Just days after the Pfizer COVID-19 vaccine was granted full FDA approval, top U.S. health officials say "critical progress" is being made in the race to vaccinate more Americans.

The drug company says it is now seeking U.S. approval for a booster dose of its two-shot vaccine. Pfizer is beginning the application process for the third shot for those ages 16 and older. Pfizer says that application should be complete by the end of this week.

Meanwhile, Johnson & Johnson is also working on a booster for its COVID-19 vaccine.

As News 12 has reported, on Wednesday, the company says so far the extra dose has generated a big spike in antibodies for those who receive it.

Moderna, meanwhile, is now officially seeking full approval of its COVID-19 vaccine. The company is asking the FDA to expedite its review of the data.  As of now, Moderna only has emergency use authorization for those 18 and older.

Meanwhile, officials in Nassau County and across the country are making an effort to get more people vaccinated.

Today, the vaxmobile will be in Uniondale from 10 a.m. to 3 p.m. at the Academy Charter School.

Officials say studies show you are less likely to be hospitalized with COVID-19 if you get the vaccine.