Newsgroup: it.scienza.medicina
Titolo: rosolia e immunizzazione

Chiedo a qualche medico del NG di chiarirmi un dubbio venutomi in un
thread precedente: cosa dovrebbe fare, prima di programmare una
gravidanza, una donna che non ha mai avuto la rosolia, ma che e' stata
vaccinata intorno all'eta' di dieci anni (ossia, una ventina d'anni
prima)? Ripetere il vaccino? Far finta di nulla? Altro?...
ciao
Lisa

Lisa ha scritto:
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In attesa che qualche medico ti risponda specificamente, e ricordandoti
che la medicina non è una scienza esatta in cui basti applicare teoremi
e scrivere equazioni differenziali per arrivare a una soluzione esatta,
segnalo questi abstract correlati al tuo quesito (rubella = rosolia).
  [1] Prim. Care Update Ob Gyns 2001 Jul;8(4):133-137
 Rubella.
 Signore C.
 , Falls Church, Virginia, USA
  Rubella, also known as German measles or three-day measles, is a
 self-limited, mild viral illness that poses little danger to children or
 adults. For the developing fetus, however, infection with rubella virus
 is a grave threat, capable of inducing severe anomalies and permanent
 disability. Despite widespread vaccination programs, populations of
 susceptible individuals persist, among them women of childbearing age
 whose pregnancies remain vulnerable to congenital rubella syndrome.
 In the United States, the currently used rubella vaccine employs
 live-attenuated virus and is contraindicated in pregnancy. Nonpregnant
 women receiving rubella vaccination should be advised to use effective
 contraception for 3 months after inoculation. These warnings persist
 despite the fact that no clinically significant case of congenital rubella
 syndrome after maternal vaccination has been reported. Obstetrician/
 gynecologists must be familiar with rubella and the management of
 pregnancies complicated by exposure to the disease. Furthermore,
 practitioners must actively seek and vaccinate susceptible individuals
 to minimize this significant threat to public health.
 PMID: 11435119
  [2] Epidemiol Infect 2000 Dec;125(3):617-34
 Modelling rubella in Europe.
 Edmunds WJ, van de Heijden OG, Eerola M, Gay NJ.
 Immunisation Division, PHLS Communicable Disease Surveillance Centre,
 London, United Kingdom.
  The prevention of congenital rubella syndrome (CRS), as a complication of
 rubella infection during pregnancy, is the main aim of rubella vaccination
 programmes. However, as vaccination of infants leads to an increase in the
 average age at which those who were not immunized become infected, certain
 rubella vaccination programmes can lead to an increase in the incidence of
 CRS. In this paper we use a mathematical model of the transmission dynamics
 of rubella virus to investigate the likely impact of different vaccination
 policies in Europe. The model was able to capture pre- and post-vaccination
 patterns of infection and prevalence of serological markers under a wide
 variety of scenarios, suggesting that the model structure and parameter
 estimates were appropriate. Analytical and numerical results suggest that
 endemic circulation of rubella is unlikely in Finland, the United Kingdom,
 The Netherlands, and perhaps Denmark, provided vaccine coverage is uniform
 across geographical and social groups. In Italy and Germany vaccine coverage
 in infancy has not been sufficient to interrupt rubella transmission,
 and continued epidemics of CRS seem probable. It seems unlikely that the
 immunization programmes in these countries are doing more harm than good,
 but this may be partly as a result of selective immunization of schoolgirls.
 Indeed, in both these countries, selective vaccination of schoolgirls with
 inadequate vaccination histories is likely to be an important mechanism
 by which CRS incidence is suppressed (unlike the other countries, which
 have had sufficiently high infant coverage rates to withdraw this option).
 Reducing inequalities in the uptake of rubella vaccine may bring greater
 health benefits than increasing the mean level of coverage.
 PMID: 11218213
  [3] Vaccine 2000 Jul 15;18(27):3106-12
 Duration of rubella immunity induced by two-dose measles, mumps and
 rubella (MMR) vaccination. A 15-year follow-up in Finland.
 Davidkin I, Peltola H, Leinikki P, Valle M.
 National Public Health Institute, Helsinki, Finland. 
irja.d...@ktl.fi
  A national two-dose vaccination program with a combined measles, mumps
 and rubella (MMR-II) vaccine was introduced in Finland, in 1982, immunizing
 children at the ages of 14-18 months and 6 years. Antibody levels were
 determined from serial samples from a group of originally 350 children
 during 15 years. The latest samples were taken 15.5 years after the first
 vaccination and 70% of the children could still be reached. The aim of this
 study was to determine the kinetics of rubella antibodies induced by the
 MMR-II vaccine in these individuals. Rubella antibodies were analyzed from
 three different cohorts: Group I seronegative children (n=166) vaccinated
 at 14-18 months and 6 years, Group II seronegative children (n=139) and
 Group III seropositive children (n=16) vaccinated at 6 and 11-13 years.
 Samples collected 0-9 years after vaccination were analyzed by hemolysis-
 in-gel (HIG) and later samples by enzyme immunoassay (EIA) techniques.
 The primary vaccination induced 100% seropositivity in vaccinees with
 a mean zone diameter of 10 (+/-1.3), 10.2 (+/-1.1) and 11.5 (+/-0.9) mm,
 in Groups I, II and III, respectively. The seropositivity rate was still
 high at 15 years, 99%, 100% and 100% with the geometric mean titer 23, 46
 and 105 IU/ml, respectively. At 15 years, antibody levels <15 IU/ml which
 is the suggested protective level, were found in 31, 9 and 0% of children
 in Groups I, II and III, respectively. Because almost a third of the
 individuals in Group I now, at the age of 17 years, had low levels of
 rubella antibodies, it is possible that rubella infections may re-emerge
 during pregnancy. A careful surveillance including serological follow-up
 is therefore very important.
 PMID: 10856790
  [4] J Infect 2000 Sep;41(2):187-9
 Clinical rubella reinfection during pregnancy in a previously vaccinated
 woman.
 Aboudy Y, Barnea B, Yosef L, Frank T, Mendelson E.
 Central Virology Laboratory, Public Health Services, Ministry of Health
 and The Chaim Sheba Medical Center, Tel-Hashomer, 52621, Israel.
  We report a documented case of clinically apparent rubella reinfection
 during pregnancy with rubelliform rash and fever followed by lymphodenopathy
 at the 18th week of gestation, in a previously vaccinated woman with
 haemagglutination inhibition (HI) antibody titre of 1:32. The serological
 tests results (including neutralizing antibodies) demonstrated a significant
 rise in her rubella specific IgG level with strongly positive IgM
 reactivity. In addition, rubella-specific IgG antibody avidity testing
 displayed high avidity index (53-88%) typical of rubella reinfection.
 Umbilical cord blood, drawn by sonographic-guided cordocentesis at 24 weeks'
 gestation, was found to be negative for rubella-specific IgM antibody.
 The pregnancy was continued to term, and a healthy infant was born.
 PMID: 11023770
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...
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:-))
Fare un richiamo dopo aver effettuato un dosaggio delle IgG
specifiche. C'è da tener conto che la presenza di anticorpi
passivamente indotti da una vaccinazione può rendere parzialmente o
totalmente inefficace il richiamo stesso ("avidità" antigenica). Il
richiamo dovrebbe essere effettuato almeno 3 mesi prima dell'eventuale
concepimento (per evitare rischi usare opportuni mezzi
anticoncezionali).
Bye
Docpocket