Vaccine of Measles virus
المؤلف:
Baijayantimala Mishra
المصدر:
Textbook of Medical Virology
الجزء والصفحة:
2nd Edition , p185-187
2025-10-22
46
Live attenuated measles vaccines are available either in single or in combination with other viral vaccines. In 1963, the first licensed live attenuated measles vaccine became available. The first measles vaccine candidate was Edmonston strain isolated by Enders and Peebles in 1954 in cell culture from blood sample of David Edmonston a child with measles. The Edmonston B vaccine strain was the first candidate vaccine strain. It was prepared by serial passage in human and monkey kidney cells and chicken embryo fibroblast cell line. This strain was found to be inadequately attenuated. This led to the development of second-generation vaccine strains with further attenuation such as; Schwarz, Moraten and Edmonston-Zagreb which are currently in use. All these strains are the Edmonston lineage. The non Edmonston live attenuated vaccine strains are: Shanghai-191, Leningrad-16 and CAM-70. The nucleotide sequence among the various vaccine strains are minimal (<0.6%).
Presence of maternal measles antibody is inhibitory for development of protective antibody after vaccination. Approximately 85% of vaccinated children develop protective antibody when vaccinated at 9 months of age and >90% when given at 12 months of age.
Measles vaccine induces both cellular and humoral immune responses as it happens with natural infection.
Protective antibody appears during second week of vaccination and concentration rises to its peak during 3rd to 4th week. The duration of protection after vaccination is usually considered shorter than the duration of protection conferred after natural infection.
Current recommendation: Two doses of measles vaccination are recommended for all countries.
Countries with high level measles transmission with high-risk of mortality (Ex. India):
• MCV1: 1st dose—9 months of age.
• MCV2: 2nd dose—16–24 months.
Countries with low level measles transmission:
• MCV1: 1st dose at 12 months of age
• MCV2: 2nd dose preferably at the time of school enrollment.
Recommendation of supplementary dose of measles vaccine to infants from 6 months age in following situations (MCV0: supplementary dose):
• During measles outbreak
• During campaign in endemic countries
• Refugee population
• Children with high-risk of contracting measles cases
• Children born to HIV positive mother.
Recommendation for children who have received MCV0: These children should receive both MCV1 and 2.
Disadvantages of presently available measles vaccination:
• Vaccine gets inactivated on exposure to light and heat.
• Once reconstituted, loses its potency within few hours of storage.
• Maintenance of cold chain is essential.
Presence of passively acquired maternal antibodies and immunological immaturity reduces the vaccine efficacy.
Integrated Measles-Rubella Control: Measles Rubella (MR) vaccination: In 2012, Measles and Rubella Initiative (M&RI), WHO prepared planned document to achieve the goal of measles and rubella elimination in at least five WHO regions by end of 2020. In 2013, WHO regional committee of Southeast Asia (SEA) has decided to adopt the goal of measles elimination and rubella/CRS (congenital rubella syndrome) control in SEA regions by 2020. The core strategic objectives were articulated to achieve this goal:
a. To achieve and maintain high level of population immunity (at least 95%) with two doses of measles and rubella containing vaccines.
b. Develop and sustain a sensitive and timely case-based measles, rubella and CRS surveillance system.
c. Develop and maintain an accredited measles and rubella laboratory network that supports every country in the region.
d. Strengthen support and linkage to achieve the above three strategic objectives.
Measles-rubella (MR) campaign: India and ten other WHO Southeast Asian countries have resolved to achieve the goal to eliminate measles and to control rubella/congenital rubella syndrome by year 2020.
The inclusion of these two viral vaccines was decided by WHO as measles is still a killer disease in several countries like India and rubella causes severe irreversible congenital birth defects like deafness and blindness in near 40,000 children every year.
MR campaign has two phases: Campaign phase and implementation in routine vaccination phase (Table 1).
Table1. Measles-rubella vaccine
In the campaign phase, it targets the children of 9 months age to <15 years age irrespective of their vaccination status, i.e. even if they have received measles vaccine or MMR vaccine (measles, mumps, rubella) or history of measles or rubella disease.
In the implementation phase, MR vaccine has been implemented in the routine National Immunisation Programme.
First dose is given at 9–12 months of age and second dose at 16–24 months.
الاكثر قراءة في اللقاحات
اخر الاخبار
اخبار العتبة العباسية المقدسة
