Impact of asymptomatic infected individuals on epidemic transmission dynamics in multiplex networks with partial coupling

The theory of network science has attracted great interest of many researchers in the realm of biomathematics and public health,and numerous valuable epidemic models have been developed.In previous studies,it is common to set up a one-to-one correspondence between the nodes of a multi-layer network,ignoring the more complex situations in reality.In the present work,we explore this situation by setting up a partially coupled model of a two-layer network and investigating the impact of asymptomatic infected individuals on epidemics.We propose a self-discovery mechanism for asymptomatic infected individuals,taking into account situations such as nucleic acid testing in the community and individuals performing self-antigen testing during the epidemic.Considering these factors together,through the microscopic Markov chain approach(MMCA)and extensive Monte Carlo(MC)numerical simulations,we find that the greater the coupling between the networks,the more information dissemination is facilitated.In order to control the epidemics,more asymptomatic infected individuals should be made aware of their infection.Massive adoption of nucleic acid testing and individual adoption of antigenic self-testing can help to contain epidemic outbreaks.Meanwhile,the epidemic threshold of the proposed model is derived,and then miscellaneous factors affecting the epidemic threshold are also discussed.Current results are conducive to devising the prevention and control policies of pandemics.

Natural history of asymptomatic gallbladder stones in clinic without beds:A long-term prognosis over 10 years

BACKGROUND Several studies have explored the long-term prognosis of patients with asymp-tomatic gallbladder stones.These reports were primarily conducted in facilities equipped with beds for addressing symptomatic cases.AIM To report the long-term prognosis of patients with asymptomatic gallbladder stones in clinics without bed facilities.METHODS We investigated the prognoses of 237 patients diagnosed with asymptomatic gallbladder stones in clinics without beds between March 2010 and October 2022.When symptoms developed,patients were transferred to hospitals where appropriate treatment was possible.We investigated the asymptomatic and survival periods during the follow-up.RESULTS Among the 237 patients,214(90.3%)remained asymptomatic,with a mean asymptomatic period of 3898.9279±46.871 d(50-4111 d,10.7 years on average).Biliary complications developed in 23 patients(9.7%),with a mean survival period of 4010.0285±31.2788 d(53-4112 d,10.9 years on average).No patient died of biliary complications.CONCLUSION The long-term prognosis of asymptomatic gallbladder stones in clinics without beds was favorable.When the condition became symptomatic,the patients were transferred to hospitals with beds that could address it;thus,no deaths related to biliary complications were reported.This finding suggests that follow-up care in clinics without beds is possible.

Clinical profile and risk factors of symptomatic and asymptomatic hypoglycemia in neonates admitted to NICU in a tertiary care center: A cross-sectional study

Objective:To investigate the clinical profile and risk factors of symptomatic and asymptomatic hypoglycemia in neonates admitted to a neonatal intensive care unit in a tertiary care center.Methods:The prospective observational study was conducted in a tertiary care center in the Specialty Department of Pediatric.196 Newborn babies with blood glucose levels<45 mg/dL were examined with a simple random sampling method between December 2019 and November 2021.Maternal and neonatal risk factors and clinical signs were recorded and compared between symptomatic and asymptomatic cases.Results:The proportion of symptomatic hypoglycemia neonates born to gestational diabetes mellitus mothers was significantly higher(23.4%vs.8.4%)(P<0.05).Small for gestational age,low birth weight,respiratory distress syndrome,hypothermia,and endocrine disorders were risk factors.The death rate in asymptomatic hypoglycemia neonates was significantly higher(58%vs.39%)(P<0.05).Conclusions:The study indicates that maternal gestational diabetes mellitus is associated with symptomatic hypoglycemia and asymptomatic hypoglycemia is associated with neonatal mortality.It is important to take vigilance and timely interventions to address associated symptoms,particularly poor feeding,in the management of neonatal hypoglycemia.

Asymptomatic bile duct stones:The devil is in the details

Common bile duct(CBD)stones are a common biliary tract disease.For asymp-tomatic CBD stones,stone removal by endoscopic retrograde cholangiopancreato-graphy(ERCP)is recommended in available guidelines.Because asymptomatic CBD stones is a benign disease with no noticeable symptoms,the risk vs benefit strategy should be thoroughly considered before performing ERCP in these patients.Clinical care review,technical aspects of the procedure,and patient preferences should also be considered.

Clinical Effect of Yinhuang Qingfei Capsules in Treatment of Asymptomatic and Mild/Common Severe Acute Respiratory Syndrome Coronavirus 2 Infection:An Analysis of 242 Cases

[Objectives]To investigate the clinical effect of Yinhuang Qingfei capsules in the treatment of asymptomatic and mild/common severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection.[Methods]A total of 362 patients with SARS-CoV-2 infection were divided into the treatment group with 242 patients and control group with 120 patients according to their treatment regimen.The patients in the control group were given standard treatment regimen and those in the treatment group were given Yinhuang Qingfei capsules in addition to the treatment in the control group.The two groups were observed in terms of average length of hospital stay,mean time for nucleic acid clearance,TCM syndrome score,and progression to severe/critical illness,and clinical outcome was compared between the two groups.[Results]There was a significant difference in the overall response rate between the treatment group and the control group[97.52%(236/242)vs 95.00%(114/120),P<0.05].Compared with the control group,the treatment group had significantly shorter length of hospital stay and time for nucleic acid clearance(P<0.05).After 7 days of treatment,both groups had a significant change in TCM syndrome score,and there was a significant difference in TCM syndrome score between the two groups(P<0.05);after 15 days of treatment,both groups had a TCM syndrome score of 0.Progression to severe/critical illness was not observed in either group.[Conclusions]Compared with the standard treatment regimen alone,standard treatment regimen combined with Yinhuang Qingfei capsules can effectively shorten the length of hospital stay and time for nucleic acid clearance and improve TCM symptoms in patients with asymptomatic and mild/common SARS-CoV-2 infection.

A Campylobacteriosis Outbreak Caused by One Asymptomatic Food Handler Carrier

In August 2021,three students with diarrhea from the same school visited a local hospital in the S district of Beijing.An epidemic investigation showed that there were more students with diarrhea in the same school and they had one meal together.Campylobacter jejuni was isolated from both patients with diarrhea and asymptomatic food handlers;however,the latter also carried Campylobacter coli.Phylogenomic analysis showed that there was a campylobacteriosis outbreak among the students,and the asymptomatic food handler may have been the source of the infection.Routine inspection and surveillance for Campylobacter is needed for the food producing staff,particularly those cooking in the cafeteria in schools or other public food services.

Implication of Oxidative Stress and Antioxidant Defence Systems in Symptomatic and Asymptomatic Plasmodium falciparum Malaria Infection among Children Aged 1 to 15 Years in the Mount Cameroon Area

It is known that the pathogenicity of Plasmodium induces the breakdown of haemoglobin, which leads to the induction of oxidative stress. This study aimed to identify the possible effects of oxidative stress and antioxidant defence systems in symptomatic and asymptomatic Plasmodium falciparum malaria infection in children (1 - 15 years old) in the Mount Cameroon vicinity. This cross-sectional study involved blood samples collected from 473 children and examined for malaria parasitaemia. Full blood counts were performed using an automated haemoanalyser. Serum oxidative stress status (malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD) and vitamin C (Vit C)) were each determined by colorimetric enzymatic assays. The prevalence of malaria parasite infection was 32.1% among the participants. Out of that, 62.5% of patients with parasitaemia were symptomatic. Anaemia prevalence increased significantly with parasite density. MDA levels were significantly higher in patients with malaria symptoms than in those without symptoms. A significant and positive correlation was detected between MDA (r = 0.831, P < 0.05), NO (r = 0.779, P < 0.05), and malaria parasite density while, a significant and negative relationship occurred between parasite density and GSH (r = ?0.763, P < 0.05) and Vit C (r = ?0.826, P < 0.05) levels, SOD (r = ?0.621, P < 0.05) and CAT (r = ?0.817, P < 0.05) activities. The SOD activity and GSH level significantly decreased (P < 0.05) with an increase in the MDA levels. These findings showed that MDA and nitric oxide levels increased both in malaria participants with or without symptoms. A similar decrease in the antioxidant defence system was observed in both symptomatic and asymptomatic patients. Therefore, there is a need to develop public health policies that encourage routine diagnosis and treatment of malaria in seemingly healthy people (asymptomatic cases), and this will play an essential role in controlling malaria in tropical countries.

Remaining issues of recommended management in current guidelines for asymptomatic common bile duct stones

Current guidelines for treating asymptomatic common bile duct stones(CBDS)recommend stone removal,with endoscopic retrograde cholangiopan-creatography(ERCP)being the first treatment choice.When deciding on ERCP treatment for asymptomatic CBDS,the risk of ERCP-related complications and outcome of natural history of asymptomatic CBDS should be compared.The incidence rate of ERCP-related complications,particularly of post-ERCP pancreatitis for asymptomatic CBDS,was reportedly higher than that of symptomatic CBDS,increasing the risk of ERCP-related complications for asymptomatic CBDS compared with that previously reported for biliopancreatic diseases.Although studies have reported short-to middle-term outcomes of natural history of asymptomatic CBDS,its long-term natural history is not well known.Till date,there are no prospective studies that determined whether ERCP has a better outcome than no treatment in patients with asymptomatic CBDS or not.No randomized controlled trial has evaluated the risk of early and late ERCP-related complications vs the risk of biliary complications in the wait-and-see approach,suggesting that a change is needed in our perspective on endoscopic treatment for asymptomatic CBDS.Further studies examining long-term complication risks of ERCP and wait-and-see groups for asymptomatic CBDS are warranted to discuss whether routine endoscopic treatment for asymptomatic CBDS is justified or not.

Clinical and angiographic characteristics of asymptomatic restenosis after PCI

Objective To analyze the clinical and angiographic characteristics associated with asymptomatic versus symptomatic restenosis after percutaneous coronary intervention(PCI).Methods One hundred and sixty eight patients who underwent percutaneous revascularization and 6 month follow up angiography were recruited from 2001 to 2002, in which Fifty nine patients with angiographic restenosis ( ≥50% diameter stenosis) were analyzed. Multivariate analysis evaluated 24 clinical and angiographic variables, comparing those with and without angina. Results Restenosis occurred in 32 patients with clinical silence (55%) and 27 patients with angina. Male sex ( P =0.03 ), absence of antianginal therapy with nitrates ( P =0.002 ) ,greater reference diameter after the procedure ( P =0.04 ), greater reference diameter at follow up (P=0.01), and less lesion severity at 6 months ( P =0.04 ) were univariate predictors of asymptomatic restenosis. By multivariate analysis, only male, greater reference diameter at follow up, and less lesion severity at 6 months were associated with restenosis without angina.Conclusions Approximately half of patients with angiographic restenosis have no symptoms. The only multivariate predictors of silent restenosis at 6 months were male sex, greater reference diameter at follow up, and less lesion severity on follow up angiography.

Combination of serum gamma-glutamyltransferase and alkaline phosphatase in predicting the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis

BACKGROUND Gamma-glutamyltransferase(GGT) is one of the most important laboratory tests for the evaluation of liver damage. Through a long-term clinical observation of patients with secondary asymptomatic choledocholithiasis, we found that most patients had abnormal GGT serum levels.AIM To investigate the combination of serum GGT and alkaline phosphatase(ALP) in predicting the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis.METHODS In this retrospective cohort study, the clinical data of 829 patients with cholecystolithiasis admitted to the Third Affiliated Hospital of Zunyi Medical College from August 2014 to August 2017 were collected. Among these patients,151 patients had secondary asymptomatic choledocholithiasis and served as the observation group, and the remaining 678 cholecystolithiasis patients served as the control group. Serum liver function indexes were detected in both groups,and the receiver operating characteristic(commonly known as ROC) curves were constructed for markers showing statistical significances. The cutoff value,sensitivity, and specificity of each marker were calculated according to the ROC curves.RESULTS The overall incidence of asymptomatic choledocholithiasis secondary to cholecystolithiasis was 18.2%. The results of liver function indexes including serum aspartate aminotransferase, alanine aminotransferase, direct bilirubin and total bilirubin levels showed no significant differences between the two groups(P> 0.05). However, the serum GGT and ALP levels were significantly higher in the observation group than in the control group(P < 0.05). The ROC curve analysis showed that the area under the curve was 0.881(95%CI: 0.830-0.932), 0.647(95%CI: 0.583-0.711) and 0.923(0.892-0.953) for GGT, ALP, and GGT + ALP,respectively. The corresponding cut-off values of GGT and ALP were 95.5 U/L and 151.5 U/L, sensitivity were 90.8% and 65.1%, and specificity were 83.6% and59.8%, respectively. The sensitivity and specificity of GGT + ALP were 93.5% and85.1%, respectively.CONCLUSION An abnormally elevated serum GGT level has an important value in the diagnosis of asymptomatic choledocholithiasis secondary to cholecystolithiasis.The combination of serum GGT and ALP has better diagnostic performance. As a convenient, rapid and inexpensive test, it should be applied in secondary asymptomatic choledocholithiasis routine screening.

Risk factors for the development of post-endoscopic retrograde cholangiopancreatography pancreatitis in patients with asymptomatic common bile duct stones

BACKGROUND Previous studies have revealed that patients with asymptomatic common bile duct(CBD)stones are at a high risk of developing post-endoscopic retrograde cholangiopancreatography(ERCP)pancreatitis(PEP).However,no studies to date have addressed the risk factors for PEP in patients with asymptomatic CBD stones.AIM To examine the risk factors for PEP in patients with asymptomatic CBD stones.METHODS Using medical records of three institutions in Japan for 6 years,we identified a total of 1135 patients with choledocholithiasis including 967 symptomatic patients and 168 asymptomatic patients with native papilla who underwent therapeutic ERCP.We performed univariate and multivariate analyses to examine the risk factors for PEP in the 168 patients with asymptomatic CBD stones.RESULTS The overall incidence rate of PEP in all the patients with during study period was 4.7%(53/1135).Of the 168 patients with asymptomatic CBD stones,24(14.3%)developed PEP.In univariate analysis,precut sphincterotomy(P=0.009)and biliary balloon sphincter dilation(P=0.043)were significant risk factors for PEP.In multivariate analysis,precut sphincterotomy(P=0.002,95%CI:2.2-27.8,odds ratio=7.7),biliary balloon sphincter dilation(P=0.015,95%CI:1.4-17.3,odds ratio=4.9),and trainee endoscopists(P=0.048,95%CI:1.01-8.1,odds ratio=2.9)were significant risk factors for PEP.CONCLUSION ERCP for asymptomatic CBD stones should be performed by experienced endoscopists.When performing precut sphincterotomy or biliary balloon sphincter dilation in patients with asymptomatic CBD stones,the placement of a prophylactic pancreatic stent is strongly recommended to prevent PEP.

Gallbladder function and dynamics of bile flow in asymptomatic gallstone disease

AIM： To investigate the effects of gallbladder stones on motor functions of the gallbladder and the dynamics of bile flow in asymptomatic gallstone disease. METHODS： Quantitative hepatobiliary scintigraphy was performed to detect the parameters of gallbladder motor function [gallbladder ejection fraction （GBEF）, gallbladder visualization time （GBVT）, gallbladder time to peak activity （GBTmax）, gallbladder half emptying time （GBT1/2）, and transit time of bile to duodenum （TTBD）] in 24 patients with asymptomatic cholelithiasis who were diagnosed incidentally during routine abdominal ultrasonographic examination and 20 healthy subjects with normal gallbladder. RESULTS： Even though there was no significant difference in the clinical and laboratory parameters between the patient and control groups, all parameters of gallbladder function except TTBD were found to differ significantly between the two groups. GBEF in the patient group was decreased （P = 0.000） and GBVT, GBT GBT1/2 in the patient group were longer （P = 0.000, P = 0.015, P = 0.001, respectively）.there were not any clinical and laboratory findings, gallbladder filling and emptying could be impaired in patients with gallstone disease.

Multivariate predictive model for asymptomatic spontaneous bacterial peritonitis in patients with liver cirrhosis

BACKGROUNDSpontaneous bacterial peritonitis (SBP) is a detrimental infection of the asciticfluid in liver cirrhosis patients, with high mortality and morbidity. Earlydiagnosis and timely antibiotic administration have successfully decreased themortality rate to 20%-25%. However, many patients cannot be diagnosed in theearly stages due to the absence of classical SBP symptoms. Early diagnosis ofasymptomatic SBP remains a great challenge in the clinic.AIMTo establish a multivariate predictive model for early diagnosis of asymptomaticSBP using positive microbial cultures from liver cirrhosis patients with ascites.METHODSA total of 98 asymptomatic SBP patients and 98 ascites liver cirrhosis patients withnegative microbial cultures were included in the case and control groups,respectively. Multiple linear stepwise regression analysis was performed toidentify potential indicators for asymptomatic SBP diagnosis. The diagnosticperformance of the model was estimated using the receiver operatingcharacteristic curve.RESULTSPatients in the case group were more likely to have advanced disease stages,cirrhosis related-complications, worsened hematology and ascites, and higher mortality. Based on multivariate analysis, the predictive model was as follows: y (P) = 0.018 + 0.312 × MELD (model of end-stage liver disease) + 0.263 × PMN(ascites polymorphonuclear) + 0.184 × N (blood neutrophil percentage) + 0.233 ×HCC (hepatocellular carcinoma) + 0.189 × renal dysfunction. The area under thecurve value of the established model was 0.872, revealing its high diagnosticpotential. The diagnostic sensitivity was 73.5% (72/98), the specificity was 86.7%(85/98), and the diagnostic efficacy was 80.1%.CONCLUSIONOur predictive model is based on the MELD score, polymorphonuclear cells,blood N, hepatocellular carcinoma, and renal dysfunction. This model mayimprove the early diagnosis of asymptomatic SBP.

Afebrile, asymptomatic and non-thrombocytopenic Zika virus infection: don't miss it!

Zika virus infection is the present problematic arboviral disease. Classically, this disease cause febrile illness and can result in low platelet count. However, there are some new obervations on atypical clinical presentations of Zika virus infection that can make the diagnosis more difficult. The afebrile, asymptomatic and non-thrombocytopenic Zika virus infection can be seen in clinical practice and can lead to missed or delayed diagnosis.

Asymptomatic small intestinal ulcerative lesions:Obesity and Helicobacter pylori are likely to be risk factors

It is often difficult to explain why ulcerative lesions are found in the small intestine because there are no obvious aggressors such as gastric acid.In particular,the treatment of small intestinal ulcerative lesions in asymptomatic patients with no symptoms,normal physical examinations,and normal blood test findings is not well documented.According to a summary of capsule endoscopy studies in healthy subjects,approximately 10%of subjects have small intestinal mucosal breaks.The number of mucosal breaks in these instances is approximately 1-3.We examined small intestinal mucosal breaks in healthy subjects recruited from our past two studies.Mucosal breaks were observed in approximately 10%of subjects,and the average number was 0.24±1.21.The number of mucosal breaks in the small intestine was correlated with body mass index and was significantly higher in Helicobacter pylori-infected subjects and higher in males.These results indicate that 1-2 small ulcerative lesions,such as erosions in the small intestine,can be considered to be in the normal range,and close examination is not required.It is assumed that a follow-up medical examination is required for such asymptomatic persons.The presence of many small ulcerative lesions or an unequivocal ulcer indicates an abnormality for which close examination is desired.However,in many cases,it is sufficient to scrutinize after detecting anemia,but it is difficult to make a judgment due to insufficient reports,and future studies are required.

The influence of asymptomatic inflammatory prostatitis on the onset and progression of lower urinary tract symptoms in men with histologic benign prostatic hyperplasia

Benign prostatic hyperplasia(BPH)is a condition that greatly affects the quality of life of middle-aged and elderly men.Histopathologically,hyperplastic changes frequently occur in the prostate tissue of elderly men,the incidence of which has been reported to reach approximately 80% in men in their 70s.In clinical practice,approximately 25% of men with histologic BPH are assumed to experience lower urinary tract symptoms(LUTS)and receive some kind of treatment.In other words,there are some men with histologic BPH who do not exhibit LUTS.For that reason,many factors,such as the change in hormonal environment,the immune or autoimmune response,the alteration of gene expression,and so on,are thought to affect the onset and progression of LUTS in men with histologic BPH.One such factor that has long drawn attention is the presence of asymptomatic histological inflammation,which very often accompanies symptomatic BPH.Recent studies have suggested that asymptomatic histological inflammation causes repeated destruction,healing,and regeneration of the prostate tissue,leading to the enlargement of prostatic nodules,while at the same time causing stromal tissuepredominant remodeling of the prostate tissue,which can increase urination resistance and result in the condition changing from asymptomatic BPH to symptomatic BPH.In future,the biomolecular clarification of the significance of asymptomatic histological inflammation in the prostate tissue could help develop new treatment strategies for BPH accompanied by LUTS.

Asymptomatic primary biliary cirrhosis is not associated with increased frequency of cardiovascular disease

AIM: To estimate the prevalence of cardiovascular events in Primary biliary cirrhosis (PBC) and to determine whether this risk is higher within specific subgroups of patients with PBC. METHODS: We included 180 patients with PBC (cases) and 151 patients seen for HCV infection (controls). Medical records were reviewed and statistical analyses were performed as appropriate. RESULTS: When compared to controls, PBC patients were older, leaner and had higher serum levels of total cholesterol, high density lipoprotein and low density cholesterol. There were more females in the PBC group (91.7% vs 43%, P < 0.001). More control subjects had smoked than the PBC patients (63.6% vs 35%, P < 0.001). The prevalence of hypertension, diabetes, coronary artery disease and stroke was similar between the two groups. Seven percent of controls and 10% of cases developed any type of cardiovascular disease (P = 0.3). Only 36.7% were asymptomatic at diagnosis. Three cardiovascular events were documented among asymptomatic patients (4.5%) and fifteen among symptomatic patients (13.2%; P = 0.06). Among PBC patients with fatigue, 10 (13.5%) had a cardiovascular event compared to 7 (6.7%) among patients without fatigue (P = 0.1). CONCLUSION: Asymptomatic PBC patients do not have a greater frequency of cardiovascular disease; nor do patients suffering with fatigue.

Cholecystectomy for asymptomatic gallstones:Markov decision tree analysis

Gallstones are a common public health problem,especially in developed countries.There are an increasing number of patients who are diagnosed with gallstones due to increasing awareness and liberal use of imaging,with 22.6%-80% of gallstone patients being asymptomatic at the time of diagnosis.Despite being asymptomatic,this group of patients are still at life-long risk of developing symptoms and complications such as acute cholangitis and acute biliary pancreatitis.Hence,while early prophylactic cholecystectomy may have some benefits in selected groups of patients,the current standard practice is to recommend cholecystectomy only after symptoms or complications occur.After reviewing the current evidence about the natural course of asymptomatic gallstones,complications of cholecystectomy,quality of life outcomes,and economic outcomes,we recommend that the option of cholecystectomy should be discussed with all asymptomatic gallstone patients.Disclosure of material information is essential for patients to make an informed choice for prophylactic cholecystectomy.It is for the patient to decide on watchful waiting or prophylactic cholecystectomy,and not for the medical community to make a blanket policy of watchful waiting for asymptomatic gallstone patients.For patients with high-risk profiles,it is clinically justifiable to advocate cholecystectomy to minimize the likelihood of morbidity due to complications.

Serodiagnosis of asymptomatic dengue infection

Dengue virus(DENV) is a mosquito-transmitted virus that is expanding across the world,The incidence of dengue infection,especially severe disease,has been increasing,DENV consist of 4 serotypes of single stranded RNA viruses(D1-D4) in the genus Flavivirus,family Flaviviridae,Majority of dengue infections are asymptomatic cases,which cause difficulty in disease control and are important in dengue surveillance,There is still no gold standard to diagnose asymptomatic dengue infection,Plaque reduction neutralization test(PRNT) has been developed for many purposes such as immunological study,clinical study,vaccine trial and is currently the most sensitive and specific method for serological surveillance,However,PRNT shows some degree of cross reaction among different dengue serotypes especially secondary dengue infection cases and to other flaviviruses,Moreover,various modification since the beginning make PRNT lack of inter-laboratory standardization which is an important issue,This paper discusses the important of asymptomatic dengue infection and its diagnostic method.

Molecular detection of SARS-CoV-2 being challenged by virus variation and asymptomatic infection

Coronavirus disease 2019(COVID-19)has been a pandemic for more than a year.With the expanding second wave of the pandemic in winter,the continuous evolution of SARS-CoV-2 has brought new issues,including the significance of virus mutations in infection and the detection of asymptomatic infection.In this review,we first introduced several major SARS-CoV-2 mutations since the COVID-19 outbreak and then mentioned the widely used molecular detection techniques to diagnose COVID-19,primarily focusing on their strengths and limitations.We further discussed the effects of viral genetic variation and asymptomatic infection on the molecular detection of SARS-CoV-2 infection.The review finally summarized useful insights into the molecular diagnosis of COVID-19 under the special situation being challenged by virus mutation and asymptomatic infection.