What do we mean by combination vaccines?

What is its role in creating greater immunity against the emerging corona virus "Covid-19"? And what is the role of natural immunity in preventing corona? And what is the "E484K" mutation of the Corona virus that frightens scientists? And what are the most prominent effects of Covid-19 on adolescents? ?The answers are in this comprehensive report.

We start in Germany, where a study indicated that a combination of Pfizer-BioNTech and AstraZeneca-Oxford vaccines may lead to more immunity boosting than relying on just one vaccine.

And researchers at Saarland University in western Germany discovered that people who received the first dose of the AstraZeneca vaccine and the second dose of the Pfizer-Biontech vaccine had stronger immunity than those who received the two doses of one particular vaccine, according to a report published by Deutsche Welle.

The findings of the University of Saarland are preliminary, as they have not been fully scientifically evaluated, which the university indicated in a press release regarding the study.

Before the results are officially announced, researchers at the University of Saarland intend to consider factors such as age and gender, and also, for example, study what combination vaccines may lead to dangerous side effects.

The team that conducted the study expressed its surprise at its results, although the full evaluation of its conclusions has not been completed yet.

This is why we "want to share our findings now rather than wait for the scientific evaluation process to be completed," said Martina Sester, professor of transplantation and infectious immunology at Saarland University.

 Antibody growth

250 people participated in the experiments conducted at the University Hospital in Saarland during the past few months, some of them received two doses of the AstraZeneca vaccine, others received the two doses of the Pfizer-Biontech vaccine, while the third group received a dose of AstraZeneca and then the second dose of Pfizer- Bionic.

The researchers compared the strength of the immune response to the participants in the trial two weeks after they received the second dose of vaccines.

"We looked not only at the numbers of antibodies against the Corona virus that developed inside the participants' bodies, but also at the effectiveness of the so-called neutralizing antibodies," Sister explained.

"This tells us how well these antibodies can prevent the virus from getting into our cells," she added.

With regard to antibody development, vaccination with two doses of Pfizer and the combination of AstraZeneca and Pfizer have been shown to be significantly more effective than vaccination with two doses of AstraZeneca alone.

The study revealed that people who received a mixed vaccine produced dozens of times more antibodies than people who received the two doses of AstraZeneca vaccine.

Seester said that given the neutralizing antibodies, the results of giving a mixture of two identical vaccines were "a little better" than even giving two doses of the Biotech vaccine.

It is noteworthy that the health authorities recommend taking the second dose of the same vaccine as the first dose.

Mixed vaccination not yet recommended

Although the initial results are promising, the World Health Organization still recommends not to confuse vaccines against the Corona virus.

Global Health spokeswoman Margaret Harris said there is not yet enough data to assess and conclude whether this combination vaccine approach is safe for health.

 What is the role of natural immunity in preventing corona?

Studies have shown that natural immunity is highly prevalent, and lasts for a long time.

If you have previously been infected with the Corona virus, one dose of the vaccine is sufficient for you.

Professor Marty McCurry, in a report published by the American Wall Street Journal, said that the news about the epidemic in the United States looks better than ever, as about 80% to 85% of American adults have immunity to the virus. The virus, as 64% of them received at least one dose of the vaccine, and of those who have not yet been vaccinated, about half of them have natural immunity because of their previous infection.

The writer added that there is strong and abundant scientific evidence on the effectiveness and continuity of natural immunity, and therefore health officials in countries of the world should pay attention to this issue.

Only about 10% of Americans have tested positive for the coronavirus, but 4 or 6 times more may have contracted it.

And a scientific study published last February in the journal Nature and based on examining antibodies in the population in late last summer, indicated that the real number of infected people was 7 times the number of those who underwent an official test with a positive result.

A similar study was conducted in the Department of Public Health in New York, which included only the first month of the outbreak, and showed that 23% of the city's population carry antibodies, a percentage that has certainly increased over time.

The writer stated that the contribution of natural immunity should be exploited to accelerate the return to normal life.

Since more than 80% of adults are protected against infection or transmission of the virus, corona likely will not spread through person-to-person transmission.

In the field of public health, the writer added, this is called herd immunity, a concept defined as "when the majority of the population is immune. It does not mean eliminating the virus but that it is an effective weapon."

With regard to the question about the need for previous patients to be vaccinated, this writer and doctor consider that the best advice for patients who are in good health and natural immunity is that one dose of the vaccine is sufficient, and even that dose may not be necessary, although it may enhance the duration of immunity in the long run.

This is of course the author's opinion, but to make the right decision for you, consult your doctor and the health authorities in your country.

 E484K mutation

In his article published by the French newspaper "Le Parisien", Nicolas Peraud mentions that while all eyes are focused on the "delta" strain of the Corona virus that appeared in India, some other strains broadcast the same amount of terror, in particular. Strains that carry the E484K mutation.

There are 10 worrying mutated strains. Three of them - the beta strain discovered in South Africa, the gamma strain discovered in Brazil, and the British alpha strain that acquired the famous E484K mutation - were rated as worrying.

Note that the list does not include the "Delta" strain that was discovered in India.

The author shows that "E484K", which is the name given to this mutation, means that the amino acid number 484 of the spike protein of the virus has changed when the virus multiplies.

Commenting on this, the French Public Health reported that it is following this spread with caution, because "E484K" can reduce the effectiveness of vaccines in the event of infection with one of the mutated strains.

Moreover, people who were previously infected with the Corona virus are not immune to infection with mutated strains, as was proven by re-infection with the “beta” or “gamma” strain, which was recorded at the beginning of this year.

Ravi Gupta, professor of clinical microbiology at the University of Cambridge, said the mutation was "the most worrying".

Currently, French Public Health and the Institut Pasteur Reference Center for Respiratory Diseases have said after their latest risk analysis that several laboratory data raise concerns about reduced efficacy of vaccines or post-infection immunity.

The writer quoted Stefan Corcia Meffer, the medical editor of the newspaper "Vidal", that "it is clear that this is the only mutation capable of causing relative resistance to immunity without harming the virus, either by reducing infection or by impairing its ability to reproduce."

What are the most prominent ongoing effects of COVID-19 among adolescents?

Several months after contracting COVID-19, teens complain of persistent symptoms of fatigue, difficulty concentrating, and dizziness.

In the report published by the French newspaper "la-croix", the writer Jean Vernay quoted Dr. Alaa Ghaly - one of the specialists in chronic fatigue syndrome whose manifestations are similar to the symptoms of Covid-19 disease, and this doctor works at the University Hospital of Angers - that Note that some symptoms return regularly, particularly intolerance to standing and fatigue after exercise.

Ghali summarized his speech by saying that "the physical or psychological effort that they made before has become impossible."

On the other hand, Ghaly stated that "the persistence of these problems can lead to psychological problems, as the parents' fears, which are often very strong, affect their morale."

Sometimes these teens and their families just need to be heard.

"For them, it's a relief," said Dr. Anne Perrin, a pediatrician in the Adolescent Unit at University Hospitals in Geneva, Switzerland.

Perrin co-created a counseling group a few weeks ago dedicated to pediatric patients with COVID-19.

"Currently, we've had about 20 patients. It's clear that these problems don't concern most teens, they are far from it. Just because there is a lack of data doesn't mean you shouldn't try to help them. Some teens are severely disabled because of these symptoms, which often have a significant impact on their education."

Keywords: