Effect of the Timing of Amubarvimab/Romlusevimab (BRII-196/198) Administration on Progression to Severe Disease in Elderly Patients with COVID-19 Infection: A Retrospective Cohort Study

Objective Early intervention with neutralizing antibodies is considered to be effective in preventing disease progression in patients with mild to moderate COVID-19 infection. Elderly patients are the most susceptible and at a higher risk of COVID-19 infection. The present study aimed to assess the necessity and possible clinical benefits of the early administration of Amubarvimab/Romlusevimab (BRII-196/198) in the elderly population. Methods The present study was designed as a retrospective, multi-center cohort study conducted with 90 COVID-19 patients aged over 60, who were divided into two groups based on the timing of the administration of BRII-196/198 (administration at ≤ 3 days or > 3 days from the onset of infection symptoms). Results The ≤ 3 days group exhibited a greater positive effect (HR 5.94, 95% CI, 1.42–24.83;P < 0.01), with only 2 patients among 21 patients (9.52%) exhibiting disease progression, compared to the 31 patients among the 69 patients (44.93%) of the > 3 days group who exhibited disease progression. The multivariate Cox regression analysis revealed low flow oxygen support prior to BRII-196/198 administration (HR 3.53, 95% CI 1.42–8.77, P < 0.01) and PLT class (HR 3.68, 95% CI 1.37–9.91, P < 0.01) as independent predictors of disease progression. Conclusions In elderly patients with mild or moderate COVID-19 disease, who do not require oxygen support and had the risk factors for disease progression to severe COVID-19 disease, the administration of BRII-196/198 within 3 days resulted in a beneficial trend in terms of preventing disease progression.

Artificial Neural Network Dual Hesitant Fermatean Fuzzy Implementation in Transportation of COVID-19 Vaccine

This article, in order to address impreciseness, initiated the notion of dual hesitant fermatean fuzzy sets (DHFFSs), as a generalization of the combination of dual hesitant fuzzy set (DHFS), dual hesitant Pythagorean fuzzy set (DHPFS) and Fermatean fuzzy set (FFS). The authors defined the fundamental set of operations for DHFFS. Additionally, the authors have also proposed two ranking functions and an accuracy function for the ordering of this novel set. In order to facilitate the pragmatic implementation of DHFFS in optimization, the authors formulated three types of transportation problem with dual hesitant Fermatean fuzzy (DHFF) parameters. To optimize the DHFF-TP, an algorithm was proposed with the help of one of the proposed ranking functions. Artificial neural network is also applied to the transportation problems in DHFF environment. A numerical example based on the transportation of COVID-19 vaccine with DHFF cost has also been carried out to validate out to validate our technique.

Potential mechanisms between psychotic-like experiences and suicidal ideation in the context of COVID-19: A longitudinal study.

OBJECTIVE: Although many studies have found an association between psychotic-like experiences (PLEs) and suicidal ideation (SI), the underlying psychological mechanisms have not been well established. Therefore, we conducted a longitudinal study in technical secondary school and college students to explore the role of fear-response to the COVID-19 and depression in the association between PLEs and SI in the context of the COVID-19 pandemic. METHODS: PLEs were assessed using the 15-item Positive Subscale of the Community Assessment of Psychic Experiences (CAPE-P15). Depression, fear, and SI were assessed using the Psychological Questionnaire for Public Health Emergency (PQPHE). PLEs were evaluated before the pandemic (T1), and fear, depression, and SI were measured during the pandemic (T2). RESULT: A total of 938 students completed both waves of the survey through electronic questionnaires. PLEs, fear, depression, and SI were all correlated with each other (all p < 0.01). T2 depression partly (58.2 %) mediated the relationship between T1 PLEs and T2 SI (b = 0.15, 95%CI = 0.10, 0.22). T2 Fear moderated the relationship between T1 PLEs and T2 depression (b = 0.05, 95%CI = 0.01, 0.09) and the relationship between T1 PLEs and T2 SI (b = 0.11, 95%CI = 0.06, 0.16). CONCLUSION: PLEs are both directly and indirectly related to SI. Depression can result from PLEs and lead to the subsequent SI. Additionally, high levels of fear during the COVID-19 pandemic can aggravate the adverse impact of PLEs on mental health problems. These findings provide potential targets for future suicide prevention.

The Usability, Feasibility, Acceptability, and Efficacy of Digital Mental Health Services in the COVID-19 Pandemic: Scoping Review, Systematic Review, and Meta-analysis.

BACKGROUND: After the rapid spread of the novel SARS-CoV-2, the short-term and long-term mental health impacts of the pandemic on the public, in particular on susceptible individuals, have been reported worldwide. Although digital mental health services expand accessibility while removing many barriers to in-person therapy, their usability, feasibility, acceptability, and efficacy require continued monitoring during the initial phase of the pandemic and its aftermath. OBJECTIVE: In this study, we aimed to understand what mental health services are offered, whether they are practical or acceptable, and to what extent digital mental health services are effective in response to the COVID-19 pandemic across high-income and low- and middle-income countries. METHODS: This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the PRISMA Extension for Scoping Reviews (PRISMA-ScR) guideline. We implemented searches in PubMed (MEDLINE), Embase, PsycINFO, and Cochrane databases for studies that were published between December 2019 and November 2021 and that involved the use of digital mental health services. Two review authors screened, assessed, and extracted studies independently. The protocol was registered on the International Prospective Register of Systematic Reviews. RESULTS: This review identified 7506 articles through database searching. In total, 65 (0.9%) studies from 18 countries with 67,884 participants were eligible for the scoping review. Of the 65 studies, 16 (24.6%) were included in the meta-analysis. A total of 15 (23.1%) studies measured the usability; 31 (47.7%) studies evaluated the feasibility; 29 (44.6%) studies assessed the acceptability; and 51 (78.5%) studies assessed the efficacy. Web-based programs (21/65, 32.3%), videoconferencing platforms (16/65, 24.6%), smartphone apps (14/65, 21.5%), and SMS text messaging (5/65, 7.7%) were the main techniques. Psychotherapy (44/65, 67.7%) followed by psychoeducation (6/65, 9.2%) and psychological support (5/65, 7.7%) were commonly used. The results of the meta-analysis showed that digital mental health interventions were associated with a small reduction in depressive symptoms (standardized mean difference=-0.49; 95% CI -0.74 to -0.24; P<.001) and a moderate reduction in anxiety symptoms (standardized mean difference=-0.66; 95% CI -1.23 to -1.0; P=.02) significantly. CONCLUSIONS: The findings suggest that digital mental health interventions may be practical and helpful for the general population, at-risk individuals, and patients with preexisting mental disorders across high-income and middle-income countries. An expanded research agenda is needed to apply different strategies for addressing diverse psychological needs and develop integrated mental health services in the post-COVID-19 era. TRIAL REGISTRATION: PROSPERO CRD42022307695; https://tinyurl.com/2jcuwjym.

Psychotic-like experiences during COVID-19 lockdown among adolescents: Prevalence, risk and protective factors.

OBJECTIVE: Although plenty of evidence has shown the huge negative impact of COVID-19 on individuals' mental health conditions, little is known about its impact on the psychotic-like experiences (PLEs) in the general population. We aim to explore the prevalence of PLEs and relevant influential factors among adolescents during COVID-19 lockdown. METHODS: A total of 3234 students completed one online survey between April to May 2020. PLEs were assessed using the 15-item Positive Subscale of the Community Assessment of Psychic Experiences (CAPE-P15). Resilience, social support, childhood trauma, and a series of socio-demographic factors were also evaluated. RESULTS: In this sample, 51.4 % adolescents reported having at least one PLE, while 11.6 % experienced PLEs frequently during COVID-19 lockdown. Senior high school students showed more frequent PLEs than college students (p < 0.001). Female gender (OR = 1.77), history of mental disorders (OR = 3.07) or chronic physical illness (OR = 2.04), having relatives or friends being infected with COVID-19 (OR = 3.12), longer daily exposure to media coverage of the COVID-19 (OR = 1.60), and more childhood trauma (OR = 1.54-3.49) were correlated with more frequent PLEs, while higher resilience (OR = 0.35-0.54) and more perceived social support (OR = 0.63-0.72) were associated with decreased odds for frequent PLEs. Additionally, there were several differences among the influential factors between senior high school and college students. CONCLUSIONS: PLEs were relatively common among Chinese adolescents, with higher prevalence among senior high school students during COVID-19 lockdown. Adolescents with specific characteristics should receive more attention in the development of intervention measures in mental health during pandemic lockdown.

A review on indoor airborne transmission of COVID-19– modelling and mitigation approaches

In the past few years, significant efforts have been made to investigate the transmission of COVID-19. This paper provides a review of the COVID-19 airborne transmission modeling and mitigation strategies. The simulation models here are classified into airborne transmission infectious risk models and numerical approaches for spatiotemporal airborne transmissions. Mathematical descriptions and assumptions on which these models have been based are discussed. Input data used in previous simulation studies to assess the dispersion of COVID-19 are extracted and reported. Moreover, measurements performed to study the COVID-19 airborne transmission within indoor environments are introduced to support validations for anticipated future modeling studies. Transmission mitigation strategies recommended in recent studies have been classified to include modifying occupancy and ventilation operations, using filters and air purifiers, installing ultraviolet (UV) air disinfection systems, and personal protection compliance, such as wearing masks and social distancing. The application of mitigation strategies to various building types, such as educational, office, public, residential, and hospital, is reviewed. Recommendations for future works are also discussed based on the current apparent knowledge gaps covering both modeling and mitigation approaches. Our findings show that different transmission mitigation measures were recommended for various indoor environments;however, there is no conclusive work reporting their combined effects on the level of mitigation that may be achieved. Moreover, further studies should be conducted to understand better the balance between approaches to mitigating the viral transmissions in buildings and building energy consumption.

Development of a Bayesian inference model for assessing ventilation condition based on CO2 meters in primary schools

Outdoor fresh air ventilation plays a significant role in reducing airborne transmission of diseases in indoor spaces. School classrooms are considerably challenged during the COVID-19 pandemic because of the increasing need for in-person education, untimely and incompleted vaccinations, high occupancy density, and uncertain ventilation conditions. Many schools started to use CO2 meters to indicate air quality, but how to interpret the data remains unclear. Many uncertainties are also involved, including manual readings, student numbers and schedules, uncertain CO2 generation rates, and variable indoor and ambient conditions. This study proposed a Bayesian inference approach with sensitivity analysis to understand CO2 readings in four primary schools by identifying uncertainties and calibrating key parameters. The outdoor ventilation rate, CO2 generation rate, and occupancy level were identified as the top sensitive parameters for indoor CO2 levels. The occupancy schedule becomes critical when the CO2 data are limited, whereas a 15-min measurement interval could capture dynamic CO2 profiles well even without the occupancy information. Hourly CO2 recording should be avoided because it failed to capture peak values and overestimated the ventilation rates. For the four primary school rooms, the calibrated ventilation rate with a 95% confidence level for fall condition is 1.96±0.31 ACH for Room #1 (165 m3 and 20 occupancies) with mechanical ventilation, and for the rest of the naturally ventilated rooms, it is 0.40±0.08 ACH for Room #2 (236 m3 and 21 occupancies), 0.30±0.04 or 0.79±0.06 ACH depending on occupancy schedules for Room #3 (236 m3 and 19 occupancies), 0.40±0.32,0.48±0.37,0.72±0.39 ACH for Room #4 (231 m3 and 8–9 occupancies) for three consecutive days.

Application of serum antibody detection in the identification of transmission chain of COVID-19

Objective: To explore the transmission chain of COVID-19 by serum antibody detection, and to provide scientific evidence for the prevention and control of the epidemic.

Spatial region-resolved proteome map reveals mechanism of COVID-19-associated heart injury.

Direct myocardial and vascular injuries due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-driven inflammation is the leading cause of acute cardiac injury associated with coronavirus disease 2019 (COVID-19). However, in-depth knowledge of the injury characteristics of the heart affected by inflammation is lacking. In this study, using a quantitative spatial proteomics strategy that combines comparative anatomy, laser-capture microdissection, and histological examination, we establish a region-resolved proteome map of the myocardia and microvessels with obvious inflammatory cells from hearts of patients with COVID-19. A series of molecular dysfunctions of myocardia and microvessels is observed in different cardiac regions. The myocardia and microvessels of the left atrial are the most susceptible to virus infection and inflammatory storm, suggesting more attention should be paid to the lesion and treatment of these two parts. These results can guide in improving clinical treatments for cardiovascular diseases associated with COVID-19.

Guest Editorial

This mini-special issue of the IEEE Transactions on Microwave Theory and Techniques includes five expanded articles from the seventh IEEE MTT-S International Wireless Symposium (IEEE IWS 2020) held virtually on September 20–23, 2020, in response to the worldwide COVID-19 pandemic.

Ribavirin Treatment for Critically Ill COVID-19 Patients: An Observational Study.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has spread all over the world resulting in high mortality, yet no specific antiviral treatment has been recommended. METHODS: A retrospective descriptive study was conducted involving 19 consecutive critically ill patients during January 27, 2020 to April 18, 2020. Ribavirin was given at 0.15g q8h orally upon ICU admission for 7 to 21 days. Here, 28-day mortality, lower respiratory tract specimens (ETA), and ribavirin side effect on the day of ICU admission (Day 1), Day 7, Day 14 and Day 21 were analyzed. RESULTS: All the nineteen critically ill COVID-19 patients (14 males and 5 females, median age 56yr) survived through to the 28th day of observations with 6 patients (31.58%) being discharged from the ICU. The SARS-CoV-2 viral positivity in sputum/ETA was 100% (19/19) on Day 1, 73.68% (14/19) on Day 7, 57.89% (11/19) on Day 14 and 36.84% (7/19) on Day 21. Ribavirin side effect was not observed in these patients. CONCLUSION: Ribavirin is well tolerated in critically ill patients with COVID-19 and may benefit COVID-19 patients through increasing the virus clearance.

The Bidirectional Associations Between Insomnia and Psychotic-Like Experiences Before and During the COVID-19 Pandemic.

STUDY OBJECTIVES: Previous literature supports that insomnia is predictive of subsequent psychotic-like experiences (PLEs) in the general population. However, there is a lack of empirical data on the reverse causality between the two variables and on the correlation between the symptom severity of insomnia and PLEs. This study aimed to explore the bidirectional associations between insomnia and PLEs before and during the COVID-19 pandemic. METHODS: A total of 938 students aged 14-25 years completed both waves of the survey before and during the pandemic (the first wave: October 2019 to November 2019; the second wave: April 2020 to May 2020). PLEs were assessed using the 15-item positive subscale of the community assessment of psychic experiences (CAPE-P15), and insomnia was assessed using three questions on difficulty initiating sleep, difficulty maintaining sleep, and early morning awakening. RESULTS: Students with baseline insomnia were more likely to exhibit new-onset PLEs during the pandemic (OR: 5.13, 95% CI: 2.54-10.38), while no significant predictive effect of insomnia was found for the persistence and severity of PLEs. Meanwhile, baseline PLEs not only predicted the presence of insomnia during the pandemic (OR: 2.14, 95% CI: 1.25-3.65) but also correlated with its severity (B: 0.89, 95% CI: 0.47-1.31). CONCLUSION: The study provides the first piece of evidence for the bidirectional association between insomnia and PLEs in the general population. However, although insomnia has an important predictive role in the occurrence of PLEs, it does not predict the persistence and development of PLEs, suggesting that there is a more complex mechanism underlying the process.

OM-85 Broncho-Vaxom®, a Bacterial Lysate, Reduces SARS-CoV-2 Binding Proteins on Human Bronchial Epithelial Cells.

In clinical studies, OM-85 Broncho-Vaxom®, a bacterial lysate, reduced viral respiratory tract infection. Infection of epithelial cells by SARS-CoV-2 depends on the interaction of its spike-protein (S-protein) with host cell membrane proteins. In this study, we investigated the effect of OM-85 on the expression of S-protein binding proteins by human bronchial epithelial cells. Human bronchial epithelial cells were treated with OM-85 over 5 days. The expression of SARS-CoV-2 receptor angiotensin converting enzyme 2 (ACE2), transmembrane protease serine subtype 2 (TMPRSS2), dipeptidyl peptidase-4 (DPP4), and a disintegrin and metalloprotease 17 (ADAM17) were determined by Western blotting and quantitative RT-PCR. Soluble (s)ACE2, heparan sulfate, heparanase, and hyaluronic acid were assessed by ELISA. OM-85 significantly reduced the expression of ACE2 (p < 0.001), TMPRSS2 (p < 0.001), DPP4 (p < 0.005), and cellular heparan sulfate (p < 0.01), while ADAM17 (p < 0.02) expression was significantly upregulated. Furthermore, OM-85 increased the level of sACE2 (p < 0.05), hyaluronic acid (p < 0.002), and hyaluronan synthase 1 (p < 0.01). Consequently, the infection by a SARS-CoV-2 spike protein pseudo-typed lentivirus was reduced in cells pretreated with OM-85. All effects of OM-85 were concentration- and time-dependent. The results suggest that OM-85 might reduce the binding of SARS-CoV-2 S-protein to epithelial cells by modification of host cell membrane proteins and specific glycosaminoglycans. Thus, OM-85 might be considered as an add-on for COVID-19 therapy.

Case Report: Prolonged VV-ECMO (111 Days) Support in a Patient With Severe COVID-19.

Venovenous extracorporeal membrane oxygenation (VV-ECMO) may be a lifesaving rescue therapy for patients with severe coronavirus disease 2019 (COVID-19). However, little is known regarding the efficacy of prolonged ECMO (duration longer than 14 days) in patients with COVID-19. In this case report, we report the successful use of prolonged VV-ECMO (111 days) in a 61-year-old man with severe COVID-19. Given the high mortality rate of severe COVID-19, this case provided evidence for use of prolonged VV-ECMO as supportive care in patients with severe COVID-19.

Malnutrition is associated with hyperinflammation and immunosuppression in COVID-19 patients: A prospective observational study.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is spreading globally and has caused many deaths. This study investigated, for the first time, COVID-19 patients' nutrition status and its effects on their inflammatory and immune responses. METHODS: Forty-seven COVID-19 patients were recruited for this prospective study. According to the subjective global assessment at admission, patients were divided into the normal nutrition (NN), risk of malnutrition (RMN), or MN group. Serum cytokines and whole blood T-cell subpopulations were measured to assess the inflammatory and immune responses in COVID-19 patients. Analysis of covariance and χ2 tests were used. RESULTS: On admission, the incidences of MN and the RMN in COVID-19 patients were 17.0% and 38.3%, respectively. The MN group had a higher proportion with severe/critical COVID-19 and a longer hospitalization duration than the NN group. Serum interleukin (IL) 6 concentrations were elevated in 97.9% of the patients and were the highest in malnourished patients. The IL-4 and IL-10 levels were elevated in 46.8% and 48.9% of the patients, respectively. The proportion of CD8+ T cells was significantly lower in the MN group than in the NN group. CONCLUSION: A high proportion of COVID-19 patients are malnourished or at risk of malnuourishment, especially those with severe disease. MN is associated with hyperinflammation and immunosuppression in COVID-19 patients, and it may contribute to disease progression.

Structural basis for SARS-CoV-2 neutralizing antibodies with novel binding epitopes.

The ongoing Coronavirus Disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) threatens global public health and economy unprecedentedly, requiring accelerating development of prophylactic and therapeutic interventions. Molecular understanding of neutralizing antibodies (NAbs) would greatly help advance the development of monoclonal antibody (mAb) therapy, as well as the design of next generation recombinant vaccines. Here, we applied H2L2 transgenic mice encoding the human immunoglobulin variable regions, together with a state-of-the-art antibody discovery platform to immunize and isolate NAbs. From a large panel of isolated antibodies, 25 antibodies showed potent neutralizing activities at sub-nanomolar levels by engaging the spike receptor-binding domain (RBD). Importantly, one human NAb, termed PR1077, from the H2L2 platform and 2 humanized NAb, including PR953 and PR961, were further characterized and subjected for subsequent structural analysis. High-resolution X-ray crystallography structures unveiled novel epitopes on the receptor-binding motif (RBM) for PR1077 and PR953, which directly compete with human angiotensin-converting enzyme 2 (hACE2) for binding, and a novel non-blocking epitope on the neighboring site near RBM for PR961. Moreover, we further tested the antiviral efficiency of PR1077 in the Ad5-hACE2 transduction mouse model of COVID-19. A single injection provided potent protection against SARS-CoV-2 infection in either prophylactic or treatment groups. Taken together, these results shed light on the development of mAb-related therapeutic interventions for COVID-19.

Changes in psychotic-like experiences and related influential factors in technical secondary school and college students during COVID-19.

OBJECTIVE: Although students have been found to be at high risk of distress during the COVID-19 pandemic, little is known about the pandemic's impact on psychotic-like experiences (PLEs). We conducted a study in technical secondary school and college students before and during the pandemic to explore changes in PLEs and relevant influential factors. METHODS: A total of 938 students completed both waves of the survey through electronic questionnaires. PLEs were assessed using the 15-item Positive Subscale of the Community Assessment of Psychic Experiences (CAPE-P15). Childhood trauma, perceived stress, resilience, and demographic factors were evaluated at baseline, and psychological status was measured during the pandemic. RESULTS: The overall CAPE-P15 scores significantly decreased during the pandemic. Students with persistent PLEs showed the most severe COVID-19 related psychological symptoms, followed by new-onset and remitted individuals; those without PLEs exhibited the mildest symptoms (all p < .001). A single parent family (OR = 4.707), more childhood trauma (OR = 1.056), and a higher family income (OR = 1.658) were predictive of new-onset PLEs during the pandemic, while better resilience was a protective factor, associated with remission of previous PLEs (OR = 0.932). CONCLUSIONS: Despite a downward trend in the prevalence of PLEs during the pandemic, PLEs predict greater serious psychological impact due to COVID-19, especially for students with persistent PLEs. Interventions that cultivate students' resilience are urgently needed to reduce PLEs and improve mental health, especially for students from single parent households or those who have experienced childhood trauma.

Clinical Findings of COVID-19 Patients Admitted to Intensive Care Units in Guangdong Province, China: A Multicenter, Retrospective, Observational Study.

Background: Information about critically ill patients with coronavirus disease 2019 (COVID-19) in China but outside of Wuhan is scarce. We aimed to describe the clinical features, treatment, and outcomes of patients with COVID-19 admitted to the intensive care unit (ICU) in Guangdong Province. Methods: In this multicenter, retrospective, observational study, we enrolled consecutive patients with COVID-19 who were admitted to seven ICUs in Guangdong Province. Demographic data, symptoms, laboratory findings, comorbidities, treatment, and outcomes were collected. Data were compared between patients with and without intubation. Results: A total of 45 COVID-19 patients required ICU admission in the study hospitals [mean age 56.7 ± 15.4 years, 29 males (64.4%)]. The most common symptoms at onset were fever and cough. Most patients presented with lymphopenia and elevated lactate dehydrogenase. Treatment with antiviral drugs was initiated in all patients. Thirty-six patients (80%) developed acute respiratory distress syndrome at ICU admission, and 15 (33.3%) septic shock. Twenty patients (44.4%) were intubated, and 10 (22.2%) received extracorporeal membrane oxygenation. The 60-day mortality was 4.4% (2 of 45). Conclusion: COVID-19 patients admitted to ICU were characterized by fever, lymphopenia, acute respiratory failure, and multiple organ dysfunction. The mortality of ICU patients in Guangdong Province was relatively low with a small sample size.

Proximity to people with COVID-19 and anxiety among community residents during the epidemic in Guangzhou, China.

The recent outbreak of a novel coronavirus pneumonia (COVID-19) may have acute psychological consequences, both in relation to the impact of the virus itself and the restrictions imposed to tackle its spread. We conducted an online survey of 403 residents in Guangzhou, China. We found the prevalence of anxiety (defined as Generalized Anxiety Disorder-7 score ≥5) was 37.7%, and anxiety was significantly and moderately correlated with worry about COVID-19. Higher anxiety levels in community residents was associated with the presence of individuals with COVID-19 in the same building; a longer time spent each day gathering information about the virus; and choosing social media as their preferred source of information. Our findings provide an insight into the psychological support and guidance about information sources that are required in this type of public health emergency.

Ecological damage of submerged macrophytes by fresh cyanobacteria (FC) and cyanobacterial decomposition solution (CDS)

To investigate the deleterious ecological effects of cyanobacteria on submerged macrophytes, this study investigated the effects of different concentrations of fresh cyanobacteria (FC) and cyanobacteria decomposition solution (CDS) on an experimental group of submerged macrophytes (Vallisneria natans (Lour.) Hara and Myriophyllum verticillatum Linn.). The results showed that FC and CDS not only lead to decrease in biomass and significant changes in enzyme activity and chlorophyll content in tissue, but also affected the permeability of cell membranes. The extent of damage was in the order CDS >FC, and the comprehensive stress resistance of Vallisneria natans (2.994) was more than that of Myriophyllum verticillatum (2.895). In addition, semi-permeable membranes can reduce plant damage by FC and CDS, but cannot completely prevent it. FC and CDS mainly affected the relative distribution of microbial genera on the surface of aquatic plants (p <0.05). Furthermore, CDS caused irreversible damage to plant cells and induced programmed cell death (PCD) of plants to accelerate their decline. Therefore, FC and CDS may be one of the main reasons for the decline in submerged vegetation. This study provides a scientific basis for evaluating the harmful effects of cyanobacteria on submerged macrophytes.