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Adult vaccination
Dewald Steyn
Department of Internal
Medicine
UFS
When to vaccinate?
1. Routine - children
2. High risk groups - adults
3. Travel – both children & adults
Smallpox in the 18th
century
• Most feared & greatest
killer
– It killed 10% of the
population
– rising to 20% in towns
and cities
• Among children
– it accounted for 1 in 3 of
all deaths
• Touched every section
of society
“Speckled Monster”
Edward Jenner
• vaccination with
cowpox prevented
the deadly smallpox
1749-1823
VARICELLA IN ADULTS
• 15 x higher mortality
• Pneumonia
– 1 to 2% of healthy adults
– Immunocompromised
adults
– 10 to 20% of affected
pregnant women
develop varicella
pneumonia
• mortality of up to 41%
Recommendations for
varicella vaccine
• All susceptible immuno-compromised individuals
– who have retained a moderate degree of immune
function
• Women in the childbearing age group who never
had chickenpox
• All susceptible healthcare workers
• Healthy adults who are exposed to children
• Dose – live attenuated vaccine
– > 1 year (single dose)
– > 13y (2 doses, 1 month apart)
Varicella Post-exposure
prophylaxis:
1. VZIG
 6ml (3 ampoules) given imi
– to all pregnant women or immuno-suppressed patients
•
who are exposed to varicella and who may lack antibodies to
the virus (only 25% are truly susceptible)
– as soon as possible after exposure
•
even up to 96 hours after exposure
– the primary indication for VZIG in pregnant women is
to prevent complications of varicella in the mother,
rather than to protect the foetus
Varicella Post-exposure
prophylaxis:
2. Post-exposure administration of ACYCLOVIR
– Effective in aborting VZV infections provided that the
timing is correct
– must be given relatively late in the incubation period 7 to 9 days after exposure
3. VARICELLA VACCINE
– healthy individual within about 48 to 72 hours
after an exposure
– you can prevent varicella
•
•
Given within 36 hours: 90% chance of preventing
varicella
Given within 72 hours: 75% chance of preventing
varicella
Prevention of Zoster
• Risk to develop
zoster
– vaccinees < natural
infection
• if you prevent
varicella, you
prevent rash on the
skin, you prevent
entry of virus into
the nervous system
cell-mediated immune response
Rabies + Tetanus
• 100% FATAL
but also
• 100%
PREVENTABLE
– Human rabies
immune globulin
(HRIG)
– Human diploid cell
vaccine
• Tetanus toxoid /TIG
Meningoccal Prophylaxis
• Antibiotics
– Household contacts
– Kissing contacts
• preceding 10 days
– Rifampicin – 600mg b.d x 2 days
– Ciprofloxacin – 500mg stat
– Ceftriaxone – 250mg stat
• Vaccine (2 weeks before protective Ab)
– Groups A, C, Y, W135
• Military camps
• Travelers (Africa menigococ belt or Mecca)
• Splenectomised pts, complement deficiency
Pneumococcal vaccine
• 23-valent: Prevention of bacteremic disease
– ability to prevent meningitis or pneumonia is
unproved
• its overall efficacy against pneumococcal meningitis
is assumed to be about 50%
• 7-valent conjugate vaccine
– 97.4% efficacy in preventing invasive pneumococcal
disease including meningitis from the 7 serotypes of
pneumococci in the vaccine
– and 93.9% efficacy in preventing invasive disease from
all pneumococcal serotypes
Age-specific Mortality Due to
Hepatitis A
Age group
(years)
<5
5-14
15-29
30-49
>49
Total
Case-Fatality
(per 1000)
3.0
1.6
1.6
3.8
17.5
4.1
Source: Viral Hepatitis Surveillance Program, 1983-1989
Geographic Distribution of HAV
Infection
Anti-HAV Prevalence
High
Hep A in unprotected travelers
Intermediate
Low
• 10 - 100 times > typhoid
Very Low
• 1000 times > cholera
Who should be vaccinated
against HepA?
• nursing staff and healthcare workers in contact with patients
in children's wards, infectious diseases wards, emergency
rooms and intensive care units
• day-care centre staff particularly where children have not been
toilet trained
• staff and residents of homes or institutions
• sewerage workers
• food handlers
• homosexual men
• people in contact with an infected person
• chronic liver disease or liver transplants, or people who
receive certain blood products
• travellers to areas with a high incidence of hepatitis A
Hepatitis A vaccination?
• On average, adults
with hepatitis A
miss 30 days of
work or routine
daily activity.
• Although rare
complications do
occur!
Hepatitis B is 100 times
more infectious than
HIV
Virus can survive for up to 7
days on contaminated objects
outside the body
Geographic Distribution of Chronic HBV
Infection
HBsAg Prevalence
8% - High
2-7% - Intermediate
<2% - Low
Who should be vaccinated
against Hepatitis B
•
•
•
•
•
•
Spouses and family members of infected persons
Sexual promiscuous persons
HIV positive patients, IV drug users
Health care workers
Hemophiliacs and. Pts on haemodialysis
Residents and staff at institutions for mentally retarded
patients, prisoners
• All neonates and non-immune children at 11–12y
• Contact sportsmen
• International travelers > 6 months to high endemic area
Protective Antibody level?
• Anti-HBs
> 10 IU/L
• Need for
booster dose?
– (7 to 10years)
Combination vaccine
• TwinrixR
– 720 EL.U inactivated hepatitis A virus
– 20 g HBs antigen
– 0, 1, 6 month schedule
• Twinrix Adult: > 16 years - 1ml
• Twinrix Junior: < 15 years – 0,5ml
and
Live attenuated intranasal
vaccine (LAIV) - FluMist
• intranasal trivalent, cold-adapted LAIV
– recently approved in the US
– persons aged 5 - 49 years
• 2 influenza A viruses and 1 influenza B
virus
Avian Flu
• H7N7 is unrelated to
• avian influenza virus currently in Asia
(H5N1)
• and the avian influenza reported in
chickens with no human cases in the
United States (H5N2)
Other possible prophylaxis
• Oseltamivir (TamifluR)
– Prophylaxis of Influenza (>13 years)
• 75 mg o.d
– Treatment of Influenza (>13 years)
• Initiate within 48 hours
• 75 mg b.d
• Zanamivir (RelenzaR)
• 10 mg inhalations b.d for 5 days
Health Advice for International
Travel
• General Considerations
–
–
–
–
–
Where to ?
When ?
Duration of stay ?
Reason for travel ?
Medical History:
• Illness, Drugs, Allergy, Pregnancy
– Immunizations
Advice on disease Prevention
•
•
•
•
•
•
Travelers’ diarrhea
Malaria
Dengue fever
Schistosomiasis
STD’s
Jet lag, Motion sickness, Sun protection,
Acute mountain sickness, Chronic illness,
Pregnancy, HIV
- Myth 1:
Not taking Malaria prophylaxis
• highly irresponsible
– parasites can multiply at phenomenal rates
– malaria can quickly get out of hand
• you will always be able to make the diagnosis
– symptoms will present with the same intensity
– time to progress to severe malaria may be longer
• repeated blood smears
• new antigen-assay tests
- Myth 2
The drugs work on the
parasite once it enters
the blood
 This does not occur
until 10-14 days after
being bitten
 Malanil® is the
only exception

“Prophylaxis need only
be taken while in a
malaria area”
- Myth 3
•
'the silent
killer‘
•
she does not
buzz around
your head at
night
“ I wasn't bitten,
so can I stop
taking my
prophylaxis”
Insect repellents
• DEET
– The American Academy of
Paediatrics recommends ≤
10% for children < 12 y
• Citronella oil
– less active than DEET
– shorter acting
•
must be reapplied every 4090 minutes
• Bathing, showering, sweating
– Re-apply more frequently after
Insecticide-treated nets (ITNs)
• < 5 years
– all-cause mortality: <
20%
– < 0.5 million deaths / year
in Sub-Sahara Africa
• Pregnant women
– protected by ITNs every
night during their first 4
pregnancies
– 25% < underweight or
premature babies
- Kenya
WHO
NOT RECOMMEDED
• Chloroquine resistance
• Low Efficacy (60%)
1. Mefloquine
• 250mg = 1 tab
– 1 week before
– weekly in the area
– weekly for 4 weeks after
leaving the area
• Restrict use to 1 year
• With food
Mefloquine
Not recommended
< 3 months
< 5 kg
1st trimester
Dose:
• 5 – 20 kg: ¼ tablet
• 21– 30 kg: ½ tablet
• 31- 45 kg: ¾:tablet
• > 45 Kg: adult dose
Mefloquine
• 1 in 10 000
Side Effects
– serious (never again)
• 1 in 100
– severe (will not tolerate)
• 1 in 20
– minor (may not tolerate)
• Well tolerated by children
• mental illness or
epilepsy
• prolongation of the
QTc interval
2. Atovaquone-proguanil
- Malanil®
• efficacy: 98%
• very well tolerated
• One dose per day
– 1 to 2 days before
– daily in area
– for 7 days after return
• Most expensive
MALANIL®
Dosage in Prevention of Malaria
 Adults:
 One MALANIL® /
MALARONE® Tablet
 adult strength = 250 mg
atovaquone/100 mg proguanil
 Pediatric Patients:
 dosage based on body weight
MALANIL®
Atovaquoneproguanil
Dosage for Prevention of Malaria
in Pediatric Patients
Weight (kg)
Total Daily Dose
Dosage Regimen
11-20
62.5 mg/25 mg
1 Pediatric Tablet daily
21-30
125 mg/50 mg
2 Pediatric Tablets daily
31-40
187.5 mg/75 mg
3 Pediatric Tablets daily
>40
250 mg/100 mg
1 Adult Strength Tablet
daily
3. Doxycycline
• not < 8 years
• not for pregnancy
• >15y or >45 kg
– 100mg /d
• >8y or 31kg
– 3mg/kg
•
•
•
•
•
Daily
highly effective
short term use
photosensitivity
birth control
Advantages and disadvantages
Mefloquine
Doxycycline
Mefliam®, Lariam®
Doximal®, Doxitab® or other
Atovaquoneproguanil
Malanil®
Avoid with neuropsychiatric
or epilepsy history
Avoid in porphyria
>5 Kg
not for <
Pregnancy: Yes
Pregnancy: NO
pregnancy ?
Gastro-esophageal irritation
Diarrhea
8 years
Not specifically
contraindicated with
neuropsychiatric disorders
>11 Kg
40 kg RSA
(2nd Trim)
Vivid dreams and nightmares
and insomnia
Advantages and disadvantages
continue
Mefloquine
Doxycycline
Mefliam®, Lariam®
Doximal®, Doxitab® or other
Atovaquoneproguanil
Malanil®
Mood alterations in
susceptible individuals
Dizziness and nausea
Once weekly dosage
Should start at least one week
before departure
Should be taken for four weeks
after return
Inexpensive
Skin photosensitivity
(3% in one study)
Candida super infection
Daily dose
+ for 4 weeks after return
Useful in areas of mefloquine
resistance
Inexpensive
Drug rash (uncommon)
Nausea and vomiting
Once daily dosage
Should start 2 days before
departure
Should be taken for 7 days
after return
Most expensive
Mefloquine
Doxycycline
Mefliam®,
Lariam®
Doximal®,
Doxitab®, other
brands
Efficacy
95%
Score = 3
95%
Score = 3
95%
Score = 3
Tolerance
Occasional disabling
SE
Score = 1
Rare disabling SE
Score = 2
Rare minor SE
Score = 3
Convenience
Weekly dosing
Score = 3 + 1
Daily dosing
Score = 2 -1
Daily dosing
Score = 2
After leaving
the area
Need to be taken for
4 weeks
Score = 0 + 1
Need to be taken for
4 weeks
Score = 0
Need to be taken for
7 days
Score = 2
ADULTS
Malanil®
R 500 for 12 tabs
Cost
Score = 2
Total
Atovaquoneproguanil
11
Score = 1 –1
Score = 3
9
10
Mefloquine
Mefliam®,
Lariam®
Atovaquoneproguanil
Doxycycline
Malanil®
Doximal®,
Doxitab®, other
brands
Efficacy
95%
Score = 3
95%
Score = 3
95%
Score = 3
Tolerance
Occasional
disabling SE
Score = 1 + 1
Rare minor SE
Score = 3
Rare disabling SE
Score = 2 - 2
Convenience
Weekly dosing
Score = 3 + 1
Daily dosing
Score = 2
Daily dosing
Score = 2
After leaving
the area
Need to be taken for
4 weeks
Score = 0 + 1
Need to be taken for
7 days
Score = 2
Need to be taken for
4 weeks
Score = 0
R 500 for 12 tabs
Cost
Score = 2 - 1
Total
Children
11
Score = 1
10
Score = 3
Not < 8y
8
• If the child
vomits within 1
hour after oral
dose, the dose
must be repeated
Stand by therapy
Traveler's Diarrhea
• This is the most common health problem to affect travelers
– 80% is bacterial, typically acquired from contaminated food or water
•
Attack rates among travelers to the Caribbean, southern Europe,
Israel, Japan, and South Africa range from 8% to 20%.
• Attack rates are as high as 60% within 2 weeks of travel to Mexico, the
Middle East, Asia, and the developing countries of Africa and Central
and South America.[1]
• affects 20% to 50% of persons who travel to tropical
and semitropical areas, including Latin America, parts
of the Caribbean, southern Asia, and Africa
• Watery diarrhea, caused primarily by enterotoxigenic
Escherichia coli, affects as many as 60% of short-term
travelers and is characterized by explosive, nonbloody stools
with nausea, vomiting, abdominal cramping, and fever
• Fortunately, most of these cases are self-limited to a
duration of less than 1 week.
Travel Medicine Resources
• www.cdc.gov/travel
• http://travel.state.gov
• http://wwwn.cdc.gov/travel/contentYellow
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