Polio Vaccine for Infants

About polio

Poliomyelitis, or polio, is an infectious disease caused by the poliovirus, which is part of the enterovirus group. The virus spreads through contact with bodily fluids, mainly stool but also respiratory secretions. It enters the digestive system, multiplies there, and is excreted in stool. In most cases (80%–90%), infection does not cause symptoms. In 10%–20% of cases, symptoms can include fever, headache, stomach pain, nausea, vomiting, or sore throat. In rare cases, polio can cause meningitis, which is inflammation of the membranes around the brain and spinal cord.

The most serious outcome, which occurs in less than 1% of cases, is paralysis. This happens when the virus spreads from the digestive system into the bloodstream and damages the nervous system. Paralysis usually affects the legs and can come with severe muscle pain. In some cases, it can affect the muscles needed for breathing, requiring mechanical support. The severity of paralysis depends on how many nerve cells are affected.

There is no cure for polio, and paralysis caused by the disease cannot be reversed. The only way to prevent polio is through vaccination. Additionally, good hygiene practices—like washing hands with soap and water for about 20 seconds after using the restroom, before handling food, and after changing a baby’s diaper—help prevent the virus from spreading.

The Vaccines

There are two types of polio vaccines:

• Inactivated polio vaccine (IPV): Given as an injection.

• Live attenuated oral polio vaccine (bOPV): Given as oral drops.

Inactivated Polio Vaccine (IPV): This vaccine helps the body produce antibodies that protect against severe illness and paralysis. It is part of the pentavalent vaccine (DTaP-Hib-IPV), which also protects against diphtheria, tetanus, pertussis, and Haemophilus influenzae type B. It is included in the routine childhood vaccination schedule.

Live Attenuated Oral Polio Vaccine (bOPV): This vaccine provides localized protection in the intestines, preventing the virus from multiplying and reducing its spread. It is only given to children who have previously received the inactivated polio vaccine.

To protect children and the community, it is important to receive both vaccines according to the routine vaccination schedule.

Vaccine Composition

• IPV: Contains inactivated polioviruses from three strains.

• bOPV: Contains live attenuated polioviruses.

Vaccine Schedule

IPV: Given at 2 months, 4 months, 6 months, and 12 months as part of the pentavalent vaccine.

An additional dose is given in 2nd grade as part of a vaccine that also protects against diphtheria, tetanus, and pertussis.

Due to recent polio and pertussis outbreaks, the first dose of the pentavalent vaccine is now given at 6 weeks of age.

bOPV: Previously given at 6 months and 18 months.

Due to the recent polio outbreak, the schedule has changed, and it is now given at 4 months and 6 months.

How and Where the Vaccine Is Given

• IPV: Given as an injection in the thigh for infants and in the upper arm for school-aged children.

• bOPV: Given as two oral drops.

Polio Vaccination in Israel

• 1957: IPV was introduced into the routine vaccination schedule, preventing severe illness.

• 1961: bOPV was added, helping to prevent transmission.

• 1988: The last recorded case of polio-related paralysis occurred, with 16 cases reported that year.

• 2005: bOPV was discontinued but reinstated in 2013 following a new outbreak.

• February 2022: A case of polio-related paralysis (strain 3) was detected. The virus originated from the live vaccine and mutated after being excreted in stool. When live vaccine-derived strains circulate in under-vaccinated populations, they can cause illness among unvaccinated individuals. Sewage samples confirmed widespread circulation of this strain. A nationwide polio vaccination campaign using both IPV and bOPV successfully halted the spread, preventing further paralysis cases.

• June 2022: Poliovirus (strain 2) was detected in sewage in Jerusalem. This strain has since been found across Israel, from the Golan Heights to Be’er Sheva.

Polio outbreaks in Israel are part of a global trend. In recent years, polio cases have been reported in Africa, the UK, Canada, and the US. Getting vaccinated today is not just about preventing a temporary outbreak—it ensures long-term protection and peace of mind.

Possible Side Effects and How to Manage Them

After IPV (Pentavalent Vaccine)
Some children may experience mild, temporary side effects that resolve within a day or two:

• Redness, swelling, or pain at the injection site: Apply a clean cloth soaked in warm water to the area (do not massage).

• Fever: A fever reducer can be given if needed.

• General discomfort: Some children may experience changes in appetite, prolonged crying, irritability, or drowsiness. If vomiting or diarrhea occur, continue breastfeeding and offer small amounts of water gradually.

• Rare side effects: Seizures may occur within three days of vaccination, typically due to fever. These seizures are not dangerous and do not cause permanent nerve damage.

After bOPV (Live Attenuated Vaccine)

• Fever: A fever reducer can be given if needed.

• Vomiting or diarrhea: Continue breastfeeding and offer small amounts of water gradually.