Food-borne Salmonella outbreak in a single hospital ward.

In June 2012, an outbreak of Salmonella group C gastroenteritis occurred on a single hospital ward among 54.2% (13/24) of volunteers undergoing an unrelated clinical trial and among 14.3% (1/7) hospital ward worker. Food-borne transmission was suspected, so a retrospective cohort study was conducted to identify the vehicle of the outbreak along with implementing outbreak control measures. None of the food items was significantly associated with the outbreak. An epidemic curve suggests a common source of the outbreak. No cases were reported after outbreak control. Food should be stored, cooked and handled using strict hygiene to prevent future outbreaks.

Safety and immunogenicity of an inactivated recombinant Newcastle disease virus vaccine expressing SARS-CoV-2 spike: Interim results of a randomised, placebo-controlled, phase 1 trial.

Background: Production of affordable coronavirus disease 2019 (COVID-19) vaccines in low- and middle-income countries is needed. NDV-HXP-S is an inactivated egg-based recombinant Newcastle disease virus vaccine expressing the spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It's being developed by public sector manufacturers in Thailand, Vietnam, and Brazil; herein are initial results from Thailand. Methods: This phase 1 stage of a randomised, dose-escalation, observer-blind, placebo-controlled, phase 1/2 trial was conducted at the Vaccine Trial Centre, Mahidol University (Bangkok). Healthy males and non-pregnant females, aged 18-59 years and negative for SARS-CoV-2 antibodies, were eligible. Participants were randomised to receive one of six treatments by intramuscular injection twice, 28 days apart: 1 µg, 1 µg+CpG1018 (a toll-like receptor 9 agonist), 3 µg, 3 µg+CpG1018, 10 µg, or placebo. Participants and personnel assessing outcomes were masked to treatment. The primary outcomes were solicited and spontaneously reported adverse events (AEs) during 7 and 28 days after each vaccination, respectively. Secondary outcomes were immunogenicity measures (anti-S IgG and pseudotyped virus neutralisation). An interim analysis assessed safety at day 57 in treatment-exposed individuals and immunogenicity through day 43 per protocol. ClinicalTrials.gov (NCT04764422). Findings: Between March 20 and April 23, 2021, 377 individuals were screened and 210 were enroled (35 per group); all received dose one; five missed dose two. The most common solicited AEs among vaccinees, all predominantly mild, were injection site pain (<63%), fatigue (<35%), headache (<32%), and myalgia (<32%). The proportion reporting a vaccine-related AE ranged from 5·7% to 17·1% among vaccine groups and was 2·9% in controls; there was no vaccine-related serious adverse event. The 10 µg formulation's immunogenicity ranked best, followed by 3 µg+CpG1018, 3 µg, 1 µg+CpG1018, and 1 µg formulations. On day 43, the geometric mean concentrations of 50% neutralising antibody ranged from 122·23 international units per mL (IU/mL; 1 µg, 95% confidence interval (CI) 86·40-172·91) to 474·35 IU/mL (10 µg, 95% CI 320·90-701·19), with 93·9% to 100% of vaccine groups attaining a ≥ 4-fold increase over baseline. Interpretation: NDV-HXP-S had an acceptable safety profile and potent immunogenicity. The 3 µg and 3 µg+CpG1018 formulations advanced to phase 2. Funding: National Vaccine Institute (Thailand), National Research Council (Thailand), Bill & Melinda Gates Foundation, National Institutes of Health (USA).

Safety and Immunogenicity of an Inactivated Recombinant Newcastle Disease Virus Vaccine Expressing SARS-CoV-2 Spike: Interim Results of a Randomised, Placebo-Controlled, Phase 1/2 Trial.

BACKGROUND: Production of affordable coronavirus disease 2019 (COVID-19) vaccines in low- and middle-income countries is needed. NDV-HXP-S is an inactivated egg-based Newcastle disease virus vaccine expressing the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It's being developed in Thailand, Vietnam, and Brazil; herein are initial results from Thailand. METHODS: This phase 1 stage of a randomised, dose-escalation, observer-blind, placebo-controlled, phase 1/2 trial was conducted at the Vaccine Trial Centre, Mahidol University (Bangkok). Healthy adults aged 18-59 years, non-pregnant and negative for SARS-CoV-2 antibodies were eligible. Participants were block randomised to receive one of six treatments by intramuscular injection twice, 28 days apart: 1 µg±CpG1018 (a toll-like receptor 9 agonist), 3 µg±CpG1018, 10 µg, or placebo. Participants and personnel assessing outcomes were masked to treatment. The primary outcomes were solicited and spontaneously reported adverse events (AEs) during 7 and 28 days after each vaccination, respectively. Secondary outcomes were immunogenicity measures (anti-S IgG and pseudotyped virus neutralisation). An interim analysis assessed safety at day 57 in treatment-exposed individuals and immunogenicity through day 43 per protocol. ClinicalTrials.gov ( NCT04764422 ). FINDINGS: Between March 20 and April 23, 2021, 377 individuals were screened and 210 were enrolled (35 per group); all received dose one; five missed dose two. The most common solicited AEs among vaccinees, all predominantly mild, were injection site pain (<63%), fatigue (<35%), headache (<32%), and myalgia (<32%). The proportion reporting a vaccine-related AE ranged from 5·7% to 17·1% among vaccine groups and was 2·9% in controls; there was no vaccine-related serious adverse event. The 10 µg formulation's immunogenicity ranked best, followed by 3 µg+CpG1018, 3 µg, 1 µg+CpG1018, and 1 µg formulations. On day 43, the geometric mean concentrations of 50% neutralising antibody ranged from 122·23 IU/mL (1 µg, 95% CI 86·40-172·91) to 474·35 IU/mL (10 µg, 95% CI 320·90-701·19), with 93·9% to 100% of vaccine groups attaining a ≥4-fold increase over baseline. INTERPRETATION: NDV-HXP-S had an acceptable safety profile and potent immunogenicity. The 3 µg and 3 µg+CpG1018 formulations advanced to phase 2. FUNDING: National Vaccine Institute (Thailand), National Research Council (Thailand), Bill & Melinda Gates Foundation, National Institutes of Health (USA).

Immune responses to intradermal and intramuscular inactivated influenza vaccine among older age group.

BACKGROUD: Influenza viruses cause substantial morbidity, especially in older age groups. Thus, they are amongst high priority groups for routine vaccination. However, vaccine-induced immune responses and effectiveness were reported as relatively low. This study aims to systemically compare the immune responses elicited by intramuscular (IM) and intradermal (ID) injections with inactivated seasonal influenza vaccine among the older age group. METHODS: A prospective, open-label, randomized study with a total of 221 adults (>60 years) were enrolled and randomized into 2 groups. Group I (n = 111) received an IM inactivated seasonal influenza vaccine while Group II (n = 110) received the same vaccine ID. Demographics and co-morbidity were collected at baseline. Safety data was collected 3 days post-vaccination using diary card. HAI, NAb and NAI titers were assessed prior to vaccination and at 30, 45, and 60 days post-vaccination. Data was analyzed using SPSS 11.5. RESULTS: Both groups had similar BMI and co-morbidity. For ID and IM groups, significant differences were observed for seroconversion rate measured using HAI against H1N1 and H3N2 (58/111 vs 44/110 and 68/111 vs 54/110, respectively) being higher for those aged 60-65 years. However, no differences in HI antibody against B/Phuket were seen. For ID route, history of hyperlipidemia and hypertension were factors associated with high seroconversion rate towards influenza A (p = .001). The seroconversion rate risk ratio were 1.31 and 1.25 (p < .05) against A/California/07/09(H1N1) and A/Songkha/308/13 (H3N2), respectively. Interestingly, the GMT (95% CI) of baseline NAI antibodies among both groups were high (56.57 and 54.01 in the ID and IM groups, respectively). A 4-fold increase measured by NAI against A/California/07/09 (H1N1) were detected in 16.67% and 20% of participants who received ID or IM vaccination, respectively. CONCLUSIONS: The seroconversion rates of HAI, NAb and NAI were modest, especially in those >65 years of age. However, it was higher in the ID group as compared to the IM group. CLINICAL TRIAL REGISTRATION: NCT02101749.

6-month evaluation of JinHuang Chinese herbal medicine study in asymptomatic HIV infected Thais.

Good results of in vitro study of anti-HIV effects of JinHuang, a Chinese herbal medicine led to in vivo study of safety and efficacy among asymptomatic HIV infected individuals. It was a prospective open study of 21 asymptomatic HIV infected Thai volunteers. Twelve and 9 were female and male, respectively, with mean age of 29.24 +/- 3.94 years. JinHuang preparation, 6 capsules and 2 bottles of liquid formula orally three times a day, was given on an outpatient basis initially for 6 months. Regular close monitoring and follow-up were done. The side effects reported included : increased bowel movements (81%), vague taste, and smell of drug after initiation (52%). No serious adverse event related to JinHuang was detected during study. No significant changes in terms of log viral load and CD4 count were observed after 6-months' duration. Most of the patients felt that the quality of life was better in terms of better appetite, good sleep and healthy during study participation, however, these were subjective.

Evaluation of attitude, risk behavior and expectations among Thai participants in Phase I/II HIV/AIDS vaccine trials.

The Understanding of volunteers in vaccine trials about their role as study participants and their voluntary commitment during the study are always one of the important concerns apart from evaluation of safety and efficacy of vaccine trials, especially in HIV prophylactic vaccine trials. The apprehension of indirectly risky behavior encouragement and deviated expectations among volunteers should be of concern. The current prospective cohort study aimed to assess and monitor the changes of risk behaviors, attitude and expectations among 164 volunteers from 2 studies of different prophylactic HIV vaccines, the Chiron HIV Thai E gp 120/MF59 +/- the Chiron HIV SF52 gp120 and Aventis Pasteur Live Recombinant ALVAC HIV (vCP1521) priming with VaxGen gp120B/E (AIDSVAX B/E) boosting. 113 males and 51 females with a mean age (+/- SD) of 28.82 +/- 7.97 years old were enrolled from October 1997 to December 1998 and February 2000 to April 2001. Education and risk reduction counseling were regularly performed at every visit and questionnaires about risk behaviors, knowledge, attitudes, social influences and expectations were asked at baseline, 4 months and 12 months. No change of potentially HIV transmission related risk behavior was observed during the studies. There was a statistically significant decrease of risk sexual practices from the beginning of the trials (42.2% vs 1%, p < 0.0001). While 35.2 per cent from 62.2 per cent of the volunteers at the beginning of the study continued sexual practice with an identified single sexual partner at the end of the study (p < 0.0001). All of the volunteers expressed the beneficial expectations as knowledge gain, social contribution, feelings of having gained merit and self-benefits from health check-ups.