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1.
Mycology ; 15(1): 70-84, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558844

RESUMO

In India, the incidence of mucormycosis reached high levels during 2021-2022, coinciding with the COVID-19 pandemic. In response to this, we established a multicentric ambispective cohort of patients hospitalised with mucormycosis across India. In this paper, we report their baseline profile, clinical characteristics and outcomes at discharge. Patients hospitalized for mucormycosis during March-July 2021 were included. Mucormycosis was diagnosed based on mycological confirmation on direct microscopy (KOH/Calcofluor white stain), culture, histopathology, or supportive evidence from endoscopy or imaging. After consent, trained data collectors used medical records and telephonic interviews to capture data in a pre-tested structured questionnaire. At baseline, we recruited 686 patients from 26 study hospitals, of whom 72.3% were males, 78% had a prior history of diabetes, 53.2% had a history of corticosteroid treatment, and 80% were associated with COVID-19. Pain, numbness or swelling of the face were the commonest symptoms (73.3%). Liposomal Amphotericin B was the commonest drug formulation used (67.1%), and endoscopic sinus surgery was the most common surgical procedure (73.6%). At discharge, the disease was stable in 43.3%, in regression for 29.9% but 9.6% died during hospitalization. Among survivors, commonly reported disabilities included facial disfigurement (18.4%) and difficulties in chewing/swallowing (17.8%). Though the risk of mortality was only 1 in 10, the disability due to the disease was very high. This cohort study could enhance our understanding of the disease's clinical progression and help frame standard treatment guidelines.

2.
Epidemiol Infect ; 152: e56, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38497493

RESUMO

In the third week of September 2022, an outbreak of measles was reported from a slum in Eastern Mumbai, India. We sought to investigate whether failure to vaccinate or vaccine failure was the cause. We constructed an epidemic curve, drew a spot map, and calculated the attack rate and case-fatality ratio. We calculated vaccine effectiveness (VE) for one and two doses of measles vaccine in an unmatched case-control study and did stratified analysis by sex, availability of vaccination card, and migrant status. We identified 358 cases and four deaths with a 11.3% attack rate and 1.1% case fatality, both being highest among 0-24-month-old boys. The epidemic curve suggested a propagated mode of spread. The VE for two doses was 64% (95% confidence interval (CI): 23-73%) among under-5-year-old children and 70% (95% CI: 28-88%) among 5-15-year-old children. Failure to vaccinate, consequent to the COVID-19 pandemic, and vaccine hesitancy might have led to the accumulation of susceptible children in the community. Additionally, the occurrence of case-patients among vaccinated suggests reduced VE, which needs further investigation into humoral and cell-mediated immunity as well as contributory factors including nutritional status. Outbreak response immunization to complete immunization of missed and dropout children was carried out to control the outbreak.


Assuntos
Sarampo , Áreas de Pobreza , Masculino , Humanos , Lactente , Pré-Escolar , Recém-Nascido , Estudos de Casos e Controles , Pandemias , Sarampo/epidemiologia , Sarampo/prevenção & controle , Vacina contra Sarampo , Surtos de Doenças/prevenção & controle , Vacinação , Índia/epidemiologia
5.
Cureus ; 15(10): e47892, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38034216

RESUMO

Background Implant-supported fixed dental prostheses (FDPs) have become a reliable method for the rehabilitation of edentulous patients, offering improved contour, function, esthetics, and overall oral health. This retrospective study aimed to evaluate the impact of implant angulation on the stress distribution and survival rate of implant-supported FDPs using finite element analysis (FEA). Methods A retrospective cross-sectional design was employed, utilizing existing patient records and radiographic data. The study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines for transparent and comprehensive reporting. Sample size calculation was based on a reference study, considering a standard deviation of 2.5 for stress distribution measurements and a minimum detectable effect size of 1.0. Data collection included demographic and clinical characteristics, implant selection and placement details, prosthetic design and fabrication, as well as stress distribution analysis using FEA. Results The study included a total of 307 participants who met the inclusion criteria. Demographic variables demonstrated a balanced gender distribution (p = 0.172), with 51.5% males and 48.5% females. Smoking status (p < 0.001) and income level (p = 0.026) were significantly associated with the research outcomes. Implant characteristics analysis revealed three main types: NobelReplace Select (53.6%), Straumann Bone Level (31.9%), and BioHorizons Tapered Internal (14.5%). Implant type (p < 0.001), length (p = 0.003), diameter (p = 0.019), and manufacturer (p < 0.001) were all found to have statistically significant associations with the research outcomes. Conclusion The findings of this retrospective study highlight the importance of implant angulation on the stress distribution and survival rate of implant-supported FDPs. The evaluation of stress distribution patterns and the analysis of implant characteristics provide valuable insights for optimizing implant design and placement strategies.

6.
Indian J Med Res ; 158(4): 351-362, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37988028

RESUMO

BACKGROUND OBJECTIVES: In view of anecdotal reports of sudden unexplained deaths in India's apparently healthy young adults, linking to coronavirus disease 2019 (COVID-19) infection or vaccination, we determined the factors associated with such deaths in individuals aged 18-45 years through a multicentric matched case-control study. METHODS: This study was conducted through participation of 47 tertiary care hospitals across India. Cases were apparently healthy individuals aged 18-45 years without any known co-morbidity, who suddenly (<24 h of hospitalization or seen apparently healthy 24 h before death) died of unexplained causes during 1 st October 2021-31 st March 2023. Four controls were included per case matched for age, gender and neighborhood. We interviewed/perused records to collect data on COVID-19 vaccination/infection and post-COVID-19 conditions, family history of sudden death, smoking, recreational drug use, alcohol frequency and binge drinking and vigorous-intensity physical activity two days before death/interviews. We developed regression models considering COVID-19 vaccination ≤42 days before outcome, any vaccine received anytime and vaccine doses to compute an adjusted matched odds ratio (aOR) with 95 per cent confidence interval (CI). RESULTS: Seven hundred twenty nine cases and 2916 controls were included in the analysis. Receipt of at least one dose of COVID-19 vaccine lowered the odds [aOR (95% CI)] for unexplained sudden death [0.58 (0.37, 0.92)], whereas past COVID-19 hospitalization [3.8 (1.36, 10.61)], family history of sudden death [2.53 (1.52, 4.21)], binge drinking 48 h before death/interview [5.29 (2.57, 10.89)], use of recreational drug/substance [2.92 (1.1, 7.71)] and performing vigorous-intensity physical activity 48 h before death/interview [3.7 (1.36, 10.05)] were positively associated. Two doses lowered the odds of unexplained sudden death [0.51 (0.28, 0.91)], whereas single dose did not. INTERPRETATION CONCLUSIONS: COVID-19 vaccination did not increase the risk of unexplained sudden death among young adults in India. Past COVID-19 hospitalization, family history of sudden death and certain lifestyle behaviors increased the likelihood of unexplained sudden death.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas , COVID-19 , Adulto Jovem , Humanos , Estudos de Casos e Controles , Vacinas contra COVID-19 , Consumo Excessivo de Bebidas Alcoólicas/complicações , Morte Súbita/etiologia , COVID-19/epidemiologia , COVID-19/complicações
7.
J Pharm Bioallied Sci ; 15(Suppl 2): S1332-S1334, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37694041

RESUMO

Due to the primary closure of the fragile tissues, large postoperative drainage is unexpected following a periodontal medical procedure. This case study elaborately illustrates the formation of a "liver coagulation" or "currant jam clot" following a periodontal fold surgical operation. Contamination, internal damage, and the presence of foreign particles such as bone splinters or bits of dental restorative dressing can all increase the risk of an incident happening.

8.
Indian J Med Res ; 158(2): 136-144, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37675689

RESUMO

Background & objectives: The post-acute effects of COVID-19 are continually being updated. This investigation was conducted to evaluate the determinants of post discharge mortality in hospitalized COVID-19 patients, especially 18-45 yr of age. Methods: A series of three nested case-control analyses was conducted on follow up data collected in the National Clinical Registry for COVID-19 between September 2020 and February 2023 from 31 hospitals. Matching (1:4) was done by the date of hospital admission ±14 days for the following comparisons: (i) case-patients reported as dead vs. controls alive at any contact within one year follow up; (ii) the same in the 18-45 yr age group and (iii) case-patients reported as dead between the first and one year of follow up vs. controls alive at one year post discharge. Results: The one year post discharge mortality was 6.5 per cent (n=942). Age [≤18 yr: adjusted odds ratio (aOR) (95% confidence interval [CI]): 1.7 (1.04, 2.9); 40-59 yr: aOR (95% CI): 2.6 (1.9, 3.6); ≥60 yr: aOR (95% CI): 4.2 (3.1, 5.7)], male gender [aOR (95% CI): 1.3 (1.1, 1.5)], moderate-to-severe COVID-19 [aOR (95% CI): 1.4 (1.2, 1.8)] and comorbidities [aOR (95%CI): 1.8 (1.4, 2.2)] were associated with higher odds of post-discharge one-year mortality, whereas 60 per cent protection was conferred by vaccination before the COVID-19 infection. The history of moderate-to-severe COVID-19 disease [aOR (95% CI): 2.3 (1.4, 3.8)] and any comorbidities [aOR (95% CI): 3 (1.9, 4.8)] were associated with post-discharge mortality in the 18-45-yr age bracket as well. Post COVID condition (PCC) was reported in 17.1 per cent of the participants. Death beyond the first follow up was associated with comorbidities [aOR (95%CI): 9.4 (3.4, 26.1)] and reported PCC [aOR (95% CI): 2.7 (1.2, 6)]. Interpretation & conclusions: Prior vaccination protects against post discharge mortality till one year in hospitalized COVID-19 patients. PCC may have long term deleterious effects, including mortality, for which further research is warranted.


Assuntos
COVID-19 , Humanos , Masculino , Alta do Paciente , Assistência ao Convalescente , Síndrome de COVID-19 Pós-Aguda , Hospitalização
9.
J Interferon Cytokine Res ; 43(10): 469-477, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37708007

RESUMO

Cytokines are major players in orchestrating inflammation, disease pathogenesis, and severity during COVID-19. Members of the interleukin (IL)-10 family of cytokines play important roles in regulating immune responses to various inflammatory and infectious diseases. However, the role of the IL-10 family of cytokines in COVID-19 remains elusive. Hence, we determined the plasma levels of the IL-10 family of cytokines (IL-10, IL-19, IL-20, IL-22, and IL-24) in 7 groups of COVID-19 individuals, based on days since real-time reverse transcriptase-polymerase chain reaction confirmation of SARS-CoV-2 infection. Our data show that the levels of IL-10, IL-19, IL-20, IL-22, and IL-24 cytokines decreased from days 15-30 to days 61-90 and plateaued thereafter. Severe COVID-19 patients exhibit increased plasma levels of IL-10, IL-19, IL-20, IL-22, and IL-24 compared to mild patients. Thus, our study provides evidence of alterations in the plasma levels of the IL-10 family of cytokines in convalescent COVID-19 individuals.

10.
Lancet Reg Health Southeast Asia ; 14: 100205, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37193348

RESUMO

Background: The COVID-19 pandemic showcased the power of genomic sequencing to tackle the emergence and spread of infectious diseases. However, metagenomic sequencing of total microbial RNAs in wastewater has the potential to assess multiple infectious diseases simultaneously and has yet to be explored. Methods: A retrospective RNA-Seq epidemiological survey of 140 untreated composite wastewater samples was performed across urban (n = 112) and rural (n = 28) areas of Nagpur, Central India. Composite wastewater samples were prepared by pooling 422 individual grab samples collected prospectively from sewer lines of urban municipality zones and open drains of rural areas from 3rd February to 3rd April 2021, during the second COVID-19 wave in India. Samples were pre-processed and total RNA was extracted prior to genomic sequencing. Findings: This is the first study that has utilised culture and/or probe-independent unbiased RNA-Seq to examine Indian wastewater samples. Our findings reveal the detection of zoonotic viruses including chikungunya, Jingmen tick and rabies viruses, which have not previously been reported in wastewater. SARS-CoV-2 was detectable in 83 locations (59%), with stark abundance variations observed between sampling sites. Hepatitis C virus was the most frequently detected infectious virus, identified in 113 locations and co-occurring 77 times with SARS-CoV-2; and both were more abundantly detected in rural areas than urban zones. Concurrent identification of segmented virus genomic fragments of influenza A virus, norovirus, and rotavirus was observed. Geographical differences were also observed for astrovirus, saffold virus, husavirus, and aichi virus that were more prevalent in urban samples, while the zoonotic viruses chikungunya and rabies, were more abundant in rural environments. Interpretation: RNA-Seq can effectively detect multiple infectious diseases simultaneously, facilitating geographical and epidemiological surveys of endemic viruses that could help direct healthcare interventions against emergent and pre-existent infectious diseases as well as cost-effectively and qualitatively characterising the health status of the population over time. Funding: UK Research and Innovation (UKRI) Global Challenges Research Fund (GCRF) grant number H54810, as supported by Research England.

11.
Glob Health Sci Pract ; 11(2)2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37116929

RESUMO

To reduce TB deaths in resource-limited settings, a differentiated care strategy can be used to triage patients with high risk of severe illness (i.e., those with very severe undernutrition, respiratory insufficiency, or inability to stand without support) at diagnosis and refer them for comprehensive assessment and inpatient care. Globally, there are few examples of implementing this type of strategy in routine program settings. Beginning in April 2022, the Indian state of Tamil Nadu implemented a differentiated care strategy called Tamil Nadu-Kasanoi Erappila Thittam (TN-KET) for all adults aged 15 years and older with drug-susceptible TB notified by public facilities. Before evaluating the impact on TB deaths, we sought to understand the retention and delays in the care cascade as well as predictors of losses. During April-June 2022, 14,961 TB patients were notified and 11,599 (78%) were triaged. Of those triaged, 1,509 (13%) were at high risk of severe illness; of these, 1,128 (75%) were comprehensively assessed at a nodal inpatient care facility. Of 993 confirmed as severely ill, 909 (92%) were admitted, with 8% unfavorable admission outcomes (4% deaths). Median admission duration was 4 days. From diagnosis, the median delay in triaging and admission of severely ill patients was 1 day each. Likelihood of triaging decreased for people with extrapulmonary TB, those diagnosed in high-notification districts or teaching hospitals, and those transferred out of district. Predictors of not being comprehensively assessed included: aged 25-34 years, able to stand without support, and diagnosis at a primary or secondary-level facility. Inability to stand without support was a predictor of unfavorable admission outcomes. To conclude, the first quarter of implementation suggests that TN-KET was feasible to implement but could be improved by addressing predictors of losses in the care cascade and increasing admission duration.


Assuntos
Desnutrição , Adulto , Humanos , Índia/epidemiologia
12.
Clin Epidemiol Glob Health ; 20: 101250, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816535

RESUMO

Introduction: Coronavirus disease-2019 (COVID-19) had a multidimensional impact on human life. It affects the health-related quality of life (HRQoL) which is a perceived measure of physical and mental health. We estimated the EuroQol utility value for COVID-19 and the associated factors for those managed at Siddha COVID care centres in Tamil Nadu. Methods: A cross-sectional study was conducted by a telephonic interview of 2000 randomly selected COVID-19 adults tested positive during June 2020 to Jan 2021. We collected sociodemographic, clinical and EQ-5D-5L profile. Mean EQ-5D-5L summary utility values and EQ-VAS scores were estimated. Multivariate regression was used to examine the factors associated with EQ-5D-5L. Study protocol was approved by the Institutional ethics committee of Government Siddha Medical College, Chennai (GSMC-CH-3401/ME-2/050/2021). The committee waived the written informed consent considering the pandemic situation of emerging infectious diseases. Results: We interviewed 1047 participants. Of the total 68% were males with the median age (IQR) of 38 (29-51) years. The mean EQ-5D-5L utility score and EQ-VAS scores are 0.98 ± 0.05 and 92.14 ± 0.39 respectively. COVID-19 asymptomatic group reported a mean utility score of 0.99 ± 0.03 which is relatively more than the symptomatic group (0.97 ± 0.06),. EQ-VAS score was also reported high among the asymptomatic (95.45 ± 5.95) than the symptomatic (91.40 ± 8.69COVID-19. Conclusion: The severity of illness and the comorbidity are significantly associated with a low HRQoL of COVID-19 patients.

13.
Glob Health Action ; 16(1): 2161231, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36621943

RESUMO

Due to the workload and lack of a critical mass of trained operational researchers within their ranks, health systems and programmes may not be able to dedicate sufficient time to conducting operational research (OR). Hence, they may need the technical support of operational researchers from research/academic organisations. Additionally, there is a knowledge gap regarding implementing differentiated tuberculosis (TB) care in programme settings. In this 'how we did it' paper, we share our experience of implementing a differentiated TB care model along with an inbuilt OR component in Tamil Nadu, a southern state in India. This was a health system initiative through a collaboration of the State TB cell with the Indian Council of Medical Research institutes and the World Health Organisation country office in India. The learnings are in the form of eleven tips: four broad principles (OR on priority areas and make it a health system initiative, implement simple and holistic ideas, embed OR within routine programme settings, aim for long-term engagement), four related to strategic planning (big team of investigators, joint leadership, decentralised decision-making, working in advance) and three about implementation planning (conducting pilots, smart use of e-tools and operational research publications at frequent intervals). These may act as a guide for other Indian states, high TB burden countries that want to implement differentiated care, and for operational researchers in providing technical assistance for strengthening implementation and conducting OR in health systems and programmes (TB or other health programmes). Following these tips may increase the chances of i) an enriching engagement, ii) policy/practice change, and iii) sustainable implementation.


Assuntos
Pesquisa Biomédica , Tuberculose , Humanos , Índia , Tuberculose/prevenção & controle , Programas Governamentais , Organizações
16.
Geospat Health ; 17(2)2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36468600

RESUMO

A complete sampling frame (CSF) is needed for the development of probability sampling structures; utilisation of a spatial sampling frame (SSF) was the objective of the present study. We used two sampling methods, simple random sampling (SRS) and stratified random sampling (STRS), to compare the prevalence estimates delivered by a CSF to that by a SSF when applied to self-reported hypertension and diabetes mellitus in a semi-urban setting and in a rural one. A CSF based on Geodatabase of all households and all individuals was available for our study that focused on adults aged 18-69 years in the two settings. A single digitized shapefile of solely household regions/structures as SSF was developed using Google Earth and employed for the study. The results from the two sampling frames were similar and not significantly different. All 95%CI calculations contained the prevalence rates of the two medical conditions except for one occasion based on STRS and CSF. The SRS based on CSF showed a minimum 95% CI width for diabetes mellitus, whereas SSF showed a minimum 95% CI width for hypertension. The coefficient of variation exceeded 10.0% on six occasions for CSF but only once for SSF, which was found to be as efficient as CSF.


Assuntos
Diabetes Mellitus , Hipertensão , Adulto , Humanos , Prevalência , Diabetes Mellitus/epidemiologia , Hipertensão/epidemiologia , Autorrelato , Projetos de Pesquisa
17.
BMC Immunol ; 23(1): 51, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36289478

RESUMO

BACKGROUND: Plasmacytoid and myeloid dendritic cells play a vital role in the protection against viral infections. In COVID-19, there is an impairment of dendritic cell (DC) function and interferon secretion which has been correlated with disease severity. RESULTS: In this study, we described the frequency of DC subsets and the plasma levels of Type I (IFNα, IFNß) and Type III Interferons (IFNλ1), IFNλ2) and IFNλ3) in seven groups of COVID-19 individuals, classified based on days since RT-PCR confirmation of SARS-CoV2 infection. Our data shows that the frequencies of pDC and mDC increase from Days 15-30 to Days 61-90 and plateau thereafter. Similarly, the levels of IFNα, IFNß, IFNλ1, IFNλ2 and IFNλ3 increase from Days 15-30 to Days 61-90 and plateau thereafter. COVID-19 patients with severe disease exhibit diminished frequencies of pDC and mDC and decreased levels of IFNα, IFNß, IFNλ1, IFNλ2 and IFNλ3. Finally, the percentages of DC subsets positively correlated with the levels of Type I and Type III IFNs. CONCLUSION: Thus, our study provides evidence of restoration of homeostatic levels in DC subset frequencies and circulating levels of Type I and Type III IFNs in convalescent COVID-19 individuals.


Assuntos
COVID-19 , Interferon Tipo I , Humanos , Interferon Tipo I/metabolismo , RNA Viral/metabolismo , SARS-CoV-2 , Células Dendríticas/metabolismo , Homeostase
18.
PLoS One ; 17(8): e0272042, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35939442

RESUMO

BACKGROUND: In the ongoing COVID-19 pandemic, an increased incidence of ROCM was noted in India among those infected with COVID. We determined risk factors for rhino-orbito-cerebral mucormycosis (ROCM) post Coronavirus disease 2019 (COVID-19) among those never and ever hospitalized for COVID-19 separately through a multicentric, hospital-based, unmatched case-control study across India. METHODS: We defined cases and controls as those with and without post-COVID ROCM, respectively. We compared their socio-demographics, co-morbidities, steroid use, glycaemic status, and practices. We calculated crude and adjusted odds ratio (AOR) with 95% confidence intervals (CI) through logistic regression. The covariates with a p-value for crude OR of less than 0·20 were considered for the regression model. RESULTS: Among hospitalised, we recruited 267 cases and 256 controls and 116 cases and 231 controls among never hospitalised. Risk factors (AOR; 95% CI) for post-COVID ROCM among the hospitalised were age 45-59 years (2·1; 1·4 to 3·1), having diabetes mellitus (4·9; 3·4 to 7·1), elevated plasma glucose (6·4; 2·4 to 17·2), steroid use (3·2; 2 to 5·2) and frequent nasal washing (4·8; 1·4 to 17). Among those never hospitalised, age ≥ 60 years (6·6; 3·3 to 13·3), having diabetes mellitus (6·7; 3·8 to 11·6), elevated plasma glucose (13·7; 2·2 to 84), steroid use (9·8; 5·8 to 16·6), and cloth facemask use (2·6; 1·5 to 4·5) were associated with increased risk of post-COVID ROCM. CONCLUSIONS: Hyperglycemia, irrespective of having diabetes mellitus and steroid use, was associated with an increased risk of ROCM independent of COVID-19 hospitalisation. Rational steroid usage and glucose monitoring may reduce the risk of post-COVID.


Assuntos
COVID-19 , Diabetes Mellitus , Hiperglicemia , Mucormicose , Doenças Orbitárias , Antifúngicos/uso terapêutico , Glicemia , Automonitorização da Glicemia , COVID-19/epidemiologia , Estudos de Casos e Controles , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Hospitalização , Humanos , Hiperglicemia/complicações , Hiperglicemia/tratamento farmacológico , Hiperglicemia/epidemiologia , Índia/epidemiologia , Pessoa de Meia-Idade , Mucormicose/tratamento farmacológico , Mucormicose/epidemiologia , Doenças Orbitárias/tratamento farmacológico , Pandemias
19.
PLoS One ; 17(7): e0270789, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35816497

RESUMO

BACKGROUND: India has experienced the second largest outbreak of COVID-19 globally, yet there is a paucity of studies analysing contact tracing data in the region which can optimise public health interventions (PHI's). METHODS: We analysed contact tracing data from Karnataka, India between 9 March and 21 July 2020. We estimated metrics of transmission including the reproduction number (R), overdispersion (k), secondary attack rate (SAR), and serial interval. R and k were jointly estimated using a Bayesian Markov Chain Monte Carlo approach. We studied determinants of risk of further transmission and risk of being symptomatic using Poisson regression models. FINDINGS: Up to 21 July 2020, we found 111 index cases that crossed the super-spreading threshold of ≥8 secondary cases. Among 956 confirmed traced cases, 8.7% of index cases had 14.4% of contacts but caused 80% of all secondary cases. Among 16715 contacts, overall SAR was 3.6% [95% CI, 3.4-3.9] and symptomatic cases were more infectious than asymptomatic cases (SAR 7.7% vs 2.0%; aRR 3.63 [3.04-4.34]). As compared to infectors aged 19-44 years, children were less infectious (aRR 0.21 [0.07-0.66] for 0-5 years and 0.47 [0.32-0.68] for 6-18 years). Infectors who were confirmed ≥4 days after symptom onset were associated with higher infectiousness (aRR 3.01 [2.11-4.31]). As compared to asymptomatic cases, symptomatic cases were 8.16 [3.29-20.24] times more likely to cause symptomatic infection in their secondary cases. Serial interval had a mean of 5.4 [4.4-6.4] days, and case fatality rate was 2.5% [2.4-2.7] which increased with age. CONCLUSION: We found significant heterogeneity in the individual-level transmissibility of SARS-CoV-2 which could not be explained by the degree of heterogeneity in the underlying number of contacts. To strengthen contact tracing in over-dispersed outbreaks, testing and tracing delays should be minimised and retrospective contact tracing should be implemented. Targeted measures to reduce potential superspreading events should be implemented. Interventions aimed at children might have a relatively small impact on reducing transmission owing to their low symptomaticity and infectivity. We propose that symptomatic cases could cause a snowballing effect on clinical severity and infectiousness across transmission generations; further studies are needed to confirm this finding.


Assuntos
COVID-19 , Busca de Comunicante , Teorema de Bayes , COVID-19/epidemiologia , Criança , Humanos , Índia/epidemiologia , Estudos Retrospectivos , SARS-CoV-2
20.
Int J Infect Dis ; 122: 693-702, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35843496

RESUMO

OBJECTIVES: India introduced BBV152/Covaxin and AZD1222/Covishield vaccines in January 2021. We estimated the effectiveness of these vaccines against severe COVID-19 among individuals aged ≥45 years. METHODS: We did a multi-centric, hospital-based, case-control study between May and July 2021. Cases were severe COVID-19 patients, and controls were COVID-19 negative individuals from 11 hospitals. Vaccine effectiveness (VE) was estimated for complete (2 doses ≥ 14 days) and partial (1 dose ≥ 21 days) vaccination; interval between two vaccine doses and vaccination against the Delta variant. We used the random effects logistic regression model to calculate the adjusted odds ratios (aOR) with a 95% confidence interval (CI) after adjusting for relevant known confounders. RESULTS: We enrolled 1143 cases and 2541 control patients. The VE of complete vaccination was 85% (95% CI: 79-89%) with AZD1222/Covishield and 71% (95% CI: 57-81%) with BBV152/Covaxin. The VE was highest for 6-8 weeks between two doses of AZD1222/Covishield (94%, 95% CI: 86-97%) and BBV152/Covaxin (93%, 95% CI: 34-99%). The VE estimates were similar against the Delta strain and sub-lineages. CONCLUSION: BBV152/Covaxin and AZD1222/Covishield were effective against severe COVID-19 among the Indian population during the period of dominance of the highly transmissible Delta variant in the second wave of the pandemic. An escalation of two-dose coverage with COVID-19 vaccines is critical to reduce severe COVID-19 and further mitigate the pandemic in the country.


Assuntos
COVID-19 , Vacinas contra Influenza , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Estudos de Casos e Controles , ChAdOx1 nCoV-19 , Hospitais , Humanos , SARS-CoV-2
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