Measles- Vaccination and WHO’s measles elimination strategy

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Measles vaccines contain sorbital and hydrolysed gelatine as stabilizer, as well as small amount of neomycin as preservative but not Thiomersal.                                                          

Ref: Park’s textbook of Preventive and Social Medicine, 21st edition, page-138

The virus is not teratogenic.

Immunoglobulins are given because active vaccination is not done in pregnancy.

Ans. is ‘a’ i.e., 1 hour 

“The reconstituted vaccine should be kept on ice and used within one hour “.  —Park Measles vaccine :

• Type: Live attenuated, lyophilized (Freeze dried) vaccine
• Measles vaccine is live attenuated, lypholized (Freez dried) vaccine.
• Strains of virus used to prepare vaccine are Edmonston Zagreb strain (most common), Schwartz strain and Moraten strain.
• It is given subcutaneously in to middle one-third of antero-lateral aspect of thigh.
• It is given at the age of 9 months (age can be lowerered to 6 months in epidemics & malnutrition) and is repeated at 16-24 months of age.
• It has protective efficacy (sero-conversion) of 95%. Vaccination provide life long immunity.
• Incubation period of vaccine induced measles is 7 days.
• In post-exposure prophylaxis, measles vaccine should be given within 2-3 days of exposure. Incubation period of measles virus is 10 days. Incubation period of live attenuated measles virus of live vaccine is 7 days. Thus, if the vaccine is given within 2-3 days of exposure, the replication of vaccine virus takes preference over replication of wild virus.
• Diluent used for measles vaccine reconstitution is distilled water or sterile water.
• Reconstituted vaccine should be used within 1 hour.
• Usual temperature for cold chain storage is +2 to +8°C.

Ans. is ‘c’ i.e., 2010 

o In the year 2010, the world’s two most populous countries made promising advances in measles control :- i) China held the largest ever SIA, vaccinating more than 103 million children.

India started implementation of 2-dose vaccination startegy.

Ans. is ‘d’ i.e., Catch up 

WHO’s measles elimination strategy comprises a three part vaccination strategy, i.e. :-

i) Catch-up → One-time, nationwide vaccination campaign targeting usually all children aged 9 months to

• 14 years regardless of history of measles disease or vaccination status.

ii) Keep-up → Routine services aimed at vaccinating more than 95% of each successive birth cohort.

iii) Follow-up → Subsequent nationwide vaccination campaign conducted every 2-4 years targeting usually all children born after catch-up campaign.

• The priorties of countries persuing measles control include :-

i) Improve routine vaccination coverage level to at least 90%.

• Active coverage of more than 90% in catch-up and follow-up campaigns or active coverage of more than 90% with routine second dose of measles vaccine.

iii) Establish case – based surveillance with laboratory confirmation of suspected cases and virus isolation from all chains of transmission.

iv)Conduct supplementary vaccination campaign together with administration of vitamin ‘A’ in high risk areas.

• In India, measles is a major cause of morbidity and a significant contributor to childhood mortality. Prior to the immunization programme, cyclical increase in the incidence of measles were recorded every third year. With the increase in immunization coverage levels, the intervals between cyclic peaks has increased and the intensity of the peak minimized.
• Epidemic of measles occur if proportion of susceptible children is > 40%
• If measles is introduced in a virgin community, it infects > 90% of children. o Eradication of measles requires vaccine coverage >96%

Following information has been added in 22^aVe of Park

• At the 2010 World Health Assembly, member states endorsed the following targets to be met by 2015 as milestones towards eventual global measles eradication : – (i) Raise routine coverage with the first dose of measles vaccine to . 90% nationally and 80% in every district; (2) Reduce and maintain annual measles incidence to < 5 cases per million; and (3) Reduce measles mortality by 95% in comparison with estimated level in the year 2000.

Ans. is ‘a’ i.e., 9 months 

The WHO expanded programme on immunization recommends immunization at 9 months of age.

Now, second dose of measles is also given at 16-24 months in National Immunization Schedule.

Ans. is ‘c’ i.e., Can cause TSS

Measles vaccine :

• Type: Live attenuated, lyophilized (Freeze dried) vaccine
• Strains used:

1. Edmonston Zagreb Strain (Most Common)
2. Schwartz Strain
3. Moraten Strain

• Dose: 0.5 ml
• Route: Subcutaneous
• Site: Antero-lateral aspect of thigh (middle one-third)
• Age of administration in National Immunisation schedule (India): 9 months (can be lowered to 6-9 months in epidemics & malnutrition)
• Diluent for Reconstitution: Distilled Water or sterile water
• Use within 1 hr after reconstitution with diluent
• Measles (& MMR) vaccine can lead to Toxic Shock Syndrome
• Measles vaccine is contraindicated in pregnancy
• Cold chain Temperature for storage: +2 to +8 degree C
• Protective efficacy: > 95%
• Duration of Protection: Life long
• IP of vaccine induced measles: 7 days
• Measles immunoglobulin is also available for post exposure prophylaxis.
• The best age for measles vaccination is 9 months.
• The age can be lowered to 6 months if there is measles outbreak in the community. For infants immunized between 6 months and 9 months of age, a second dose should be administered as soon as possible after the child reaches the age of 9 months provided that at least 4 weeks have elapsed since the last dose.

Ans. is ‘b’ i.e., 6/10

Secondary attack rate (SAR)

SAR is defined as “the number of exposed persons developing the disease within the range of incubation period, following exposure to primary case”.

Ans. is ‘a’ i.e., Contraindicated in neomycin allergic patients

Measles vaccine may contain sorbitol and hydrolysed gelatin as stabilizers, as well as a small amount of neomycin

People with a history of an anaphylactic reaction to neomycin, gelatin or other components of the vaccine should not be vaccinated.

Ans. is ‘a’ i.e., Mop up: Vaccinate kids left with routine vaccination

The priorties of countries persuing measles control include :-

* Improve routine vaccination coverage level to at least 90%.

* Active coverage of more than 90% in catch-up and follow-up campaigns or active coverage of more than 90% with routine second dose of measles vaccine.

* Establish case – based surveillance with laboratory confirmation of suspected cases and virus isolation from all chains of transmission.

* Conduct supplementary vaccination campaign together with administration of vitamin ‘A’ in high risk areas.

 -In India, measles is a major cause of morbidity and a significant contributor to childhood mortality. Prior to the immunization programme, cyclical increase in the incidence of measles were recorded every third year. With the increase in immunization coverage levels, the intervals between cyclic peaks has increased and the intensity of the peak minimized.

 – Epidemic of measles occur if proportion of susceptible children is > 40%

 – If measles is introduced in a virgin community, it infects > 90% of children.

 – Eradication of measles requires vaccine coverage >96%

Ans. is ‘c’ i.e., < 1/100000

WHO defines elimination of measles as the absence of endemic measles for a period of 12 months in the presence of adequate surveillance.

One indicater of measles elimination is a sustained measles incidence < 1/100, 000 population. o In 2005, the World Health Assembly set a goal of achieving a 90% reduction in global measles mortality by 2010 as compared with level in 2000.

Ans. is ‘c’ i.e., Vaccination given at 6 months

Epidemic of measles occur if proportion of susceptible children is > 40%.

If measles is introduced in a virgin community, it infects > 90% of children.

Measles vaccine is given at the age of a months, but age can be lowered to 6 months in epidemics.

Measles shows a cyclic trend with epidemic every 2-3 years.

Ans. is ‘a’ i.e., 3 days

Incubation period of measles virus is 10 days.

Incubation period of live attenuated measles virus of live vaccine is 7 days.

Thus, if the vaccine is given within 2-3 days of exposure, the replication of vaccine virus takes preference over replication of wild virus.

“Susceptible contacts over the age of 9-12 months may be protected against measles with measles vaccine, provided that this is given within 3 days of exposure. This is because, the incubation period of measles induced by vaccine is about 7 days, compaired with 10 days for the naturally acquird measles.”     — Park

Ans. is ‘d’ i.e., Transmission at low level

• WHO defines elimination of measles as the absence of endemic measles for a period of 12 months in the presence of adequate surveillance.
• One indicater of measles elimination is a sustained measles incidence < 1/100, 000 population.
• In 2005, the World Health Assembly set a goal of achieving a 90% reduction in global measles mortality by 2010 as compared with level in 2000.