The CanSino vaccine has been mired in controversy in recent weeks. First, due to a supposed low effectiveness in preventing the coronavirus and then, due to alleged irregularities regarding its purchase in Mexico.
There are a series of anomalies in the contract signed between the Secretary of Health of Mexico, CanSino Biologics and Latam Pharm, according to an investigation published this Tuesday by The report indicates at the time of signing the contract, Latam Pharma had not been incorporated , according to the Swiss corporate public register.
It also highlights that the vaccine purchase contract was signed under the laws of Singapore, which – according to lawyers consulted by that media – put the Mexican government at a disadvantage, since it does not establish CanSino’s responsibilities in case there is a problem in the manufacturing of vaccines.
In response, the Ministry of Foreign Relations of Mexico (SRE), made the Chinese laboratory CanSino and the Ministry of Health responsible for managing the contract for the acquisition of 35 million vaccines against COVID-19, for choosing their “affiliate company” in Mexico and decide the country in which the business relationship is governed (Singapore).
The purchase of the CanSino vaccine is not the only issue that worries about this immunization, which has already been applied to all workers in the education sector in Mexico.
Unlike other vaccines that are applied in Mexico, this biological has not yet received the approval of the World Health Organization (WHO) – although it has already provided data from its clinical trials -, the European Medicines Agency (EMA) or the US Food and Drug Administration (FDA).
Here’s what we know about the effectiveness and side effects of this viral vector vaccine developed by the Beijing Institute of Biotechnology and CanSino Biologics.
Cansino vaccine effectiveness
This is perhaps the most disputed point about this vaccine. According to the results of the interim analysis of Phase 3 of Cansino’s clinical trials – the last stage before its eventual approval – show that the vaccine has an overall effectiveness of 68.83% in preventing all symptomatic COVID-19 infections 14 days after application and 65.28% after the first 28 days after injection.
In the case of the prevention of severe disease, the efficacy is 95.47% after the first two weeks of application and 90.07% after four weeks.
In the results of Phase 2 clinical trials – where the safety and effectiveness of a vaccine are tested – there were no serious or fatal cases of COVID-19, according to the report published in August 2020 in the medical journal
The rapid approval of the vaccine in Mexico has raised suspicions. According to this biological, it received the approval of the Mexican authorities despite omissions and irregularities in the evaluation of the effectiveness of this formula, for example, that it was authorized without having the final results of the clinical trials carried out in the country and, in Instead, data from tests conducted in Pakistan were used.
“In reality, all vaccines for COVID-19 have obtained emergency authorization with pending results,” explained Thalía García Téllez, an immunologist specializing in infectious diseases and clinical trials, who is part of the Center for Clinical Research in Vaccines of the Public Hospitals of Paris, France.
“In fact, clinical trials are still being done for all vaccines, even though they have already been applied. It is the natural course of clinical research,” he said.
In the Univision article, citing the slides presented at a press conference by Undersecretary Hugo López Gatell, it is criticized that the vaccine has been approved despite the fact that “the lower confidence limit” of CanSino is 5%, “much for left from the minimum required “by the WHO, which accepts a minimum efficacy threshold of 30% and an average of 50%.
García Tellez told COVIDConCiencia that 5% is not about the “confidence limit” but the lower limit of the uncertainty interval that is presented in every publication of statistical analysis. “Taking this data as an absolute effectiveness is wrong. In fact, it is very likely that this number was a finger error and that, in reality, that limit is 58%”, indicates the note, replicated in
In addition, the important data on the effectiveness that is taken into account to give the authorization of a vaccine in the statistical mean, not the extremes. In fact, the WHO does not speak of “effectiveness thresholds”.
“There is no single vaccine efficacy threshold that can be applied to all of them. Any decision about the use of a vaccine or a drug always involves weighing the benefits against the risk (…) The 50% efficacy threshold established for vaccines against COVID-19 is due to the fact that COVID-19 was considered such a serious disease , that if a vaccine is only 50% effective, it is still worth using it, ”said epidemiologist Lee Hampton a.
In conclusion, the lack of transparency of the information on the vaccine may not be related to a presumed lack of efficacy of the vaccine. “It is not that the vaccine is not effective, but that the way in which it has been communicated is not correct and can arouse suspicion. But there is no evidence to say that the vaccine is not effective, ”explained García Tellez.
How many are the recommended doses of the CanSino vaccine?
The Secretary of Health of Mexico indicates that the vaccination scheme with the CanSino formula against COVID-19 consists of a single dose of 0.5 ml applied intramuscularly in the arm with less use.
The Mexican authorities indicate that it has not yet been determined whether any booster will be required in the future, so it is considered to be a single dose scheme.
What are the side effects of the CanSino vaccine
Most of the adverse effects reported in the first 28 days after the application of the vaccine were not serious and could be resolved in the first 48 hours after their appearance. The most common side effects are:
• Pain, redness, or stiffness in the application arm
• Itching at the application site
• Bleeding at the injection site (less often)
•Fever
•Muscle pain
•Fatigue
•Headache
•Sickness
•Diarrhea
•Articulations pain
•Cough
• Pain when ingesting food or liquids
•Threw up
•Decreased appetite
•Dizziness
• Changes in the mucous membranes
•Numbness
• Gastrointestinal disorders
• Inflation of joints
•Drowsiness
•Fainting
Who should not get vaccinated with CanSino?
The vaccine is contraindicated in people with a history of severe allergic reaction, anaphylaxis type and allergy to any component of the vaccine. It is also recommended that people who have recently had COVID-19 and have not yet recovered not get this vaccine. People who received convalescent plasma prior to vaccination must wait 90 days before being vaccinated.
As the CanSino vaccine trials did not include children and adolescents under 18 years of age and pregnant people, the Mexican Ministry of Health does not recommend vaccination in these population groups.
CanSino Biologics recommends that people with a history of asthma, illness and acute phases of chronic diseases be evaluated by their treating physician, considering the risk-benefit of their application.
Can you drink alcohol with the CanSino vaccine?
According to social media posts, drinking alcohol in the next three days after receiving the CanSino vaccine is not recommended. However, there are several specialists who, although this recommendation may have the best intentions, does not have any scientific support.
Given recent observations of the body’s response to alcohol consumption, there is no clear evidence that a vaccine is less effective from this fact. On the other hand, other analyzes have shown that, in the long term, moderate alcohol consumption could be beneficial for the immune system and even reduce inflammation, according to a note in Life and Style.
Although it is recommended to moderate the intake of alcoholic beverages, with this and with all vaccines against COVID-19.
The excessive alcohol consumption of alcohol can interfere “a little with the immune response, which is what we want to achieve with the vaccine,” Guadalupe Soto, an epidemiologist and academic at the National Autonomous University of Mexico, told Animal Político.
What does a moderate dose mean? According to the Centers for Disease Control and Prevention (CDC) of the United States, the unit of minimum alcohol consumption according to the type of drink ingested is called a drink or drink.
A drink can be:
• 355 milliliters of beer (with 5% alcohol content.
• 236 milliliters of malt liquor (with 7% alcohol content).
• 147 milliliters of wine (with 12% alcohol content).
• 44 milliliters of 80 proof distilled liquor (with 40% alcohol content)
It is considered an excess if a person ingests 4 or more “drinks” in the case of women and 5 or more alcoholic beverages in the case of men. For a person the consumption of more than 8 and 15 drinks on a weekly basis, can have counterproductive effects on the health of women and men respectively.
