doses of H2 strain live attenuated hepatitis A vaccine 8 years after the administration and to compare with that of one dose of the vaccine.

METHODSIn a country area, 110 children of 1 to 7 years old susceptible to HAV were screened and administered with one dose of the vaccine, as group B; Group A were 42 children from one of the villages and administered with 3 doses of the vaccine according to 0, 2, 6 month schedule. Blood samples were taken for the children 1, 2, 6, 7, 8, 12, 24, 36 and 96 months after the administrations respectively and detected for anti-HAV antibody.

RESULTSFor group B, the sero conversion rate of anti-HAV and GMC reached peak at 92.2% and 126.2 mIU/ml respectively, and then, began to drop with time; For group A, after 2 dose of the vaccine, the sero-conversion rate reached 100%, and the GMC reached peak of 2 739 mIU/ml one month after the third dose at 7 months. So that, group A has a better short-term immunological effects than that of group B. During 36 through 96 months, the anti-HAV positive rate in group B was 75%-71% and 80-89 mIU/ml respectively, and comparatively in group A were 100% and 918.2-480.6 mIU/ml respectively. The differences between group A and B were significantly important.

CONCLUSIONA 3-dose schedule administration of H2 strain live attenuated hepatitis A vaccine has better immunological effects than 1-dose schedule in 8years and further observations are needed.

Child ; Child, Preschool ; Female ; Hepatitis A ; blood ; immunology ; prevention & control ; Hepatitis A Antibodies ; blood ; immunology ; Hepatitis A Vaccines ; administration & dosage ; immunology ; Humans ; Immunization Schedule ; Immunization, Secondary ; Infant ; Male ; Vaccines, Attenuated ; administration & dosage ; immunology

OBJECTIVETo study the viremia formation in guinea-pigs infected with wild type and attenuated Japanese encephalitis virus (JEV).

METHODSGuniea pigs were inoculated intraperitoneally with different wild JEV strains and the attenuated vaccine strain and its parent virulent strain. Viremia was detected on different days following virus inoculation.

RESULTSAll the guinea-pigs inoculated with the wild JEV strains induced different levels of viremia (1.00-3.40 Lg pfu) on the 1st and 3rd day post inoculation. Using a virus titer of 10(4) pfu for inoculation, the animals inoculated with the SA14 parent strain induced relatively high viremia (10(2.4)-10(3.4) pfu), however no viremia coulds be detected on any tested days.

CONCLUSIONThe degree of viremia in guinea pigs can be used as a new method to evaluate the attenuation of JEV.

Animals ; Disease Models, Animal ; Encephalitis Virus, Japanese ; pathogenicity ; physiology ; Encephalitis, Japanese ; virology ; Guinea Pigs ; Humans ; Japanese Encephalitis Vaccines ; administration & dosage ; adverse effects ; Vaccines, Attenuated ; administration & dosage ; adverse effects ; Viremia ; virology ; Virulence ; Virus Replication

In order to observe the effect of the immune and weight of chickens after use the attenuated vaccine with low dose of chicken infectious anemia virus (CIAV). In this study, the effects of low dose of CIAV on the weight of SPF chickens and NDV antibody production were observed by simulated experiments. The results showed that 10 EID50 and 5 EID50 CIAV per plume attenuated NDV vaccines were used to cause the weight loss of SPF chickens. Compared with the use of the non contaminated vaccine group, it has significant difference. And NDV antibody levels compared with the use of the non contaminated groups also decreased after use the vaccine with two doses of CIAV contaminated. It has significant difference. A certain proportion of CIAV antibody positive was detected at the beginning of the second week after use the NDV vaccine with two doses of CIAV contaminated. The detection of a high proportion of CIAV nucleic acid was detected in the first week after the use of a contaminated vaccine. The results of the study demonstrate the effects of CIAV pollution on the production and immune function of SPF chickens, and it is suggested that increasing the detection of viral nucleic acid can help save time and improve the detection rate in the detection of exogenous virus contamination by SPF chicken test method.
Animals ; Antibodies, Viral ; immunology ; Chicken anemia virus ; genetics ; immunology ; physiology ; Chickens ; Circoviridae Infections ; immunology ; veterinary ; virology ; Poultry Diseases ; immunology ; virology ; Specific Pathogen-Free Organisms ; Vaccines, Attenuated ; administration & dosage ; genetics ; immunology

OBJECTIVETo establish attenuated Salmonella typhimurium producing Helicobacter pylori (H. pylori) urease subunit B (UreB) and determine whether it could be used as an oral vaccine against H. pylori.

METHODSH. pylori (SS1 strain) UreB gene fragment amplified by PCR was cloned into the prokaryotic expression vector pTC01 after sequencing, and then transformed into attenuated Salmonella typhimurium SL3261 to acquire SL3261/pTC01-UreB. The expression of H. pylori UreB in SL3261 was detected by Western blot. Twelve weeks after oral immunization of mice, antibody responses were evaluated using serum and intestinal fluid by ELISA assay. Interferon-gamma (IFN-gamma) and interleukin-10 (IL-10) in the supernatant of spleen cells culture were also assessed by ELISA. In vitro stability of pTC01-UreB plasmid in SL3261 was confirmed by growing in Luria Broth (LB) medium to 80 generations.

RESULTSThe UreB gene fragment amplified by PCR was consistent with the sequence of the H. pylori UreB as evidenced by sequence analysis. Enzyme digestion revealed that the correct pTC01-UreB was obtained. Western blot showed that a 61kDa protein was expressed in SL3261/pTC01-UreB, which could be recognized by anti-H. pylori UreB antiserum. After 80 generations of continuous culture, the recombinant plasmid pTC01-UreB was stable in SL3261 and had no obvious toxicity. Multiple oral immunizations with SL3261/pTC01-UreB could significantly induce H. pylori-specific mucosal IgA response as well as serum IgG response. Moreover, there were significant increases of IFN-gamma and IL-10 in the SL3261/pTC01-UreB group. Finally, no obvious side effects for mice and no change in gastric inflammation were observed.

CONCLUSIONAttenuated Salmonella typhimurium expressing H. pylori UreB may be used as oral vaccine against H. pylori infection.

Administration, Oral ; Animals ; Antibodies, Bacterial ; blood ; Bacterial Vaccines ; blood ; immunology ; Female ; Helicobacter Infections ; prevention & control ; Helicobacter pylori ; immunology ; Immunization ; Interferon-gamma ; biosynthesis ; Interleukin-10 ; biosynthesis ; Mice ; Mice, Inbred BALB C ; Plasmids ; Protein Subunits ; Salmonella typhimurium ; genetics ; Urease ; immunology ; Vaccines, Attenuated ; immunology ; Vaccines, Synthetic ; immunology

Thirty-nine healthy pigs (28-32 days old) were purchased from a commercial swine farm and housed at swine pens of the College. The animals were vaccinated intramuscularly (1 ml) with an attenuated live hog cholera virus (HCV, LOM strain) and then boostered at 5 weeks after the first vaccination. The animals were divided into 4 experimental groups: 0.05% (w/w) PowerFeel-supplemented diet (T-1, n = 10); 3% (w/w) SuperFeed-supplemented diet (T-2, n = 10); diluted PowerFeel solution (1 : 500, v/v) as drinking water (T-3, n=9); control (n=10). PowerFeel is an original form of ionized alkali mineral complex (IAMC) and SuperFeed is a commercial product of IAMC. The subpopulation of lymphocyte in blood was assayed by a flow cytometry and HCV-specific antibody was determined by an indirect immunofluorescence assay. In IMAC-treated groups, the proportions of subpopulation expressing MHC-class II, CD2+, CD4+, CD8+, and surface IgM+ B lymphocytes were significantly decreased at 5-weeks after the first vaccination. Significant decreases were also observed in the proportions of MHC-class II, CD2+ and CD8+ lymphocyte at 3-weeks after the booster injection. The humoral immune responses in T-1 and T-2 groups were greater than those in T-3 or control group. These results suggest that IAMC-supplemented diets may have an HCV-specific immunostimulatory effect in pigs.
Animal Feed ; Animals ; Antibodies, Monoclonal/*blood/isolation & purification ; Antigens, CD2/blood ; B-Lymphocytes/immunology ; CD4-Positive T-Lymphocytes/immunology ; CD8-Positive T-Lymphocytes/immunology ; Classical Swine Fever/*immunology ; Classical swine fever virus/*immunology ; Dietary Supplements ; Ions ; Lymphocyte Subsets/*immunology ; *Minerals ; Swine ; Vaccines, Attenuated/*administration & dosage ; Viral Vaccines/*administration & dosage