Last Tuesday, April 12, the Minister of Health, Carolina Darias, advanced that tomorrow, Wednesday April 14, the first vials of the Janssen vaccine, the only single-dose vaccine approved by the European Medicines Agency (EMA). With this vaccine it is expected to considerably accelerate the vaccination rate, since immunity against the SARS-CoV-2 it is obtained after a single injection, not as is currently the case with other vaccines.
Spain will receive up to 5.5 million vaccines developed by the pharmaceutical company Janssen, belonging to the conglomerate Johnson & Johnson, and initially they will be aimed at people between 70 and 79 years old.
How the Janssen Vaccine Works
The vaccine Janssen, like the vaccine developed by the Swedish pharmaceutical AstraZeneca and the University of Oxford, is of type vector viral, that is, it uses a type of virus, called adenovirus, genetically modified so that it cannot replicate in the human body, to serve as a carrier or vector of the genetic code of an antigen present on the surface of the virus (SARS-CoV-2 , causing the coronavirus).
The injection, therefore, introduces into the human organism a Covid-19 protein, but it cannot cause any damage, that is, it cannot replicate or produce any type of disease. When the body detects this protein component as an external threat, it makes a humoral and cellular immune response long-lasting that prevents future contact with the virus from causing serious illness.
Does it have side effects?
Like any other EMA approved drug and coronavirus vaccine, the Janssen and Johnson & Johnson vaccine can also cause certain Adverse effects, which usually appear one or two days after receiving the vaccine:
Serious adverse effects
The Janssen vaccine package insert tells us that if you experience symptoms of a severe allergic reaction, immediate medical assistance should be sought. These symptoms are:
– Dizziness or lightheadedness
– Changes in heart rate
– Difficulty breathing
– Wheezing, that is, a high-pitched or hissing sound when breathing
– Swelling of the lips, face or throat
– Hives or rash
– Nausea or vomiting
– Stomach ache
It should be noted that allergic reactions are rare, but it is always recommended to inform the doctor of the substances to which you cannot be exposed, in case the vaccine contains them.
Very common side effects
Very common side effects are those that affect more than 1 in 10 people. Among them the most common are:
– Muscle pain
– Pain at the injection site
Frequent side effects
Common side effects affect up to 1 in 10 people. These are:
– Redness at the injection site
– Swelling at the injection site
– Shaking chills
– Joint pain
Uncommon side effects
Uncommon side effects affect up to 1 in 100 people. These are:
– Muscular weakness
– Arm or leg pain
– Feeling of weakness
– General ill feeling
– Throat pain
– Back pain
– Excessive sweating
Rare side effects
Allergic reactions and hives are considered rare adverse reactions, affecting only 1 in 1,000 people.
Janssen vaccine efficacy
Clinical trials conducted by the company Johnson & Johnson and the pharmacist Janssen demonstrated an effectiveness of the doses of 66 % to prevent moderate to severe coronavirus disease after 28 days of application. However, if we talk about hospitalizations and deaths, this effectiveness rises to 85 %.