Porcine epidemic diarrhea viruses from Vietnam: isolation, characterization, and neutralizing activity

Porcine epidemic diarrhea (PED) is characterized by acute enteritis, watery diarrhea, weight loss, dehydration, and death, with high mortality in neonatal piglets. In this study, 3 virus isolates collected in Vietnam between 2016 and 2017 were propagated successfully in Vero cells at high virus titers. Sequence analysis of the full-length spike (S) gene showed that all 3 isolates belong to genogroup 2b, which is closely related to other prevalent Asian strains. A comparison of the amino acid sequence revealed a 98.19% to 99.13% homology with the Vietnam isolates circulating during 2013–2015, suggesting that field PED viruses (PEDVs) are evolving continuously. Experiments in animals showed that the antisera from guinea pigs immunized with the vaccine strain resulted in higher levels (5 log2) of neutralizing antibodies against the homologous strain and a relatively moderate level of neutralizing antibodies against the field isolates. This finding would be helpful in selecting a PEDV strain for vaccine development.

Isolation, characterization and neutralizing activity of porcine epidemic diarrhea viruses from Vietnam

Porcine epidemic diarrhea (PED) is characterized by acute enteritis, watery diarrhea, weight loss, dehydration, and death with high mortality in neonatal piglets. In this study, 3 virus isolates collected in Vietnam between 2016 and 2017 were successfully propagated in Vero cells at high virus titers. Sequence analysis of the full-length spike (S) gene revealed that all 3 isolates belong to genogroup 2a, which is closely related to other prevalent Asian strains. Amino acid sequence comparisons revealed 98.19% to 99.13% homology with the Vietnam isolates circulating during 2013–2015, suggesting that field PED viruses (PEDVs) evolve continuously. Experiments in animals demonstrated that antisera from guinea pigs immunized with the vaccine strain resulted in higher levels (5 log2) of neutralizing antibody against the homologous strain, and showed a relatively lower level of neutralizing antibody against the field isolates. This finding would be helpful in choosing a PEDV strain for vaccine development.

Anaplasma marginale and A. platys Characterized from Dairy and Indigenous Cattle and Dogs in Northern Vietnam

Anaplasma marginale and A. platys were detected and characterized (16S rDNA sequence analysis) from dairy and indigenous cattle, and the latter in domestic dogs in Vietnam. A phylogenetic tree was inferred from 26 representative strains/species of Anaplasma spp. including 10 new sequences from Vietnam. Seven of our Vietnamese sequences fell into the clade of A. marginale and 3 into A. platys, with strong nodal support of 99 and 90%, respectively. Low genetic distances (0.2–0.4%) within each species supported the identification. Anaplasma platys is able to infect humans. Our discovery of this species in cattle and domestic dogs raises considerable concern about zoonotic transmission in Vietnam. Further systematic investigations are needed to gain data for Anaplasma spp. and members of Anaplasmataceae in animal hosts, vectors and humans across Vietnam.

Study of production of inactivated influenza vaccine for human on egg-grown from reassortants NIBRG-14 at vaccine institute

Background: A/H5N1 influenza virus spreads from birds to humans and cause influenza diseases with high mortality rate. Vaccination is the most effective way to protect communities from pandemic, reduce morbidity and mortality. The study of creating A/H5N1 influenza vaccines in conformity with Vietnam was the urgent need. Institute of Vaccine\u2019s Achievement (IVAC) studied production of inactivated influenza vaccine for human on egg-grown from reassortants NIBRG-14. Objectives: In order to produce experimentally A/H5N1 influenza vaccine for human in accordance with WHO requirements and set up a viable process for production of the vaccines. Subjects and method: 10 days embryonated eggs and NIBRG-14 strains were served to the study with LAL method to check endotoxin, Kijehdal method to test total protein. Results: IVAC had produced successfully 5 lots of absorbed vaccine A/H5N1 (FLUVAC) using NIBRG-14 strains and embryonated eggs. Initially, production and quality control processes had been set up at IVAC by applying the recommendations of WHO. Conclusion: The success of the study was a basis of the approval of the government to establish a influenza vaccine manufacturing facilities.

Dyscoagulation on the patients with acute leukemia

The study involved 60 patients with acute leukemia at B¹ch Mai Hospital between June and December 2000. Among these, there were 33 males and 27 females. Findings: 65% of patients have hemorrhage; 88.3% have reduction in platelet count. There was the correlation between reduction in platelet count and symptoms of hemorrhage, with the rate of hemorrhage was 84.6% when number of platelet reduced by less than 30G/l. 46% of patients have endogenous dyscoagulation and 23% have exogenous dyscoagulation. DIC was found in 28.3% of patients. Hemorrhage in acute leukemia also related to dyscoagulation.