Photographer: David Paul Morris / Bloomberg
Photographer: David Paul Morris / Bloomberg
When will the pandemic end? It’s the question that has stuck with just about everything since Covid-19 took over the world last year. The answer can be measured in vaccinations.
Bloomberg has built the largest database of Covid-19 shots given around the world, with more than 108 million doses worldwide. US science officials such as Anthony Fauci have suggested that 70% to 85% population coverage will be needed before things return to normal. Bloomberg’s Vaccine Tracker shows that some countries are making much faster progress than others, with 75% coverage with a two-dose vaccine as the target.
Israel, the country with the highest vaccination coverage in the world, goes to 75% coverage in just 2 months. The US will be there just in time to ring in the New Year 2022 (although North Dakota could be there six months earlier than Texas). With vaccinations occurring faster in wealthier Western countries than in the rest of the world, the world as a whole will need 7.4 years at the current rate.
Bloomberg’s calculator provides a snapshot in time, designed to put current vaccination coverage in perspective. It uses the most recent rolling average of vaccinations, which means that as the number of vaccinations increases, the time it takes to reach the 75% threshold will decrease.
Calculations will be volatile, especially in the early days of the rollout, and the numbers may be skewed by temporary disruptions.
For example, New York’s target date was moved to 17 months this week after a winter blizzard prevented some from getting vaccinated. Likewise, vaccination coverage in Canada has fallen by half in recent weeks due to reports of delayed vaccine shipping. Based on Canada’s most recent vaccination rate, it would take 9.7 years to reach 75% coverage. That could serve as a wake-up call for Canadian politicians and health officials, but it doesn’t mean they are doomed to a decade of social aloofness. Canada has contracts to buy more vaccine doses per person than any other country, and vaccination coverage is expected to increase.
The pace is likely to accelerate further as more vaccines become available. Some of the world’s largest vaccine production centers in India and Mexico are just getting started. More than 8.5 billion doses of vaccine have been contracted by countries through more than 100 agreements followed by Bloomberg. Only a third of the countries have even started vaccination campaigns.
Vaccinations protect against Covid-19 within a few weeks of getting the injections. But if only a few people in a community are vaccinated, the virus can continue to spread out of control. As more people get the vaccine, groups of people are starting to build a collective defense against the virus so that isolated sparks of infection burn out rather than spread to an outbreak. The concept is known as herd immunity.
In the scientific community there are conflicting definitions for when herd immunity is achieved. Is it when enough people are protected that it starts to have a measurable effect on the transmission speed? That could start long before 75% of people are fully vaccinated. Others define it as the point where outbreaks can no longer be sustained. For example, even if there is a cluster of measles cases in an unvaccinated community, herd immunity prevents it from rippling through a country.
How we turn the numbers
The vaccines available today require two doses for complete vaccination. Our coverage calculations are based on two doses per person in the population, but do not differentiate between first doses or second doses administered. Those outages can disrupt daily vaccination coverage and are not available in more than 20% of the countries we monitor.
A new vaccine from Johnson & Johnson has recently shown positive results with a single dose in a large clinical trial. When approved, we adjust the number of doses required in relation to the market share in each country.
The vaccines are not approved for use in children – those studies are currently underway. Our calculator, like the virus, includes children in the population who must be protected.
One metric that Bloomberg’s calculator doesn’t take into account is any level of natural immunity that could result from Covid-19 recovery. Badly affected areas may require a lower level of vaccination to avoid widespread transmission. While there is some evidence that people recovering from illness maintain some level of natural defenses, it is unclear how much protection is provided or how long it may last. The vaccine is still recommended for people who have recovered from illness.
The calculator is the latest feature of Bloomberg’s Covid-19 Tracker. The projections are updated daily and are based on the average daily vaccinations based on data collected from 67 countries and the US states and territories. Countries can be excluded if they are in the earliest stages of vaccinations or if they don’t keep up to date with their vaccination numbers often.
More than 108 million shots have been taken. Check out the latest numbers on Bloomberg’s Covid-19 Vaccine Tracker