Johnson & Johnson vaccine effectiveness: How does jab compare to AstraZeneca and Moderna?

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The UK has approved the use of a fourth coronavirus vaccine today, the Johnson & Johnson jab. This vaccine differs from those already available as it is a single-dose vaccine, rather than requiring two separate shots. The vaccine was developed by Johnson & Johnson’s pharmaceutical arm, Janssen.

Announcing the Medicines and Healthcare products Regulatory Agency (MHRA) had approved the safety of the jab, Health Secretary Matt Hancock said: “This is a further boost to the UK’s hugely successful vaccination programme, which has already saved over 13,000 lives, and means that we now have four safe and effective vaccines approved to help protect people from this awful virus.

“As Janssen is a single-dose vaccine, it will play an important role in the months to come as we redouble our efforts to encourage everyone to get their jabs and potentially begin a booster programme later this year.”

The UK has placed an order for 20 million doses of the vaccine, which may be used for people in harder to reach areas as with just one dose needed, requesting a second appointment would not be needed.

So what do we know about the Johnson & Johnson vaccine?

Read More: Johnson & Johnson vaccine: When will newly approved jab be rolled out?

What is the Johnson & Johnson vaccine?

The Johnson & Johnson vaccine is an adenovirus vaccine.

Vaccines of this type are based on weakened versions of adenoviruses.

Adenoviruses are a group of viruses that typically infect membranes of the eyes, respiratory tract, urinary tract, intestines and nervous system, and include the common cold.

Like the Oxford/AstraZeneca jab, the J&J vaccine uses viral vector technology where a modified version of a different virus is used to deliver instructions to the body’s cells.

This then triggers the immune system to begin producing antibodies.

How effective is the Johnson & Johnson vaccine?

The J&J vaccine has been shown to be 67 percent effective overall at preventing moderate to severe Covid-19.

Studies have suggested the jab also offers complete protection from admission to hospital and death.

Comparatively, the Moderna vaccine – which requires two doses – was found to be 50.8 percent effective up to 14 days after the first dose.

After two weeks, effectiveness was around 92.1 percent.



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