Safety and immunogenicity of the third and fourth doses of vaccine against SARS-CoV-2 following a 2-dose regimen of inactivated whole-virion SARS-CoV-2 vaccine.

This study followed healthcare personnel (HCP) who had completed a primary series of CoronaVac and then received the third and fourth doses of COVID-19 vaccine. The primary objective was to determine the seroconversion rate of neutralizing antibodies against wild-type SARS-CoV-2 and VOCs at day 28 after the third dose of vaccine and day 28 after the fourth dose of vaccine. This prospective cohort study was conducted at Maharaj Nakorn Chiang Mai Hospital, a tertiary care hospital affiliated to Chiang Mai University from July 2021 to February 2022. Two hundred and eighty-three participants were assessed for eligibility; 142 had received AZD1222 and 141 BNT162b2 as the third dose. Seroconversion rates using a 30% inhibition cutoff value against wild-type SARS-CoV-2 were 57.2%, 98.6%, 97.8%, and 98.9% at points before and after the third dose, before and after the fourth dose, respectively among those receiving AZD1222 as the third dose. Frequencies were 31.9%, 99.3%, 98.9%, and 100% among those receiving BNT162b2 as the third dose, respectively. The seroconversion rates against B.1.1.529 [Omicron] were 76.1% and 90.2% (p-value 0.010) at 4 weeks after the third dose in those receiving AZD1222 and BNT162b2 as the third dose, respectively. After a booster with the mRNA vaccine, the seroconversion rates increased from 21.7 to 91.3% and from 30.4 to 91.3% in those receiving AZD1222 and BNT162b2 as the third dose, respectively. No serious safety concerns were found in this study. In conclusion, antibody responses waned over time regardless of the vaccine regimen. The booster dose of the vaccine elicited a humoral immune response against SARS-CoV-2 including SARS-CoV-2 variants of concern, including B.1.1.529 [Omicron], which was circulating during the study period. However, the results might not be extrapolated to other Omicron sublineages.

Itraconazole vs fluconazole as a primary prophylaxis for fungal infections in HIV-infected patients in Thailand.

BACKGROUND: Disseminated fungal infections are common presenting opportunistic infections among AIDS patients in developing countries. Primary prophylaxis with itraconazole has been shown to be effective in northern Thailand. This study aimed to compare the efficacy of fluconazole vs itraconazole as primary prophylaxis for fungal infections in HIV-infected patients. METHODS: A retrospective cohort study was conducted among HIV-infected patients who received primary prophylaxis with fluconazole 400 mg once weekly or itraconazole 200 mg once daily at Chiang Mai University Hospital. We compared the incidence of systemic fungal infections and the probability of disease-free survival between groups. RESULTS: From January 2000 to June 2010, 308 HIV-infected patients who received primary fungal prophylaxis were enrolled; 148 were male (48.1%) and the mean age was 38.2 ± 8.0 years. 276 patients received fluconazole and 32 received itraconazole. Baseline CD4+ cell count was 35 (IQR 15, 70) and 50 (IQR 21,75) cells/mm(3) in fluconazole and itraconazole groups, respectively (p=0.159). The median follow-up time was 12 months (IQR 7, 19) in fluconazole group and 15.5 months (IQR 9, 21.5) in itraconazole group. Seven patients (2.5%) who received fluconazole and 2 patients (6.3%) who received itraconazole developed systemic fungal infections, giving the incidence of 17.0 and 34.8/10000 person-months, respectively (p=0.261). The probability of developing any systemic fungal infections or death did not differ between groups. CONCLUSIONS: Although P. marneffei has a reduced susceptibility in in vitro to fluconazole, our study has demonstrated that once-weekly fluconazole is at least as effective as once-daily itraconazole as primary prophylaxis for systemic fungal infections in AIDS patients in northern Thailand.