Breakthrough infections, hospital admissions, and mortality after major COVID-19 vaccination profiles: A prospective cohort study.

Background: Several COVID-19 vaccination rollout strategies are implemented. Real-world data from the large-scale, government-mandated Central Vaccination Center (CVC), Thailand, could be used for comparing the breakthrough infection, across all available COVID-19 vaccination profiles. Methods: This prospective cohort study combined the vaccine profiles from the CVC registry with three nationally validated outcome datasets to assess the breakthrough COVID-19 infection, hospitalization, and death among Thais individuals who received at least one dose of the COVID-19 vaccine. The outcomes were analyzed by comparing vaccine profiles to investigate the shot effect and homologous effect. Findings: Of 2,407,315 Thais who had at least one dose of COVID-19 vaccine, 63,469 (2.75%) had breakthrough infection, 42,001 (1.79%) had been hospitalized, and 431 (0.02%) died. Per one vaccination shot added, there was an 18% risk reduction of breakthrough infection (adjusted hazard ratio [HR] 0.82, 95% confidence interval [CI] 0.80-0.82), a 25% risk reduction of hospitalization (HR 0.75, 95% CI 0.73-0.76), and a 96% risk reduction of mortality (HR 0.04, 95% CI 0.03-0.06). The heterologous two-shot vaccine profiles had a higher protective effect against infection, hospitalization, and mortality compared to the homologous counterparts. Interpretation: COVID-19 breakthrough infection, hospitalization, and death differ across vaccination profiles that had a different number of shots and types of vaccines. Funding: This study did not involve any funding.

ChAdOx1 nCoV-19 Immunogenicity and Immunological Response Following COVID-19 Infection in Patients Receiving Maintenance Hemodialysis.

Patients with end-stage renal disease (ESRD) receiving hemodialysis (HD) were found to have a decreased immune response following mRNA COVID-19 immunization. ChAdOx1 nCoV-19 was a promising COVID-19 vaccine that performed well in the general population, but the evidence on immunogenicity in ESRD with HD patients was limited. Moreover, the immunological response to COVID-19 infection was inconclusive in patients with ESRD and HD. The aim of this study was to investigate the immunogenicity of ChAdOx1 nCoV-19 vaccination and the immunological response after COVID-19 infection in ESRD patients with HD. The blood samples were obtained at baseline, 1-month, and 3-month follow-up after each shot or recovery. All participants were measured for anti-spike IgG by the ELISA method, using Euroimmun. This study found a significant increase in anti-spike IgG after 1 month of two-shot ChAdOx1 nCoV-19 vaccination, followed by a significant decrease after 3 months. On the other hand, the anti-spike IgG was maintained in the post-recovery group. There was no significant difference in the change of anti-spike IgG between the one-shot ChAdOx1 nCoV-19-vaccinated and post-recovery groups for both 1-month and 3-month follow-ups. The seroconversion rate for the vaccinated group was 60.32% at 1 month after one-shot vaccination and slightly dropped to 58.73% at the 3-month follow-up, then was 92.06% at 1 month after two-shot vaccination and reduced to 82.26% at the 3-month follow-up. For the recovered group, the seroconversion rate was 95.65% at 1 month post-recovery and 92.50% at 3-month follow-up. This study demonstrated the immunogenicity of two-dose ChAdOx1 nCoV-19 in ESRD patients with HD for humoral immunity. After COVID-19 infection, the humoral immune response was strong and could be maintained for at least three months.

Multisystem inflammatory syndrome in an adult with severe hypoxaemia and thyroiditis responsive to corticosteroid and interleukin 6 inhibitor treatment.

Multisystem inflammatory syndrome in adults (MIS-A) has been reported as a rare but severe consequence of COVID-19 infection. Adult patients were more likely to present with hypotension and cardiac illness when compared with multisystem inflammatory syndrome in children. Although the exact prevalence of MIS-A is unknown, more cases have been observed in men and younger adults. The pathophysiology of MIS-A is also unclear, but is thought to be caused by a delayed, dysregulated immune response. Given no established guideline for treatment of MIS-A, treatment has been based on case reports. We present a case of MIS-A in a woman in her 60s who had severe hypotension, progressive dyspnoea, massive pleural effusion, hypoxaemia, thyroiditis and multiple organ failure, which dramatically improved after treatment with corticosteroid and interleukin 6 inhibitor.

An epidemiology-based model for the operational allocation of COVID-19 vaccines: A case study of Thailand.

This paper addresses a framework for the operational allocation and administration of COVID-19 vaccines in Thailand, based on both COVID-19 transmission dynamics and other vital operational restrictions that might affect the effectiveness of vaccination strategies in the early stage of vaccine rollout. In this framework, the SIQRV model is first developed and later combined with the COVID-19 Vaccine Allocation Problem (CVAP) to determine the optimal allocation/administration strategies that minimize total weighted strain on the whole healthcare system. According to Thailand's second pandemic wave data (17th January 2021, to 15th February 2021), we find that the epicenter-based strategy is surprisingly the worst allocation strategy, due largely to the negligence of provincial demographics, vaccine efficacy, and overall transmission dynamics that lead to higher number of infectious individuals. We also find that early vaccination seems to significantly contribute to the reduction in the number of infectious individuals, whose effects tend to increase with more vaccine supply. With these insights, healthcare policy-makers should therefore focus not only on the procurement of COVID-19 vaccines at strategic levels but also on the allocation and administration of such vaccines at operational levels for the best of their limited vaccine supply.

Peritoneal dialysis care during the COVID-19 pandemic, Thailand.

PROBLEM: The coronavirus disease 2019 (COVID-19) pandemic could affect health service provision of less urgent interventions, such as peritoneal dialysis for chronic kidney disease patients. APPROACH: To assess how peritoneal dialysis centres in Thailand adapted their provision of care, we invited medical directors and peritoneal dialysis managers to respond to an online survey on 1 July 2021. We asked whether they had modified or deferred their training, catheter insertion or removal, intravenous supplements, follow-up and home visits, and workload. LOCAL SETTING: Patients needing dialysis receive peritoneal dialysis free of charge in Thailand. As of 31 December 2020, 240 peritoneal dialysis centres in Thailand have provided care to 32 284 patients. RELEVANT CHANGES: At 24.6% (29/118) of centres, educational sessions for patients were modified. Catheter insertion continued at 71.9% (82/114) of centres. Few facilities (19.7%; 23/117) continued to perform peritoneal equilibration tests as usual. On-site intravenous injections were mostly transferred to health centres close to the patients' homes. Most centres reduced their outpatient follow-up visits (51.7%; 61/118) and stopped visiting patients at home (66.9%; 79/118). Peritoneal dialysis nurses reported an increased workload at 62.7% (74/118) of centres, and in many instances (66.1%; 78/118) were providing nursing care to COVID-19 patients and administering COVID-19 vaccines. LESSONS LEARNT: Health-care providers altered clinical care activities to protect their patients from COVID-19. However, further evidence is needed on the consequences of such alteration in care. To prepare for future pandemics, actors need to explore nonconventional peritoneal dialysis care as well as financial and nonfinancial incentive mechanisms for such care.

Immunogenicity of ChAdOx1 nCoV-19 Booster Vaccination Following Two CoronaVac Shots in Healthcare Workers.

During the early phase of the COVID-19 pandemic, several countries, including Thailand, provided two shots of CoronaVac to healthcare workers. Whereas ChAdOx1 nCoV-19 is the promising vaccine as the booster dose, the data on immunogenicity when administered after CoronaVac have been limited. The purpose of this study was to evaluate the immunogenicity of ChAdOx1 nCoV-19 as the third dose vaccine in healthcare workers who previously received two shots of CoronaVac. The blood samples were obtained before the third vaccination dose, and one month and three months after vaccination. All participants were measured for humoral immunity including anti-spike IgG and neutralizing antibody by ELISA. Twenty participants were stratified by random samples based on baseline IgG status for a cellular immunity function test at three-month post-vaccination, which included T cell and B cell functions by ELISpot. This study showed significant improvement for both humoral and cellular immunity one month after vaccination. Subgroup analysis indicated a significantly higher neutralizing antibody improvement for the population with a negative anti-spike IgG at baseline. Our study suggests that, while immunity level declines at three months post-vaccination, the level was sufficiently high to protect against SARS-CoV-2.

COVID-19 seroprevalence among hospital staff and preprocedural patients in Thai community hospitals: a cross-sectional study.

OBJECTIVES: We aimed to explore the seroprevalence of hospital staff comparing to preprocedural patients in Thai community hospitals to shed light on the situation of COVID-19 infection of frontline healthcare workers in low infection rate countries where mass screening was not readily available. DESIGN: Cross-sectional study. SETTING: 52 community hospitals in 35 provinces covered all regions of Thailand. PARTICIPANTS: 857 participants consisted of 675 hospital staff and 182 preprocedural patients. OUTCOME MEASURE: COVID-19 seroprevalence using a locally developed rapid IgM/IgG test kit RESULTS: Overall, 5.5% of the participants (47 of 857) had positive IgM, 0.2% (2 of 857) had positive IgG which both of them also had positive IgM. Hospitals located in the central part of Thailand had the highest IgM seroprevalence (11.9%). Preprocedural patients had a higher rate of positive IgM than the hospital staff (12.1% vs 3.7%). Participants with present upper respiratory tract symptoms had a higher rate of positive IgM than those without (9.6% vs 4.5%). Three quarters (80.5%, 690 of 857) of the participants were asymptomatic, of which, 31 had positive IgM (4.5%) which consisted of 20 of 566 healthcare workers (3.5%) and 11 of 124 preprocedural patients (8.9%). CONCLUSIONS: COVID-19 antibody test could detect a substantial number of potential silent spreaders in Thai community hospitals where the nasopharyngeal PCR was not readily available, and the antigen test was prohibited. Antibody testing should be encouraged for mass screening in a limited resource setting, especially in asymptomatic individuals. TRIAL REGISTRATION: TCTR20200426002.

Roles of subdistrict health office personnel and village health volunteers in Thailand during the COVID-19 pandemic.

In Thailand, 40 000 subdistrict health centre (SDHC) personnel and >1 million village health volunteers (VHVs) are responsible for primary healthcare of 23 million households in 75 032 villages. They were trained, made household visits, gave hygiene advice, participated in the 'Big Cleaning Day' campaign, produced cloth face masks, proactively identified high-risk visitors and monitored quarantined cases. 7.4 million Thais received basic education on hygiene, 1.3 million villagers joined the campaign and 3.6 million handmade cloth face masks were produced. In March 2020, 3.9 million households were visited, and 40 000 high-risk cases were detected. The intensity of proactive case findings increased to 12.6 million home visits and 834 000 cases were detected in April 2020. Almost 800 000 cases complied with the 14-day mandatory home quarantine, of which 3.6% developed symptoms suspected of respiratory tract infection. VHVs and SDHC personnel could efficiently contribute to the prevention and control of COVID-19 in Thailand.

Intradermal ChAdOx1 Vaccine Following Two CoronaVac Shots: A Case Report.

Inactivated SARS-CoV-2 vaccines are used in many countries with uncertain immunogenicity. Intradermal ChAdOx1 has been proposed as a resource-efficient heterologous third booster shot. A 52-year-old healthy male healthcare professional had received two intramuscular CoronaVac shots on 21 April and 23 May 2021, and volunteered to take a 0.1 mL ChAdOx1 vaccine intradermally on 29 June 2021, with minimal local reactions. The declining IgG levels against spike protein from the two CoronaVac shots increased to higher than 10,000 AU/mL two weeks after the intradermal ChAdOx1. Moreover, the neutralizing antibody increased from 66.77% to almost 100%. A ratio of 6.6:9.7 of IgA:IgG was observed. The 50% pseudovirus neutralization titer (PVNT50) against lentiviral pseudovirus bearing a codon-optimized spike gene (wild type, alpha, beta, and delta) were 1812.42, 822.99, 1025.42, 1347.13, respectively. The SARS-CoV-2-specific T cells to spike protein-peptide pools (532-788 SFU/106 PBMCs) were detected. In conclusion, the antibody and cellular responses to the intradermal ChAdOx1, as a third booster dose in a healthy volunteer who received two intramuscular CoronaVac shots, revealed a dramatic increase in the total antibodies, including IgG, IgA, as well as T cell responses against spike protein. The immune response from intradermal ChAdOx1 should be further investigated in a larger population.

Covid-19 in end-stage renal disease patients with renal replacement therapies: A systematic review and meta-analysis.

BACKGROUND: The novel coronavirus (COVID-19), caused by SARS-CoV-2, showed various prevalence and case-fatality rates (CFR) among patients with different pre-existing chronic conditions. End-stage renal disease (ESRD) patients with renal replacement therapy (RRT) might have a higher prevalence and CFR due to reduced immune function from uremia and kidney tropism of SARS-CoV-2, but there was a lack of systematic study on the infection and mortality of the SARS-CoV-2 infection in ESRD patients with various RRT. METHODOLOGY/PRINCIPAL FINDINGS: We searched five electronic databases and performed a systematic review and meta-analysis up to June 30, 2020, to evaluate the prevalence and case fatality rate (CFR) of the COVID-19 infection among ESRD patients with RRT. The global COVID-19 data were retrieved from the international database on June 30, 2020, for estimating the prevalence and CFR of the general population as referencing points. Of 3,272 potential studies, 34 were eligible studies consisted of 1,944 COVID-19 confirmed cases in 21,873 ESRD patients with RRT from 12 countries in four WHO regions. The overall pooled prevalence in ESRD patients with RRT was 3.10% [95% confidence interval (CI) 1.25-5.72] which was higher than referencing 0.14% global average prevalence. The overall estimated CFR of COVID-19 in ESRD patients with RRT was 18.06% (95% CI 14.09-22.32) which was higher than the global average at 4.98%. CONCLUSIONS: This meta-analysis suggested high COVID-19 prevalence and CFR in ESRD patients with RRT. ESRD patients with RRT should have their specific protocol of COVID-19 prevention and treatment to mitigate excess cases and deaths.

Seroprevalence of hospital staff in a province with zero COVID-19 cases.

BACKGROUND: COVID-19 seroprevalence data, particularly in less developed countries with a relatively low incidence, has been scant. We aimed to explore the seroprevalence of hospital staff in the area with zero confirmed COVID-19 case to shed light on the situation of COVID-19 infection in zero or low infection rate countries where mass screening was not readily available. METHODS: A locally developed rapid immunoglobulin M (IgM)/immunoglobulin G (IgG) test kit was used for hospital staff screening of Ranong hospital which is located in a province with zero COVID-19 prevalence in Thailand from 17th April to 17th May 2020. All staff was tested, 100 of which were randomly invited to have a repeating antibody test in one month. (Thai Clinical Trials Registry: TCTR20200426002). RESULTS: Of 844 hospital staff, 82 were tested twice one month apart (response rate for repeating antibody test 82%). Overall, 0.8% of the participants (7 of 844) had positive IgM, none had positive IgG. Female staff had 1.0% positive IgM (95% CI: 0.5-2.1%) while male had 0.5% positive IgM (95% CI: 0.1-2.6%). No participants with a history of travel to the high-risk area or close contact with PCR-confirmed COVID-19 case developed SARS-CoV-2 antibodies. Among 844 staff, 811 had no symptoms and six of them developed IgM seropositive (0.7%) while 33 had minor symptoms and only one of them developed IgM seropositive (3.0%). No association between SARS-CoV-2 IgM status and gender, history of travel to a high-risk area, close contact with PCR-confirmed or suspected COVID-19 case, presence of symptoms within 14 days, or previous PCR status was found. None of the hospital staff developed SARS-CoV-2 IgG. CONCLUSIONS: COVID-19 antibody test could detect a considerable number of hospital staff who could be potential silent spreaders in a province with zero COVID-19 cases. Accurate antibody testing is a valuable screening tool, particularly in asymptomatic healthcare workers. Trial registration: This study was approved by the Institutional Review Board of Chulalongkorn University (IRB No.236/63) and the Institutional Review Board of Ranong Hospital. (Thai Clinical Trials Registry: TCTR20200426002).

Social restriction versus herd immunity policies in the early phase of the SARS-CoV-2 pandemic: A mathematical modelling study.

BACKGROUND: Two main strategies to cope with the coronavirus disease 2019 (COVID-19) pandemic-lockdown (social restriction) and non-lockdown (herd immunity plan)-have been implemented in several countries. OBJECTIVE: This study aims to statistically compare the outcomes of the two strategies, represented by data from Thailand and Sweden, respectively. METHODS: Data for COVID-19 pandemic control from Thailand, representing social restriction, versus data from Sweden, representing the herd immunity plan, collected from January 13 to May 31, 2020, were analyzed by using the SIR (susceptible, infectious, recovered) model. RESULTS: The SIR model analysis demonstrated a beneficial effect of each model on the attenuation of the mortality rate, with lower mortality in social restriction and shorter overall pandemic duration in the herd immunity plan. However, the herd immunity plan demonstrated a higher mortality rate than social restriction (46.9% versus 1.9%) despite the later entry of the virus in Sweden. When the SIR model was used for predicting the COVID-19 status, Sweden was shown to likely end its COVID-19 epidemic earlier than Thailand (268 vs. 368 days). With the nonlinear estimation, at least one log difference between total confirmed cases versus active cases could be used as an indicator for relaxation of the lockdown policy in Thailand. CONCLUSIONS: Both the social restriction and herd immunity plans are beneficial for COVID-19 pandemic control in terms of the amelioration of pandemic mortality. The cumulative number of total recovered cases might be a potential parameter that could be used for determining the policy direction for COVID-19 control.

Clinical course and potential predictive factors for pneumonia of adult patients with Coronavirus Disease 2019 (COVID-19): A retrospective observational analysis of 193 confirmed cases in Thailand.

Clinical spectrum of Coronavirus Disease 2019 (COVID-19) remains unclear, especially with regard to the presence of pneumonia. We aimed to describe the clinical course and final outcomes of adult patients with laboratory-confirmed COVID-19 in the full spectrum of disease severity. We also aimed to identify potential predictive factors for COVID-19 pneumonia. We conducted a retrospective study among adult patients with laboratory-confirmed COVID-19 who were hospitalized at Bamrasnaradura Infectious Diseases Institute, Thailand, between January 8 and April 16, 2020. One-hundred-and-ninety-three patients were included. The median (IQR) age was 37.0 (29.0-53.0) years, and 58.5% were male. The median (IQR) incubation period was 5.5 (3.0-8.0) days. More than half (56%) of the patients were mild disease severity, 22% were moderate, 14% were severe, and 3% were critical. Asymptomatic infection was found in 5%. The final clinical outcomes in 189 (97.9%) were recovered and 4 (2.1%) were deceased. The incidence of pneumonia was 39%. The median (IQR) time from onset of illness to pneumonia detection was 7.0 (5.0-9.0) days. Bilateral pneumonia was more prevalent than unilateral pneumonia. In multivariable logistic regression, increasing age (OR 2.55 per 10-year increase from 30 years old; 95% CI, 1.67-3.90; p<0.001), obesity (OR 8.74; 95%CI, 2.06-37.18; p = 0.003), and higher temperature at presentation (OR 4.59 per 1°C increase from 37.2°C; 95% CI, 2.30-9.17; p<0.001) were potential predictive factors for COVID-19 pneumonia. Across the spectrum of disease severities, most patients with COVID-19 in our cohort had good final clinical outcomes. COVID-19 pneumonia was found in one-third of them. Older age, obesity, and higher fever at presentation were independent predictors of COVID-19 pneumonia.

Adjunctive favipiravir for severe COVID-19: a retrospective observational study of the first 41 patients in Thailand

Background: Favipiravir is a promising drug for COVID-19, but evidence from a robust clinical trial is limited. Objective: To describe the demographics, clinical characteristics, and various antiviral treatment regimens (with and without favipiravir) of patients with severe and nonsevere COVID-19. Method: We conducted a retrospective observational study in all COVID-19 patients admitted at Bamrasnaradura Infectious Diseases Institute (BIDI) from January 8 to March 30, 2020. We compared the demographics, clinical characteristics, and various antiviral treatment regimens of 12 severe and 29 nonsevere COVID-19 patients in Thailand. Results: Adjunctive favipiravir was given to only severe cases. The median length of hospitalization of patients either receiving favipiravir or not receiving favipiravir was not significantly different (P = 0.8549), but those who received adjunctive favipiravir became reverse transcriptase-polymerase chain reaction negative 2 days sooner than the other group (median: 6 days vs. 8 days;P = 0.1125). Conclusion: The findings suggested that adjunctive favipiravir might not be effective for patients with severe COVID-19, but further studies with larger sample sizes are needed.

Commercial airline protocol during COVID-19 pandemic: An experience of Thai Airways International.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) pandemic has affected the aviation industry. Existing protocols have relied on scientifically questionable evidence and might not lead to the optimal balance between public health safety and airlines' financial viability. OBJECTIVE: To explore the implementation feasibility of Thai Airways International protocol from the perspectives of passengers and aircrews. DESIGN: An online questionnaire survey of passengers and an in-depth interview with aircrews. SETTING: Two randomly selected repatriation flights operated by Thai Airways International using Boeing 777 aircraft (TG476 from Sydney and TG492 from Auckland to Bangkok). PARTICIPANTS: 377 Thai passengers and 35 aircrews. RESULTS: The mean age of passengers was 28.14 (95%CI 26.72 to 29.55) years old; 57.03% were female. TG492 passengers were mostly students and significantly younger than that of TG476 (p<0.0001) with comparable flying experience (p = 0.1192). The average body temperature was 36.52 (95%CI 36.48 to 36.55) degrees Celsius. Passengers estimated average physical distances of 1.59 (95%CI 1.48 to 1.70), 1.41 (95%CI 1.29 to 1.53), and 1.26 (95%CI 1.12 to 1.41) meters at check-in, boarding, and in-flight, respectively. Passengers were checked for body temperature during the flight 1.97 (95%CI 1.77 to 2.18) times on average which is significantly more frequent in longer than shorter flight (p<0.0001). Passengers moved around or went to the toilet during the flight 2.00 (95%CI 1.63 to 2.37) and 2.08 (95%CI 1.73 to 2.43) times which are significantly more frequent in longer than shorter flight (p = 0.0186 and 0.0049, respectively). The aircrews were satisfied with the protocol and provided several practical suggestions. CONCLUSION: The protocol was well received by the passengers and aircrews of the repatriation flights with some suggestions for improvement.

Potential dual dengue and SARS-CoV-2 infection in Thailand: A case study.

Coronavirus disease 2019 (Covid-19) has non-specific clinical and laboratory characteristics that might be similar to other viral infection including dengue. Two Covid-19 cases with 'false-positive' dengue serology have been reported in Singapore but no public health consequence was described. We describe a Thai patient with an initial diagnosis of dengue fever who was later confirmed to also infect with SARSCoV-2. The Covid-19 infection appeared to spread to one family member and one healthcare worker.

Nurse infected with Covid-19 from a provisional dengue patient.

We report a 35-year-old female nurse who possibly received the SARS-CoV-2 virus during the blood sampling of a 35-year-old male patient initially suspected as a dengue infection. The patient had mild thrombocytopenia and positive dengue IgG and IgM whereas the clinicians were not aware of the possibility of false-positive dengue serology revealed in the published case report from Singapore. The nurse put on a pair of gloves but did not wear a mask during the only encounter with this patient. This nosocomial transmission raised a safety concern among healthcare professionals in an area with a relatively low Covid-19 prevalence, especially when the clinical and laboratory characteristics could be confused with other viral infections.

Clinical Characteristics of Patients Hospitalized with Coronavirus Disease, Thailand.

Among 11 patients in Thailand infected with severe acute respiratory syndrome coronavirus 2, we detected viral RNA in upper respiratory specimens a median of 14 days after illness onset and 9 days after fever resolution. We identified viral co-infections and an asymptomatic person with detectable virus RNA in serial tests. We describe implications for surveillance.