Search
What are you looking for?
Start main content

Press Releases

Press Releases

https://www.med.cuhk.edu.hk/press-releases/cuhk-finds-that-the-coronavirus-can-persist-in-stool-after-its-clearance-in-respiratory-tract-will-conduct-stool-test-for-people-in-quarantine-camps-for-early-identification
https://www.med.cuhk.edu.hk/press-releases/cuhk-finds-that-the-coronavirus-can-persist-in-stool-after-its-clearance-in-respiratory-tract-will-conduct-stool-test-for-people-in-quarantine-camps-for-early-identification

CUHK Finds that the Coronavirus Can Persist in Stool after Its Clearance in Respiratory Tract Will Conduct Stool Test for People in Quarantine Camps for Early Identification

The Faculty of Medicine at The Chinese University of Hong Kong (CU Medicine) analysed more than 300 specimens (including sputum, nasopharyngeal swabs, deep throat saliva, blood, urine and stool) from 14 Hong Kong patients confirmed with COVID-19 and discovered that the virus was detectable in the fecal samples of all patients, regardless of the degree of illness. Three out of 14 patients still had viruses in their stool samples even though the virus was no longer found in sputum, nasopharyngeal and deep throat saliva samples. This finding suggests that virus shedding in stool is common and can be an alternative screening tool. Importantly, we should not overlook the potential risk of environmental contamination by virus shedding in stool.   

 

In view of our finding, CU Medicine will in the first stage screen stool and saliva for 100 asymptomatic close contacts admitted to the quarantine centers. This will help determine whether stool test can effectively detect COVID-19 in asymptomatic persons. 

 

 

All Studied Patients Have COVID-19 Virus Detected in their Fecal Samples

 

The research team collected and analysed more than 300 specimens from 14 confirmed cases, including respiratory, blood, urine and stool samples, to understand the virus distribution in human body. Below are the main findings:   

  • Sputum has the highest amount of coronavirus, more than 300 times as found in deep throat saliva.
  • All patients had their stool tested positive during their course of illness, regardless of the degree of illness.
  • The virus load in stool is comparable to deep throat saliva.
  • 3 out of 14 patients still had virus in their stool samples for 1-2 days even though the virus was no longer found in respiratory samples.
  • Blood positive rate was low.
  • All urine samples were negative.
CU Medicine analysed more than 300 specimens from 14 Hong Kong patients confirmed with COVID-19, and found all patients have their stool test positive of the coronavirus. (From left) Prof. Paul CHAN, Chairman of the Department of Microbiology; Prof. Francis CHAN, Dean of the Faculty of Medicine and Director of the Centre for Gut Microbiota Research; and Prof. David HUI, Chairman of the Department of Medicine and Therapeutics, at CU Medicine. 

CU Medicine analysed more than 300 specimens from 14 Hong Kong patients confirmed with COVID-19, and found all patients have their stool test positive of the coronavirus. (From left) Prof. Paul CHAN, Chairman of the Department of Microbiology; Prof. Francis CHAN, Dean of the Faculty of Medicine and Director of the Centre for Gut Microbiota Research; and Prof. David HUI, Chairman of the Department of Medicine and Therapeutics, at CU Medicine. 

Professor Paul Kay Sheung CHAN, Chairman of the Department of Microbiology, CU Medicine, remarked, “Risk of transmission is the highest from respiratory tract.   Gastrointestinal tract is also an important route not to be ignored. For persons with productive cough, sputum is the best choice of self-collect specimen. For persons who cannot produce sputum, in addition to deep throat saliva, stool could be an alternative tool that enables early case identification in the community.”

Prof. Paul CHAN states that 3 patients still had coronavirus in their stool samples even though the virus was no longer found in respiratory samples. This finding should not be ignored.  

Professor Paul Kay Sheung CHAN, Chairman of the Department of Microbiology, CU Medicine, remarked, “Risk of transmission is the highest from respiratory tract.   Gastrointestinal tract is also an important route not to be ignored. For persons with productive cough, sputum is the best choice of self-collect specimen. For persons who cannot produce sputum, in addition to deep throat saliva, stool could be an alternative tool that enables early case identification in the community.”

 

Prof. Francis CHAN reminds the public that virus shedding in stool may impose health hazard to others. Caretakers and food handlers should be particularly vigilant about their hand hygiene.

Prof. Francis CHAN reminds the public that virus shedding in stool may impose health hazard to others. Caretakers and food handlers should be particularly vigilant about their hand hygiene.

Professor Francis KL CHAN, Dean of the Faculty of Medicine and Director of the Centre for Gut Microbiota Research at CUHK remarked, “Our study suggests that virus shedding in stool may have public health implications. First, it may serve as an alternative screening tool in people without respiratory symptoms. Second, virus shedding in stool may impose health hazard to others. Caretakers and food handlers should be particularly vigilant about their hand hygiene.”

 

Prof. David HUI explains that coronavirus shedding in stool can contaminate the environment and the virus can be transmitted through mucosal surfaces of eyes, nose and mouth after people touch the contaminated surface.

Prof. David HUI explains that coronavirus shedding in stool can contaminate the environment and the virus can be transmitted through mucosal surfaces of eyes, nose and mouth after people touch the contaminated surface.

Professor David Shu Cheong HUI, Chairman of the Department of Medicine and Therapeutics and Stanley Ho Professor of Respiratory Medicine at CU Medicine, explained that virus shedding in stool could contaminate the environment and the virus could be transmitted through mucosal surfaces of eyes, nose and mouth after people touch the contaminated surface. He reminded the public to stay alert on hand hygiene. He remarked, “The public are reminded of filling enough water into U-shaped water traps connected to bathroom floor drains and to close the toilet lid when they flush. All these measures help reduce the risk of infection.”

More Press Releases

CU Medicine Found SARS-CoV2 in Infants' Stool A Coronavirus Testing Centre Is Established for Paediatric Population to Identify Silent Carriers

CU Medicine Found SARS-CoV2 in Infants' Stool A Coronavirus Testing Centre Is Established for Paediatric Population to Identify Silent Carriers

Research
CU Medicine Develops a Probiotic Formula to Target Imbalance in Gut Microbiota in COVID-19

CU Medicine Develops a Probiotic Formula to Target Imbalance in Gut Microbiota in COVID-19

Research
CU Medicine Offers Free Stool Screening Test for COVID-19 in Children arriving at Airport

CU Medicine Offers Free Stool Screening Test for COVID-19 in Children arriving at Airport

Clinical service
CU Medicine supported by the Hospital Authority to launch HK’s first large-scale Long COVID survey, aiming to inform the government on impact of long COVID on healthcare services

CU Medicine supported by the Hospital Authority to launch HK’s first large-scale Long COVID survey, aiming to inform the government on impact of long COVID on healthcare services

Research
HKUMed-CU Medicine joint study shows that vaccinated individuals develop more robust and broadly reactive antibody responses against SARS-CoV-2 variants than the unvaccinated after an Omicron infection

HKUMed-CU Medicine joint study shows that vaccinated individuals develop more robust and broadly reactive antibody responses against SARS-CoV-2 variants than the unvaccinated after an Omicron infection

Research
HKUMed-CU Medicine joint study finds that third dose of Comirnaty has better protection from COVID-19 variant Omicron

HKUMed-CU Medicine joint study finds that third dose of Comirnaty has better protection from COVID-19 variant Omicron

Research
CU Medicine Survey Shows Only 25% of Unvaccinated People Intend to Get Inoculated in the Coming Six Months “Multiple Incentives” are Urgently Needed

CU Medicine Survey Shows Only 25% of Unvaccinated People Intend to Get Inoculated in the Coming Six Months “Multiple Incentives” are Urgently Needed

Research
CU Medicine Estimates 20,000 COVID-19 Hidden Infections in Hong Kong  All Vaccinated Persons in HK Developed Neutralising Antibody After Two Doses  Urgent Call for the Largely Unprotected Population to Get Vaccinated

CU Medicine Estimates 20,000 COVID-19 Hidden Infections in Hong Kong All Vaccinated Persons in HK Developed Neutralising Antibody After Two Doses Urgent Call for the Largely Unprotected Population to Get Vaccinated

Research
A Global Study Led by CU Medicine and HKUMed Discovers  a Hepatitis C Virus Drug as Potent Treatment for COVID-19

A Global Study Led by CU Medicine and HKUMed Discovers a Hepatitis C Virus Drug as Potent Treatment for COVID-19

Research
CU Medicine Study Suggests Toddlers are at High Risk of Being  “Silent Spreaders of SARS-CoV2 Infection”

CU Medicine Study Suggests Toddlers are at High Risk of Being “Silent Spreaders of SARS-CoV2 Infection”

Research
CU Medicine Study Shows Modulation of Gut Microbiota  Helps Enhance Safety and Efficacy of COVID-19 Vaccine

CU Medicine Study Shows Modulation of Gut Microbiota Helps Enhance Safety and Efficacy of COVID-19 Vaccine

Research
CU Medicine Finds New Evidence for Link between Gut Microbiome and COVID-19 Severity Microbiome Imbalance Might Influence “Long COVID” Risk

CU Medicine Finds New Evidence for Link between Gut Microbiome and COVID-19 Severity Microbiome Imbalance Might Influence “Long COVID” Risk

Research
CU Medicine Survey Shows Government Recommendation as the Strongest Driver for COVID-19 Vaccine Acceptance

CU Medicine Survey Shows Government Recommendation as the Strongest Driver for COVID-19 Vaccine Acceptance

Research
40% of Hong Kong People Show Gut Dysbiosis Comparable to that of COVID-19 Patients CUHK Microbiome Immunity Formula Hastens Recovery of COVID-19 Patients and Offers Hope to Boost Immunity

40% of Hong Kong People Show Gut Dysbiosis Comparable to that of COVID-19 Patients CUHK Microbiome Immunity Formula Hastens Recovery of COVID-19 Patients and Offers Hope to Boost Immunity

Research
CU Medicine Recruits 3,000 Persons to Investigate Hidden Infection and Break the Obstacles in Containing COVID-19 in Hong Kong

CU Medicine Recruits 3,000 Persons to Investigate Hidden Infection and Break the Obstacles in Containing COVID-19 in Hong Kong

Research
CU Medicine Announces the Community Response Study Results During the Early Phase of the COVID-19 Outbreak in Hong Kong

CU Medicine Announces the Community Response Study Results During the Early Phase of the COVID-19 Outbreak in Hong Kong

Research
CUHK Establishes Asia’s First Microbiota Transplantation and Research Centre Hope for New Strategies in Disease Prevention and Cure

CUHK Establishes Asia’s First Microbiota Transplantation and Research Centre Hope for New Strategies in Disease Prevention and Cure

Research
CUHK Conducts Asia's Largest Clinical Study on Life-threatening Infections caused by RSV and Influenza in Hong Kong Adults and Elderly

CUHK Conducts Asia's Largest Clinical Study on Life-threatening Infections caused by RSV and Influenza in Hong Kong Adults and Elderly

Research
CUHK Research Findings on Severe Human Swine Flu in Hong Kong

CUHK Research Findings on Severe Human Swine Flu in Hong Kong

Research
Large-scale clinical study shows CU Medicine (SIM01) microbiome formula reduces risk of infections including COVID-19

Large-scale clinical study shows CU Medicine (SIM01) microbiome formula reduces risk of infections including COVID-19

Research
中大醫學院就行政長官今日(10月19日)發表2022施政報告的回應 (Chinese Version Only)

中大醫學院就行政長官今日(10月19日)發表2022施政報告的回應 (Chinese Version Only)

Response
CUHK study advises residential care homes for the elderly to maintain current infection control practices

CUHK study advises residential care homes for the elderly to maintain current infection control practices

Research
CUHK-HKU collaborative study finds about 80% lower risk of death among COVID-19 inpatients prescribed oral medication and the risk of hospital admission in outpatients is significantly reduced by nearly 90%

CUHK-HKU collaborative study finds about 80% lower risk of death among COVID-19 inpatients prescribed oral medication and the risk of hospital admission in outpatients is significantly reduced by nearly 90%

Research
CUHK develops a real-time bioinformatics platform to predict COVID-19 vaccine effectiveness against SARS-CoV-2 variants with 95% accuracy

CUHK develops a real-time bioinformatics platform to predict COVID-19 vaccine effectiveness against SARS-CoV-2 variants with 95% accuracy

Research
COVID-19 pandemic disrupted the daily lives of schoolchildren in Hong Kong; Proportion of overweight and obese kids more than doubled

COVID-19 pandemic disrupted the daily lives of schoolchildren in Hong Kong; Proportion of overweight and obese kids more than doubled

Research
CUHK receives HK$150 million donation from Li Ka Shing Foundation in support of research and development of biomedical technologies

CUHK receives HK$150 million donation from Li Ka Shing Foundation in support of research and development of biomedical technologies

Donation
CUHK finds that a booster vaccine dose is effective in retriggering antibodies in breast milk that protect babies

CUHK finds that a booster vaccine dose is effective in retriggering antibodies in breast milk that protect babies

Research
CUHK study suggests COVID-19 booster shot is key to protecting against infection among high-risk populations and from variants of concern

CUHK study suggests COVID-19 booster shot is key to protecting against infection among high-risk populations and from variants of concern

Research
CUHK Clinical Trial Centre collaborates with CUHK Medical Centre to conduct Hong Kong’s first clinical trial of novel oral treatment specifically developed for COVID-19

CUHK Clinical Trial Centre collaborates with CUHK Medical Centre to conduct Hong Kong’s first clinical trial of novel oral treatment specifically developed for COVID-19

Research
CUHK researchers discover distinct gut microbial signatures for prediction, diagnosis and treatment of long COVID

CUHK researchers discover distinct gut microbial signatures for prediction, diagnosis and treatment of long COVID

Research
CU Medicine study shows a higher prevalence of dry eye disease  among post-COVID-19 patients

CU Medicine study shows a higher prevalence of dry eye disease among post-COVID-19 patients

Research
CU Medicine and Kowloon City District Office co-organise community COVID-19 vaccination programme targeting 2,000 residents, especially young children

CU Medicine and Kowloon City District Office co-organise community COVID-19 vaccination programme targeting 2,000 residents, especially young children

Health Campaign
A joint HKU-CUHK study finds that smoking  increases the risk of COVID-19

A joint HKU-CUHK study finds that smoking increases the risk of COVID-19

Research
中大醫學院就2022-23財政預算案的回應 (Chinese Version Only)

中大醫學院就2022-23財政預算案的回應 (Chinese Version Only)

Response
CUHK-HKU collaborative research finds a new inflammatory activation pathway in  blood vessels after SARS-CoV-2 infection

CUHK-HKU collaborative research finds a new inflammatory activation pathway in blood vessels after SARS-CoV-2 infection

Research
CU Medicine study shows distinct gut microbial profile associated with long COVID

CU Medicine study shows distinct gut microbial profile associated with long COVID

Research
Assessment of Omicron outbreak in Hong Kong after reimplementation of some of the toughest social distancing measures effective from 7 January

Assessment of Omicron outbreak in Hong Kong after reimplementation of some of the toughest social distancing measures effective from 7 January

Research
HKUMed-CU Medicine joint study finds COVID-19 variant Omicron significantly reduces virus neutralisation ability of BioNTech vaccine

HKUMed-CU Medicine joint study finds COVID-19 variant Omicron significantly reduces virus neutralisation ability of BioNTech vaccine

Research
Joint CUHK-HKU study discovers efficacy of COVID-19 vaccines correlates with a probiotic bacterium, Bifidobacterium adolescentis

Joint CUHK-HKU study discovers efficacy of COVID-19 vaccines correlates with a probiotic bacterium, Bifidobacterium adolescentis

Research
CUHK study sheds light on novel mechanism and treatment of acute kidney injury in COVID-19 patients

CUHK study sheds light on novel mechanism and treatment of acute kidney injury in COVID-19 patients

Research
CUHK Study Suggests a Standardised Experimental Setup is the Key to Optimise  Performance of COVID-19 Nucleic Acid Tests

CUHK Study Suggests a Standardised Experimental Setup is the Key to Optimise Performance of COVID-19 Nucleic Acid Tests

Research
Clarification -- 中大醫學院澄清啟事 (Chinese Version Only)

Clarification -- 中大醫學院澄清啟事 (Chinese Version Only)

Response
CUHK Study Demonstrates a 2.5-fold Increase in Myopia Incidence in Children  During COVID-19 Pandemic Due to Less Time Outdoors and More Time on Screens

CUHK Study Demonstrates a 2.5-fold Increase in Myopia Incidence in Children During COVID-19 Pandemic Due to Less Time Outdoors and More Time on Screens

Research
CUHK Develops a Novel Faecal Test that can Detect Polyps and Early Colon Cancers  with Sensitivity Over 90%

CUHK Develops a Novel Faecal Test that can Detect Polyps and Early Colon Cancers with Sensitivity Over 90%

Research
CU Medicine Study Shows Recovered Mothers Transfer COVID-19 Antibodies to Newborn Babies

CU Medicine Study Shows Recovered Mothers Transfer COVID-19 Antibodies to Newborn Babies

Research
CU Medicine and International Surgeons Suggest Patients with Positive COVID-19 Results Should Delay Surgery for Seven Weeks to Reduce Death Risk

CU Medicine and International Surgeons Suggest Patients with Positive COVID-19 Results Should Delay Surgery for Seven Weeks to Reduce Death Risk

International collaboration
CUHK Introduces Nasal Strip Sampling for COVID-19 Test As a Superior Tool for Surveillance in a Wide Age-Range Population

CUHK Introduces Nasal Strip Sampling for COVID-19 Test As a Superior Tool for Surveillance in a Wide Age-Range Population

Research
CUHK Study Shows Exposure Settings Impact COVID-19 Transmission With Entertainment Setting Showing Propensity for Widespread Dispersion

CUHK Study Shows Exposure Settings Impact COVID-19 Transmission With Entertainment Setting Showing Propensity for Widespread Dispersion

Research
Most Deaths from COVID-19 in Hong Kong are of 60 Years Old or Above CUHK Initiated International Effort in Devising Strategies to Protect Older People with Dementia amid COVID-19 Pandemic

Most Deaths from COVID-19 in Hong Kong are of 60 Years Old or Above CUHK Initiated International Effort in Devising Strategies to Protect Older People with Dementia amid COVID-19 Pandemic

Research
CU Medicine Study Shows Liver Injury is Common and Prognostic in COVID-19 Patients

CU Medicine Study Shows Liver Injury is Common and Prognostic in COVID-19 Patients

Research
CUHK Researchers Uncover Diabetes as a Potential Risk Factor for COVID-19,  and Possible Mechanisms

CUHK Researchers Uncover Diabetes as a Potential Risk Factor for COVID-19, and Possible Mechanisms

Research
CU Medicine Survey Shows Global Urological Services have been Significantly Deferred due to COVID-19 Pandemic

CU Medicine Survey Shows Global Urological Services have been Significantly Deferred due to COVID-19 Pandemic

Research
The Helmsley Charitable Trust Funds Asian Research into Babies’ Gut Microbiota and Crohn’s Disease

The Helmsley Charitable Trust Funds Asian Research into Babies’ Gut Microbiota and Crohn’s Disease

Research
CUHK Study Suggests Preoperative Screening for Obstructive Sleep Apnoea to  Lower Risk of Postoperative Cardiovascular Events

CUHK Study Suggests Preoperative Screening for Obstructive Sleep Apnoea to Lower Risk of Postoperative Cardiovascular Events

Research
CUHK-Designed Intervention Package Proves Effective to Increase Influenza Vaccine Uptake in Hong Kong Young Children

CUHK-Designed Intervention Package Proves Effective to Increase Influenza Vaccine Uptake in Hong Kong Young Children

Research
CUHK Establishes Hong Kong Hub of Paediatric Excellence (HK HOPE) Multidisciplinary Efforts Across the Globe to Advance Children’s Health and Well-being

CUHK Establishes Hong Kong Hub of Paediatric Excellence (HK HOPE) Multidisciplinary Efforts Across the Globe to Advance Children’s Health and Well-being

Health Campaign
CUHK Reveals the Key to a Successful HPV Vaccination Programme

CUHK Reveals the Key to a Successful HPV Vaccination Programme

Research
Professor Francis CHAN as the First Chinese Honoured with the American College of Gastroenterology International Leadership Award 2018

Professor Francis CHAN as the First Chinese Honoured with the American College of Gastroenterology International Leadership Award 2018

Awards and honors
CUHK Pioneers in Introducing Museum-Based Observational Skills into Medical Education

CUHK Pioneers in Introducing Museum-Based Observational Skills into Medical Education

Education
CUHK Announces World’s First Systematic Review of the Global Incidence and Prevalence of Inflammatory Bowel Diseases in the 21st Century Reveals Surge in Hong Kong in past 30 years

CUHK Announces World’s First Systematic Review of the Global Incidence and Prevalence of Inflammatory Bowel Diseases in the 21st Century Reveals Surge in Hong Kong in past 30 years

Research
CUHK Proves Efficacy of Home-Based Management Approach of Obstructive Sleep Apnoea Applicable to 50% of Public Hospital Adult Cases with Waiting Time Reduced by 80%

CUHK Proves Efficacy of Home-Based Management Approach of Obstructive Sleep Apnoea Applicable to 50% of Public Hospital Adult Cases with Waiting Time Reduced by 80%

Research
CUHK Proves Rotavirus Vaccine Highly Effective for HK Children

CUHK Proves Rotavirus Vaccine Highly Effective for HK Children

Research
CUHK World’s First Study Sets a New Direction on Aspirin Use after Lower Gastrointestinal Hemorrhage

CUHK World’s First Study Sets a New Direction on Aspirin Use after Lower Gastrointestinal Hemorrhage

Research
CUHK Research Shows 1 in 5 Throat Cancer Patients in HK is HPV infected

CUHK Research Shows 1 in 5 Throat Cancer Patients in HK is HPV infected

Research
CUHK Conducts Hong Kong’s First Study on Seven Common Respiratory Viruses Revealing Respiratory Syncytial Virus and Influenza A as Prevalent Fatal Types

CUHK Conducts Hong Kong’s First Study on Seven Common Respiratory Viruses Revealing Respiratory Syncytial Virus and Influenza A as Prevalent Fatal Types

Research
Asia’s First Research by CUHK on Patients’ Lifestyle Reveals Personalised Modification Programme Effective in Reducing Severity of OSA

Asia’s First Research by CUHK on Patients’ Lifestyle Reveals Personalised Modification Programme Effective in Reducing Severity of OSA

Research
CUHK Highlights the Significance of Hospital Infection Control System in Controlling MERS

CUHK Highlights the Significance of Hospital Infection Control System in Controlling MERS

Research
CUHK Reveals Hepatitis B Prevalence Among Pregnant Women Remains High Despite More Than 25 Years of Universal Hepatitis B Vaccination

CUHK Reveals Hepatitis B Prevalence Among Pregnant Women Remains High Despite More Than 25 Years of Universal Hepatitis B Vaccination

Research
CUHK discovers that 40% of Individuals at Risk of Coronary Heart Disease have Pre-cancerous Bowel Tumors

CUHK discovers that 40% of Individuals at Risk of Coronary Heart Disease have Pre-cancerous Bowel Tumors

Research
CUHK will hold 'SARS A Decade On: A Conference for the Health Professionals'

CUHK will hold 'SARS A Decade On: A Conference for the Health Professionals'

Symposium
CUHK Research Reveals New Influenza Vaccine Offers More Effective Control over Influenza in Hong Kong

CUHK Research Reveals New Influenza Vaccine Offers More Effective Control over Influenza in Hong Kong

Research
Bowel Cancer Will Become Top Cancer in Hong Kong CUHK Introduces Colon Pill Camera to Prevent Bowel Cancer

Bowel Cancer Will Become Top Cancer in Hong Kong CUHK Introduces Colon Pill Camera to Prevent Bowel Cancer

Surgical advancement
CUHK Discovers Up to 30% of Asymptomatic Subjects in Hong Kong Suffered from Pre-cancerous Bowel Tumors

CUHK Discovers Up to 30% of Asymptomatic Subjects in Hong Kong Suffered from Pre-cancerous Bowel Tumors

Research
CUHK Introduces Double Balloon Enteroscopy Service to Manage Small Bowel Diseases

CUHK Introduces Double Balloon Enteroscopy Service to Manage Small Bowel Diseases

Clinical service
Predicting Your Colorectal-polyp Risk with CUHK Colorectal-polyp Prediction Index (CU-CPI)

Predicting Your Colorectal-polyp Risk with CUHK Colorectal-polyp Prediction Index (CU-CPI)

Clinical service

Our Expert List

Many experts under the Faculty of Medicine are available for media interview.
Please click here for the expert list or contact us.