Coronavirus: Which countries have begun administering vaccines and which are leading the pack

As the number of COVID-19 cases nears the 100 million mark, an unprecedented vaccination blitz is underway in many countries across the globe.

Our World In Data (OWID), which pulls figures from official government sources, is currently tracking more than 50 countries which are actively vaccinating segments of their populations. 

They range from the tiny island nation of Bahrain to the United States. New Zealand, however, isn't among them and won't likely start receiving batches until March. 

Not every country with a campaign underway is rolling out the same vaccine and some are currently only targeting essential workers. However, all have a laser-like focus on protecting their citizens from the SARS-CoV-2 virus.

OWID groups countries into categories depending on the availability of vaccines to their populations. Just Bahrain has universal availability, while Saudi Arabia, Italy, the United Kingdom and Costa Rica are vaccinating key workers, clinically vulnerable groups and the elderly. Other countries are either vaccinating one or two of these groups, or have not begun their vaccination campaign at all.

In terms of share of the population which has received at least one dose of a COVID-19 vaccine, Israel is ahead of the pack. OWID reports that as of January 18, 24.91 percent of the country's population has received at least one vaccine dose. 

Having a single dose doesn't automatically mean someone is fully vaccinated, however. Israel, like many countries, is using the Pfizer/BioNTech vaccine which requires two doses. Others, like the Johnson & Johnson vaccine, require patients to have just a single jab.

With more than 2.1 million people having received a single dose, there are several explanations for Israel's so far successful vaccination campaign, such as the small size of the country making the logistics of distributing the vaccine more straight-forward and its digitised health sector network. 

Behind Israel, the United Arab Emirates has the highest share of people who have had at least one dose, followed by Bahrain, Gibraltar and Northern Ireland. 

But in terms of the raw number of people who have at least one jab, the United Kingdom is way out in front with 4.06 million people. 

There's been a concerted effort by the Brits to vaccinate all vulnerable groups as quickly as possible in light of the highly transmissible variant found there late last year. When announcing a nationwide lockdown earlier in January, Prime Minister Boris Johnson said restrictions would likely only be removed in February if the vaccine rollout went to plan.

OWID is also tracking the share of the population which have "received all doses prescribed by the vaccination protocol". It doesn't include countries which don't report the breakdown of first and second doses. 

Again, Israel is in front with 4.52 percent of its population having received all necessary doses. It's followed by the UAE, the UK, and the US.

Of particular concern during the vaccine blitz is that less wealthy countries may be among the last to get access. World Health Organization Director-General Tedros Adhanom Ghebreyesus warned the world is on the brink of "catastrophic moral failure" in sharing COVID-19 vaccines and urged countries and manufacturers to spread doses more fairly around the world.

Opposition MPs in New Zealand have criticised the Government for not yet having vaccines in the country. Aotearoa has invested in vaccines from Pfizer/BioNTech, Janssen, the University of Oxford/AstraZeneca, and Novavax. 

ACT leader David Seymour this week questioned whether Aotearoa's timeline for delivery is based on supply constraints or because we've signed contracts that give the drug companies discretion to decide which countries need vaccines most. 

A New Zealand Ministry of Health spokesperson says there are a number of factors that may impact when Aotearoa receives its first doses. 

"It is a range and combination of variables that we and companies have to weigh up that reflect the global situation, the speed at which companies can produce and deliver vaccines, the risk profile of each country, the regulation process in each country and the rate and severity of infection."

Many countries struggling with the pandemic got their vaccination campaigns underway in December via 'emergency-use authorisation'. However, New Zealand - which doesn't have any community cases of COVID-19 - doesn't have such a method and will instead likely use a "provisional approval route", which sets a time limit and allows health authorities to place conditions on the approval.

Medsafe is waiting on data from vaccine developers for regulators to make an assessment and clear the vaccines for use.