a first dose/the first dose

[kansi]

In Kiribati, the president's office said there was "now an assumption that covid-19″ was spreading in the community. "The only way that we could fight this virus is through complete vaccination," it said. "It is critical that all work together to do our part in combating this pandemic."

About 90% of the population has received a first dose of a coronavirus vaccine, and 53% has had two shots, according to Radio Kiribati, citing official data. The national radio station said the Fiji flight was chartered by the Church of Jesus Christ of Latter-day Saints.
The Kiribati island nation was one of the world's last covid-free places. Now it's under lockdown.

How is it "a" first dose of a coronavirus vaccine?I thought it sounds like there are many first doses of a vaccine,which isn't wrodng because those who got the first dose got only one shot of a coronavirus vaccine.


Here the article says "the" first dose.
Carlton’s Liam Jones retired after opting not to get vaccinated and North Melbourne’s Jed Anderson isn’t training at Arden Street.

Players in New South Wales faced a November 19 deadline for the first dose and had to be double-vaxed by December 17.
ANTI-VAX EAGLE: Premier critical of Darling’s jab decision

 

[PaulQ]

A first dose = an example of a first dose.

Every country in the world has given its citizens a (an example of a) first dose: Kiribati's first doses are one set from many.

 

[kansi]

A first dose = an example of a first dose.

Every country in the world has given its citizens a (an example of a) first dose: Kiribati's first doses are one set from many.

I see...I think I understand.

then why is it the first dose here?
ANTI-VAX EAGLE: Premier critical of Darling’s jab decision
Players in New South Wales faced a November 19 deadline for the first dose and had to be double-vaxed by December 17

 

[dojibear]

It is the first dose out of two doses.

 

[puli_dog]

I'll try to explain the difference using apples.
(Don't know why, but I'm more at ease with apples )
So:
Have a first apple:
Have an apple as your first apple. This is your first apple, one of these available apples will be your first, and possibly you'll come back for a second and a third.

Have the first apple:
Have the apple that you're expected to take, today, this specific apple. Don't know if you'll come back for more, we are focusing just on the fact that you are taking an apple, your very first apple, and that's all for now.

Does it sound convincing? If not, I can use oranges if you like

 

[kansi]

It is the first dose out of two doses.

I see..when you ask someone about covid 19 vaccination, would you ask :
Are you done with a first dose?
Are you done with the first dose?

 

[kansi]

Have the apple that you're expected to take, today, this specific apple.

I can't really understand this yet..in the situtation we are expected to have an apple, we should say "Have the first apple."?

 

[puli_dog]

I can't really understand this yet..in the situtation we are expected to have an apple, we should say "Have the first apple."?

Not simply an apple, but the first apple....
Anyway my post was not meant to set any rule whatsoever, but just to convey my feeling on a vs. the usage

 

[Ikwik64]

"A first dose" and "the first dose" are often interchangeable.
"A first dose" would be preferred when you are thinking of one "first dose" among many (each member of the population receives a "first dose").
"The first dose" would be preferred when you are thinking of the first "dose" in a sequence (such as the sequence of doses received by one person).
So in the first example,

About 90% of the population has received a first dose of a coronavirus vaccine...

"a first dose" refers to the first dose received by each person, among all the first doses received by everybody.
In the second example,

Players in New South Wales faced a November 19 deadline for the first dose...

"the first dose" refers to the first dose in each individual sequence.
But in my opinion, you could swap them around in these examples with no real change in meaning.

 

[kansi]

"A first dose" and "the first dose" are often interchangeable.
"A first dose" would be preferred when you are thinking of one "first dose" among many (each member of the population receives a "first dose").
"The first dose" would be preferred when you are thinking of the first "dose" in a sequence (such as the sequence of doses received by one person).
So in the first example,

"a first dose" refers to the first dose received by each person, among all the first doses received by everybody.
In the second example,

"the first dose" refers to the first dose in each individual sequence.
But in my opinion, you could swap them around in these examples with no real change in meaning.

I see.. I always associate "a" first dose with a sequence of the first dose and the second dose. But it's not always that we think of the sequence when talking about "a" first dose. When we talk about a first dose among many first doses, we say "a" first dose. When we talk about the sequence, we say "the" first dose.

Do I understand you?

 

[Ikwik64]

I think so, but like I said, it doesn't always make much difference in practice.

 

[kansi]

I think so, but like I said, it doesn't always make much difference in practice.

I see...is this like the auther just happens to be a person who thinks of a first dose among many first doses in the first example and the auther happens to be a person who thinks of the first dose of a required set of two doses in the second example?if a different auther wrote the first example sentence , it's natural that s/he would use "the" first dose in the first example and "a" first dose in the second example?

 

[Ikwik64]

Yes that's how it seems to me.
(It's spelt "author" by the way )