A year ago I wrote an article titled Ten Good News About Coronavirus . The goal was to show that science, knowledge and cooperation are essential to fight the pandemic. We do not know what will happen in the coming months and the new genetic variants are cause for uncertainty, but a year later the message is the same: advances in science encourage us to be optimistic and to see the glass half full.
1. There are more articles on SARS-CoV-2 and covid-19 than on malaria
A year ago we were amazed that in just over a month since the first cases were reported there were already more than 164 scientific articles in PubMed about the new virus and the disease.
Today that figure has multiplied by more than 600 and already exceeds 100,000 articles, more than those that appear under the heading of “malaria”, for example. More than 4,800 ongoing studies on treatments and vaccines are registered. We know more about SARS-CoV-2 and covid-19 than about other diseases that we have been studying for decades.
2. More than 200 new vaccines
A year ago it was highlighted that there were eight new projects on vaccines against the SARS-CoV-2 coronavirus. According to the bioRENDER portal, there are now more than 195 candidates, at least 71 already in clinical trials. These employ all kinds of technologies: live attenuated viruses, inactivated viruses, protein subunits, recombinant viral vectors, virus-like particles (VLPs), DNA, and mRNA.
Never has so much money been invested and there has been so much collaboration for the development of vaccines between public and private entities, research centers, universities, pharmaceutical companies, companies and NGOs. Some projects have been abandoned, but others are already authorized by the WHO: Pfizer / BioNTech and Moderna with mRNA technology, AstraZeneca / Oxford and Sputnik V with recombinant adenovirus technology and the Chinese Sinopharma, with inactive coronaviruses.
At least 20 other vaccines are already in phase III clinical trials and in the coming weeks and months they may be approved, if the results are satisfactory.
3. mRNA vaccines are very safe
One of the possible serious effects of vaccines is anaphylaxis, a life-threatening allergic reaction that usually occurs shortly after the vaccine is given.
Data from the first month of vaccination have been analyzed in the USA, where more than 17.5 million doses have been administered (exactly 9,943,247 of the Pfizer / BioNTech vaccine and 7,581,429 of the Moderna vaccine).
The Vaccine Adverse Reaction Reporting System (VAERS) has recorded only 66 cases of anaphylaxis (47 with the Pfizer / BioNTech vaccine and 19 with the Moderna vaccine). This represents less than 4 cases per million doses or 0.0003% of all doses analyzed. Twenty-one (32%) of those 66 cases had had previous cases of anaphylaxis for other reasons. No deaths have been detected.
If compared with the number of COVID-19 cases, the sequelae left by the disease and the number of deaths, the benefit of vaccines greatly outweighs the possible adverse effects. All this allows us to affirm that, for the moment, mRNA vaccines are very safe.
4. Vaccines are effective
Israel is the country with the largest population already vaccinated. In early February and since the campaign began in December, more than 3.67 million Israelis had received the first dose of the Pfizer / BioNTech mRNA vaccine. This represented about 40% of the country’s population. More than 28% had also received the second dose. Among those over 60, more than 80% had been vaccinated.
Preliminary data shows that vaccination is being effective. The number of infections is declining significantly, especially among people over 60. In this age group, there have been 56% fewer infections and 42% fewer hospitalizations and 35% fewer deaths from covid-19 after the second dose.
The results with the two doses are excellent: of the 523,000 Israelis vaccinated with two doses, there are only 544 cases of COVID-19, only 4 cases of severe COVID-19 and zero deaths. These data confirm those obtained in previous clinical trials.
But you don’t have to go to Israel. In Asturias on February 15, the figure of 2 000 people died from covid-19 since the start of the pandemic had been surpassed. Among them, there was a large proportion of people living in nursing homes, where the impact has been considerable. However, at this time the situation is beginning to be relatively controlled thanks to vaccination efforts specifically directed at residents and workers who care for them.
The effect of the vaccine is evident when comparing mortality among elderly people living in residences (almost all vaccinated), in which it drops sharply, and the number of deaths in people living outside of them (not vaccinated), among the which increases considerably.
In addition, the results of a preliminary study in England have just been published showing that the Pfizer / BioNTech mRNA vaccine is effective in preventing infection in symptomatic and asymptomatic adults, including against the “British” variant B1.1.7.
5. Confidence in vaccines increases
After more than 160 million doses of vaccines against COVID-19 administered, the population’s confidence in vaccines is increasing. For example, a survey of 13,500 people from fifteen countries in Europe, Asia and Australia was conducted between November 2020 and January 2021. In the month of November, before countries began to approve vaccines, only about 40% of those surveyed would get the covid-19 vaccine and more than 50% were concerned about possible side effects.
By January, more than half would get the vaccine and the number of people worried about side effects had dropped slightly.
The United Kingdom was the country in which more people expressed their willingness to be vaccinated (up to 78% of those surveyed) and in Spain the proportion of people willing to be vaccinated went from 28% in November to 52% in mid-January.
6. The immune response against the virus lasts at least eight months
Serological tests that measure antibodies to SARS-CoV-2 do not reflect the full potential, duration and memory of the immune response to the virus. Knowing how long the immune response against the virus lasts is essential to determine protection against reinfections, the severity of the disease and vaccine efficacy.
It has been verified that, although there is some heterogeneity in the response according to each individual, in most of the people in whom it has been analyzed they maintain a robust humoral (antibodies) and cellular (T lymphocytes) immune response, of at least between 6 and 8 months after infection, regardless of whether they are mild or severe.
7. New treatments for the most serious cases
We already know that covid-19 is much more than pneumonia. Much more is known about the disease and, although we do not currently have a specific antiviral that inhibits the virus, there are combinations of treatments that greatly improve the prognosis and reduce mortality in the most severe cases. Antivirals, anti-inflammatories, anticoagulants, corticosteroids, cytokine storm inhibitors, and monoclonal antibodies are some examples.
There are more than 400 ongoing clinical trials testing different treatments and combinations. For example, according to the international clinical trial Recovery, the combination of tocilizumab (a monoclonal antibody directed against the interleukin-6 receptor, approved for the treatment of rheumatoid arthritis) and dexamethasone (a potent synthetic glucocorticoid that acts as an anti-inflammatory and immunosuppressant), can reduce deaths by almost half in the most severe patients with COVID-19.
On the other hand, preventive treatment with anticoagulants in hospitalized covid-19 patients is associated with 30% less mortality at 30 days, and no adverse effects of bleeding.
8. No flu
There was serious concern about how the SARS-CoV-2 overlap with other frequent respiratory pathogens was going to behave in the winter months. A “perfect storm” situation could not be ruled out in which SARS-CoV-2 coincided with other viruses, such as influenza or respiratory syncytial virus, which cause bronchiolitis and pneumonia and are responsible for frequent hospitalizations and deaths in certain sectors of the most vulnerable population.
It had been suggested that the risk of death in people infected by influenza and SARS-CoV-2 simultaneously was higher than in those who were only infected by the coronavirus, especially in those over 70 years of age. The coincidence of several respiratory viruses with SARS-CoV-2 could have caused a carnage in the elderly.
The good news is that this season the flu and other respiratory viruses have disappeared, both in the months of June to August in the southern hemisphere and now in the northern hemisphere.
We cannot rule out that this could be a problem next year (the seasons in which the flu causes higher mortality are usually preceded by more benign seasons), but this year has been a real relief to health systems.
Several are the causes that can explain this decline of the flu. It should first be remembered that SARS-CoV-2 and the influenza virus are very different viruses.
It is very likely that the shorter incubation period of the flu, the existence of previous immunity, the intense vaccination campaign this year, the confinement measures, reduction of trips, use of a mask, hygiene and social distancing have had a greater effect. in reducing the transmission of this virus. On the contrary, the transmission of the coronavirus is also much more influenced by the effect of aerosols, the role of super-spreaders and asymptomatic patients.
9. We can follow the evolution of the virus in real time
The effect that the new SARS-CoV-2 genetic variants may have on vaccination and the course of the pandemic is uncertain. Because genetic changes can have a potential effect on how the virus behaves, its analysis and monitoring is essential. The good news is that today we have the ability to follow the real-time evolution of the virus and the emergence of new genetic variants.
There are already more than 260,000 SARS-CoV-2 genome sequences available in databases. Those sequences come from as many isolates obtained from human samples from February of last year to the present time. Although nucleotide changes are the primary source of genetic variation for SARS-CoV-2, insertions, deletions, and even recombinations have also been detected.
All of this makes it possible to make phylogenies (“kinship” relationships between viral variants) that can be used to make temporal estimates (when new variants emerge), characterize how the virus spreads geographically, reconstruct the epidemiological dynamics within a region, and analyze how it is spread. adapt over time. The analysis of the SARS-CoV-2 sequences is unprecedented, in the GISAID database (Global Initiative on Sharing Avian Influenza Data) there are more than 580,000 shared sequence data. It is the first time that the evolution of a pandemic virus has been followed in real time.
10. The global pandemic decreases
We do not know how the pandemic will develop in the coming months. Given the intensity that it has had so far, it is likely that there will be new waves, but perhaps less intense. We do not know what a possible fourth wave will look like, nor the effect that the new genetic variants that appear may have, but the good news is that at the global level the pandemic is decreasing at this time.
Perhaps it is a combination of several factors: the virus behaves seasonally, the population acquires a certain group immunity by natural infection or by vaccines, perhaps the virus in this natural process of variation and mutation is leading to less virulent forms and it adapts to its new host.
We do not know for sure, but for now there is still reason for hope.
Ignacio López-Goñi, Professor of Microbiology, University of Navarra
This article was originally published on The Conversation. Read the original.
