[Q&A] Pfizer·Moderna Shortened Second Dose Date When... "Individual Notification Starts Tomorrow"

Children and Adolescents Can Also Receive Leftover Vaccine Shots... Booster Shots Available from the 25th of Next Month

On the 27th, as the spread of COVID-19 continues, citizens who received vaccines are waiting in the adverse reaction monitoring area at the vaccination center set up in Bukahyeon Culture and Sports Center, Seodaemun-gu, Seoul. Photo by Mun Ho-nam munonam@

[Asia Economy Reporter Seo So-jeong] On the 27th, the government announced the COVID-19 vaccination plan for the fourth quarter and stated that the interval between messenger RNA (mRNA) vaccines such as Pfizer and Moderna will be shortened from the existing 6 weeks to 4-5 weeks. In addition, vaccinations for children and adolescents (ages 12-17) and pregnant women will begin in October, and booster shots for the elderly and high-risk groups will be administered starting 6 months after the primary vaccination. We have summarized the key questions regarding the upcoming vaccination plan.

Q. The interval between mRNA vaccine doses has been shortened from 6 weeks to 4-5 weeks. Why is this adjustment being made uniformly?

▲ Initially, the interval for Pfizer, Moderna, and other mRNA vaccines was extended to 6 weeks from 4 weeks due to uncertainties in vaccine supply. However, as the supply situation improves after October, the interval will be shortened to 4-5 weeks. With over 70% of the total population having received the first dose, shortening the interval between the first and second doses is necessary to complete COVID-19 vaccinations promptly.

Q. Who is subject to the shortening of the second dose interval from 6 weeks to 4-5 weeks?

▲ For those with second dose appointments scheduled between the 2nd week of October and the 1st week of November (October 11 to November 7), the interval will be shortened to 5 weeks, and for those scheduled in the 2nd week of November (November 8 to 14), it will be shortened to 4 weeks. Based on the second dose date, individuals who received their first dose in the 1st to 4th weeks of September (August 30 to September 26) will have a 5-week interval, and those vaccinated in the 5th week of September (September 27 to October 3) will have a 4-week interval. Additionally, if the first dose appointment is made after midnight on September 27, the second dose will be automatically scheduled 4 weeks after the first dose. However, those who have already changed their second dose appointment to earlier than 6 weeks through health centers, call centers, or vaccination sites due to personal reasons are excluded from this uniform adjustment.

Q. How can individuals receive notification of their second dose appointment?

▲ Starting from Tuesday, the 28th, individuals will be notified individually about their adjusted second dose appointment dates.

Q. What if it is difficult to receive the second dose on the uniformly adjusted appointment date?

▲ Those who find it difficult to receive the second dose on the adjusted schedule due to personal reasons can individually change their second dose appointment to within 5-6 weeks after the first dose starting October 1 through the online reservation website. Individual changes to the second dose appointment via the reservation website are possible up to two days before the originally scheduled date. When using leftover vaccines, the interval can be shortened to 3 weeks for Pfizer and 4 weeks for Moderna for the second dose.

On the 27th, as the spread of COVID-19 continues, citizens who received the vaccine are waiting in the adverse reaction monitoring area at the vaccination center set up at Bukahyeon Culture and Sports Center in Seodaemun-gu, Seoul. In the background, a staff member is moving Pfizer vaccines. Photo by Mun Honam munonam@

Q. What is the pre-registration period for children and adolescent vaccinations?

▲ For those aged 16-17 (born in 2004-2005), pre-registration will be open from 8 PM on October 5 (Tuesday) to 6 PM on October 29 (Friday). For those aged 12-15 (born in 2006-2009), pre-registration will be from 8 PM on October 18 (Monday) to 6 PM on November 12 (Friday). Vaccinations for 16-17 year olds will be conducted from October 18 to November 13, and for 12-15 year olds from November 1 to November 27.

Q. Can children and adolescents also receive leftover vaccines?

▲ Like other groups, leftover vaccine vaccinations are allowed but only from October 18 onward, which is the official vaccination period for children and adolescents. However, to use the same-day rapid reservation service via social networking services (SNS), a smartphone registered under the individual's name is required. Therefore, students without smartphones may find it difficult to reserve leftover vaccines via SNS. In such cases, leftover vaccines can be administered through the medical institution’s standby list. Currently, the Pfizer vaccine is the only vaccine approved by the Ministry of Food and Drug Safety for those aged 12 and older, so only Pfizer vaccines are available for leftover vaccinations.

Q. Who is eligible for the booster shot (additional vaccination)?

▲ Starting October 5, pre-registration will open for those aged 60 and older who have completed vaccination at least 6 months ago, residents and workers in infection-vulnerable facilities, and healthcare workers at hospital-level or higher medical institutions with fewer than 60 eligible individuals. This includes seniors aged 75 and older and residents and workers of elderly care facilities (nursing homes, group homes for the elderly, day care, short-term care) who began vaccination on April 1. Eligible individuals will receive reservation guidance via individual text messages starting 3 days before pre-registration, and vaccinations will begin on October 25.

Q. What vaccines and locations are used for additional vaccinations?

▲ Additional vaccinations are primarily administered using mRNA vaccines. Healthcare workers at COVID-19 treatment hospitals who received two doses of the Pfizer vaccine and seniors aged 75 and older will receive the Pfizer vaccine for their booster. Others will receive either Pfizer or Moderna mRNA vaccines. COVID-19 treatment hospitals, nursing hospitals, and hospital-level or higher medical institutions with 60 or more eligible individuals will conduct vaccinations on-site, while nursing facilities will have vaccinations through visits. Those aged 60 and older, residents and workers in infection-vulnerable facilities, and healthcare workers at hospital-level or higher medical institutions with fewer than 60 eligible individuals will receive vaccinations at designated medical institutions.