How long are COVID-19 vaccines effective?

(Credit: Unsplash)

This article is brought to you thanks to the collaboration of The European Sting with the World Economic Forum.

Author: John Letzing, Digital Editor, Strategic Intelligence, World Economic Forum


  • Experts don’t know yet how long COVID-19 vaccines will be effective.
  • Studies of two of the most prominent COVID-19 vaccines suggest they remain effective for at least six months.
  • The CEO of one vaccine maker said immunity may start to fade within a year.

One of the most pressing questions about COVID-19 vaccines is how long they can provide protection.

It may be decades, or a matter of months – the data necessary to figure that out is accumulating every day. Pfizer’s CEO said this week that after a full regimen of doses immunity will probably start to fade within a year. According to the WHO, it’s simply too early to know the exact duration of COVID-19 vaccines because both the disease and the science deployed against it aren’t yet fully understood.

Some early evidence is promising. The viruses that caused MERS and SARS are closely related to the virus behind COVID-19, and acquired immunity to both of those diseases has proved relatively durable.

In terms of COVID-19-specific research, Pfizer and BioNTech said earlier this month that their vaccine remains effective for at least half a year after the second dose, and a study of Moderna’s version reflected a similar duration. Immunization efforts will have to play out further before we can know more for certain.

The window of immunity enabled by vaccines could have an impact on efforts to fully re-open the global economy, and re-establish a sense of normalcy. For now, though, much of the focus has been on getting that first dose into arms, something many countries are still waiting for.

Though criticism has mounted of the pace of vaccinations in Europe, the region is still clearly better off than much of the world. In the image below, countries turn a progressively darker green as the share of their population fully vaccinated against COVID-19 increases through 13 April. The darkened countries are where no related data were available yet.

US date format.
US date format. Image: World Economic Forum

People from wealthier countries who’ve been at the front of the line for vaccines have instantly become test subjects for assessing duration.

Booster shots could help address what will likely be a slow decline of immunity over time. In this way, COVID-19 may look a lot like the flu – which also produces variants, and can be addressed with a yearly shot formulated to deal with the latest mutations.

Historically, other diseases have been quelled at least in part thanks to surprisingly lasting periods of immunity. Memory B cells needed to protect against being re-infected with the deadly Spanish flu that spread around the world in 1918 endured for nearly 90 years, according to one study.

And research has suggested that memory B cells necessary to protect against re-infection with smallpox last about 60 years following immunization.

Relatively shorter periods of established immunity won’t diminish a COVID-19 vaccine development effort that’s widely recognized as an extraordinary achievement – and should only increase the public’s faith in the positive impact of science.

Image: World Economic Forum

For more context, here are links to further reading from the World Economic Forum’s Strategic Intelligence platform:

  • The messaging surrounding COVID-19 vaccines is as important as the science behind them, according to this analysis – and that’s certainly true when it comes to explaining why the US recently paused the Johnson & Johnson vaccine following reports of extremely rare side effects. (Kaiser Health News)
  • Even if they had abundant access to vaccines, would some Europeans take them? France, home to Louis Pasteur and a universal health care system, has somehow also become home to a surprising degree of vaccine hesitancy, according to this report. (The Atlantic)
  • Bhutan’s first vaccine dose was administered to a woman born in the Year of the Monkey amid chants of Buddhist prayers in late March, according to this report. Since then, the country has managed to vaccinate more than 93% of its adult population. (The Diplomat)
  • For many of us, it’s hard to feel the momentousness of the season through which we’re now living, according to this piece – in the 1950s Americans were unabashedly jubilant about the vanquishing of polio, but they’re strangely uncertain in their celebration of new vaccines. (New Yorker)
  • Hear directly from experts: this virtual panel of scientists recently addressed questions about vaccines including how they work, how they were developed, and the potential need for boosters. (Cornell University)
  • A tiny number of people will be hospitalized despite being vaccinated. Experts say we should investigate who’s most vulnerable to these “breakthrough infections,” but according to this piece, that’s often not happening. (ProPublica)
  • Vaccinate billions or lose the battle for democracy – the EU and G7 are in strong positions to lead a truly global effort to vaccinate the world, according to this analysis, but that will mean taking a hard look at patents. (Carnegie Endowment for International Peace)

On the Strategic Intelligence platform, you can find feeds of expert analysis related to Vaccination, Science and hundreds of additional topics. You’ll need to register to view.

the sting Milestones

Featured Stings

Can we feed everyone without unleashing disaster? Read on

These campaigners want to give a quarter of the UK back to nature

How to build a more resilient and inclusive global system

Stopping antimicrobial resistance would cost just USD 2 per person a year

The EU responds to US challenges by fining Apple with €13 billion

The true EU unemployment rate may have soared to 21.9%

‘No hope’ global development goals can be achieved without women, says UN Assembly President

4 big trends for the sharing economy in 2019

South Sudan: UN calls for end to inter-communal clashes, attacks against aid workers

Falsified medicines: new rules to enhance patients’ safety

Brexit: new European Parliament reaffirms wholehearted support for EU position

Sanity in times of COVID-19

This innovative project fuses journalism and music to highlight lawlessness at sea

2019 EU Budget: Commission proposes a budget focused on continuity and delivery – for growth, solidarity, security

How Egypt’s economy can continue to thrive during a global pandemic

Ebola in DR Congo: conflict zones could constitute ‘hiding places’ for the deadly virus – WHO chief

From raised fists at the 1968 Olympics to taking the knee: A history of racial justice protests in sport

Coronavirus: a common approach for safe and efficient mobile tracing apps across the EU

EU Trust Fund for Africa: new migration-related actions to protect vulnerable people and foster resilience of host communities in North of Africa

Delhi Declaration: Countries agree to make ‘land degradation neutrality’ by 2030, a national target for action

Parliament declares the European Union an ‘‘LGBTIQ Freedom Zone’’

Coronavirus response: How the Capital Markets Union can support Europe’s recovery

The fight for female medical leadership

India should ‘unlock’ freedom curbs in disputed Kashmir, urges UN human rights chief

10 cities are predicted to gain megacity status by 2030

Contact the Sting

Why lockdowns can halt the spread of COVID-19

Coronavirus: Commission adopts package of measures to further support the agri-food sector

11 lessons the history of business can teach us about its future

Inspired by orange peel, this ‘plastic’ packaging is totally compostable

When should you self-isolate, self-quarantine or social-distance?

AI will drive the societies of the future. Will the governed consent?

Record numbers of people in the UK have applied to study nursing

How governments and mobile operators are easing network congestion during the COVID-19 crisis

Fair transition to digital and green economy: a new social agenda for Europe

Parliament ready to fight for a different EU budget

How listening to patients could change the way we tackle cancer

Novartis and Johnson & Johnson to deprive Europeans of their right to Health

Innovation and entrepreneurship can cut waste and deliver the circular economy

EU: Huge surplus in the trade of services with the rest of the world

Brexit: No deal without marginalizing the hard Tory Eurosceptic MPs

Is there a way out of the next financial crisis? Can more printed money or austerity save us all?

In 1975 NASA envisioned future life in space would look like this

Why press freedom should be at the top of everyone’s agenda

How AI and satellite imaging can stamp out modern slavery

Technology is a force for peace and prosperity. Don’t let its challenges obscure this

Electronics can trigger a more circular, sustainable world – here’s how

Here are four steps SMEs can take for long-term success

Who will win the AI race? If countries work together, then the answer could be all of us

We can meet the SDGs using the wisdom of crowds. Here’s how

Deepening Europe’s Economic and Monetary Union: Commission takes stock of progress

The ASEAN Community sees the light: the genesis of a new powerful economic and political bloc and EU’s big opportunity

Mergers: Commission opens in-depth investigation into proposed acquisition of GrandVision by EssilorLuxottica

‘Growing alarm’ over Fall Armyworm advance, with cash crops ‘under attack’ across Asia

It’s a week dedicated to all EU budgets; seven days that can make or break the Union

Thursday’s Daily Brief: Press Freedom Day, Tuna Day, cultural dialogue, #GlobalGoals awards, updates on Syria, Somalia, Mali

Iran protests: Live ammunition reportedly used, says UN human rights office

Energy: EU priority projects should be aligned with 2050 climate objectives

Report on EU trade defence – effective protection against unfair trade

COP25: Italy and Mexico pave the way on climate education

The Recruitment of Children as Soldiers Explained

Europe united in not supporting a US attack on Syria

Approaching the challenges of COVID-19 vaccination

How Japan became the world leader in floating solar power

More Stings?

Speak your Mind Here

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s