Are COVID-19 vaccines working despite case spike in Michigan?

As the vaccine rollout continues in Michigan, COVID-19 cases are spiking.

This spike doesn't mean vaccines are not working, though.

Why are more young people getting sick?

The 75 and older age group has the highest number of fully vaccinated people and the lowest number of cases compared to all people older than 10.

In contrast, the 20-29 age group is seeing the most cases. However, only 8.3% of people in that group are fully vaccinated.

Related: COVID-19 update offers glimmers of hope despite case surge, death increase

While cases are increasing in this group, they are declining in the population that had access to vaccines before anyone else. Michigan's vaccine eligibility started with older people and those with health issues. Younger people were the last group to become eligible for vaccines.

All people 16 and older are eligible to get vaccines as of Monday.

That doesn't mean that the younger populations will suddenly see a case dip, though.

What does fully vaccinated mean?

It takes two doses of the Moderna and Pfizer vaccines for them to be effective. There is about a three-week gap between the first and second doses, and it takes roughly 14 days after the second shot to be fully vaccinated.

So, the people who received their first vaccines this week won't be considered fully vaccinated until mid-May.

Also, eligibility does not equal the ability to get the vaccine. Many places offering vaccine appointments, such as pharmacies, are seeing appointments quickly fill, making it difficult to secure one.

The state is continually working to expand vaccine administration capacity, but as noted, it takes about five weeks from when the first shot is received for the vaccine to become effective.

Why are fully vaccinated people getting COVID?

Vaccines are not 100% effective, and the COVID-19 vaccines were never touted as something that would completely prevent illness. Pfizer and Moderna vaccines are considered 95% and 94% effective respectively.

So, while it is rare that someone will become infected with COVID-19 when they are fully vaccinated, there's still a chance.

However, the vaccines are useful for reducing the severity of symptoms should a person catch the virus after being vaccinated.

Through March, 246 of the more than 1.7 million fully vaccinated people in Michigan had tested positive for the virus. This number is not more than the amount of vaccinated people health officials expected would get the virus, given the effectiveness of the vaccines.

Officials noted that some of these people could have been positive before receiving the vaccine and thus did not catch it after. Even if all 246 people caught COVID-19 after getting vaccinated, that is still a small proportion of all people fully vaccinated.

Additionally, health officials said that the vaccinated people who got sick tended to have less severe symptoms than unvaccinated people.

Of the positive cases, 129 had no data entered about hospitalizations, while 117 did have that information. Eleven were hospitalized, 103 were not, and three were marked as unknown.

According to MDHHS, three people older than 65 who were fully vaccinated have died. Two of those deaths were within three weeks of completion of vaccination.