Sinopharm COVID-19 & Latest Influenza Vaccines (Protects against Flu and H1N1 Viruses) / PCR COVID Testing / Serology Tests for Travellers & Serology Testing to Certify Vaccination status. Make your Appointment at Tel: 6694 1661

How do Asymptomatic COVID-19 cases affect the COVID-19 Pandemic?

"File:14 Hegasy COVID-19 Q EN.svg" by Iñaki LL is licensed under CC BY-SA 4.0

Asymptomatic or Presymptomatic ‘Silent’ Transmission

Asymptomatic: people who carry the active virus in their body but never develop any symptoms

Presymptomatic: people who have been infected and are incubating the virus but don't yet show symptoms

Very mildly symptomatic: people who feel a little unwell from a COVID-19 infection but continue to come in close contact with others

The percentage of the population infected with COVID-19 implied by the official case count and the serology survey differs widely (Ref : The Economist – Uncertainty’s Principals, Science & Technology 2 May 20). Samples of mass testing in various cities have shown actual infection rates ranging from 2.5% to 20%.

According to a study by the Center for Infectious Disease Research and Policy, University of Minnesota, many asymptomatic COVID-19 cases are undetected and there are indications that screening symptomatic contacts with a single throat swab test for SARS-CoV-2 might lead to an underestimate of the rate of infection and that asymptomatic persons can repeatedly revert between positive and negative PCR results on throat specimens.

The Centre for Evidence-Based Medicine, University of Oxford found that between 5% and 80% of people testing positive for SARS-CoV-2 may be asymptomatic, presymptomatic or show mild symptoms. Thus symptom-based screening will miss cases, perhaps a lot of them. Their research also found children and young adults can be asymptomatic.

COVID-19 SARS-CoV-2 Virus Information

Prevention Measures for COVID-19

COVID-19 Latest Updates & Health Tips

COVID-19 Asymptomatic 'Silent' Transmission

Risk Factors for COVID-19 Complications

COVID-19 Prognostic Tool

Infectious Viral Shedding

Another study by the Academy of Medicine, Singapore found that the infectious period of SARS-CoV-2 in symptomatic individuals may begin around 2 days before the onset of symptoms, and persists for about 7-10 days after the onset of symptoms. Viable virus was not found after the second week of illness despite the persistence of PCR detection of RNA (that is a false positive PCR test). Thus viral RNA detection by PCR does not equate to infectiousness or viable virus. A small but important study from Germany found that the degree of viral shedding was very high in the first week of symptoms. Infectious virus was cultured from throat and lung specimens in the first week of symptoms, but none after day 8 in spite of high viral loads detected by regular PCR tests.

Scientists from the University of Texas at Austin in a study to be published in the journal, Emerging Infectious Diseases found that the serial interval (time between one person developing the symptoms of a condition and a second person becoming infected and developing symptoms) for SARS-CoV-2 was approximately 4-5 days. The shorter the serial interval makes an epidemic harder to contain and more likely to spread quickly.

A modelling paper in Science suggests that in China before the lockdown, undiscovered cases — mainly people with "mild, limited or no symptoms" — were less infectious than known cases but were still possibly responsible for 79% of transmission, because so many of them continued to congregate or travel while contagious.

It is estimated by other papers from Singapore and China that people who had not yet developed symptoms transmitted around 6-13% of the cases studied. People can transmit the virus before symptoms begin during the incubation period, and the time between transmission and symptoms could be anything from 2-14 days.

< COVID Toes in otherwise Asymptomatic patients

Some Pre-symptomatic patients have displayed this condition.

COVID-19 Health Statistics

Researchers from China's Center for Disease Control and Prevention in a study of 72,000 COVID-19 patients found a 2.3% death rate.

A total of 81% of cases in a JAMA study were classified as mild, meaning they did not result in pneumonia or resulted in only mild pneumonia. Fourteen percent of cases were severe (marked by difficulty breathing), and 5% were critical (respiratory failure, septic shock, and/or multiple organ dysfunction or failure).

COVID-19 is less deadly but more transmissible than SARS or MERS. So looking on the bright side, based on the statistics, 97.7% of infected COVID-19 cases will survive. Upwards of 70% depending on your health status, will be asymptomatic. The remaining cases might display mild to more serious symptoms if you have any of the risk factors (Use this Prognostic Tool to assess your COVID-19 risk of complications).

Continue to take Safety preventive measures until the COVID-19 vaccine becomes available. This is estimated to be in the second half of 2021, according to GSK & Sanofi, the 2 biggest vaccine makers in the world.

COVID SARS-CoV-2 Life cycle / Viral structure / Immune response

Get Vaccinated!

COVID Vaccine & Booster - Sinopharm vaccine
Flu Vaccine
Childhood & Adult Vaccine schedule (Refer to NAIS & NCIS)

Up to $400 per Medisave Account per year can be used for Vaccinations under the National Adult & Childhood Immunisation Schedule - Influenza, Pneumococcal (PCV13/PPSV), Human Papillomavirus (HPV2/HPV4), Hepatitis B, Tetanus, Diphtheria & Pertussis (Tdap), Measles, Mumps & Rubella (MMR) and Chickenpox (Varicella)

Pain Relief Management & Treatment, Vaccinations, Health Screening, COVID & Allergy Testing, Dermatology Treatments, Minor Surgical Procedures

Pain Relief Management, Treatment & Therapy

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Allergy Testing

Minor Surgical Procedure

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Vaccinations -Sinopharm / Flu / NAIS / NCIS Immunization Schedules

Pre-Departure PCR Swab Test / Serology Testing

COVID-19 Sinopharm Vaccine & Booster

Sinopharm COVID-19 Vaccine is available @ MD International Medical Centre. Make a Vaccination or Booster Appointment at Tel: 6694 1661.

Sinopharm BBIBP-CorV vaccine has now been approved for use by private clinics in Singapore against the COVID-19 virus under the Special Access Route. It is the first China-made vaccine to be approved by the World Health Organisation (WHO).

To date, more than a billion doses of the Sinopharm BBIBP-CorV have been administered. The vaccine has also been approved for use in over 50 countries around the world.

Inactivated vaccines are a tried-and-tested form of vaccine technology which is used in other well-established vaccines, such as the Flu and Hepatitis B vaccines.

Effects of COVID-19 on the Brain

COVID Symptoms to watch out for:

SARS-CoV-2 Virus Infection of Human Organ Tissues through Cell ACE-2 Receptors:

Singapore Ministry of Health Recommendation:

For persons who have already completed their Primary series with mRNA vaccines and are recommended to get a booster, but are unable to take another dose of mRNA vaccines for medical reasons, they may boost using one dose of Sinopharm vaccine. The booster should be taken six months after mRNA dose 2 (M-M-S).

For persons who are unable to take the 2nd dose of mRNA vaccines for medical reasons, they may complete their vaccination with the Sinopharm vaccine. 2 doses of the Sinopharm vaccine is recommended to complete the Primary series. The 2nd Sinopharm dose should be taken 28 days after the 1st Sinopharm dose (M-S-S).

For recovered persons who had not completed a primary series before infection:

For persons who have recovered from a COVID-19 infection but received 1 dose or none of COVID-19 vaccination prior, they may receive 2 doses of the Sinopharm vaccine (28 days interval between doses), 3 months after the date of infection to complete a primary vaccination series (Recovered-S-S or S-Recovered-S-S or M-Recovered-S-S).

For persons who have recovered from a COVID-19 infection and had received 2 doses of Sinovac or Sinopharm vaccines prior, they may receive 1 dose of Sinopharm after 3 months from the date of infection to complete a primary vaccination series (S-S-Recovered-S).

Health Assessment & Screening Packages

Health Assessment

Health Screening Packages

Up to $400 per Medisave Account per year can be used for Vaccinations under the National Adult & Childhood Immunisation Schedule - Influenza, Pneumococcal (PCV13/PPSV), Human Papillomavirus (HPV2/HPV4), Hepatitis B, Tetanus, Diphtheria & Pertussis (Tdap), Measles, Mumps & Rubella (MMR) and Chickenpox (Varicella)

Part of the National Influenza Sentinel Surveillance programme with MOH. If you have a fever of > 38 degrees with a cough, our clinic is able to test for COVID-19. For children below 12 years old with clinical diagnosis of HFMD (eg fever, oral ulcers, rash), our clinic can test for Hand Foot & Mouth Disease (The tests are for surveillance purposes only).

Latest Influenza Vaccine

Asymptomatic patients may display no symptoms of illness. Vulnerable people should get vaccinated against Influenza which protects susceptible people from, as well as exclude the Flu and H1N1 viruses should they start to show URTI or ARI symptoms.

a. Vaccination decreases the risk of co-infection with COVID-19.

b. Vaccination reduces the burden of respiratory illnesses in the healthcare system.

The latest Influenza Vaccine is now available. It protects against the Flu and H1N1 Viruses. Ministry of Health Safety protocols are adhered to at all times for the safe vaccination of you and your family.

* Importance of Keeping your Vaccinations Up-to-date

Co-infection of COVID-19 with other infectious diseases is possible

Reduce your risk of getting sick with COVID-19

Make sure your vaccinations are up-to-date. People older than 65 years, and those with many underlying conditions, such as those who are immunocompromised or with significant liver disease, are recommended to receive vaccinations against Influenza and pneumococcal disease (PCV). Click here for Vaccination schedules (NAIS/NCIS).
Do not delay getting medical care for your underlying condition because of COVID-19. MD International Medical Centre has contingency MOH infection prevention protocols to protect you from getting COVID-19 if you need care for your underlying condition.
Continue your medications and do not change your treatment plan without talking to your doctor.
Make sure that you have at least a two-week supply of your chronic disease medications.
Call MDIMC @ Tel: 6694 1661 for a medical appointment if you have any concerns about your underlying medical conditions or if you get sick. Our clinic is a PHPC-accredited medical clinic. Under the MOH Swab & Go Home programme, our doctors can do a COVID-19 PCR Swab test if you meet the MOH medical crtieria.

Vitamins & Nutrients for a Well-functioning Immune System to Protect against COVID-19 & other Viral Infections

(Ref: Nutrients. 2020 Apr 23;12(4). pii: E1181. doi: 10.3390/nu12041181 Optimal Nutritional Status for a Well-Functioning Immune System Is an Important Factor to Protect against Viral Infections Calder PC¹, Carr AC², Gombart AF³, Eggersdorfer M⁴.

Iron-rich foods for Low blood haemoglobin

Healthy Diets for Optimal Health

The Anti - Inflammatory Diet

- Go Gluten-free

The Anti-Cancer Diet

- The Ketogenic Diet

Grow New Brain Cells

- The Neurogenesis Diet

Immune System Boosting, Anti-aging Longevity Diet

Groups at Higher Risk for Severe Illness in a COVID-19 Infection

Comorbidities & Underlying Health Conditions in COVID-19 Patients with Complications

高血压
糖尿病
脑血管疾病
心血管疾病
慢性肺部疾病
慢性肾病
哮喘
失智
慢性神经系统疾病
癌症
风湿病
肥胖
抽烟
慢性血液系统疾病/血红蛋白血液疾病
肝病/乙型肝炎感染
营养不良
免疫缺陷/免疫功能低下，例如 HIV AIDS
65岁及以上的人

(Ref: https://www.nature.com/articles/s41430-020-0642-3.pdf, Dailymail.co.uk, https://pubmed.ncbi.nlm.nih.gov/32320003/, Comorbidity and its impact on 1590 patients with Covid-19 in China: A Nationwide Analysis https://erj.ersjournals.com/content/early/2020/03/17/13993003.00547-2020

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The information provided in this website is for knowledge purposes only. It does not constitute medical advice.

Should you encounter any medical problem that you are unsure of, always consult your doctor or health care provider for assistance and medical advice.

MD International Medical Centre / MD International (Singapore) Pte Ltd

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MDIMC Medical Team

Together, Being here for you.

Doing Our Best in the COVID-19 Pandemic!

“Do all the good you can,
By all the means you can,
In all the ways you can,
In all the places you can,
At all the times you can,
To all the people you can,
As long as ever you can.”
― John Wesley