Immunogenicity during 6 months after SARS-CoV-2 infection is significantly different depending on previous COVID-19 vaccine regimens and a booster dose received.

Data on immunogenicity induced by SARS-CoV-2 infection and its sustainability are essential to inform COVID-19 vaccine schedule. A prospective cohort study was conducted among adults at-risk for COVID-19 during the Omicron variant-dominant epidemic. All were followed up for anti-spike RBD levels on days 0, 14, 90 and 180 after enrollment. Of the 871 individuals included, 264 (30.3 %) had COVID-19. Those with COVID-19 had significantly lower baseline geometric mean level of anti-spike RBD than those without COVID-19 (326 vs. 989; P < 0.001). Among the COVID-19 patients, anti-spike RBD level significantly increased the most at 14 days after infection and dropped significantly at day 90 and day 180. Giving a booster dose during 91-180 days after infection induced high level of anti-spike RBD through 180 days. These findings suggest high level but short-lived immunity induced by SARS-CoV-2 infection while sustained immunity required a booster dose administered from 90 days after the infection.

Characterization of antibody response to SARS-CoV-2 Orf8 from three waves of COVID-19 outbreak in Thailand.

A dynamic of virus adaptation and a mass vaccination campaign could significantly reduce the severity of clinical manifestations of COVID-19 and transmission. Hence, COVID-19 may become an endemic disease globally. Moreover, mass infection as the COVID-19 pandemic progressed affected the serology of the patients as a result of virus mutation and vaccination. Therefore, a need exists to acquire accurate serological testing to monitor the emergence of new outbreaks of COVID-19 to promptly prevent and control the disease spreading. In this study, the anti-Orf8 antibodies among samples collected in Thailand's first, fourth, and fifth waves of COVID-19 outbreaks compared with pre-epidemic sera were determined by indirect ELISA. The diagnostic sensitivity and specificity of the anti-Orf8 IgG ELISA for COVID-19 samples from the first, fourth, and fifth waves of outbreaks was found to be 100% compared with pre-epidemic sera. However, the diagnostic sensitivity and specificity of the anti-Orf8 IgG ELISA for a larger number of patient samples and controls from the fifth wave of outbreaks which were collected on day 7 and 14 after an RT-PCR positive result were 58.79 and 58.44% and 89.19 and 58.44%, respectively. Our data indicated that some of the controls might have antibodies from natural past infections. Our study highlighted the potential utility of anti-Orf8 IgG antibody testing for seroprevalence surveys but still warrants further investigations.

Inhibitory effect of Zingiber cassumunar Roxb. (Phlai) on nasal cytokine productions and eosinophilic recruitment in patients with allergic rhinitis.

BACKGROUND: Zingiber cassumunar Roxb. (Phlai) has been used for the treatment of allergies including allergic rhinitis (AR). Although the anti-histamine effects have been reported, assessment of nasal cytokine and eosinophil production had not been investigated. OBJECTIVE: This study aimed to examine the effect of Phlai on alterations in nasal pro-inflammatory cytokine levels and eosinophil counts in nasal mucosa. METHODS: This was a randomized, double-blind, three-way crossover study. Nasal concentrations of cytokines, namely interleukin (IL)-4, IL-5, IL-13 and interferron-gamma (IFN-γ), nasal smear eosinophilia as well as total nasal symptom score (TNSS) were evaluated before and after a 4 weeks treatment with 200 mg Phlai capsules or placebo in 30 AR patients. RESULTS: We observed significant (p < 0.05) reduction in IL-5, IL-13 as well as the number of eosinophils in subjects given Phlai. The degree of improvement of TNSS after Phlai treatment was initially manifested in week 2 with the greatest effect in week 4. In contrast, there were no significant differences in all nasal cytokines, eosinophil counts or TNSS between before and after receiving placebo. CONCLUSIONS: These findings provided the first evidence for the anti-allergic effect of Phlai which possibly involved inhibition of nasal pro-inflammatory cytokines production and eosinophilic recruitment. Phlai thus represents a promising herbal medicine for alleviating inflammation and AR symptoms.

Attention-deficit/hyperactive-impulsive disorder symptoms among grade 1 students with reading disorder in Thailand.

BACKGROUND: Reading disorder is the most common comorbid condition with attention-deficit/hyperactive-impulsive disorder (ADHD) in school-aged children. PURPOSE: This study compared symptoms of ADHD among children in grade 1 at risk of reading disorder with children not at risk. METHODS: This cross-sectional study included 703 students in grade 1 aged 6-8 years from 8 schools in Pathumthani Province, Thailand, in 2019. Reading disorder was assessed using tools developed by Vibulpatanavong and Evans for Thai teachers, whereas the Thai parent and teacher versions of the Swanson, Nolan, and Pelham IV Rating Scale (SNAP-IV) was used to evaluate ADHD symptoms. Demographic data were collected from parents using a self-reported questionnaire. RESULTS: Among the 703 students with almost equal number of male (n=350) and female (n=353), and the average age of 6.56±0.57 years, 95 (13.51%) were classified (significantly male) at risk of reading disorder. The mean SNAP-IV scores of children with reading disorder reported by parents and teachers (20.23±10.95 and 20.75±15.08, respectively) were significantly higher than those of neurotypical children (16.04 ±8.59 and 9.00±10.14, respectively, P<0.05). Of the 95 students with reading disorder reported by parents and teachers, 29 (30.53%) and 20 (21.05%) respectively, were defined as having ADHD according to the standard cutoff SNAP-IV scores, which were significantly higher than 608 neurotypical students at 108 (17.76%) and 20 (5.59%) (P<0.05). The odds ratios of children with reading disorder having ADHD symptoms according to teacher reports were 3.32 (95% confidence interval [CI], 1.14-9.67; P<0.05), 3.75 (95% CI, 1.60-8.79; P<0.05), and 4.41 (95% CI, 1.20-16.15; P<0.05) for inattentive, hyperactive, and combined presentations, respectively. CONCLUSION: Grade 1 students with reading disorder had a significantly higher prevalence of ADHD symptoms than neurotypical students. Therefore, children with reading disorders should undergo ADHD assessments and receive proactive intervention.

Prevalence and associating factors of long COVID in pediatric patients during the Delta and the Omicron variants.

Introduction: The number of pediatric COVID-19 infections is increasing; however, the data on long COVID conditions in children is still limited. Our study aimed to find the prevalence of long COVID in children during the Delta and Omicron waves, as well as associated factors. Methods: A single-center prospective cohort study was conducted. We included 802 RT-PCR-confirmed COVID-19 pediatric patients in the Delta and Omicron periods. Long COVID was defined as having symptoms for ≥3 months after infection. Parents and/or patients were interviewed by phone. Multivariable logistic regression was performed to find associated factors with long COVID. Results: The overall prevalence of long COVID was 30.2%. The Delta period had more prevalence than the Omicron (36.3% vs. 23.9%). Common symptoms for patients 0-3 years' old were loss of appetite, rhinorrhea, and nasal congestion. Conversely, patients 3-18 years' old had hair loss, dyspnea on exertion, rhinorrhea, and nasal congestion. However, there was no significant negative impact on daily life. Most symptoms improved after a 6-month follow-up. Factors associated with long COVID-19 conditions were infection during the Omicron period (adjusted OR: 0.54; 95% CI: 0.39-0.74, P < 0.001), fever (adjusted OR: 1.49, 95% CI: 1.01-2.20, P = 0.04) and rhinorrhea (adjusted OR: 1.47, 95% CI: 1.06-2.02, P = 0.02). Conclusion: Infection during the Omicron wave has a lower prevalence of long COVID. The prognosis is often favorable, and most symptoms gradually become less. However, pediatricians may schedule appointments to surveil long COVID in children with fever or rhinorrhea as an initial symptom.

Prevalence, risk factors, and vaccine effectiveness of COVID-19 infection in thai children, adolescents, and young adults in the omicron era.

Background and objectives: The study of prevalence, risk factors, and vaccine effectiveness (VE) in children, adolescents, and young adults during the Omicron era has been limited, making this the objectives of the study. Methods: A prospective, test-negative case-control study was conducted on patients aged 0-24 years old classified as patients under investigation (PUI) from January to May 2022. PUI with positive RT-PCR within 14 days were classified as cases, whilst PUI with negative RT-PCR in 14 days were controls. Univariate and multivariate analyses determined risk factors; VE was calculated using [1-adjusted odds ratio (OR)] × 100. Results: The final analyses included 3,490 patients with a PUI infection rate of 45.6%. Heterologous vaccination regimens, including inactivated vaccines, viral vectors, and mRNA were utilized during the study period. A total of 2,563 patients (73.5%) had received at least 2 vaccine doses, regardless of regimen. Male gender and household infections were independent risk factors for the development of infection, with an adjusted OR of 1.55 and 1.45, respectively. Underlying comorbidities and obesity were not significantly associated with the development of infection. Patients with underlying comorbidities were more likely to have at least moderate severity of infection with the adjusted OR of 3.07. Age older than 11 years was associated with lower infection risk and development of at least moderate infection with adjusted OR of 0.4 and 0.34, respectively. Vaccinated participants also had a lower risk of developing at least moderate infection: adjusted OR of 0.40. The adjusted VE of any vaccination regimen for infection prevention for one, two, three, or more than four doses was 21.8%, 30.6%, 53.5%, and 81.2%, respectively. The adjusted VE of any vaccination regimen for prevention of at least moderate severity of the disease for one, two, three, or more than four doses was 5.7%, 24.3% 62.9%, and 90.6%, respectively. Conclusion: Disease prevalence among PUI was substantially high during the Omicron wave. A two-dose vaccination regimen does not appear sufficient to ensure protection against infection.

Diagnostic accuracy of atopy patch test in children with cow's milk allergy.

BACKGROUND: The accuracy of an atopy patch test (APT) for fresh cow's milk allergy is controversial. Few studies have focused on commercial extract solutions. We aimed to evaluate the diagnostic performance of the APT in cow's milk allergic children using fresh cow's milk and commercial extracts of cow's milk and its components including casein, α-lactalbumin, and ß-lactoglobulin. METHODS: A prospective study was carried out in children with a history of cow's milk allergy. Children underwent the skin prick test (SPT) and APT with fresh cow's milk, powdered cow's milk, and commercial extracts of cow's milk, casein, α-lactalbumin, and ß-lactoglobulin. Oral food challenge (OFC) was confirmed in all children. RESULTS: A total of 37 patients participated (mean age 13.14 ± 7.26 months). Only 5 (13.51%) patients had positive OFC to cow's milk. The sensitivity of the APT using fresh cow's milk was 40%, specificity was 65.6%, PPV was 15.4%, and NPV was 87.5%. The sensitivity of the APT using powdered cow's milk was 40%, 60.7% for specificity, 15.4% for PPV, and 58% for NPV. The sensitivity and PPV of the APT using commercial solutions of cow's milk, casein, α-lactalbumin, and ß-lactoglobulin were zero. The specificities were 90.6%, 93.8%, 100%, and 100% for α-lactalbumin, cow's milk, casein, and ß-lactoglobulin, respectively. CONCLUSIONS: APT using commercial solutions showed higher specificity than fresh milk. The specificity increased using a protein component allergen.

Real-life effectiveness of COVID-19 vaccine during the Omicron variant-dominant pandemic: how many booster doses do we need?

The surge in coronavirus disease 2019 (COVID-19) caused by the Omicron variants of the severe acute respiratory syndrome coronavirus 2 necessitates researches to inform vaccine effectiveness (VE) and other preventive measures to halt the pandemic. A test-negative case-control study was conducted among adults (age ≥18 years) who were at-risk for COVID-19 and presented for nasopharyngeal real-time polymerase chain reaction testing during the Omicron variant-dominant period in Thailand (1 January 2022-15 June 2022). All participants were prospectively followed up for COVID-19 development for 14 days after the enrolment. Vaccine effectiveness was estimated and adjusted for characteristics associated with COVID-19. Of the 7971 included individuals, there were 3104 cases and 4867 controls. The adjusted VE among persons receiving 2-dose, 3-dose, and 4-dose vaccine regimens for preventing infection and preventing moderate-to-critical diseases were 33%, 48%, 62% and 60%, 74%, 76%, respectively. The VE were generally higher among those receiving the last dose of vaccine within 90 days compared to those receiving the last dose more than 90 days prior to the enrolment. The highest VE were observed in individuals receiving the 4-dose regimen, CoronaVac-CoronaVac-ChAdOx1 nCoV-19-BNT162b2 for both preventing infection (65%) and preventing moderate-to-critical diseases (82%). Our study demonstrated increased VE along with an increase in number of vaccine doses received. Current vaccination programmes should focus on reducing COVID-19 severity and mandate at least one booster dose. The heterologous boosters with viral vector and mRNA vaccines were highly effective and can be used in individuals who previously received the primary series of inactivated vaccine.

Outcomes of young children hospitalized with acute wheezing.

BACKGROUND: Wheezing in preschool children is a common symptom. OBJECTIVE: The study aimed to determine an incidence of recurrent wheezing among young children who had been hospitalized with acute wheezing after 12 months. Factors associated with recurrent wheezing were explored. METHODS: A longitudinal study was conducted among 236 children, aged between 6 months and 5 years, who were hospitalized with acute wheezing in 4 hospitals located in Bangkok and adjacent provinces, Thailand. Demographics, house environments and clinical characteristic data were collected at entry. Serum specific IgE levels against common food and inhalant allergens and serum 25-hydroxyvitamin D (25OHD) concentrations were measured. RESULTS: At entry, the mean age was 24.4 months (SD = 15.7 months). Of 236 hospitalized children with acute wheezing, ninety-four cases (39.8%) were the first wheezing episode of life. By laboratory results, 197 (83.5%) and 56 (23.7%) children were atopic and had vitamin D insufficiency respectively. There were 195 cases completely followed for 12 months. One-year risk of emergency visits and hospitalization due to recurrent wheezing were 49.7% and 23.1% respectively. By multivariable analysis, being the second born child or more, vitamin D insufficiency, "ever wheeze", and allergic rhinitis were significantly associated with recurrent wheezing within 12 months with adjusted odds ratios of 2.5 (95% confidence interval: 1.3-5.3), 2.3 (95% confidence interval: 1.1-4.4), 1.9 (95% confidence interval: 1.2-3.5), and 1.6 (95% confidence interval: 1.3-2.9) respectively. CONCLUSIONS: Being the second born child or more, vitamin D insufficiency, ever wheeze, and allergic rhinitis were significant risks of recurrent wheezing.

Efficacy, patients' perception, and cost of medication in allergic rhinitis with subcutaneous immunotherapy.

BACKGROUND: Allergic rhinitis (AR) is the allergic inflammation of nasal mucosa. Treatment of AR includes pharmacotherapy and allergen immunotherapy. Subcutaneous immunotherapy (SCIT) is indicated in inadequate disease control, patient's preference, or impossible allergen avoidance. SCIT is an effective treatment but its cost is comparatively high. Efficacy, patient perception, and cost of medication are rarely explored in Asia. OBJECTIVE: To study efficacy, patient perception, and cost-benefit of SCIT in AR. METHODS: We performed a descriptive cross-sectional study at Thammasat University Hospital, Thailand. AR patients who had been receiving SCIT were interview. Current and recall of AR total symptom score (TSS), quality of life, and perception were scored. Cost of medications before SCIT and current cost were reviewed from the medical records. RESULTS: A total of 142 patients were enrolled. Sixty-eight patients (47.9%) received single allergen; house dust mite was the most common allergen. The median of maintenance phase was 47 months, range 15-142 months. The mean of current TSS was significantly lower than mean TSS before SCIT. Forty-two patients (29.6%) had discontinued SCIT on the day of the interview. After discontinuation of SCIT, TSS was still lower than TSS before SCIT. The average cost of medications including SCIT was lower than that of before SCIT with an average difference of 254.2 USD/year. Sixteen patients (11.3%) experienced systemic reaction, 8 of which had reaction during rush immunotherapy. CONCLUSIONS: SCIT is an effective, cost-saving and safe treatment option for AR. Rush immunotherapy can reduce duration of build-up phase but increase the risk of systemic reaction.

Minimum number and types of allergens for a skin prick test panel in Thai children with allergic respiratory diseases.

BACKGROUND: Patterns of aeroallergen sensitization vary by countries. Testing with the minimum number of allergens is important to identify sensitized patients for a cost-effective approach. We aimed to assess the minimal skin prick test (SPT) panel to identify sensitized children with allergic respiratory diseases. METHODS: The SPT results from January 2020 to December 2021 in children aged 2-18 years with symptoms of asthma or allergic rhinitis or both were retrospectively reviewed. All children received 11 allergen extracts (Dermatophagoides pteronyssinus [Der p], Dermatophagoides farinae [Der f], American cockroach, German cockroach, cat, dog, Bermuda grass, careless weed, Timothy, Acacia, and molds). The conditional approach was used to determine the allergen selection for the SPT panel. RESULTS: A total of 688 children were enrolled (mean age = 8.14 ± 3.91 years). The sensitization results were Der p (57.85%), Der f (55.09%), German cockroach (18.02%), American cockroach (17.01%), cat (11.77%), Acacia (3.49%), Bermuda grass (3.34%), molds (3.05%), Timothy (2.33%), dog (1.89%), and careless weed (1.60%). Der p, Der f, and German cockroach were required to detect at least 95% of sensitized children. If the SPT panel added Acacia, cat, American cockroach, Bermuda grass, and careless weed, sensitization was detected in 99-100% of cases. CONCLUSIONS: Indoor allergens (Der p, cockroach, and cat) were common causes of sensitization in Thai children with allergic respiratory diseases. Eight allergens were sufficient for sensitization identification in Thai children with asthma or allergic rhinitis or both in clinical practice.

Development and validation of the predictive score for pediatric COVID-19 pneumonia: A nationwide, multicenter study.

BACKGROUND: Due to the possibility of asymptomatic pneumonia in children with COVID-19 leading to overexposure to radiation and problems in limited-resource settings, we conducted a nationwide, multi-center study to determine the risk factors of pneumonia in children with COVID-19 in order to create a pediatric pneumonia predictive score, with score validation. METHODS: This was a retrospective cohort study done by chart review of all children aged 0-15 years admitted to 13 medical centers across Thailand during the study period. Univariate and multivariate analyses as well as backward and forward stepwise logistic regression were used to generate a final prediction model of the pneumonia score. Data during the pre-Delta era was used to create a prediction model whilst data from the Delta one was used as a validation cohort. RESULTS: The score development cohort consisted of 1,076 patients in the pre-Delta era, and the validation cohort included 2,856 patients in the Delta one. Four predictors remained after backward and forward stepwise logistic regression: age < 5 years, number of comorbidities, fever, and dyspnea symptoms. The predictive ability of the novel pneumonia score was acceptable with the area under the receiver operating characteristics curve of 0.677 and a well-calibrated goodness-of-fit test (p = 0.098). The positive likelihood ratio for pneumonia was 0.544 (95% confidence interval (CI): 0.491-0.602) in the low-risk category, 1.563 (95% CI: 1.454-1.679) in the moderate, and 4.339 (95% CI: 2.527-7.449) in the high-risk. CONCLUSION: This study created an acceptable clinical prediction model which can aid clinicians in performing an appropriate triage for children with COVID-19.

Epidemiological and Clinical Characteristics of Pediatric COVID-19 in the Tertiary Care System in Thailand: Comparative Delta and pre-Delta Era.

Background: Few studies had focused on the epidemiological and clinical characteristics of pediatric COVID-19 (SARS-CoV-2) during Delta and pre-Delta eras in Asia, despite it being a pandemic. Objective: To study the epidemiological and clinical characteristics of three waves of pediatric COVID-19 infections in a tertiary-care setting in Thailand. Methods: This retrospective study reviewed all PCR-confirmed pediatric (0-18 years of age) COVID-19 infections between January 13, 2020, and October 31, 2021, in a tertiary care system in Thailand. Results: 1,019 patients, aged 0.02 - 18 years, 552 (54.2%) male, and 467 (45.8%) female, with a median age of 9.2 years, were enrolled. Asymptomatic cases accounted for 35.7%, of which 106 (18.9%) had abnormal chest X-ray findings. Most cases were classified as having mild clinical symptoms, with only 8 (0.8%) and 4 (0.4%) developing a severe and critical illness, respectively. There were no deaths. The Delta variant appeared more transmissible than previous ones, but we did not see any difference in disease severity. Upper respiratory tract symptoms were predominant, while few cases had lower respiratory tract involvement. The sensitivity and specificity of dyspnea symptoms to predict radiologically confirmed pneumonia were 14% and 95%, respectively, with a likelihood ratio of 3.37. The overall prognosis was good, with only 13 (1.3 %) needing respiratory support. All cases showed clinical improvement with a decent recovery. Conclusion: Pediatric COVID-19 during the Delta variant predominance era generally appeared more transmissible but benign. One-fifth of cases had pneumonia, but few cases needed respiratory support. Prevention remains important for disease control.

A randomized controlled study comparing the efficacy of soap versus soap-plus-microwave disinfection for irrigation device in children with acute rhinosinusitis.

BACKGROUND: Nasal irrigation is an effective component of sino-nasal disease management. Nonetheless, bacterial contamination is worrisome. OBJECTIVE: To study bacterial colonization incidence using squeeze-bottle nasal irrigation devices, after disinfection with soap or soap-plus-microwave technique, in pediatric acute rhinosinusitis. METHODS: A randomized, prospective, controlled study was conducted on acute rhinosinusitis children, aged 2-15 years. Each participant was randomized into a soap-cleaning or soap-plus- microwave group. For a two-week period, participants irrigated their nostrils with NSS twice daily and cleaned the bottle after each use. In the end, bottles were sent to a microbiological laboratory for bacterial identification. RESULTS: The mean 5S Score and satisfaction score gradually improved in both groups with no significant differences between groups. Bacterial identification frequency in the soap group was slightly higher than in the soap-plus-microwave one, without statistical significance. For safety and tolerability, all participants reported 100% adherence to nasal irrigation. The soap-plus-microwave group reported more minor adverse outcomes than the soap-cleaning one. No thermal deformation of irrigation bottles was observed. CONCLUSIONS: Regular cleaning of nasal irrigation devices is needed to minimize bacterial contamination. Only soap or soap plus microwave disinfection appeared simple and safe for disinfection. Both techniques can equally minimize the rate of bacterial contamination. Although no gross thermal deformation at optimal power and duration, chemical irritants after high power or long microwave durations may be a concern.

An epidemiological study of pediatric COVID-19 in the era of the variant of concern.

BACKGROUND: There were limited epidemiological data of pediatric COVID-19 in Asia outside China, especially during the era of the variants of concern such as the Delta and Alpha variants. The objective was to describe the clinical epidemiology of pediatric COVID-19 in a tertiary care center in Thailand from April to August 2021. The identification of risk factors for the development of pneumonia in these children was also performed. METHODS: This retrospective cohort study was conducted by retrospective chart review of all children aged 0-15 years admitted to Thammasat University Hospital care system during the study period. The risk factors for the development of pneumonia were analyzed using logistic regression. RESULTS: A total of 698 children were included for analysis, of which 52% were male. The mean age of the cohort was 7.2 + 4.5 years old. Radiographic pneumonia was identified in 100 children (14.3%) and a total of 16 children (2.3%) were diagnosed with severe and critical diseases. The mortality rate was 0.1%. Children younger than 1 year and children with comorbidity were at higher risk of developing pneumonia (Adjusted odds ratios 2.99 (95% confidence interval (CI): 1.56-5.74) and 2.32 (95% CI: 1.15-4.67), respectively). CONCLUSION: In the era of the variants of concern, the proportion of children with severe and critical diseases remained low. However, prudence must be taken in caring for younger children and children with comorbidity.

Comparing real-life effectiveness of various COVID-19 vaccine regimens during the delta variant-dominant pandemic: a test-negative case-control study.

Data on real-life vaccine effectiveness (VE), against the delta variant (B.1.617.2) of the severe acute respiratory syndrome coronavirus 2 among various coronavirus disease 2019 (COVID-19) vaccine regimens are urgently needed to impede the COVID-19 pandemic. We conducted a test-negative case-control study to assess the VE of various vaccine regimens for preventing COVID-19 during the period when the delta variant was the dominant causative virus (≥ 95%) in Thailand (25 July 2021-23 Oct 2021). All individuals (age ≥18 years) at-risk for COVID-19, presented for nasopharyngeal real-time polymerase chain reaction (RT-PCR) testing, were prospectively enrolled and followed up for disease development. Vaccine effectiveness was estimated with adjustment for individual demographic and clinical characteristics. Of 3353 included individuals, there were 1118 cases and 2235 controls. The adjusted VE among persons receiving two-dose CoronaVac plus one BNT162b2 booster was highest (98%; 95% confidence interval [CI] 87-100), followed by those receiving two-dose CoronaVac plus one ChAdOx1 nCoV-19 booster (86%; 95% CI 74-93), two-dose ChAdOx1 nCoV-19 (83%; 95% CI 70-90), one CoronaVac dose and one ChAdOx1 nCoV-19 dose (74%; 95% CI 43-88) and two-dose CoronaVac (60%; 95% CI 49-69). One dose of CoronaVac or ChAdOx1 nCoV-19 had a VE of less than 50%. Our study demonstrated the incremental VE with the increase in the number of vaccine doses received. The two-dose CoronaVac plus one BNT162b2 or ChAdOx1 nCoV-19 booster regimens was highly effective in preventing COVID-19 during the rise of delta variant.

Concordance of skin test reactivity between indoor inhalant allergens among children with allergic respiratory disease.

BACKGROUND: In vitro studies have demonstrated cross-reactivity among indoor allergen proteins in children with allergic respiratory diseases. However, there are only few studies evaluating in vivo response. A skin prick test (SPT) with commercial indoor solutions is widely used in clinical practice. We aimed to evaluate SPT agreement in children with allergic respiratory disease between pairs of common indoor allergens. METHODS: We reviewed SPT results of children 2 to 18 years old, diagnosed with respiratory allergic disease. Results from house dust mite (Dermatophagoides farinae, Dermatophagoides pteronyssinus), cockroach (Periplaneta americana, Blatella germanica), cat and dog were collected. Sensitization was defined as ≥ 3 mm in wheal diameter. Kappa coefficient (κ) was used to analyze sensitization concordance for each allergen pair. RESULTS: The charts of 300 children, 187 (62.33%) males, were reviewed. Mean age was 7.43 ± 3.29 years with 183 (61%), 140 (46.67%), 45 (15%), 30 (10%) sensitizations to house dust mite (HDM), cockroach, cat and dog, respectively. Sensitization concordance between HDM and cockroach was moderate: κ = 0.53 (95% CI: 0.42-0.64). Moderate agreement occurred between dog and cat: κ = 0.41 (95%CI: 0.30-0.52). HDM-sensitized children showed poor concordance with both cat κ = 0.17 (95%CI: 0.09-0.24) and dog κ = 0.09 (95%CI: 0.03-0.14). There was also poor concordance between cockroach-sensitized children to cat κ = 0.19 (95%CI; 0.11-0.28) and dog κ = 0.11 (95%CI; 0.04-0.18). CONCLUSION: We demonstrated moderate agreement of SPT response between HDM and cockroach as well as dog and cat. This may be due to cross-reactivity. Component-resolved diagnosis should be considered in children with co-sensitization of these allergen pairs.

Associations between the infant and young child feeding index and nutritional status.

BACKGROUND: The infant and child feeding index (ICFI) is a single summary World Health Organization influenced index to assess feeding quality in infants and young children aged 6-36 months. This study aimed to demonstrate any associations between ICFI and nutritional status in a single Thai center. METHODS: The demographic data and feeding practices of healthy infants and children aged 6-36 months were collected from questionnaires given to 304 parents/caregivers; anthropometric measurements were taken. Associations between ICFI and weight-for-age Z scores (WAZ), length/height for age Z scores (LAZ/HAZ), weight-for-length/height Z scores (WLZ/WHZ), and body mass index-for-age Z scores (BAZ) were examined. RESULTS: The mean ICFI was 6.14 ± 1.63 and was lowest in the 6-8 months age group. Breastfed infants had significantly higher ICFI scores than those not breastfed. Factors influencing ICFI were infant age and milk volume intake. The ICFI was negatively associated with WAZ, WLZ/WHZ, and BAZ (ß = -0.13, P = 0.037; ß = -0.17, p = 0.01; ß = -0.15, P = 0.026, respectively). Breastfeeding was also negatively associated with WAZ, LAZ/HAZ, WLZ/WHZ, and BAZ. CONCLUSIONS: This study demonstrated a negative association between the ICFI and nutritional status. Breastfeeding may have obscured some positive effects from appropriate feeding practices, while dairy consumption may have hidden negative outcome from inappropriate ones. Despite the ICFI appearing to reflect infant and young child feeding behaviors, using the ICFI alone may not accurately reveal nutritional status.

Predictors of severe adverse outcomes in febrile neutropenia of pediatric oncology patients at a single institute in Thailand.

Febrile neutropenia in pediatric oncology patients may lead to severe infection, with adverse events including septic shock or death. The aim of the study was to investigate the prevalence of severe adverse outcomes and to determine the associated risk factors. This is a retrospective cohort study of pediatric oncology patients with febrile neutropenia from October 2013 to September 2017 at Thammasat University Hospital, Thailand. Clinical assessment and time-to-event of severe outcomes were analyzed. There were 95 febrile neutropenic episodes; severe adverse outcomes were documented in 11 (11.5%), with no infection-associated mortalities. Those with severe outcomes were older, received prophylactic granulocyte-colony stimulating factor (G-CSF), and had documented infection, lower initial ANC, and central venous catheter insertion. The proportional hazard regression model revealed age ≥ 10 years (hazard ratio [HR], 5.96; p = 0.005), prophylactic G-CSF (HR, 4.52; p = 0.028), and microbiologically documented infections (HR, 12.53; p = 0.017) independently predicted severe adverse outcomes. Although severe adverse outcomes occurred in only 11.5% of our febrile neutropenic episodes, we identified a few risk factors that may help predict those at highest risk.

Prevalence and risk factors of allergic rhinitis in children in Bangkok area.

BACKGROUND: Allergic rhinitis (AR) is a disease with a high global disease burden and significant morbidity and expense. Risk factors are not well understood. OBJECTIVE: The objective of our project is to study the prevalence and risk factors of AR in children living in the Bangkok area. METHODS: A cross-sectional, multi-center survey using new GAN core questionnaires on current AR and risk factors was completed by 3,074 parents of children aged 6-7 years and by 3,217 children aged 13-14 years, directly. RESULTS: The prevalence of current AR in children aged 6-7 years and 13-14 years was 15.0% (95% confidence interval [CI]:13.8-16.3%) and 17.5% (95% CI: 16.2-18.8%), respectively. The prevalence of severe AR in children aged 6-7 years and 13-14 years was 1.0% (95% CI: 0.6-1.3%) and 1.9% (95% CI: 1.4-2.4%), respectively. Co-morbidity with asthma and eczema was 27.1% and 24.6%, respectively. Significant factors associated with AR include parental history of asthma (p = 0.025), parental history of AR (p < 0.001), parental history of eczema (p < 0.001), lower respiratory tract infection in the first year of life (p < 0.001), breastfeeding (p = 0.019), current use of paracetamol (p < 0.001), exercise (p < 0.001), current cat exposure (p = 0.008), and truck traffic on the street of residence (< 0.001). CONCLUSION: AR is a common disease among children residing in Bangkok. This study confirms that a family history of atopy (asthma, AR, and eczema), antibiotics given in the first year of life, current paracetamol use, exercise, current cat exposure, and truck traffic on the street of residence are important and significant risk factors for AR symptoms.