Microbiology Independent Research Journal (MIR Journal)

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MIR Journal Impact Factor

According to Russian Science Citation Index (RSCI), the two-year impact factor of MIR Journal (ISSN: 2500-2236) in 2020 was 0.842, ranking MIR Journal as 45th out of 205 Russian science journals specializing in biology (


Study Suggests Lasting Immunity to Virus Variants After Recovery from Covid-19 and Vaccination

By Victor Zhivich

А paper published by Michel Nussenzweig et al. in Nature on the 14th of June 2021 [1] describes the study of long-term immunity to the virus SARS-CoV-2 and its new variants in patients that previously had COVID-19. Researchers examined 149 patients who recovered from COVID-19 in 6 and 12 months from symptoms development. From these patients 41% were vaccinated with Moderna (mRNA-1273) or Pfizer-BioNTech (BNT162b2) vaccines within 40 days interval before the 12-month time point. Antibodies to the virus were measured in their plasma samples. Both vaccinated and unvaccinated patients had plasma neutralizing antibodies to the receptor binding domain (RBD) of spike protein of SARS-CoV-2 virus at 6- and 12-months time points. Additionally, patients reported experiencing less symptoms as time went on, with 44% of patients at 6 months, whereas only 14% experienced any symptoms at 12 months. While previously infected patients have lasting plasma antibodies with neutralizing activity to the spike protein, patients that were not vaccinated had less neutralizing antibodies against variants compared to vaccinated patients. 88% of unvaccinated patients had neutralizing antibodies to the virus variant they previously were infected with, however, only 47% had neutralizing activity to the delta variant, a rapidly spreading variant of the virus. This suggests that unvaccinated previously recovered from COVID-19 patients have a fifty-fifty chance of being infected by the new virus variant. Antibodies in previously recovered from COVID-19 vaccinated individuals showed higher binding with virus RBD as well as a 50-fold increase in neutralizing activity.


Six fully vaccinated people were infected with the Delta variant of SARS-CoV-2 virus

By Alexander Zhivich

According to the report in Forbes magazine (based on an article preprint in medRxiv), six people tested positive for SARS-CoV-2 after attending a 92-person wedding in Texas in April.

As a precaution, the gathering was held under a large open-air tent and all guests were fully vaccinated. After the wedding, six people – three men and three women 53-69 years old – were tested positive for SARS-CoV-2. A man and a woman who were recently traveling from India got sick first. They had received two shots of Covaxin BBV152 vaccine before leaving India. Both of them tested positive 4 days after the wedding; the man was hospitalized and died 2 days later. Another 4 people who interacted with them at the wedding also tested positive for SARS-CoV-2. Two of them had Pfizer/BioNTech vaccine and the other two Moderna vaccine. One man was hospitalized. The viral sequencing confirmed that the transferred virus was the Delta variant. Based on these data, scientists suggest that there are true cases of vaccines breakthrough by the Delta variant of the virus. Therefore, as Forbes concluded: “While the available COVID-19 vaccines can offer good protection against SARS-Cov-2, the protection is not perfect. As long as the pandemic is continuing, it is better to maintain multiple layers of SARS-CoV-2 precautions when you can”.


Are the existing vaccines efficient against new mutant variants of SARS-CoV-2?

By Victor Zhivich

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic started in 2019 has spread all over the world causing millions of deaths and over 150 million infections. Over the course of the pandemic, the virus has accumulated different mutations, forming new strains of the virus that have emerged from different countries. Some of these strains are more contagious. The mutations in the viral spike protein play a key role in the virus binding to the cell receptor – angiotensin-converting enzyme 2 (ACE 2) – and consequently on the virus transmission and disease outcome in general. As the existing vaccines were developed with the use of the original strain of SARS-CoV-2 isolated in Wuhan (USA-WA1/2020), there was a concern that these vaccines may not offer protection against the new variants. Scientists tested the BNT162b2 mRNA Covid-19 vaccine’s efficacy (produced by Pfizer-BioNTech) against the different virus variants by using the sera of people who received this vaccine [1]. The sera were incubated with the recombinant strains with spike proteins of viruses B.1.617.1, B.1.617.2, B.1.618 (identified in India) or B.1.525 (identified in Nigeria), and the inhibition of the virus was measured. The patient’s sera were found to inhibit all recombinant strains with mutant spike proteins in the plaque reduction neutralization assay (PRNT) as shown in Fig. 1. The lowest titer was shown for the B.1.617.1 variant (from India). This proves that the vaccine produced from the original virus after two immunizations provides protection against all exiting now variants. It is truly a scientific feat that we have such a powerfully effective vaccine. People please get vaccinated – you will protect yourself, you will protect your loved ones, you will protect your fellow citizens. Do it for yourself, do it for your family.