Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 20 de 35
Filter
1.
J Med Virol ; 95(5): e28758, 2023 05.
Article in English | MEDLINE | ID: covidwho-2327008

ABSTRACT

To compare the reactogenicity and immunogenicity between the two-dose mRNA COVID-19 vaccine regimen and one or two doses of inactivated vaccine followed by an mRNA vaccine regimen in healthy children between 5 and 11 years of age, a prospective cohort study was performed at King Chulalongkorn Memorial Hospital in Thailand between March to June 2022. Healthy children between 5 and 11 years of age were enrolled and received the two-dose mRNA COVID-19 vaccine (BNT162b2) regimen or the inactivated (CoronaVac) vaccine followed by the BNT162b2 vaccine regimen. In addition, healthy children who received two doses of BBIBP-CorV between 1 and 3 months prior were enrolled to receive a heterologous BNT162b2 as a third dose (booster). Reactogenicity was assessed by a self-reported online questionnaire. Immunogenicity analysis was performed to determine binding antibodies to wild-type SARS-CoV-2. Neutralizing antibodies to Omicron variants (BA.2 and BA.5) were tested using the focus reduction neutralization test. Overall, 166 eligible children were enrolled. Local and systemic adverse events which occurred within 7 days after vaccination were mild to moderate and well-tolerated. The two-dose BNT162b2, CoronaVac followed by BNT162b2, and two-dose BBIBP-CorV followed by BNT162b2 groups elicited similar levels of anti-receptor-binding domain (RBD) IgG. However, the two-dose BNT162b2 and two-dose BBIBP-CorV followed by BNT162b2 groups elicited higher neutralizing activities against the Omicron BA.2 and BA.5 variant than the CoronaVac followed by BNT162b2 group. The CoronaVac followed by BNT162b2 group elicited low neutralizing activities against the Omicron BA.2 and BA.5 variant. A third dose (booster) mRNA vaccine should be prioritized for this group.


Subject(s)
COVID-19 Vaccines , COVID-19 , Child , Child, Preschool , Humans , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Immunogenicity, Vaccine , Prospective Studies , RNA, Messenger , SARS-CoV-2
2.
PLoS One ; 18(4): e0279147, 2023.
Article in English | MEDLINE | ID: covidwho-2304396

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection can be asymptomatic in young children. Therefore, the true rate of infection is likely underestimated. Few data are available on the rate of infections in young children, and studies on SARS-CoV-2 seroprevalence among children during the omicron wave are limited. We assessed the SARS-CoV-2 infection-induced seroprevalence among children and estimated the associated risk factors for seropositivity. METHODS: A longitudinal serological survey was conducted from January 2021 through December 2022. The inclusion criteria were healthy children between 5 and 7 years old and their parents or legal guardians provided written informed consent. Samples were tested for anti-nucleocapsid (N) IgG and anti-receptor binding domain (RBD) IgG using a chemiluminescent microparticle immunoassay (CMIA), and total anti-RBD immunoglobulin (Ig) was detected using an electrochemiluminescence immunoassay (ECLIA). The vaccination and SARS-CoV-2 infection history were collected. RESULTS: In all, 457 serum samples were obtained from 241 annually followed-up children in this longitudinal serological survey. Of these, 201 participants provided samples at two serial time points-during the pre-omicron and omicron-dominant wave. Overall, seroprevalence induced by SARS-CoV-2 infection increased from 9.1% (22/241) during the pre-omicron to 48.8% (98/201) during the omicron wave. Amongst seropositive individuals, the infection-induced seropositivity was lower in vaccinated participants with two doses of BNT162b2 than in the unvaccinated participants (26.4% vs. 56%; OR, 0.28; 95%CI: 0.14-0.58). Nevertheless, the ratio of seropositive cases per recalled infection was 1.63 during the omicron dominant wave. The overall seroprevalence induced by infection, vaccination, and hybrid immunity was 77.1% (155/201) between January and December 2022. CONCLUSIONS: We report an increase in infection-induced seroprevalence among children during the omicron wave. These findings highlight that a seroprevalence survey can help determine the true rate of infection, particularly in asymptomatic infection, and optimize public health policies and vaccine strategies in the pediatric population.


Subject(s)
COVID-19 , Child , Humans , Child, Preschool , COVID-19/epidemiology , SARS-CoV-2 , Longitudinal Studies , Thailand/epidemiology , BNT162 Vaccine , Seroepidemiologic Studies , Immunoglobulin G , Antibodies, Viral
3.
Vaccines (Basel) ; 11(3)2023 Mar 01.
Article in English | MEDLINE | ID: covidwho-2265451

ABSTRACT

The aim of this study is to investigate the reactogenicity and immunogenicity of the fourth dose using monovalent mRNA vaccines after different three-dose regimens and to compare the 30 µg BNT162b2 and 50 µg mRNA-1273 vaccines. This prospective cohort study was conducted between June and October 2022. The self-recorded reactogenicity was evaluated on the subsequent 7 days after a fourth dose. The binding and neutralizing activity of antibodies against the Omicron BA.4/5 variants were determined. Overall, 292 healthy adults were enrolled and received BNT162b2 or mRNA-1273. Reactogenicity was mild to moderate and well tolerated after a few days. Sixty-five individuals were excluded. Thus, 227 eligible individuals received a fourth booster dose of BNT162b2 (n = 109) and mRNA-1273 (n = 118). Most participants, regardless of the type of previous three-dose regimens, elicited a significantly high level of binding antibodies and neutralizing activity against Omicron BA.4/5 28 days after a fourth dose. The neutralizing activity against Omicron BA.4/5 between the BNT162b2 (82.8%) and mRNA-1273 (84.2%) groups was comparable with a median ratio of 1.02. This study found that the BNT162b2 and mRNA-1273 vaccines can be used as a fourth booster dose for individuals who were previously immunized with any prior three-dose mix-and-match COVID-19 vaccine regimens.

4.
Int J Infect Dis ; 126: 64-72, 2022 Nov 22.
Article in English | MEDLINE | ID: covidwho-2241988

ABSTRACT

OBJECTIVES: To report the safety and immunogenicity profile of a protein subunit vaccine (CovovaxTM) given as a third (booster) dose to individuals primed with different primary vaccine regimens. METHODS: A third dose was administered to individuals with an interval range of 3-10 months after the second dose. The four groups were classified according to their primary vaccine regimens, including two-dose BBIBP-CorV, AZD1222, BNT162b2, and CoronaVac/AZD1222. Immunogenicity analysis was performed to determine binding antibodies, neutralizing activity, and the T-cell responses. RESULTS: Overall, 210 individuals were enrolled and boosted with the CovovaxTM vaccine. The reactogenicity was mild to moderate. Most participants elicited a high level of binding and neutralizing antibody against Wild-type and Omicron variants after the booster dose. In participants who were antinucleocapsid immunoglobulin G-negative from all groups, a booster dose could elicit neutralizing activity to Wild-type and Omicron variants by more than 95% and 70% inhibition at 28 days, respectively. The CovovaxTM vaccine could elicit a cell-mediated immune response. CONCLUSION: The protein subunit vaccine (CovovaxTM) can be proposed as a booster dose after two different priming dose regimens. It has strong immunogenicity and good safety profiles.

5.
Sci Total Environ ; : 160317, 2022 Nov 25.
Article in English | MEDLINE | ID: covidwho-2235224

ABSTRACT

Wastewater-based epidemiology (WBE) complements the clinical surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants' distribution in populations. Many developed nations have established national and regional WBE systems; however, governance and budget constraints could be obstacles for low- and middle-income countries. An urgent need thus exists to identify hotspots to serve as sentinel sites for WBE. We hypothesized that representative wastewater treatment plants (WWTPs) in two international gateway cities, Bangkok and Phuket, Thailand, could be sentineled for SARS-CoV-2 and its variants to reflect the clinical distribution patterns at city level and serve as early indicators of new variants entering the country. Municipal wastewater samples (n = 132) were collected from eight representative municipal WWTPs in Bangkok and Phuket during 19 sampling events from October 2021 to March 2022, which were tested by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) using the US CDC N1 and N2 multiplex and variant (Alpha, Delta, and Omicron BA.1 and BA.2) singleplex assays. The variant detection ratios from Bangkok and Phuket followed similar trends to the national clinical testing data, and each variant's viral loads agreed with the daily new cases (3-d moving average). Omicron BA.1 was detected in Phuket wastewater prior to Bangkok, possibly due to Phuket's WWTPs serving tourist communities. We found that the Omicron BA.1 and BA.2 viral loads predominantly drove the SARS-CoV-2 resurgence. We also noted a shifting pattern in the Bangkok WBE from a 22-d early warning in early 2021 to a near real-time pattern in late 2021. The potential application of tourist hotspots for WBE to indicate the arrival of new variants and re-emerging or unprecedented infectious agents could support tourism-dependent economies by complementing the reduced clinical regulations while maintaining public health protection via wastewater surveillance.

6.
Vaccines (Basel) ; 11(2)2023 Feb 03.
Article in English | MEDLINE | ID: covidwho-2225819

ABSTRACT

Safety data following the COVID-19 booster mRNA vaccine in solid cancer patients are scarce. We prospectively evaluated adverse events after a booster dose of the BNT162b2 vaccine as compared to the mRNA-1273 vaccine in solid malignancy patients who had previously received two doses of ChAdOx1 or heterogenous CoronaVac/ChAdOx1. Data regarding solicited and unsolicited adverse events were collected using questionnaires. The primary endpoint was the difference in incidence and severity of adverse events between BNT162b2 and mRNA-1273 vaccines. A total of 370 subjects were enrolled, including 172 (47%) and 198 (54%) patients receiving booster doses of BNT162b2 and mRNA-1273 vaccines, respectively. The overall incidence of adverse events in the two groups was comparable (BNT162b2 vs. mRNA-1273; 63% vs. 66%, p = 0.6). There was no significant difference in severity, and the majority of adverse events reported were classed as mild to moderate. Tenderness at the injection site was the only reaction that had a statistically higher reported incidence after the mRNA-1273 vaccine than after the BNT162b2 vaccine (56% vs. 41%, p = 0.003). In conclusion, a booster dose of the mRNA vaccine, either BNT162b2 or mRNA-1273, in solid cancer patients previously vaccinated with ChAdOx1 and CoronaVac appears safe, and no new safety concerns were observed.

7.
Vaccines (Basel) ; 10(10)2022 Oct 05.
Article in English | MEDLINE | ID: covidwho-2066622

ABSTRACT

There are limited data available about the durability of the immune response after administration of the widely used adenovirus-vectored ChAdOx1-nCoV-19 vaccine in cancer patients. This prospective longitudinal observational study analyzed follow-up data of immunogenic responses 12 weeks after the second dose of the ChAdOx1-nCoV-19 vaccine in 290 oncological patients compared to healthy controls. The study aimed to assess the persistence of the humoral immune response three months after the second dose, and omicron neutralization was also evaluated. Three months after completion of the second vaccine dose, the geometric mean titer of SARS-CoV-2 binding total Ig statistically decreased by 42% compared to those at 4 weeks, and was lower than that of the healthy control. Six percent of patients became seronegative for anti-RBD total Ig. Only 5% (2 of 40 samples) tested positive for surrogate neutralization against SAR-CoV-2 Omicron BA.2. Across different therapy types, a waning in immunogenicity was observed within three months after the second dose of the ChAdOx1 nCoV-19 vaccine, rendering it insufficient at that point to protect against the SAR-CoV-2 Omicron BA.2 variant.

8.
Vaccines (Basel) ; 10(10)2022 Sep 26.
Article in English | MEDLINE | ID: covidwho-2044051

ABSTRACT

No data regarding the efficacy of a third mRNA vaccine for solid cancer patients previously primed with the heterologous CoronoVac/ChAdOx1 vaccination implemented in Thailand during the shortage of vaccine supply are available. Forty-four cancer patients who previously received the heterologous CoronaVac-ChAdOx1 regimen were boosted with a third mRNA COVID vaccine, either BNT162b2 or mRNA-1273. Anti-RBD IgG was measured immediately before, two weeks after, and four weeks after the third dose. The antibody response was compared to 87 age- and gender-matched cancer patients who were primed with the homologous ChAdOx1/ChAdOx1 regimens. Post-third dose anti-RBD IgG levels significantly increased compared to pre-third dose levels. There was no statistical difference in post-third dose antibody titers or neutralization levels between these two primary series regimens. Treatment with chemotherapy was associated with a lower antibody response compared to endocrine therapy/biologics. Similar antibody levels were observed after a third booster with either BNT162b2 or mRNA-1273 following heterologous CoronaVac/ChAdOx1 vaccination. There was no statistical difference in the immune response following the third-dose vaccination between cancer patients and healthy individuals who received the same heterologous CoronaVac/ChAdOx1 vaccination. In conclusion, a similar degree of enhanced immunogenicity was observed after a third mRNA COVID-19 vaccination in solid cancer patients who previously received the heterologous CoronaVac/ChAdOx1 regimens.

9.
Int J Infect Dis ; 122: 793-801, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-2015439

ABSTRACT

OBJECTIVES: The SARS-CoV-2 Omicron variant presents numerous mutations potentially able to evade neutralizing antibodies (NAbs) elicited by COVID-19 vaccines. Therefore, this study aimed to provide evidence on a heterologous booster strategy to overcome the waning immunity against Omicron variants. METHODS: Participants who completed the Oxford/AstraZeneca (hereafter AZD1222) vaccine dose for 5-7 months were enrolled. The reactogenicity and persistence of immunogenicity in both humoral and cellular response after a homologous or heterologous booster with the AZD1222 and messenger RNA (mRNA) vaccines (BNT162b2, full, or half-dose mRNA-1273) administered 6 months after primary vaccination were determined. RESULTS: A total of 229 individuals enrolled, and waning of immunity was observed 5-7 months after the AZD1222-primed vaccinations. Total receptor-binding domain (RBD) immunoglobulin (Ig) levels, anti-RBD IgG, and focus reduction neutralization test against Omicron BA.1 and BA.2 variants and T cell response peaked at 14-28 days after booster vaccination. Both the full and half dose of mRNA-1273 induced the highest response, followed by BNT162b2 and AZD1222. At 90 days, the persistence of immunogenicity was observed among all mRNA-boosted individuals. Adverse events were acceptable for all vaccines. CONCLUSION: A heterologous mRNA booster provided a significantly superior boost of binding and NAbs levels against the Omicron variant compared with a homologous booster in individuals with AZD1222-primed vaccinations.


Subject(s)
COVID-19 Vaccines , COVID-19 , Adult , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , ChAdOx1 nCoV-19 , Humans , Immunization, Secondary/adverse effects , RNA, Messenger , SARS-CoV-2/genetics , Vaccination
10.
Vaccine ; 40(39): 5657-5663, 2022 09 16.
Article in English | MEDLINE | ID: covidwho-1996611

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has been a serious healthcare problem worldwide since December 2019. The third dose of heterologous vaccine was recently approved by World Health Organization. The present study compared the reactogenicity and immunogenicity of the reduced and standard third booster dose of the BNT162b2 and mRNA-1273 vaccine in adults who previously received the two-dose CoronaVac vaccine. Results showed that headache, joint pain, and diarrhea were more frequent in the 15 µg- than the 30 µg-BNT162b2 groups, whereas joint pain and chilling were more frequent in the 100 µg- than the 50 µg-mRNA-1273 groups. No significant differences in immunogenicity were detected. These findings demonstrate that the reduced dose of the mRNA vaccines elicited antibody responses against the SARS-CoV-2 delta and omicron variants that were comparable to the standard dose. The reduced dose could be used to increase vaccine coverage in situations of limited global vaccine supply.


Subject(s)
COVID-19 Vaccines , COVID-19 , 2019-nCoV Vaccine mRNA-1273 , Adult , Antibodies, Viral , Arthralgia , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Humans , Immunization, Secondary , Immunogenicity, Vaccine , RNA, Messenger , SARS-CoV-2 , Vaccines, Inactivated/adverse effects
11.
EClinicalMedicine ; 52: 101608, 2022 Oct.
Article in English | MEDLINE | ID: covidwho-1982942

ABSTRACT

Background: Limited data exists regarding the efficacy of ChAdOx1-nCoV-19 vaccine against Severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) in solid cancer patients. We aimed to assess the immunogenicity of the ChAdOx1-nCoV-19 vaccine and the impact of different anticancer therapies for solid malignancies on immune response. Methods: This prospective, longitudinal observational study of immunogenicity following ChAdOx1-nCoV-19 vaccination among 385 solid cancer patients on active cancer treatment was conducted in two oncology centers. Participants received the first dose between June 18 and July 27, 2021 and the second dose at 8-10 weeks later. Blood samples were evaluated for total immunoglobulins against the receptor-binding of SARS-CoV-2 spike protein (anti-RBD total-Ig) before, and 4-week after the first- and second-doses. The primary endpoint was the geometric mean titers (GMT) of antibody among solid cancer patients compared to healthy controls and the impact of different cancer treatment types. Findings: Among solid cancer patients, the antibody level increased more slowly to significantly lower levels than achieved in healthy controls. The GMT at 4-weeks post-vaccination in cancer vs. healthy were 224.5 U/ml (95%CI 176.4-285.6) vs. 877.1 U/ml (95%CI 763.5-1008), p<0.0001), respectively. For different types of cancer treatments, chemotherapy agents, especially anthracyclines (GMR 0.004; 95%CI 0.002-0.008), paclitaxel (GMR 0.268; 95%CI 0.123-0.581), oxaliplatin (GMR 0.340; 95%CI 0.165-0.484), and immunotherapy (GMR 0.203; 95%CI 0.109-0.381) showed significantly lower antibody response. Anti-HER2, endocrine therapy and 5-fluouracil or gemcitabine, however, had less impact on the immune response. Interpretation: Suboptimal and heterogeneous immunologic responses were observed in cancer patients being treated with different systemic treatments. Immunotherapy or chemotherapy significantly suppressed the antibody response. Funding: Quality Improvement Fund, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society and Center of Excellence in Clinical Virology at Chulalongkorn University and Chulalongkorn Medical Oncology Research Fund.

13.
J Med Virol ; 94(12): 5713-5722, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1971294

ABSTRACT

The coronavirus 2019 omicron variant has surged rapidly and raises concerns about immune evasion even in individuals with complete vaccination, because it harbors mutations. Here we examine the capability of booster vaccination following CoronaVac/AZD1222 prime to induce neutralizing antibodies (NAbs) against omicron (BA.1 and BA.2) and T-cell responses. A total of 167 participants primed with heterologous CoronaVac/AZD1222 for 4-5 months were enrolled, to receive AZD1222, BNT162b2, or mRNA-1273 as a third dose. Reactogenicity was recorded. Immunogenicity analyses of severe acute respiratory syndrome coronavirus 2-binding antibodies were measured using enzyme-linked immunosorbent assay. The NAb titers against omicron BA.1 and BA.2 were determined using the focus reduction neutralization test (FRNT50) and total interferon-γ responses were measured to observe the T-cell activation. A substantial loss in neutralizing potency to omicron variant was found at 4-5 months after receiving the heterologous CoronaVac/AZD1222. Following booster vaccination, a significant increase in binding antibodies and neutralizing activities toward delta and omicron variants was observed. Neutralization to omicron BA.1 and BA.2 were comparable, showing the highest titers after boosted mRNA-1273 followed by BNT162b2 and AZD1222. In addition, individuals boosted with messenger RNA (mRNA) vaccines develop a T-cell response to spike protein, whereas those boosted with AZD1222 did not. Reactogenicity was mild to moderate without serious adverse events. Our findings demonstrated that mRNA booster vaccination is able to overcome waning immunity to provide antibodies that neutralize omicron BA.1 and BA.2, as well as a T-cell response.


Subject(s)
COVID-19 , Vaccines , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines , ChAdOx1 nCoV-19 , Humans , Immunity , Interferon-gamma , RNA, Messenger/genetics , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Vaccination
14.
Lupus Sci Med ; 9(1)2022 07.
Article in English | MEDLINE | ID: covidwho-1962350

ABSTRACT

OBJECTIVES: To evaluate the safety and immunogenicity of third and fourth BNT162b2 boosters in patients with SLE and rheumatoid arthritis (RA). METHODS: Patients with SLE and RA aged 18-65 years who completed a series of inactivated, adenoviral vector, or heterogenous adenoviral vector/mRNA vaccines for at least 28 days were enrolled. Immunogenicity assessment was done before and day 15 after each booster vaccination. The third BNT162b2 booster was administered on day 1. Patients with suboptimal humoral response to the third booster dose (antireceptor-binding domain (RBD) IgG on day 15 <2360 BAU/mL) were given a fourth BNT162b2 booster on day 22. RESULTS: Seventy-one patients with SLE and 29 patients with RA were enrolled. The third booster raised anti-RBD IgG by 15-fold, and patients with positive neutralising activity against the Omicron variant increased from 0% to 42%. Patients with positive cellular immune response also increased from 55% to 94%. High immunosuppressive load and initial inactivated vaccine were associated with lower anti-RBD IgG titre. Fifty-four patients had suboptimal humoral responses to the third booster and 28 received a fourth booster dose. Although anti-RBD IgG increased further by sevenfold, no significant change in neutralising activity against the Omicron variant was observed. There were two severe SLE flares that occurred shortly after the fourth booster dose. CONCLUSIONS: The third BNT162b2 booster significantly improved humoral and cellular immunogenicity in patients with SLE and RA. The benefit of a short-interval fourth booster in patients with suboptimal humoral response was unclear. TRIAL REGISTRATION NUMBER: TCTR20211220004.


Subject(s)
Arthritis, Rheumatoid , COVID-19 , Lupus Erythematosus, Systemic , BNT162 Vaccine , COVID-19/prevention & control , Humans , Immunity , Immunoglobulin G , Lupus Erythematosus, Systemic/complications , RNA, Messenger , SARS-CoV-2
15.
Diagnostics (Basel) ; 12(8)2022 Jul 22.
Article in English | MEDLINE | ID: covidwho-1957248

ABSTRACT

This study examined the neutralizing activity and receptor-binding domain (RBD) antibody levels against wild-type and omicron BA.1 and BA.2 variants in individuals who received three doses of COVID-19 vaccination. The relationship between the anti-RBD IgG against wild-type and live virus neutralizing antibody titers against omicron BA.1 and BA.2 variants was examined. In total, 310 sera samples from individuals after booster vaccination (third-dose) were tested for specific IgG wild-type SARS-CoV-2 RBD and the omicron BA.1 surrogate virus neutralization test (sVNT). The live virus neutralization assay against omicron BA.1 and BA.2 was performed using the foci-reduction neutralization test (FRNT50). The anti-RBD IgG strongly correlated with FRNT50 titers against BA.1 and BA.2. Non-linear regression showed that anti-RBD IgG at the cut-off value ≥148 BAU/mL and ≥138 BAU/mL were related to the threshold for FRNT50 titers ≥20 against BA.1 and BA.2, respectively. A moderate correlation was observed between the sVNT and FRNT50 titers. At FRNT50 titers ≥20, the predicted sVNT for BA.1 and BA.2 was ≥10.57% and ≥11.52%, respectively. The study identified anti-RBD IgG and sVNT levels that predict detectable neutralizing antibodies against omicron variants. Assessment and monitoring of protective immunity support vaccine policies and will help identify optimal timing for booster vaccination.

17.
Vaccines (Basel) ; 10(7)2022 Jul 03.
Article in English | MEDLINE | ID: covidwho-1917879

ABSTRACT

Coronavirus disease 2019 (COVID-19) booster vaccination is being comprehensively evaluated globally due to waning immunity and the emergence of new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. Therefore, this study aimed to evaluate antibody responses in individuals vaccinated with two doses of the BBIBP-CorV vaccine and to explore the boosting effect of the different vaccine platforms in BBIBP-CorV-primed healthy adults, including a viral vector vaccine (AZD122) and mRNA vaccines (BNT162b2 and mRNA-1273). The results showed that in the BBIBP-CorV prime group, the total receptor-binding domain (RBD) immunoglobulin (Ig) and anti-RBD IgG levels waned significantly at three months after receiving the second dose. However, after the booster, RBD-specific binding antibody levels increased. Neutralizing antibody measured by a surrogate neutralization test showed inhibition over 90% against the SARS-CoV-2 delta variant but less than 70% against the omicron variant after the third dose on day 28. All booster vaccines could induce the total IFN-É£ T-cell response. The reactogenicity was acceptable and well-tolerated without serious adverse events. This study supports the administration of the third dose with either a viral vector or mRNA vaccine for BBIBP-CorV-primed individuals to stimulate antibody and T-cell responses.

18.
PLoS One ; 17(4): e0267102, 2022.
Article in English | MEDLINE | ID: covidwho-1883688

ABSTRACT

Understanding antibody responses after natural severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can guide the coronavirus disease 2019 (COVID-19) vaccine schedule, especially in resource-limited settings. This study aimed to assess the dynamics of SARS-CoV-2 antibodies, including anti-spike protein 1 (S1) immunoglobulin (Ig)G, anti-receptor-binding domain (RBD) total Ig, anti-S1 IgA, and neutralizing antibody against wild-type SARS-CoV-2 over time in a cohort of patients who were previously infected with the wild-type SARS-CoV-2. Between March and May 2020, 531 individuals with virologically confirmed cases of wild-type SARS-CoV-2 infection were enrolled in our immunological study. Blood samples were collected at 3-, 6-, 9-, and 12-months post symptom onset or detection of SARS-CoV-2 by RT-PCR (in asymptomatic individuals). The neutralizing titers against SARS-CoV-2 were detected in 95.2%, 86.7%, 85.0%, and 85.4% of recovered COVID-19 patients at 3, 6, 9, and 12 months after symptom onset, respectively. The seropositivity rate of anti-S1 IgG, anti-RBD total Ig, anti-S1 IgA, and neutralizing titers remained at 68.6%, 89.6%, 77.1%, and 85.4%, respectively, at 12 months after symptom onset. We observed a high level of correlation between neutralizing and SARS-CoV-2 spike protein-specific antibody titers. The half-life of neutralizing titers was estimated at 100.7 days (95% confidence interval = 44.5-327.4 days, R2 = 0.106). These results support that the decline in serum antibody levels over time in both participants with severe disease and mild disease were depended on the symptom severity, and the individuals with high IgG antibody titers experienced a significantly longer persistence of SARS-CoV-2-specific antibody responses than those with lower titers.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19 Vaccines , Humans , Immunoglobulin A , Immunoglobulin G , Spike Glycoprotein, Coronavirus
19.
Vaccines (Basel) ; 10(6)2022 May 26.
Article in English | MEDLINE | ID: covidwho-1869860

ABSTRACT

BACKGROUND: Impaired immune responses to COVID-19 vaccines have been observed in autoimmune rheumatic disease patients. Determining the most effective and safe vaccine regimen is critically needed in such a population. We aim to compare the immunogenicity and safety of three COVID-19 vaccine regimens in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). METHODS: SLE and RA patients aged 18-65 years who received inactivated (CoronaVac or COVILO), adenovirus-vectored (AZD1222), or heterogeneous (AZD1222/BNT162b2) vaccines were enrolled. Humoral and cellular immune responses were assessed at day 28 after the second vaccination. This was performed using the serum binding antibody level against the receptor-binding domain of the SARS-CoV-2 spike protein (anti-RBD Ig) and IFNy-ELISpot assay (ELISpot), respectively. Reactogenicity was reviewed on day 7 following each vaccination. Disease activity was assessed before and on day 28 after the second vaccination. RESULTS: The cohort consisted of 94 patients (64 SLE and 30 RA). Inactivated, AZD1222, and AZD1222/BNT162b2 vaccines were administered to 23, 43, and 28 patients, respectively. Anti-RBD titers were lowest in the inactivated vaccine group (2.84 AU/mL; 95% CI 0.96-8.44), followed by AZD1222 (233.7 AU/mL; 95% CI 99.0-505.5), and AZD1222/BNT162b2 (688.6 AU/mL; 95% CI 271-1745), p < 0.0001. After adjusting for relevant factors, the inactivated vaccine was associated with the lowest humoral response, while adenovirus-vectored/mRNA vaccine was the highest. The proportion of positive ELISpot test was also lowest in the inactivated vaccine group (27%), followed by the adenovirus-vectored vaccine (67%), and the adenovirus-vectored/mRNA vaccine (73%) (p = 0.03). All types of vaccine were well-tolerated. There was no flare of autoimmune disease post-vaccination. CONCLUSION: Adenovirus-vectored and adenovirus-vectored/mRNA vaccines elicited a stronger humoral and cellular immune response than inactivated vaccines, suggesting that they may be more suitable in SLE and RA patients receiving immunosuppressive therapy.

SELECTION OF CITATIONS
SEARCH DETAIL