Recently, Uganda launched the new 10-valent pneumococcal vaccine (PCV
10) that is expected to protect 1.5m children below one year against pneumonia
infections by end of the year. I interviewed Seth Berkley,
the Global Alliance for Vaccine Initiative (GAVI) CEO about the new vaccine.
GAVI is channelling over 5m doses of the new vaccine to Uganda.
Below
are the excerpts of the interview.
What are
pneumococcal diseases and what is their impact?
Pneumococcal
disease (PD) is caused by the bacterium Streptococcus pneumoniae, also
known as pneumococcus, and is the number one vaccine preventable cause of death
in children under 5 years of age globally. Pneumococcus is the most common
cause of fatal pneumonia in children. In Uganda, it is estimated that pneumonia
is responsible of 17% of the deaths in children under 5.
What are
the symptoms of pneumococcal disease?
Pneumococcus is the most common cause of fatal pneumonia in children. Other
life-threatening pneumococcal infections include meningitis and sepsis.
What
complications arise from pneumococcal disease?
The pneumococcus is the most common cause of
invasive (serious) bacterial infections in children, including meningitis,
bacteremia (infection of the blood), and pneumonia (infection of the lungs).
The pneumococcus is also the most common bacterial cause of acute middle ear
infections in children
How is
pneumococcal disease transmitted?
The bacterium spreads from person-to-person via respiratory droplets -
if the infected person coughs or sneezes in close proximity to other people,
the other people may become infected.
Why is
pneumococcal disease a health problem in Uganda and the world?
It is one of the major causes of under-5 children’s
deaths. Of children under five with suspected pneumonia in Uganda, only 73% are
taken to an appropriate health care provider, and 47% receive antibiotics.
About 60% of infants less than 6 months are exclusively breastfed.
Who is at
risk of acquiring pneumococcal disease?
While persons of any age can
acquire pneumococcal disease, young children, particularly infants, are most
vulnerable. Immunity-weakening conditions such as malnutrition, HIV/ AIDS, low
birth weight, and non-exclusive breastfeeding put children at greater risk for
pneumococcal disease.
How can
pneumococcal disease be prevented?
The Global Action Plan for Prevention and Control of
Pneumonia (GAPP), issued by WHO and UNICEF, recommends a three-pronged approach
to address child pneumonia that includes protection (exclusive breastfeeding
and improved nutrition), prevention efforts (including routine use of measles, Hepatitis
B and pneumococcal vaccines), and treatment (appropriate antibiotics). GAPP
estimates that scaling up coverage of these key interventions to 90% could help
prevent more than two-thirds of childhood pneumonia deaths worldwide.
What
pneumococcal vaccines has GAVI made available to Uganda and other countries?
Pneumococcus comes in 90 varieties
or “serotypes.” Three existing pneumococcal conjugate vaccines (PCVs) protect
against 7, 10, and 13 of the most common serotypes. The 10- and 13-valent
pneumococcal vaccines cover more than 70% of the invasive pneumococcal disease
(IPD) causing serotypes afflicting African children. Uganda introduced the
10-valent pneumococcal vaccine (PCV 10).
Which new
vaccines are currently in development and why are new vaccines needed?
New vaccines are needed to protect against additional serotypes of
pneumococcus to better protect children. Also, efforts are been made to find
less expensive vaccines.
Are there
people who should not be vaccinated? If yes, why?
PCV are considered safe in all target groups for
vaccination, including immuno-compromised individuals.
How and
when should the PCV be administered?
The PCV-10 should be given in
three doses. The minimum age at first dose is 6 weeks, with a minimum interval
of four weeks between the subsequent doses - e.g., 6, 10 and 14 weeks. Ideally,
PCV-10 should be given simultaneously with other childhood vaccinations: DTP
(for Diphtheria), Hib (Hepatitis B) and Oral Polio Vaccine administration.
Should HIV
positive individuals receive the PCV?
Yes, pneumococcal vaccination is
recommended in HIV infection to help reduce invasive pneumococcal disease.
Studies have shown that children with HIV/AIDS are 9-40 times more likely to
contract pneumococcal disease than HIV-negative children, and may also be more
likely to contract antibiotic-resistant strains of the disease. In fact,
pneumonia is the most common infection leading to hospitalization among
HIV-infected children. In Uganda, there are an estimated 1.4 million people
currently living with HIV/AIDS, about 190,000 of whom are children under age of
15.
Do adults need the PCV? How often, if at all?
The GAVI supports
immunization in children, because most complications arise in young children.
PCVs for immunization of older populations and the potential use of such
vaccines for immunization in pregnancy to protect new born babies are currently
not considered sufficient by the World Health Organization (WHO) to make policy
recommendations.
Does the
PCV have any side effects, mild or otherwise?
Which ones?
The safety of pneumococcal
conjugate vaccines for children has been well demonstrated in clinical trials
and confirmed after the distribution of more than 198 million doses worldwide.
Post-licensure surveillance has found that the use of childhood pneumococcal
vaccine also protects unvaccinated children and adults by reducing
transmission.
What
impact has the PCV had in countries where it has been introduced?
Immunization with PCV7 in the United States, the first country that
introduced broadly the vaccination, has led to profound reductions in the
disease burden among adults in the first 7 years of the program. The impact of
PCV in GAVI eligible countries is being carefully monitored as part of routine
sentinel surveillance.