জেনেটিক পরিবর্তনের ফলে করোনাভাইরাসের রোগসৃষ্টির ক্ষমতা কি কমছে?

Interview of Voice of America (VOA) with 

Dr Mustak Ibn Ayub, Department of Genetic Engineering and Biotechnology, University of Dhaka

CARES is committed to giving the society the right information about the COVD -19.  Only scientific discussions by practising scientists from Bangladesh and other places are in CARES website.  Here are some new insightful suggestions from Professor Dr Jeba Seraj, an active member of CARES and a life scientist at Dhaka University. At CARES we talk science.  Engage Science in your life.   –  Wali-ul-Maroof Matin, Chairman, CARES


Covid-19: Taming the beast

Professor Ahmed Abdullah Azad PhD, Secretary General, Islamic-World Academy of Sciences

The Covid-19 pandemic, caused by coronavirus SARS-CoV-2, has brought the entire world to its knees and virtually stopped all face-to-face social interactions between humans. Personal freedoms and human rights have been severely curtailed all over the world to help slow down the infection and death rates. This newly discovered coronavirus is extremely contagious, and up to 20 times more deadly than seasonal flu. Currently, the only way to reduce community spread is by maintaining good hygiene, social distance and self-isolation. In Bangladesh, it will be a challenge to implement these public health measures in congested environments, and particularly hard for disadvantaged people and casual workers who would starve if confined at home for long. A substantial portion of the government’s stimulation package must be ring-fenced for the poor and needy, otherwise the public health measures will fail.

Effective health and economic policies to counter the adverse effects of the pandemic require extensive testing for the presence of the virus in infected individuals, and people they have been in contact with. PCR- and sequence-based tests require expensive equipment and reagents, are time-consuming, and the total capacity is hardly adequate for testing all infected individuals, contact tracing and determining the infection status of health care workers. There is an urgent need for a quick, inexpensive and less-invasive blood tests for detecting anti-viral antibodies and confirming infection. A simple dot-blot blood test that provides results within 15 minutes has reportedly been developed through a joint venture collaboration between Gonoshasthaya Kendra and RNA Biotech Ltd, a company formed by a group of young researchers in Bangladesh.

If the claims for this locally developed test are validated, then the project should be treated and supported as an urgent national priority, so that adequate numbers of kits can be made available for extensive testing at the earliest. The quoted price per test is miniscule in comparison to the gene-based assays currently in use in Bangladesh and could be much lower if the recombinant antigens (the four structural proteins of the virus) were produced in Bangladesh. The imported recombinant viral antigens, produced in bacteria (E.coli), might suffice for virus detection but may not be ideal for further biological and clinical studies.

CARES is committed to giving the society the right information about the COVID -19.  Only scientific discussions by practising scientists from Bangladesh and other places are in CARES website.  Here are some new insightful suggestions from Professor Dr Jeba Seraj, an active member of CARES and a life scientist at Dhaka University. At CARES we talk science.  Engage Science in your life.   –  Wali-ul-Maroof Matin, Chairman, CARES

The above rapid test, using locally-produced recombinant antigens that more closely resemble those in the virus particle, could also be an important research tool for following antibody production and response during different phases of disease progression. If properly designed, the dot-blot assay could help identify virus-neutralising antibody in blood collected from individuals recovered from the infection. If the neutralising antibody could be purified, then its protein sequence could be reverse-engineered into a therapeutic monoclonal antibody for mass production by recombinant DNA technology. The required expertise is present in Bangladesh but the multidisciplinary technologies need to be assembled under one roof as a national core facility, a plea that has fallen on deaf ears.

It is not enough to just keep the virus at bay by social isolation. The virus-induced paralysis of normal life and enforced shutdown cannot continue ad infinitum, and countermeasures need to be contemplated. To tame and conquer the invisible beast, we need to understand its biology and molecular structure to discover its soft underbelly as a target for drug and vaccine development. Coronaviruses of innumerable types are ubiquitous in many non-primate animals. Seven of these have managed to cross over into humans. Four have been around for over a century, and cause about a third of all the seasonal colds. Three that have emerged in recent years (SARS, MERS and Covid-19) cause severe illness in humans, termed Acute Respiratory Distress Syndrome (ARDS), but SARS-CoV-2 (Covid-19 virus) is by far the most deadly and contagious.

So, how did SARS-CoV-2 emerge in humans and why is it so dangerous? The ancestor could be a bat coronavirus (88 percent sequence homology) that cannot produce disease in humans or spread from one human to another. It could have picked up these properties through genetic exchange with another coronavirus in a co-infected intermediate host such as a pangolin (an ant-eating mammal), which is a culinary delicacy and is used in Chinese medicine. It is possible that the Covid-19 virus that had finally evolved into a dangerous pathogen in pangolins passed over into a human in the wet markets of Wuhan. SARS-CoV-2 can enter human cells and spread to other humans through a molecular interplay between the viral spike protein on its surface (that gives all coronaviruses the spectacular crown-like appearance) and two vital enzymes on the surface of human cells.

The spike protein of the SARS-CoV-2 virus contains two distinct structural units. A receptor-binding domain uses a human enzyme—angiotensin converting enzyme 2 (ACE 2),as a receptor to attach the virus to the human cell surface. A second membrane-binding domain, after specific cleavage by the human enzyme Furin, can interact with and fuse the virus and cell membranes, thus facilitating virus entry into epithelial cells, and then into lung cells.This leads to infection of both the upper and lower respiratory tracts (lungs) causing ARDS, which is characterised by serious breathlessness, breakdown of cell signalling networks (cytokine storm), self-destructive immune response and massive secondary infections, ultimately leading to multiple organ failure, especially in older people with co-morbidities such as heart disease, hypertension, diabetes, kidney disease and immunodeficiencies. Less virulent and less contagious human coronaviruses either do not contain the Furin-cleavage site or possess a partial Furin-cleavage site.

Two therapeutic approaches can be tried to stop SARS-CoV-2 from infecting humans. One is to prevent or disrupt the interaction between ACE 2 and the receptor-binding domain of the viral spike protein. The other is to prevent Furin from cleaving the viral spike protein. While required expertise and facilities in structural biology and rational drug design may not be currently available, scientists in Bangladesh can target the above drug development opportunities by using expertise and resources already available to them. Molecular and cell biologists should be able to develop very specific bioassays based on the above molecular targets, and these disease-specific bioassays could be used to screen the very large libraries of indigenous medicinal plants, and isolated secondary metabolites, collected by ethnobiologists and medicinal chemists in Bangladesh. Every positive lead compound would be a potential candidate drug against SARS-CoV-2 that could be patented and developed into a new drug if the required technology platform is established as a national core facility, another plea that has gone unheeded over the last fifteen years. Hopefully, the Covid-19 pandemic will open the eyes and ears of our policymakers so that higher education, research and innovation are supported at the required levels, so that we are prepared the next time around.

Besides coronaviruses, a number of viruses have crossed over from wild animals to humans (Influenza, HIV, Ebola, Marburg) in recent years, causing very frightful diseases. Most of them have lived in animal hosts for thousands of years but in recent times, human activities have destroyed the natural habitats of their hosts and brought man and wild animals into close contact. The Covid-19 pandemic is a timely warning to the human race to not destroy the environment and natural habitats of exotic animals in the mad pursuit of profits and development at any cost.

Prof Ahmed Azad PhD, a retired molecular virologist, has been intimately involved in developing several anti-viral drugs and vaccines. After retirement (2006), he has worked with younger colleagues to help build biotechnology research capacity in Bangladesh. Email:

The writer is a founding member of CARES.


What to do if you develop Coronavirus (Covid-19) Symptoms

If you or your neighbour/relative has cough, fever, throat pain or running nose, please do the following things frequently & regularly. Even if you don’t have those symptoms, you can follow these for prevention:

  1. Worm water with salt gargle several times a day
  2. Hot steam/vapour inhalation through nose & mouth at least 2-3 times daily
  3. Drink hot water with lemon several times daily
  4. Take ginger tea more (green tea better)
  5. Take more orange & malta daily
  6. Take some black seeds (kali jira) 2-3 times daily
  7. Take rice or bread as less as possible, avoid meat, take well-cooked fish, egg & chicken (occasional), drink milk (skimmed or fat-free)
  8. Take any type of fruits more (after washing thoroughly). Preferable fruits: orange, banana (diabetics should take less), pomegranate (anar), apple, kiwi etc,
  9. Eat all sorts of well-cooked or boiled vegetables. Preferable vegetables: tomatoes, carrots, capsicum, cauliflower, broccoli, cabbage, spinach, beans, lentils, legumes etc.
  10. For fever & pain, take Paracetamol tablet only (after food). For running nose or nose-block, take antihistamine only (ceitrizine/loratidine). For dry cough, take natural cough syrup or antitussive syrup only. For productive cough with sputum, take spectorant/mucolytic syrup only. (for appropriate drug & dose, better to consult with a registered doctor), and finally
  11. If you develop any sort of breathing difficulty/respiratory distress with the above symptoms, please immediately call the local control centre of health or call an ambulance to take you to any of the designated/assigned hospitals. Please don’t delay in case of breathing difficulty with fever & cough.

Thank you all….Stay home, stay safe & stay healthy……May Almighty protect all of us.

Writer:  Dr Mohammad Dewan, Ministry of Health, Saudi Arabia (Madinah Munawara)

COVID-19 Vaccine

(Compiled by Dr. Md. Mozammel Hoq)

As the new coronavirus continues to spread, people around the world are anxious to know when we might have a vaccine to stop it.

What Would a COVID-19 Vaccine Do?

When you come into contact with a virus or bacteria, your body’s immune system makes antibodies to fight them off.

A vaccine forces your immune system to make antibodies against a specific disease, usually with a dead or weakened form of the germs. Then, if you come into contact with them again, your immune system knows what to do. The vaccine gives you immunity, so you don’t get sick or so your illness is much milder than it otherwise would have been.

A vaccine against COVID-19 would slow its spread around the world. Fewer people would get sick, and more lives could be saved.

How Are Vaccines Developed?

So how long could a COVID-19 vaccine take? Dozens of possible vaccines are in various stages of development around the world, according to the World Health Organization. Some have begun clinical trials. But certain things can’t be rushed, like how long it takes a person’s immune system to respond to a vaccine or the wait to check for side effects.

Even when researchers find a vaccine that works against the new coronavirus, it could be 12 to 18 months at best before it’s ready for the public. That’s only a fraction of the usual time.

Before any vaccine can be used widely, it must go through development and testing to make sure that it’s effective against the virus or bacteria and that it doesn’t cause other problems. The stages of development generally follow this timeline:

  • Exploratory stage. This is the start of lab research to find something that can treat or prevent a disease. It often lasts 2 to 4 years.
  • Pre-clinical stage. Scientists use lab tests and testing in animals, such as mice or monkeys, to learn whether a vaccine might work. This stage usually lasts 1 to 2 years. Many potential vaccines don’t make it past this point. But if the tests are successful and the FDA signs off, it’s on to clinical testing.
  • Clinical development. This is a three-phase process of testing in humans. Phase I usually lasts 1 to 2 years and involves fewer than 100 people. Phase II takes at least 2 years and includes several hundred people. Phase III lasts 3 or 4 years and involves thousands of people. Overall, the clinical trial process may stretch to 15 years or more. About a third of vaccines make it from phase I to final approval.
  • Regulatory review and approval. Scientists with the FDA and CDC go over the data from the clinical trials and sign off.
  • Manufacturing. The vaccine goes into production. The FDA inspects the factory and approves drug labels.
  • Quality control. Scientists and government agencies keep tabs on the drug-making process and on people who get the vaccine. They want to make sure it keeps working safely.

This version of the coronavirus only surfaced in late 2019, but scientists have gotten a boost from research on similar coronaviruses that cause severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). Efforts to fight those diseases played a large role in the record speed of the first COVID-19 vaccine trial that’s now underway.

Some of the companies working on vaccines are also looking for ways to ramp up production quickly when the clinical trials find one that works safely. With more than 300 million people in the United States alone, mass vaccination will be a joint effort among several companies and government agencies.

Experts say the coronavirus could turn out to be seasonal, like colds and the flu. A vaccine might not be ready until after the current pandemic is over, but it may be vital if the cycle begins again.

(WebMD Medical Reference Reviewed on April 03, 2020)

Combat Coronavirus (Covid-19) Pandemic

Know Covid-19 (Novel Coronavirus) through question and answers and be safe.

Q.  What Is COVID-19?

Coronavirus disease 2019, or COVID-19, is a disease that can cause what doctors call a respiratory tract infection. It can affect your upper respiratory tract (sinuses, nose, and throat) or lower respiratory tract (windpipe and lungs).
The COVID-19 outbreak quickly spread around the world. It spreads the same way other coronaviruses do, mainly through person-to-person contact. Infections range from mild to serious.
COVID-19 is one of seven types of coronavirus, including the ones that cause severe diseases like Middle East Respiratory Syndrome (MERS) and Sudden Acute Respiratory Syndrome (SARS). The other coronaviruses cause most of the colds that affect us during the year but aren’t a serious threat for otherwise healthy people.

Q.  What Are the Symptoms of COVID-19?

Early symptoms include:

> Fever
> Dry Cough
> Fatigue
The virus can lead to pneumonia, respiratory failure, septic shock, and death. If you notice these severe symptoms in yourself or a loved one, get medical attention right away:
> Trouble breathing or shortness of breath
> Ongoing chest pain or pressure
> New confusion
> Can’t wake up
> Bluish lips or face
If you’re exposed and infected, symptoms can show up in as few as 2 days or as many as 14. It varies from person to person
The most common symptoms and the percentage of people who have them include:
> Fever: 88%
> Dry cough: 68%
> Fatigue: 38%
> Coughing up sputum, or thick phlegm, from the lungs: 33%
> Shortness of breath: 19%
> Bone or joint pain: 15%
> Sore throat: 14%
> Headache: 14%
> Chills: 11%
> Nausea or vomiting: 5%
> Stuffy nose: 5%
> Diarrhea: 4%
> Coughing up blood: 1%
> Swollen eyes: 1%

Q.  How Do You Know if It’s COVID-19, a Cold, or the Flu?

When you have symptoms, they can be similar to a bad cold or the flu. Your doctor will suspect COVID-19 if:
> You have a fever and breathing problems and you’ve travelled to places where the virus has spread.
> You’ve been exposed to people who have it within the last 14 days.

Q.  Testing for COVID-19

Call your doctor or IEDCR (through hotlines) if you think you’ve been exposed and have symptoms like:
> Fever of 100 F or higher
> Cough
> Trouble breathing
In most states, decisions about who gets tested are made at the IEDCR or your doctor of the hospital you visit.
The test looks for evidence of the virus in your upper respiratory tract. The person giving the test puts a swab up your nose to get a sample from the back of your nose and throat. That sample goes to a lab that looks for viral material or the presence of antibody in the serum against COVID-19.

Q.  What Is the Treatment for COVID-19?

There’s no specific treatment for COVID-19. People who get a mild case need the care to ease their symptoms, like rest, fluids, and fever control. You can take medicine for a sore throat, body aches, and fever upon advice by a physician. But don’t give aspirin to children or teens younger than 19. You might have heard that you shouldn’t take ibuprofen to treat COVID-19 symptoms — the
WHO made that statement in March 2020. But they reversed it soon after and said there’s no proof that taking it causes any harm.
Antibiotics won’t help because they treat bacteria, not viruses. If you hear about people with COVID-19 getting antibiotics, it’s for an infection that came along with the disease.
Those with severe symptoms need to be cared for in the hospital.
Numerous clinical trials are underway to explore treatments used for other conditions that could fight COVID-19 and to develop new ones. Several studies are focused on an antiviral medication called remdesivir, which was first created to fight Ebola. A study in China showed that hydroxychloroquine and chloroquine, which are used to treat malaria and autoimmune conditions like rheumatoid arthritis and lupus, helped people with COVID-19 pneumonia.

Q.  Is There a Vaccine?

Not yet, but clinical trials are underway in the U.S. and in China to test vaccines for SARS-CoV-2/COVID-19.
One vaccine called mRNA-1273 (which was developed by using messenger RNA) would tell your cells to pump out a protein that will kick-start your immune system to fight the virus. It’s worked well in animals and is ready to test in humans.

Q.  What Is Community Spread?

IEDCR, Doctors and health officials use this term when they don’t know the source of the infection. With COVID-19, it usually refers to someone who gets the virus even though they haven’t been out of the country or haven’t been exposed to someone who’s travelled abroad or who has COVID-19.

Q.  How Do You Prevent the Spread?

If you’re in an area where it’s spreading, take these steps:
> Wash your hands often with soap and water or clean them with an alcohol-based sanitizer. This kills viruses on your hands.
> Practice social distancing. Because you can have and spread the virus without knowing it, you should stay at home as much as possible. If you do have to go out, stay at least 6 feet away from others.
> Don’t touch your face. Coronaviruses can live on surfaces you touch for several hours. If they get on your hands and you touch your eyes, nose, or mouth, they can get into your body.
> Clean and disinfect. You can clean first with soap and water, but disinfect surfaces you touch often, like tables, doorknobs, light switches, toilets, faucets, and sinks. Use a mix of household bleach and water (1/3 cup bleach per gallon of water, or 4 teaspoons bleach per quart of water) or a household cleaner that’s approved to treat SARS-CoV-

Q.  What Caused the New Coronavirus?

Doctors aren’t sure. Coronaviruses can affect different species of animals, in addition to people. MERS and SARS were both linked to animals. Studies show COVID-10 has ties to snakes, bats, and pangolins. Many people who got the disease early on were linked to a large live seafood and animal market in China — you might hear it called a “wet market.” The first cases may have come from animals sold in the market, then spread from person to person.

Q.  How Does the New Coronavirus Spread?

SARS-CoV-2, the virus, mainly spreads from person to person.
Most of the time, it spreads when a sick person coughs or sneezes. They can spray droplets as far as 6 feet away. If you breathe them in or swallow them, the virus can get into your body. Some people who have the virus don’t have symptoms, but they can still spread the virus.
You can also get the virus from touching a surface or object the virus is on, then touching your mouth, nose, or possibly your eyes. Most viruses can live for several hours on a surface that they land on. A study shows that the COVID-19 coronavirus can last for several hours on various types of surfaces:
> Copper: 4 hours
> Cardboard up to 24 hours
> Plastic or stainless steel: 2 to 3 days
That’s why it’s important to disinfect surfaces to get rid of the virus.

Q.  Is There More Than One Strain of SARS-CoV-2?

It’s normal for a virus to change, or mutate, as it infects people. A Chinese study of 103 COVID-19 cases suggests the virus that causes it has done just that. They found two strains, which they named L and S. The S type is older, but the L type was more common in the early stages of the outbreak. They think one may cause more cases of the disease than the other, but they’re still working on what it all means.

Q.  Are Coronaviruses New?

Coronaviruses were first identified in the 1960s, but we don’t know where they come from.
Almost everyone gets a coronavirus infection at least once in their life, most likely as a young child. In our country Bangladesh, throughout the year especially during seasons change, typical flue attack many people but treatment and recording are not maintained. In the United States, regular coronaviruses are more common in the fall and winter, but anyone can come down with a coronavirus infection at any time.
The symptoms of most coronaviruses are similar to any other upper respiratory infection, including a runny nose, coughing, sore throat, and sometimes a fever. In most cases, you won’t know whether you have a coronavirus or a different cold-causing virus, such as rhinovirus. You treat this kind of coronavirus infection the same way you treat a cold.

Q.  Have There Been Other Serious Outbreaks?

Yes, coronaviruses have led to two serious outbreaks:
Middle East Respiratory Syndrome (MERS): About 858 people have died from MERS, which first appeared in Saudi Arabia and then in other countries in the Middle East, Africa, Asia, and Europe. In April 2014, the first American was hospitalized for MERS in Indiana, and another case was reported in Florida. Both had just returned from Saudi Arabia. In May 2015, there was an outbreak of MERS in South Korea, which was the largest outbreak outside of the Arabian Peninsula.
Severe acute respiratory syndrome ( SARS ): In 2003, 774 people died from an outbreak. As of 2015, there were no further reports of cases of SARS.

For any query:
General Secretary, CARES
Dr, Md. Mozammel Hoq, Professor (Retired)
Department of Microbiology, University of Dhaka