The governor of the State of São Paulo said on 16/10/2020 that, when a vaccine is approved by the National Health Surveillance Agency (Anvisa), vaccination against Covid-19 will be mandatory in Estatus for the 45 million people and only those who have a medical certificate stating that they cannotwill receive the vaccine, beá exempt from receiving the immunizer. The governor of São Paulo initially stated that the vaccination against Covid-19 could start on December 15th in São Paulo, as long as Anvisa authorizes emergency use, but everything indicates that it will last until 2021, as so far there has been no opening of phase 3 studies in terms of events involving infected people, so that the group that took the CoronaVac vaccine candidate with the placebo group.
Anvisa reported that the agency will provide the answer in terms of releasing all vaccines in the shortest possible time. The President of the Republic states that vaccination will not be mandatory, period. We cannot accept the politicization of vaccines as was done with drug treatments for Covid-19. Vaccines save lives and are fundamental to collective well-being, with a huge impact on society as a whole. In the case of Covid-19, a public health emergency, we need to reduce the risk of the virus circulating, so I think they should be mandatory for everyone who can be vaccinated if they do not have any type of contraindication, yes.
Contradictions
Health Minister Eduardo Pazuello, in a meeting with governors on 20/10/2020, informed that the Brazilian government would purchase 46 million doses of CoronaVac, after approval in phase 3 confirming its effectiveness and after approval by Anvisa. But today, 21/10/2020, President Bolsonaro, who classified CoronaVac as the "João Doria's Chinese vaccine", stated that Brazil will not buy doses of CoronaVac, disallowing the announcement made by the Minister of Health. The President stated that the Brazilian people will not be anyone's guinea pig and that the vaccine needs to be scientifically proven by the Ministry of Health and certified by Anvisa.
Interestingly, this decision came shortly after Mike Pompeo, US Secretary of State, recommended that Brazil limit trade with China. Then it made my head spin, because this same president authorized the purchase of the Oxford vaccine candidate, still without proof of efficacy, and defended the indiscriminate use of chloroquines, without any scientific evidence, going against the recommendations of scientists and Anvisa. AYes, using the Brazilian population as guinea pigs and putting lives at risk. Governors and health secretaries are outraged by the decision. The scientific community, like me, is perplexed and in disbelief. The Brazilian population needs to have access a all safe and effective vaccines approved in phase 3. It is unacceptable to politicize the issue of vaccines and place personal political aspirations above the public health of the Brazilian population.
Largest mass vaccination campaign in history
It It will, without a doubt, be the largest mass vaccination campaign in history. In Brazil, future vaccines must be included in the National Immunization Program (PNI) to be distributed throughout Brazil. The issue regarding the logistics of production and distribution of Covid-19 vaccines has already been discussed in this space here and in this another article.
To vaccinate 80% of the Brazilian population, or around 170 million people, with two doses, we will need to acquire 340 million vaccines, which implies 340 million needles, syringes, vials, vial caps, needle packaging and syringes . And let's hope there are no shortages or increases in input prices. It is important to remember that both the The air network, such as vaccine storage spaces at airports and in airplane holds, with cold rooms for adequate storage, will also bring logistical challenges.
Millions of packages, cooling boxes and thermal packaging will be needed to store the vaccines, with great rigor, care, planning and organization. According to the WHO, around 25% of vaccines in the world, when they arrive at their destination, are degraded, due to failures in storage or transportation. Around 50% of vaccines arrive at their destinations without efficacy, due to temperature problems and delays in arriving at the vaccination sites. A well-designed and coordinated strategy will be required.
A Corona Vac Is it safe and effective?
CoronaVac, which, apparently, is proving to be very safe, will show good efficacy if the number of infected people in the group that took the placebo is much higher than the number of infected people in the group that took the potential vaccine. To have an initial idea of the effectiveness of the vaccine candidate, the initial conclusion of 61 events, or 61 infected volunteers, is expected among the thousands of volunteers in the group that took the placebo and in the group that took CoronaVac.
The trial suffered minor delays as the Butantan Institute has not yet been able to recruit all 13 planned volunteers and not all volunteers have already taken both doses. A curious issue is that personal protective equipment has reduced the number of infections, since the health professionals being tested are protected by strict safety protocols, precisely to avoid infection, which goes against what is desired in phase 3, which is have a certain number of events or infected people.
The Butantan Institute still does not have the first 61 volunteers infected since the phase 3 clinical study began. Only when this number is reached will the clinical study be temporarily opened to check which group the 61 infected volunteers belong to and have a preliminary analysis. Ideally, all or most of those infected would be in the placebo group, which would show good efficacy of the vaccine candidate. As the pandemic is in a descending phase, it may take time to obtain efficacy results in phase 3.
With the aim of speeding up the time to reach the minimum number of 61 volunteers with a confirmed Covid-19 diagnosis, the Butantan Institute will increase the number of health volunteers. The greater the number of volunteers, the greater the chance of reaching the number of 61 events with infected volunteers. As the spread of the disease has slowed, even those taking the placebo have not yet acquired the disease.
Sars-CoV-2 virus used nCoronaVac is inactivated
The company Sinovac and the Butantan Institute invested in the use of a known platform, using the inactivated Sars-CoV-2 virus. Once the virus is isolated and cultivated, it is inactivated by using heat or chemical reagents. This strategy has some advantages, as like other vaccines, such as rabies and flu, it is known that there are few short, medium and long-term adverse side effects. This has been confirmed in phase 1, 2 and 3 trials with this vaccine candidate. To isolate and cultivate the virus, it is necessary to use a maximum security laboratory and for this it requires investment.
This platform normally offers a humoral response, with the production of neutralizing antibodies, but not a cellular response, with the production of T cells, which was in fact observed with CoronaVac. This vaccine candidate requires the use of adjuvants to induce a good response to stimulate the immune system and lead to the production of neutralizing antibodies.
Another point is the need for two doses to induce a good immune response, which has been observed with practically all vaccine candidates in phase 3 for Covid-19. This fact makes mass vaccination strategies difficult, as already discussed in article here and in this another here.
Once approved in phase 3, information will certainly be released about which groups the vaccine is most effective in and who cannot take it. But after passing all phases with enormous scientific rigor and being approved in phase 3, the population can trust and should take the vaccine.
Clinical study shows thatAntiviral drugs remdesivir, hydroxychloroquine, lopinavir/ritonavir and interferon beta-1a are ineffective against Covid-19
The clinical study “Solidarity Essay"(Solidarity Therapeutics Trial) was carried out over 6 months in 405 hospitals in more than 30 countries. According to the World Health Organization (WHO), the results published on 15/10/2020 provide conclusive evidence that os antivirals remdesivir, hydroxychloroquine, lopinavir/ritonavir and interferon beta-1a are ineffective against Covid-19. O “Solidarity Essay” is a randomized trial, gold standard, and involved 11.266 adults, 2.750 in the remdesivir group, 954 in the hydroxychloroquine group, 1.411 in the lopinavir/ritonavir group, 651 in the interferon plus lopinavir group, 1.412 in the Interferon group and 4.088 in the placebo group, which did not received no medication.
The study showed disappointing results, with the drugs having no effect on decreased mortality, did not lead to decreased length of stay for patients hospitalized with Covid-19, did not help patients recover faster and still recorded 1.253 deaths. A Gilead Sciences, manufacturer of remdesivir, issued a note questioning the study results stating that os Benefits of remdesivir have been demonstrated in three other clinical trials.
The Great Barrington Declaration, a risky demonstration
A demonstration of around 6400 American and European scientists, known as "The Great Barrington Declaration", defends that the elderly and sick in the United States and the United Kingdom be protected and in social isolation, but that healthy people can lead their normal working lives, socializing in bars and restaurants and participating in sporting and cultural events, increasing the circulation of the virus with the aim of accelerating the achievement of collective, community, or herd immunity (I hate this word).
The signatories of the document argue that social isolation produces adverse effects on both people's mental and physical health, as well as public health. I agree with this last point, but if these same countries, both there and here, had, from the beginning, adopted the non-pharmacological measures recommended by the WHO and scientists, raising awareness among their population, we would not be in such a prolonged quarantine. The problem is not social isolation, which has saved millions of lives, but poor quarantines due to so much misinformation.
We have learned a lot about the pandemic, there is still a lot to learn, but we know that there can be cases of reinfection, that it is not just a question of who survives and who dies after being infected, as we know about the various side effects and serious consequences for the heart, in the lung, in the brain, especially wherem has the most serious illness. When moving freely, people will be exposed to the virus, some will get sick, infect other people nearby, others will die and some who survive will have consequences that may be irreversible.
We have seen the damage that Covid-19 causes in elderly people, people with comorbidities, diabetics, cardiac patients, immunocompromised people and we know that even os healthy young people can die. And this statement came at a time when the number of hospitalizations is growing in Europe and close to the US presidential election.
The Covid-19 pandemic has exposed social and economic inequalities, structural discrimination and the ills of our society. Another publication, signed by around 80 scientists in the medical journal The Lancet, states that the defense of collective immunity proposed in The Great Barrington Declaration é unethical and “a dangerous fallacy without scientific evidence” and that the absence of non-pharmacological control measures would lead to millions of deaths, prolonging the pandemic, wreaking havoc on the economy and paralyzing health systems.
There is no doubt that non-pharmacological measures such as physical distancing, avoiding crowds and poorly ventilated spaces, use of masks, respiratory hygiene and hand cleaning habits, reliable diagnostic tests, contact tracing of infected people and social isolation are essential to reduce mortality and avoid the collapse of health services.
We don't even know yet whether people who have been infected with Covid-19 and recovered will develop long-lasting immunity and, if reinfected, they can become sick and transmit the virus. The best alternative to achieving collective immunity is broad vaccination coverage, with a safe and effective vaccine.
New reinfection
An article published on 12/10/2020 in the magazine The Lancet Infectious Diseases showed a new case of reinfection, described by researchers from the Nevada State Public Health Laboratory and the University of Nevada, in the United States. O A 25-year-old patient, who does not belong to risk groups, tested positive for two infections with different strains of Sars-CoV-2 in the period of just 48 days. The second infection was considered more serious than the first and he needed to be hospitalized and receive oxygen support. Another four cases of reinfection were confirmed in Belgium, the Netherlands, Hong Kong and Ecuador and commented here.
Human challenge
An article published on 20/10/2020 in magazine Nature dstake that the British government signed a contract with thecommercial clinical research organization Open Orphan and its subsidiary hVIVO, to carry out a study known as a human challenge (human challenges). The goal is test around 30-50 healthy volunteers aged 18-30, without any comorbidity, so that they receive small doses of the Sars-Cov-2 virus, which causes Covid-19, until they become infected, in order to help in the vaccine development. TAll volunteers will be admitted to the Royal Free Hospital, in London, in a level 3 security area, under strict medical care.
The human challenge works like this, some volunteers receive a vaccine candidate and others receive a placebo and in a second stage, everyone will be infected with the Sars-CoV-2 virus. The study is scheduled to begin in January 2021, provided that receive final regulatory approval from ethics committees. The company nVivo, responsible for the challenge, has experience in previous studies with other respiratory viruses.
Note: This text does not necessarily reflect the opinion of Unicamp.
