Many people think vaccination is only for young children and that the doses in the first year are enough. The book Recommended vaccination schedules for all ages in Vietnam (Vietnam Association of Preventive Medicine, 3rd edition, 2026) calls the right approach "lifelong vaccination": each stage of life has different diseases to prevent, and the vaccination schedule needs to follow those stages.

Why adults still need vaccines

The book gives five reasons:

Many adults were not fully vaccinated as children, while many new vaccines have since become available.
Immunity after vaccination wanes over time.
Older adults and people with chronic diseases have weaker immune systems, so they catch diseases more easily and become more seriously ill.
Older adults often take many medicines, including antibiotics and immunosuppressants.
Adults are a source of infection for children at home.

In 2020, the World Health Assembly adopted the Immunization Agenda 2030 (IA2030), with the goal that everyone, at every age, benefits from vaccines.

Source: Recommended vaccination schedules for all ages in Vietnam (Vietnam Association of Preventive Medicine, 3rd edition, 2026), Part IV, section 1, pp. 175–177.

Children under 5

This is the stage when vaccines must be given early, completely and on time. Children's immune systems are not yet fully developed. Antibodies received from the mother fade and are gone after about six months. A first serious infection can leave lasting damage even with timely treatment. The detailed schedule by month of age is in Part II of the book and in the YHDP vaccination schedule calculator.

Source: Recommended vaccination schedules for all ages in Vietnam (Vietnam Association of Preventive Medicine, 3rd edition, 2026), Part IV, section 2.1, p. 177.

Adolescents (11–18 years)

Children meet many people at school. Immunity from childhood vaccines starts to wane. The end of adolescence is also when many people reach reproductive age. Vaccines recommended by the book:

Hepatitis B: complete the primary series if any doses are missing.
Measles–mumps–rubella (MMR) and chickenpox: complete the primary series or give a booster. Rubella and chickenpox in the first three months of pregnancy can cause miscarriage or birth defects.
Reduced-antigen tetanus–diphtheria–pertussis (Td/Tdap): booster.
HPV: Gardasil 9 as 2 doses (0 and 6 months, or 0 and 12 months) for boys and girls aged 9–14, and 3 doses for people aged 15–45. Gardasil (quadrivalent) is used for females aged 9–26.
Seasonal influenza: one dose every year, before the flu season.
Meningococcal: starting at 11–12 years. Adolescents are the group most likely to carry the bacteria. The book recommends broad protection against serogroups A, B, C, W and Y; the group B vaccine (4CMenB) is given as 2 doses 1 month apart.
Pneumococcal and dengue: according to the manufacturer's instructions; the dengue vaccine is 2 doses 3 months apart.

Source: Recommended vaccination schedules for all ages in Vietnam (Vietnam Association of Preventive Medicine, 3rd edition, 2026), Part IV, section 2.2, pp. 177–180.

Before marriage and before having children

Many vaccines are contraindicated during pregnancy, so the time before pregnancy is the right time to catch up. Live vaccines (measles, mumps, rubella, chickenpox…) should be completed at least 3 months before trying to conceive. The dengue vaccine should be completed at least 1 month before. The recommended list is similar to that for adolescents: MMR, HPV, Td/Tdap, hepatitis B, chickenpox, influenza, pneumococcal and dengue.

Source: Recommended vaccination schedules for all ages in Vietnam (Vietnam Association of Preventive Medicine, 3rd edition, 2026), Part IV, section 2.3, pp. 180–182.

During pregnancy

The book recommends:

A tetanus–diphtheria or Td/Tdap booster to protect the mother and pass antibodies to the baby.
Completing hepatitis B vaccination if any doses are missing.
One dose of influenza vaccine at any stage of pregnancy.
One dose of the RSV vaccine for pregnant women at around weeks 24–36.

Live vaccines must not be used during pregnancy, including measles, MR, MMR, live influenza, oral polio, rotavirus, BCG, chickenpox and the dengue vaccine. Vaccines that the manufacturer lists as contraindicated in pregnancy, such as Japanese encephalitis, HPV and shingles vaccines, must not be used either. For details, see the article "Pregnancy and breastfeeding: which vaccines to get and which to avoid".

Source: Recommended vaccination schedules for all ages in Vietnam (Vietnam Association of Preventive Medicine, 3rd edition, 2026), Part IV, section 2.4, pp. 182–183.

Health workers

Health workers are in regular contact with patients: they can easily be infected and can also infect patients. Recommended vaccines:

Hepatitis B.
Yearly seasonal influenza.
MMR and chickenpox.
Td/Tdap.
Meningococcal (broad protection against A, B, C, W, Y).
Pneumococcal and dengue.

Source: Recommended vaccination schedules for all ages in Vietnam (Vietnam Association of Preventive Medicine, 3rd edition, 2026), Part IV, section 2.5, pp. 183–184.

Older adults and people with chronic diseases

The chronic diseases of most concern are heart disease, lung disease (asthma, COPD) and diabetes. In addition to the vaccines for adults, the book emphasises:

Yearly seasonal influenza, as early as possible. Abroad, high-dose influenza vaccine is preferred for older adults; if it is not available, the standard-dose vaccine should still be given.
A Td/Tdap booster every 10 years.
Pneumococcal: PPSV23, PCV13, PCV15 or PCV20.
Hepatitis B, especially for people with diabetes, because they have frequent blood tests.
Meningococcal: use a vaccine approved for older adults, such as MenACWY-TT.
Dengue: older adults and people with underlying conditions are more likely to develop severe disease.
Shingles (from 50 years) and RSV (from 60 years) are listed in Table 2 of the book.

Source: Recommended vaccination schedules for all ages in Vietnam (Vietnam Association of Preventive Medicine, 3rd edition, 2026), Part IV, section 2.6, pp. 185–186; Part II, Table 2, p. 33.

People travelling or working abroad

Check your vaccination history and catch up to complete the national schedule.
Find out the vaccination requirements of the destination country through its embassy or WHO recommendations.
Under the International Health Regulations, yellow fever vaccine is recommended for travel to Africa and to Central and South America. It is given at international health quarantine centres.

Source: Recommended vaccination schedules for all ages in Vietnam (Vietnam Association of Preventive Medicine, 3rd edition, 2026), Part IV, section 2.7, pp. 187–188.

Note

The dose and schedule of each vaccine follow Parts II and III of the book. A pre-vaccination screening is needed before every dose. People with underlying conditions should also ask their specialist.