Pneumococcal Conjugate Vaccine (PCV13)

What is this disease?

Pneumococcal disease is an infection by Streptococcus pneumoniae bacteria, aka “pneumococcus”. Although the name of this bacteria suggests that is the cause of pneumonia, pneumonia can be caused by many different things. S. pneumoniae is the most common cause of bacterial pneumonia. The most common cause of pneumonia in children under 5 years is viral; viral pneumonia cannot be treated with antibiotics and this vaccine does not prevent it. Viral pneumonia is typically mild. Many people (up to 90%) are carriers of S. pneumoniae and are not infected by the bacteria. Most infections of this bacteria are mild that may prompt the child to see a doctor if a fever is involved. This bacteria has been known to cause ear infections (about half of cases), sinus infections, pneumonia, meningitis, and blood infections.

This bacteria is spread through respiratory fluids, although it is uncommon for someone to contract an infection from an infected individual. This disease seems to be more prevalent in the winter and early spring. Children that are more susceptible to S. pneumoniae infection include those that are: missing spleen function, immunocompromised, in childcare and under the age of 2, have cochlear implants, and from these groups-Alaska Native, African American, American Indian (Navajo and White Mountain Apache).

Statistics

In the US, 90% of serious cases, and >95% of the deadly S. pneumoniae infection are in adults.

Annual Burden of Pneumococcal Disease in in US Children*

Syndrome	Cases
Bacteremia	13,000
Meningitis	700
Death	200 cases
Otitis media	5,000,000 cases

*Prior to routine use of pneumococcal conjugate vaccine

The first vaccine for S. pneumoniae in US was cleared in 1977. The first conjugate vaccine in the US was in 2000, PCV7. The current vaccine PCV13 was cleared by the FDA in 2010, it vaccinates against 13 types rather than 7 but is otherwise the very much the same vaccine. The blue bars in the graph below are for invasive infections from all strains of the bacteria, the gray bars are those covered by the PCV13 vaccine.

In 2000, there were 14.5 million pneumococcal cases worldwide, in children under 5 years. 735,000 of those were fatal. The following maps depict the distribution of these cases.

How do you treat this disease?

Most mild cases will resolve without treatment. If infection with S. pneumoniae is suspected as sample will be taken to confirm infection. Treatment will be initiated with antibiotics once the infection is diagnosed from the sample, usually these will be taken by mouth and care is in the home. Antibiotic resistance is present in 3/10 of S. pneumoniae strains and specific antibiotics will be able to be chosen to fight these tougher infections from a sample. Antibiotic resistance is a serious problem we are facing today. Always finish a course of antibiotics prescribed to you. Do not pressure a physician to prescribe antibiotics as they are not appropriate for all infections, including viral infections.

Preventative measures include breastfeeding for up to two years of age, keeping your child out of big daycare centers, good hygiene & health habits, and avoiding smoking in the home.

How effective is this vaccine?

A large clinical trial comparing vaccinated and unvaccinated children showed that PCV7 reduced invasive infection by 97%, pneumonia by 20%, and ear infections by 7%. See the above bar graph.

Side-effects of vaccine

Children that have reacted to prior doses of this vaccine or the DTaP vaccine should not receive this vaccine. (Diphtheria toxoid is part of this vaccine.) If your child is ill, you should reschedule any vaccination appointment.

Adverse reactions to the conjugate vaccine: apnea (more common in premature infants), hypersensitivity reaction including facial edema, dyspnea, bronchospasm, anaphylactic/anaphylactoid reaction including shock, angioneurotic edema, erythema multiforme, injection-site dermatitis, injection-site pruritus, injection-site urticaria, and lymphadenopathy localized to the region of the injection site. These severe reactions occur at a rate of 8%.

In general, reactions tend to be more intense with subsequent boosters of the injection. Local reactions occur in up to half of children (e.g. swelling, redness, tenderness). Fever and body aches occur in a quarter to a third of children. Decreased appetite and/or irritability occur in 80% of children. Febrile seizures occur in up to 14% of children with this vaccine alone; however, in combination with the flu vaccine this increases to nearly 50%. (I am in general making no recommendations for/against vaccination in these blog posts as they are only intended for educational, informed consent purposes. However, given this data, if you choose to vaccinate your child against S. pneumoniae AND influenza my recommendation is to not have these vaccines administered to your child on the same visit).

Vaccine injuries listed by the National Vaccine Injury Compensation Program include: shoulder injury and fainting. To date (current July 2017), 7 cases have been compensated in vaccine injury court.

Vaccine Schedule

Standard US schedule is: 2 months, 4 months, 6 months, and 12-15 months.

Canadian schedules are by province/territory, most are 2, 4, and 12 months; some have the last dose at 18 months, and two have a 4 dose schedule much like the US.

Alternative schedules place this vaccine in a separate month as other aluminum containing vaccines and therefore recommend it be given at 3, 5, 7, and 12-15 months.

As with any decision to give your child a drug, you should read the insert to this vaccine before having it administered. There is only one version of this vaccine, Prevnar 13, made by Wyeth/Pfizer. You can find it before your appointment with a simple internet search. Do not give your child Tylenol before this vaccine as it can decrease the antibody response, which is the primary measure of effectiveness to vaccines.

References:

CDC Website

Mayo Clinic Website

National Vaccine Injury Compensation Data accessed 7/17/17.

Pediatrician websites (alternative schedule data only)

Prevnar 13 Insert, FDA website

Public Health Agency of Canada

WHO Website