CMAAO Coronavirus Facts and Myth Buster: Pfizer Vaccine

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With input from Dr Monica Vasudev

1144: Pfizer Vaccine Data Show 90% Efficacy in Early Results

An interim analysis of a phase 3 study has shown that a vaccine candidate against SARS-CoV-2 is 90% effective in preventing COVID-19 in trial volunteers who did not have evidence of prior infection of the virus.

BTN162b2 is a messenger RNA–based vaccine candidate that requires two doses. It is being developed by Pfizer and BioNTech SE. A phase 3 clinical trial of BTN162b2 was started on July 27 and has recruited 43,538 participants as of date; 42% of the participants have racially and ethnically diverse backgrounds.

In all, 38,955 volunteers had received a second dose of either vaccine or placebo as of November 8. An interim analysis of 94 individuals by an independent data monitoring committee (DMC) noted the vaccine efficacy rate to be more than 90% seven days after the second dose. Protection was thus achieved 28 days after the first dose.

The results validate the genetic strategy, whether its mRNA vaccines or DNA vaccines.

All of these have the same approach. The gene that codes for the coronavirus spike protein is introduced into the cell. Our cell makes the spike protein, and our immune system produces antibodies to the spike protein. In these preliminary data involving 94 people getting sick, it appears to be effective.

As per Pfizer and BioNTech SE, a final data analysis will be done once 164 confirmed COVID-19 cases have accrued. The DMC has not reported any serious safety concerns. It has recommended that the study must continue to gather safety and efficacy data. The companies may apply to the FDA for emergency use authorization soon after the required safety milestone is achieved.

The company cannot apply for FDA Emergency Use Authorization based on these findings. More data on safety is also required. At least two months of safety data after the second dose of the vaccine candidate is required by FDAs guidance for potential Emergency Use Authorization. It will be available by the third week of November.

Administering the vaccine will be tricky. This vaccine needs to be shipped and stored at –70° C or –80° C, which most countries have not done before. This means that the product needs to be maintained on dry ice. [Medscape Excerpts]

mRNA are a whole new type of vaccine: It is first of its type. This is a unique way of making a vaccine and no such vaccine has thus far received license for an infectious disease. Vaccines train the body to recognize and respond to the proteins produced by disease-causing pathogens. Traditional vaccines involve small or inactivated doses of the whole pathogen, or the proteins that it produces,which are introduced into the body to incite the immune system to evoke a response.
mRNA vaccines trick the body into producing some of the viral proteins itself. They use mRNA, or messenger RNA, the molecule that puts DNA instructions into action. Inside a cell, mRNA works as a template to build a protein. An mRNA is like a pre-form of a protein and its sequence encodes what the protein is made of later on.

To develop an mRNA vaccine, a synthetic version of the mRNA that a virus uses to build its infectious proteins, is produced. The mRNA is delivered into the body, and the cells read it as instructions to build that viral protein, thus creating some of the virus’s molecules themselves. These proteins are solitary, and do not accumulate to form a virus. The immune system then detects these viral proteins and starts producing a defensive response to them.

They could be more potent to produce than traditional vaccines
Our immune system has two parts – innate and acquired. Classical vaccine molecules usually work with the acquired immune system and the innate system is activated by another ingredient, called an adjuvant. The mRNA in vaccines could also trigger the innate immune system, thus providing an additional layer of defence without the need to add adjuvants.

All kinds of innate immune cells are activated by the mRNA. The type of immune response thus triggered is very strong.

Since the whole virus is not introduced into the body, the virus can’t mount its own self-defence and the immune system can therefore create a response to the viral proteins without interference by the virus.

As the human body produces the viral proteins itself, mRNA vaccines cut out some of the manufacturing process and should be easier and quicker to produce than traditional vaccines.

Most of our information about mRNA vaccines comes from work on cancer
Most work on using mRNA to incite an immune response has primarily focused on cancer, with tumor mRNA being used to help people’s immune systems recognize and respond to the proteins produced by their specific tumours.

Using tumor mRNA this way tends to activate the body’s T-cells, a part of the acquired immune system. It could be important for coronavirus as well. In viral infections, there is a need for a strong T-cell response because viruses like to hide in cells.

To fight a virus like SARS-CoV-2, a different part of the acquired immune system might also need to be activated, which is the B cells. These produce antibodies that mark the virus out for destruction by the body.

The unknowns
Some outstanding questions include if the proteins chosen for the vaccine are the right ones to prevent a coronavirus infection in the body, how targeted the immune response is to this particular virus, how long an immunity would last, and whether it causes side-effects like increased inflammatory responses like redness and swelling or, in the worst case, aggravates disease.

Possibility to vaccinate on large scale.
The manufacturing process is shorter in comparison with other vaccines. It is possible for these vaccines to be scaled up quickly.

[Excerpts from]

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA

CMAAO Coronavirus Facts and Myth Buster: Current status of COVID-19 in CMAAO countries

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With input from Dr Monica Vasudev

1107 Minutes of Virtual Meeting of CMAAO NMAs on “Current status of COVID-19 in CMAAO countries: NMA Presentation”

10th October, 2020, Saturday, 9.30am-10.30am

Participants: Member NMAs

Dr KK Aggarwal, President CMAAO; Dr Yeh Woei Chong, Singapore, Chair CMAAO; Dr Alvin Yee-Shing Chan, Hong Kong, Treasurer, CMAAO; Dr Marie Uzawa Urabe, Japan; Dr Ravi Naidu, Malaysia’; Dr Md Jamaluddin Chowdhury, Bangladesh; Dr SM Qaisar Sajjad, Secretary General, Pakistan Medical Association

Invitees: Dr S Sharma, Editor IJCP Group

Key points from the discussion

Discussion point #1: Analyzing President Trump’s illness

President Trump’s illness has raised issues about diagnosis, treatment and public health aspects.
A 14-day quarantine period is required for close contacts and 10 days isolation for confirmed cases. But isolation and quarantine rules were not followed.
During the debate, Vice President Mike Pence was seen with left eye redness. Did he have COVID conjunctivitis? He has not been tested so far.
President Trump was out of hospital prematurely, within 3 days. The President should have had two consecutive negative specimens 24 hours apart and only then return to office. He removed his mask and put it in his pocket (his doctor-in-charge also did the same in his press conference); he entered a room and had a meeting with people who were not wearing a mask.
Around 12 people in the White House have developed COVID-19; this shows lack of protocol regarding screening and testing.
President Trump received a cocktail of vitamin D, zinc, remdesivir (this means that he had hypoxia), steroids (he had high CRP or high IL-6), famotidine, statin and monoclonal antibodies. He did not receive HCQ, which he had earlier been advocating.
Discussion point #2: Current status of COVID-19 in CMAAO countries

Bangladesh Update: The number of new cases daily is around 1400; the number of deaths is decreasing to less than 20. The government is advocating use of mask, but less than 50% of people use masks. This has been continuing for a month. The government should intervene and impose a law regarding wearing of mask. People do not want to get themselves tested.
Hong Kong Update: Hong Kong is now on the verge of a fourth wave. Since one week, everyday some cases are positive (but in single digits) with unknown origin. This is detrimental to the plans to recover the economy. One cluster has been detected in bars, which opened one week ago. The HK Medical Association is drafting a letter to the government urging them for more stringent regulation of bars. And to not allow exemption for testing of people who cross borders. There is a need to have much more proactive vigilance in detecting the source of infection.
Malaysia Update: Government has enforced law on face masks and social distancing. One is required to register name and phone number upon entering any mall, shop, dining place, etc., for contact tracing.Many new cases were detected following bye-election in the state of Sabah. There were 375 new cases yesterday (9th Oct); there have been 11 deaths in the last 2 days. 20 patients are on ventilators and 60 are in ICUs. Probably this is the third wave. Many new clusters are being formed. The government has imposed restricted lockdown in areas where clusters are detected and not the whole country.
Pakistan Update: The numbers have again started increasing from the end of September. Today, according to government figures, there have been 692 new cases. Numbers are higher in Sindh province compared to other parts of the country. Six deaths have been recorded in 24 hours. Majority of people are not following precautions. This is alarming as cases may increase and the load on hospitals and HCWs may also increase.
Japan Update: The first and second waves have been compared in a registry study. There is a reduction in mortality and/or hospitalization in every generation. There were no deaths in patients under the age of 69 years.
Singapore Update: The dormitory outbreak is under control. Yesterday, there were 10 new cases – one in a dormitory and 9 imported cases; no new cases in the community. Migrant workers have been allowed to resume work but all of them are being swabbed every 2 weeks. The total number of cases is around 58,000; of these 56,000 are in migrant workers and 2000 are community cases. Singapore is trying to open travel (cruise ships, air travel bubble).

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA

IMA-CMAAO Webinar on “Eye Manifestations and COVID-19″

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26th September, 2020, 4-5pm

Participants: Dr KK Aggarwal, President CMAAO; Dr RV Asokan, Hony Secretary General IMA; Dr Ramesh K Datta, Hony Finance Secretary IMA; Dr Jayakrishnan Alapet; Dr VK Goel, Dr RS Hazuria; Dr S Sharma

Faculty: Dr AK Grover, Chairman, Dept. of Ophthalmology, Sir Ganga Ram Hospital, Chairman, Vision Eye Centres, Siri Fort Road and West Patel Nagar, New Delhi

Key points from the discussion

  • Left eye conjunctivitis is most common in COVID-19.
  • VP Mike Pence, USA, was seen with left eye involvement ?COVID-19
  • Transmission can occur through the ocular surface or aerosol contact with the conjunctiva. Hence, eye protection is an integral component of the protective measures to be taken by a person taking care of a person with COVID.
  • Conjunctivitis may be the first presenting symptom. Conjunctival congestion has also been observed in confirmed cases of infection.
  • There are anecdotal reports of vascular occlusion and immune phenomenon occurring in the orbit and other structures of the eye. But these have not yet been documented significantly.
  • The risk of transmission in ophthalmology is very real because of the proximity in examination and treatment procedures. The concentration on the surface of the eye may not be so high and the ACE2 receptors here may not be as dense as in the lungs, so there should not be paranoia. Follow all screening protocols, have a good system of triage and follow hygiene measures to prevent risk of transmission. Eye protection should be used by clinicians to avoid transmission through the surface.
  • Studies have shown that the virus is present in tears of patients (moderate to severe cases); may also be present in asymptomatic persons.
  • A landmark study from India has demonstrated the virus in tears of 24% of patients with lab proven moderate to severe COVID-19 by conjunctival swab (RT PCR). This indicates a high possibility of transmission of the virus through tears in these patients.
  • COVID-19 has had a severe impact on day-to-day work.
  • COVID-19 and the lockdown that followed have affected patient care. A study from Aravind Eye hospital, Madurai, done from March 25-May 3 showed that OPD visits and retinal laser procedures have decreased by 96.5%; sight saving intravitreal injections decreased by 98% and cataract surgeries decreased by 99.7%.
  • Very few corneal grafts were being done during this period, resulting in vision loss. Patients with open globe injuries underwent evisceration as they presented late.
  • Emergency procedures could not be done due to logistic reasons.
  • Community eye care also suffered – no screening camps, no community surgery, eye donations decreased, peripheral vision centers in rural areas were not functioning.
  • COVID-19 has greatly affected residency education (theoretical, clinical and surgical); specially designed webinars for PG training have now started.
  • COVID-19 has had an impact on day-to-day eye care practices. Most eye care is provided by stand-alone hospitals and most work is elective. The work is now picking up but is still around 50-60%. There was huge impact on turnover; at one point it was close to zero percent. Survival plans had to be worked on. Getting back after lockdown requires lot of modifications.
  • A RT PCR test report (of last 48 hours) is must for all longer procedures; test is also advised for shorter procedures like cataract, but there has been some resistance.

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA

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