Except under certain circumstances, premature infants receive their vaccinations based on their date of birth.  For example, DPT vaccination is to be completed 2 months after the date of birth, and a baby born 9 months after the conception does not receive the vaccination 3 moths after birth. Small weight is not a cause for postponement or cancellation of vaccination. Unless there are reasons to be otherwise, vaccinations are completed based on the date of birth. However, there are two exceptional clauses

Any vaccinations to a pregnant woman must consider the possible damages to the fetus.   Even if the vaccine may not damage the fetus, consideration of vaccination must be done when the risk of effects of infection outweighs the possible side effects of vaccination.   Vaccinations to a pregnant woman must be completed during the middle or late phase of pregnancy  in order to minimize the possibility of the fetus’s deformity.

Permissible vaccinations to a pregnant woman, including basic and booster vaccination, are vaccines for tetanus, diphtheria, and influenza.

Pregnant women who did not receive booster diphtheria and tetanus toxoid vaccine within the past 10 years must receive booster vaccinations.  Pregnant women who did not receive any vaccination whatsoever (or only received it partially) must receive the basic vaccinations.   There is a precedent in which the high epidemic rate of tetanus in infants in a third-world country dropped after vaccinating the pregnant women.  The women did not experience any special side effects.

Frequently, female patients are hospitalized and experience complications from influenza during mid- to late pregnancy or confinement period.  Therefore, it is recommended that all women pregnant for more than 14 weeks receive influenza vaccines during the influenza season.   Pregnant women who have a high risk of infections and complications by streptococcus pneumonie may receive the appropriate vaccination.

If infected with hepatitis type A or B during pregnancy, the mother becomes seriously infected, and the newborn baby is born with hepatitis type B infection.  If necessary, the vaccines for hepatitis may be used for pregnant women.  There are no satisfactory answers on the safety of the baby’s development after vaccination, but theoretically, there are no risks since the viruses in hepatitis type A vaccine are inactivated by formalin and hepatitis type B vaccines are subunit antigen vaccine.  Hepatitis type B vaccines, which contain no thimerosal, are the recommended vaccine for pregnant patients.

Application of any and all live vaccines during pregnancy is forbidden, but vaccines for yellow fever may be given to pregnant woman traveling in risky regions.  Pregnant women who were vaccinated against polio (completely or incompletely) may be vaccinated with IPV.

Measles, mumps or varicella vaccination during pregnancy is absolutely forbidden.   Therefore, one needs to pay attention to her immunity status for the disease above before pregnancy.  There is nothing known about the effects of varicella vaccines to fetuses.

The presence of pregnant women does not prevent the vaccination of her entire family.   Transmission of varicella from vaccinated infants to sensitive patients is rare.  However, if there is an eruption after the vaccination, transmission of the disease is possible.

When traveling to other countries, booster vaccinations are needed, depending on the destination, purpose of travel, length of stay, and other factors.

All travelers 6 months and older who are traveling to the infected area must receive live, attenuated vaccines for yellow fever.  However, the vaccine carries the risk of encephalitis, and if possible, it is recommended to postpone the vaccination until the receiver is older than 9 months. Infants younger than 4 months old have an especially high risk of encephalitis due to the vaccine, and therefore must avoid the vaccination.

Children 6 years and older who are traveling the epidemic region must orally administer the typhoid vaccine every other day for four times.  However, patients who are using mefloquine, a treatment for malaria, must administer the vaccine 24 hours before and 24 hours after taking mefloquine.

When traveling to regions with high risk of rabies, the appropriate vaccine must be injected intracutaneously or intramuscularly three times, depending on the makeup of the vaccine.   However, presence of chloroquine, mefloquine, or other treatments for malaria decreases the effects of intracutaneous injection; the vaccine must be injected to the muscle in those cases.

When residing or traveling to regions with medium to high occurrence of hepatitis type A, receive appropriate vaccinations or immunoglobin before departure.

5) Malaria

Administer anti-malaria medicines one week before arriving at the region with malaria epidemic.  (Exception: if using doxycycline, administration 1 to 2 days before the arrival is allowed).
In areas with no resistance toward chloroquine, administer chloroquine once a week.  The weeks include one week before the arrival to the region, the duration of the stay, and four weeks after the return.  When traveling to areas with resistance to chloroquine, administer mefloquine as mentioned above.