Johnson and Johnson covid vaccine efficiency, side effects, doses

Johnson and Johnson Covid Vaccine

Johnson and Johnson’s Janssen covid 19 vaccine is aiming to provide immunity against coronavirus infection. So this vaccine will help to build immunity against covid 19 illness.

Johnson and Johnson Vaccine is Made By

As the name suggests Johnson and Johnson’s Janssen vaccine is made by the Janssen Pharmaceuticals Companies of Johnson and Johnson.

Johnson and Johnson covid Vaccine Type

The type of Johnson and Johnson’s covid vaccine is Viral Vector.

Johnson and Johnson Vaccine Process

This vaccine is one dose vaccine. So only one shot is needed.
The vaccine is given into the muscle in the upper arm, preferably in the deltoid muscle.

Johnson and Johnson Vaccine Booster

The Johnson and Johnson vaccine may need a booster shot to fight against some coronavirus variants as per reports of bioRxiv. Because booster dose may increase the protective immunity more.

Johnson and Johnson Vaccine Ingredients

The Johnson and Johnson vaccine contains the following ingredients-

  • Recombinant, replication-incompetent Ad26 vector that encodes a stabilized variant of the S protein (Spike protein) of SARS-CoV-2.
  • Polysorbate-80
  • 2-hydroxypropyl-beta-cyclodextrin
  • Citric acid monohydrate
  • Trisodium citrate dihydrate
  • Sodium Chloride
  • Ethanol

Johnson and Johnson Vaccine Efficacy

Who can receive Johnson and Johnson Vaccine?

AS per the official website, The Johnson and Johnson’s Janssen covid 19 vaccine is recommended for those who are above 18 years of age.

Who can not receive Johnson and Johnson Vaccine?

People who formerly experienced severe allergic reactions (anaphylaxis) or an immediate allergic reaction that may not be severe, to any ingredients of this vaccine should not receive this vaccine.

An immediate allergic reaction occurs within 4 hours of exposure with the symptoms such as hives, respiratory distress (wheezing), swelling of the face, etc.

Johnson and Johnson Vaccine Side effects

Side effects are common in people in the age range of 18-59 years as compared to people who are above 60 years old.

The possible side effects of this vaccine after getting the shot include two types of side effects. One is in the injection area and the other is general side effects.

Side effects in injection area

The side effects occur in the injection area includes pain, redness, swelling in the arm at the injection site.

Side effects in general

The general side effects of this covid vaccine includes fever, headache, chills, tiredness, muscle pain, nausea, fatigue.
Usually, these side effects occur within a day or two after you receive the shot. These side effects are normal as your body is building immunity. The side effects usually go away within a few days.
Also, there are reports of fainting after getting the shot. There is also anxiety like symptoms such as rapid breathing, numbness, tingling, low blood pressure, etc.

These are uncommon and normally occur due to anxiety to get the shot. These are not unexpected, can occur after taking any jab, usually, these are not serious.

Among 8 million doses of this vaccine were administered in the US in March and April 2021 and there were reports of 653 faintings and near fainting.

All these fainting events occurred within 15 minutes after getting the jab. So fainting or near fainting occur during the waiting time after getting the shot. So it is very important to wait for 45 minutes to one hour after getting the shot.

This fainting or near fainting events occur may be due to vaccine or due to anxiety, not clear to date. Also maybe related to the anxiety for the needle to get the shot.
It is not possible to predict who will experience side effects after getting the jab.

Side effects vary from person to person. Some experience very few side effects, some experience moderate side effects, and few cases there are severe side effects.
If your side effects are severe or the side effects are of concern, then it is very important to seek immediate medical attention.

Johnson and Johnson Vaccine Safety

The side effects after getting the jab are common within 7 days. In most cases, these side effects are mild. Few people had side effects that affect their ability to do daily works or activities.
There is a rare but serious adverse event after getting Johnson and Johnson’s Janssen vaccine- this serious event is blood clots with low platelets (this is known as thrombosis with thrombocytopenia syndrome, or TTS).

This event occurs at a rate of 7 per 1 million vaccinated women in the age range of 18 to 49 years. For women above 50 years and men of all ages, this adverse effect is rarer.
For people who developed blood clots and low levels of platelets, the symptoms began approximately one to two weeks after getting the shot.

You should always seek medical help if you have any of the following symptoms after getting this vaccine. The symptoms are
Shortness of breath, Chest pain, Persistent belly pain (abdominal pain), Leg swelling, Severe or persistent headache, Blurred vision, Easy bruising, or tiny blood spots under the skin beyond the injection site.

Johnson and Johnson Vaccine Effectiveness

The Johnson and Johnson covid vaccine is 66.3 percent effective in clinical trials at preventing laboratory confirmed covid 19 illness in people who got the vaccine and no history of previous covid 19 infection. People are most protected 2 weeks after getting the shot.
As per reports of the clinical trial, the vaccine is highly effective to prevent hospitalization and death in people who got sick due to covid 19. The people who got covid 19, 4 weeks after getting the vaccine, no one had to be hospitalized.

In clinical trials, it is shown that vaccine is effective if people have underlying medical conditions such as high blood pressure, obesity, type 2 diabetes, HIV infection, etc.

Johnson and Johnson Vaccine and Delta Variant

This vaccine is effective against delta variant. The trial data shows that this vaccine generated strong, persistent activity against the rapidly spreading delta variant and other coronavirus variants.

The immune response after getting the jab lasted at least eight months, as per reports to date.

In the ENSEMBLE trial, it is shown that this single dose vaccine is 85 percent effective against severe or critical covid 19 infection and showed protection against hospitalization and death due to Covid 19 illness.

This vaccine also showed effectiveness against rapidly emerging beta and zeta variants in South Africa and Brazil.

The most interesting part is, the humoral and cellular immune response generated by this single shot vaccine lasted for at least 8 months.

Data also shows that T cell responses including CD8+ T cells that seek out and destroy infected cells persisted for more than 8 months. This is the latest time frame to date.

What should you mention to your vaccination provider before you get Johnson and Johnson Vaccine?

  • Tell your vaccination provider if you have any underlying medical conditions such as
  • If you have allergies
  • If you have a fever
  • If you have any bleeding disorders or if you are on any blood thinner medicines
  • If you are having weak immunity ( Immunocompromised) or if you are on any medicine that affects your immune system
  • If you are pregnant or you are planning to become pregnant
  • If you are breastfeeding
  • If you have already received any other covid 19 vaccine
  • If you have received this vaccine previously (this is a single dose vaccine, do not take this vaccine again).


The Johnson and Johnson covid vaccine is a one dose vaccine but recent reports claimed for a booster dose. Clinical trial reports are showing this vaccine with booster dose is effective against various variants of coronavirus. Similar to other vaccines like Covaxin, Covishield, Sputnik V, Moderna etc.

This vaccine has also some side effects. But American Population has largely taken this shot and till date no such huge fatality reports are there. So apparently this vaccine is safe to use. Before taking your final decision we encourage you to check all the other vaccine details, then choose one that suits you best. Stay healthy and happy.


  1. Centers for Disease Control and Prevention
  2. World Health Organization (WHO)
  3. US Food and Drug Administration
  4. Johnson and Johnson Official Website
Found this information useful? Share with people you care