MMR - a triple vaccine against measles, mumps (mumps) and Rubella VAS - anti measles vaccine VAR - anti rubella vaccine
The three components of the MMR - measles, mumps and anti-rubella - vaccines are produced from virus strains attenuated.
Vaccination against measles began in Portugal with VAS in 1973, with a campaign aimed at children up to 5 years old. In 1974 the vaccine was included in the PNV by administering a single dose at 12-15 months. In 1987 it was introduced into the PNV vaccination against parotitis (Mumps), and rubella, and these two vaccines administered in combination with measles vaccine in a trivalent vaccine, MMR. The MMR was administered as a single dose at 15 months, and the VAS vaccine began to be used only in special circumstances where it is necessary isolated measles immunization, such as in children less than 12 months in case of epidemic. In these cases remains the usual recommendation for the administration of MMR by 15 months.
The PNV 1990 introduced a 2nd dose of MMR to be administered at 11-13 years (for a theoretical discussion, see ref 21 ). In 1999 CTV reviewed the PNV and decreased age 2nd dose for 5-6 years with the aim of achieving higher immunization coverage.
At present, it is recommended to 1st dose of MMR at 15 months and, for those born after 1993, the 2nd dose at 5-6 years, before compulsory education. For infants to 1993 (inclusive) 2nd dose is given to 10-13 years of age.
In both sexes it is always a 2nd dose of MMR, regardless of age it was made the 1st dose of MMR or VAS. Between the two doses recommended a range of at least 2 months.
Peek here the impact of antibiotics and vaccination had on the number of deaths per year due to measles complications in Portugal.
Specific recommendations (DGS recommendations)
After age 18, women of childbearing age, with no previous dose of rubella vaccine (VAR or MMR) and whose immune status is unknown, should make one dose of MMR. The determination of antibodies against rubella is not required to make the decision to vaccinate.
The women not immunized or whose immune status is unknown, should also be vaccinated in the maternity or postpartum review consultation, not losing so vaccination opportunities .
Women of childbearing potential should be advised of the theoretical risk they run, if they are pregnant at the time of vaccination and if they become pregnant within three months, due mainly to the component against rubella.
The appearance of outbreaks of measles may warrant administration of a vaccine against measles - VAS (MMR the monovalent vaccine is not available) - from 6 to 11 months of age should keep the administration of the MMR by 15 months of R age.
The MMR I can be anticipated for the 12 months after an outbreak.
The measles vaccine can provide protection if administered within 72 hours after exposure to the measles virus, it is recommended vaccination with MMR or VAS to all susceptible individuals (ie no record of at least one dose of MMR and VAS or without credible previous history of measles) over 6 months and which have been contacted with measles cases.
Children with HIV positive, asymptomatic or symptomatic, without severe immunosuppression should make the MMR at 12 months of age (these children the MMR requires a prescription), followed by a second dose should be administered as early as possible (minimum interval 4 weeks from the first dose).
If measles exposure risk is high, vaccination should be carried out at an earlier age, between 6 and 9 months old, in which case it will make a new dose of MMR to 12 months and a booster four weeks later.
Measles (VAS or included in MMR)
In about 5-15% of cases may arise fever over 39,4ºC, starting between the 5th and the 12th day after vaccination. The disease usually takes 1 to 2 days (up to 5 days). In 5% of vaccinees may create transient rash, with or without fever.
Rubella vaccine (VAR or included in MMR)
The reactions normally associated with rubella vaccine are mild and rarely occur: rash, fever and lymphadenopathy, 5-12 days after vaccination. Occasionally, there may be transitional arthralgia in the small joints between 7 and 21 days after vaccination, especially in women from puberty.
Vaccine against mumps (included in MMR)
The most common local reactions, short, are burning, ulceration and / or skin irritation. Very rarely can arise mild allergic reactions (wheal or purple spot). General reactions attributed to the component against mumps are rare, registering occasional mild fever, lymphadenopathy, cough and rhinitis.
An anaphylactic reaction to egg history does not imply an anaphylactic reaction to the vaccines produced in cell cultures of chick embryo as is the case of some vaccines MMR and VAS.
However, and although unlikely to be an anaphylactic reaction following administration of these vaccines it is recommended that the same arises in hospitals.
In general, severe hypersensitivity to certain antibiotics contraindicate the use of vaccines that include in their composition.
VAS, VAR and MMR may contain neomycin, being in this case contraindicated in severe hypersensitivity conditions antibiotic.
Severe hypersensitivity to gelatin contraindicates some vaccines VAS, VAR and MMR, which contain this component.
Called attention to reading the leaflet of the vaccines and the Summary of Product Characteristics (SPC) in order to verify its composition. In severe cases of hypersensitivity to a substance that is part of the composition of a vaccine available in services may be considered the occasional use of a vaccine of another brand that is free of this substance.
Although no evidence of teratogenicity, live vaccines should not be given to pregnant women, mainly VAS, the VAR and the MMR.
In general, live vaccines (BCG, OPV, MMR) should not be administered to patients with:
- congenital immunodeficiency syndromes such as hipogamo-globulinémias or severe combined immunodeficiency;
- immunodepression states due to some malignancies, such lymphomas and other tumors of the reticulo-endothelial system and leukemias;
- immunosuppressive conditions associated with certain therapeutic. It must be ensured a minimum of 3 months after discontinuation of therapy to administer a live vaccine. The vaccination requires a prescription.
- immunosuppression states due to systemic therapy with corticosteroids at high doses (> = 2 mg / kg / day of prednisolone or 20 md / day for children weighing> 10 kg):
* for less than 14 days ( daily or on alternate days). Live vaccines may be administered immediately after stopping the treatment, but preferably after 2 weeks.
* for 14 days or more (daily or on alternate days). Live vaccines may be administered one month after stopping treatment.
- Organ transplants. After transplantation, they should not be administered live vaccines. Children over 12 months, should make the MMR at least one month before the transplant.
In the allogeneic and autologous bone marrow transplantation, as immunity induced by vaccination is lost after transplantation becomes necessary revaccination. The MMR administration is recommended two years after the transplant, unless the transplant recipients are the immunosuppressive therapy if they have had a relapse or if the host versus active donor disease.
Individuals with HIV-positive, asymptomatic or symptomatic, without severe immunosuppression, must comply with the immunization schedule of the PNV, but the MMR should be brought forward to 12 months of age (or exceptionally to 6-9 months of age).
Individuals with HIV positive, symptomatic and with severe immunosuppression may not receive any of the live vaccines of the PNV.
Following administration of vaccines against measles, mumps and rubella (VAS / VAR / MMR) must be ensured if a minimum of two weeks for administration of products containing immunoglobulins.
Following administration of products containing immunoglobulins, and in relation to measles, mumps and rubella, must be ensured a minimum of 3 months.
Vaccination of individuals who immunoglobulins or did transfusions were administered requires a prescription.
Effectiveness of vaccines - the case of mumps
The efficacy of measles and rubella components of MMR is quite high - it is estimated that 95% Ronde. The anti-mumps component (-papeira), however, raised some doubts in the mid-1990s Any decline in its effectiveness was associated with mumps epidemic recorded in 1996-1997 in Portugal. An explanation on this issue is appropriate. In 1987, the market existing MMR vaccines included three strains of mumps virus: Urabe Am9 (Japanese), Rubini (Switzerland) and Jeryl Lynn (USA). In Portugal, between 1987 and 1992, MMR vaccine were used with the three strains. However, following cases of post-vaccination encephalitis occurred in the United Kingdom, Canada and Japan, apparently related to the Urabe strain Am9, the Ministry of Health decided to purchase and administration of MMR with Urabe strain Am9 (Pluserix the vaccine) in October 1992. Like many other European countries from 1993 strain in use in national PNV has become almost exclusively the MMR with Rubini (Triviraten vaccine). This strain, however, was associated for several Portuguese authors to the rise in the number of mumps cases observed 2 or 3 years after the adoption of the Rubini strain, suggesting a significant decrease in effectiveness of the MMR component. There were similar outbreaks in other European countries and subsequent studies of vaccine efficacy, and abroad in Portugal, they suggested that, in fact, this is much smaller in Rubini than in other vaccine strains. At present, the MMR used in PNV national exclusively uses the Jeryl Lynn strain.
It is crucial to have high MMR vaccination coverage - the example of congenital rubella.
The diseases against which the MMR protects are generally benign when contracted early in life. However, the likelihood of such diseases originate serious complications tends to increase with age in which they are contracted. Examples include encephalitis caused by the measles, mumps orchitis following the, or the risk of congenital rubella syndrome (CRS) in the young in age who may become pregnant. If a pregnant young rubella, the virus can infect the fetus and cause a serious neurological disease in newborn known to SRC.
When betting on a vaccination strategy that aims to interrupt the circulation of these viruses through high immunization coverage rates, decreases greatly the likelihood of a person "find" the infectious agents from the moment it is born. Thus, the incidence of these diseases greatly lower, but the few reported cases occur in older ages than occurred in the days before vaccination. It will be shown mathematically that if the vaccine coverage is not sufficiently high (say,> 85%), although lower the absolute number of cases of disease, the proportion of these cases occurs in age increases very dangerous and, in the final balance there may be more cases with serious complications than there was before vaccination.
This undesirable effect of mass population vaccination is why certain industrialized countries which experience shows to be very difficult to achieve high vaccination coverage, they chose not to administer the MMR across the board. In the UK, for example, long been the rubella vaccine was not given to children and is only recommended for young women in pre-teens ages. The goal of vaccination, in this case, was not impede the movement of the virus but rather to prevent the onset cases of congenital rubella.
Mass vaccination with MMR therefore requires very high vaccination coverage (the complete safety is above 90%) and the reasoning can be generalized to diseases in which the risk of complications increases with age when they are contracted. The introduction of vaccines against these diseases always requires consideration of the danger of vaccine coverage are not high enough.