[Antibodies against vaccine-preventable diseases in pregnant women and their offspring. Measles, mumps, rubella, poliomyelitis, and varicella]

Seroprevalence of Measles-, Mumps-, and Rubella-specific antibodies in the German adult population - cross-sectional analysis of the German Health Interview and Examination Survey for Adults (DEGS1)

BACKGROUND

The WHO European Region targets the elimination of measles, rubella, and the congenital rubella syndrome and welcomes mumps elimination via the joint MMR vaccine. In a push towards this elimination goal, Germany introduced a recommendation on MMR vaccination for adults in 2010 to prevent increasing numbers of measles cases among adults and to strengthen herd immunity.

METHODS

The prevalence of anti-measles, -mumps, and -rubella IgG antibodies was analysed in 7,115 participants between the ages of 18 and 79 years in the German Health Interview and Examination Survey. Risk factors of seronegativity of adults born 1970 or later were determined.

FINDINGS

The seroprevalence of anti-measles IgG antibodies was more than 97% in adults born before 1965 and less than 90% in adults born afterwards. Prevalence and GMTs declined with later years of birth. Seronegativity was associated with two-sided migration background and region of residence in East Germany. For anti-mumps IgG antibodies, the seroprevalence was less than 90% in almost all age groups. Prevalence and GMTs declined with later years of birth. Seronegativity was not associated with any socio-demographic factor. Anti-rubella IgG seropositivity was found in more than 90% of adults born before 1985. GMTs declined in younger age groups. Seronegativity was associated with birth between 1980 and 1993 and male gender. High socio-economic status lowered the odds of being seronegative.

INTERPRETATION

These data reinforce the implementation of the vaccination recommendation for adults and provide the basis for further evaluation of this measure.

FUNDING

The Federal Ministry of Health, Germany.

Estimation of the burden of varicella in Europe before the introduction of universal childhood immunization

BACKGROUND

Varicella is generally considered a mild disease. Disease burden is not well known and country-level estimation is challenging. As varicella disease is not notifiable, notification criteria and rates vary between countries. In general, existing surveillance systems do not capture cases that do not seek medical care, and most are affected by underreporting and underascertainment. We aimed to estimate the overall varicella disease burden in Europe to provide critical information to support decision-making regarding varicella vaccination.

METHODS

We conducted a systematic literature review to identify all available epidemiological data on varicella IgG antibody seroprevalence, primary care and hospitalisation incidence, and mortality. We then developed methods to estimate age-specific varicella incidence and annual number of cases by different levels of severity (cases in the community, health care seekers in primary care and hospitals, and deaths) for all countries belonging to the European Medicines Agency (EMA) region and Switzerland.

RESULTS

In the absence of universal varicella immunization, the burden of varicella would be substantial with a total of 5.5 million (95% CI: 4.7-6.4) varicella cases occurring annually across Europe. Variation exists between countries but overall the majority of cases (3 million; 95% CI: 2.7-3.3) would occur in children <5 years. Annually, 3-3.9 million patients would consult a primary care physician, 18,200-23,500 patients would be hospitalised, and 80 varicella-related deaths would occur (95% CI: 19-822).

CONCLUSIONS

Varicella disease burden is substantial. Most cases occur in children <5 years old but adults require hospitalisation more often and are at higher risk of death. This information should be considered when planning and evaluating varicella control strategies. A better understanding of the driving factors of country-specific differences in varicella transmission and health care utilization is needed. Improving and standardizing varicella surveillance in Europe, as initiated by the European Centre for Disease Prevention and Control (ECDC), is important to improve data quality to facilitate inter-country comparison.

Microbiology laboratory and the management of mother-child varicella-zoster virus infection

Varicella-zoster virus, which is responsible for varicella (chickenpox) and herpes zoster (shingles), is ubiquitous and causes an acute infection among children, especially those aged less than six years. As 90% of adults have had varicella in childhood, it is unusual to encounter an infected pregnant woman but, if the disease does appear, it can lead to complications for both the mother and fetus or newborn. The major maternal complications include pneumonia, which can lead to death if not treated. If the virus passes to the fetus, congenital varicella syndrome, neonatal varicella (particularly serious if maternal rash appears in the days immediately before or after childbirth) or herpes zoster in the early years of life may occur depending on the time of infection. A Microbiology laboratory can help in the diagnosis and management of mother-child infection at four main times: (1) when a pregnant woman has been exposed to varicella or herpes zoster, a prompt search for specific antibodies can determine whether she is susceptible to, or protected against infection; (2) when a pregnant woman develops clinical symptoms consistent with varicella, the diagnosis is usually clinical, but a laboratory can be crucial if the symptoms are doubtful or otherwise unclear (atypical patterns in immunocompromised subjects, patients with post-vaccination varicella, or subjects who have received immunoglobulins), or if there is a need for a differential diagnosis between varicella and other types of dermatoses with vesicle formation; (3) when a prenatal diagnosis of uterine infection is required in order to detect cases of congenital varicella syndrome after the onset of varicella in the mother; and (4) when the baby is born and it is necessary to confirm a diagnosis of varicella (and its complications), make a differential diagnosis between varicella and other diseases with similar symptoms, or confirm a causal relationship between maternal varicella and malformations in a newborn.

Prevalence of anti-rubella, anti-measles and anti-mumps IgG antibodies in neonates and pregnant women in Catalonia (Spain) in 2013: susceptibility to measles increased from 2003 to 2013

Non-immune neonates and non-immune pregnant women are at risk of developing rubella, measles and mumps infections, including congenital rubella syndrome. We describe the seroepidemiology of measles, mumps and rubella (MMR) in neonates and pregnant women in Catalonia (Spain). Anti-rubella, anti-measles and anti-mumps serum IgG titres were assessed using enzyme-linked immunosorbent assay (ELISA) tests in 353 cord blood samples from neonates of a representative sample of pregnant women obtained in 2013. The prevalence of protective antibody titres in neonates was 96 % for rubella IgG (≥8 IU/ml), 90 % for measles IgG (>300 IU/ml) and 84 % for mumps IgG (>460 EU/ml). Slightly lower prevalences of protective IgG titres, as estimated from the cord blood titres, were found in pregnant women: 95 % for rubella IgG, 89 % for measles IgG and 81 % for mumps IgG. The anti-measles and anti-mumps IgG titres and the prevalences of protective IgG titres against measles and mumps increased significantly (p < 0.001) with maternal age. The prevalence of protective anti-measles IgG titres decreased by 7 % [odds ratio (OR) = 0.15, p < 0.001), the prevalence of protective anti-rubella IgG titres increased by 3 % (OR = 1.80, p < 0.05) and the MMR vaccination coverage (during childhood) in pregnant women increased by 54 % (OR = 2.09, p < 0.001) from 2003 to 2013. We recommend to develop an MMR prevention programme in women of childbearing age based on mass MMR vaccination or MMR screening and vaccination of susceptible women to increase immunity levels against MMR.

A seroprevalence survey on varicella among adults in the vaccination era in Apulia (Italy)

In 2006, the Apulia Region (Italy) introduced universal routine vaccination (URV) against varicella disease. The coverage for one dose of varicella vaccine at 24 month of age reached 91.1% in 2010 birth-cohort. Vaccination coverage for the second dose at 5-6 years was 64.8% for the cohort 2005, and 28.8% for adolescents born in 1997. The aim of the present study is to evaluate the pattern of immunity/susceptibility to varicella in Apulian adults by a seroprevalence survey carried out 6 years after the introduction of URV. The study was carried out from May 2011 to June 2012 among blood donors of the Department of Transfusion Medicine of Policlinico General Hospital in Bari. Subjects were enrolled by a convenience sample. For each enrolled patient we collected a sample of serum of 5 ml. Anti-VZV IgG in collected sera were analyzed by chemiluminescence (CLIA). We enrolled 1769 subject; 1365 (77.2%) were male with a mean age of 38.4 ± 11.7 years. 93% (95% CI=91.7-94.1) of enrolled subject presented a titre of anti-VZV IgG >164 mIU/mL. GMT of anti-VZV IgG titre was 1063.4 mIU/ml and no difference was observed between different age group. According to our data, URV did not seem to have any impact on susceptibility among adults and in particular we did not note any cluster of susceptible subjects among young adults. Also in the vaccination era, we did not note that the average age of infection shifts among adults and then we could exclude an increase of case of complicated varicella related to the URV.

Seroprevalence of anti-rubella and anti-measles IgG antibodies in pregnant women in Shiraz, Southern Iran: outcomes of a nationwide measles-rubella mass vaccination campaign

Objective

Nonimmune pregnant women are at risk of developing congenital rubella syndrome and measles complications. We aimed to identify pregnant women susceptible to rubella or measles in order to determine the need for immunity screening and supplemental immunization in women of childbearing age.

Method

This seroprevalence survey was conducted by convenience sampling in obstetric hospitals affiliated with Shiraz University of Medical Sciences (southern Iran). Serum IgG levels were measured by ELISA.

Result

Mean age of the 175 pregnant women was 27.3±5.3 (range 16 to 42) years. The geometric mean concentration of anti-rubella IgG was 14.9 IU/mL (CI 95%,14.1–15.5), and that of anti-measles IgG was 13.8 IU/mL (CI 95%, 13–14.5). One hundred sixty-eight women (96%) had a protective serologic level (>11 IU/mL) of IgG against rubella, and 143 (81.7%) had a protective level against measles. Except for a significant inverse correlation that was showed by univariate analysis between anti-rubella IgG and the women’s age (P = 0.01), immunity did not correlate with demographic or obstetric characteristics or medical history. There was no significant correlation between anti-rubella and anti-measles IgG levels (P = 0.25).

Conclusion

Nearly a decade after Iran’s nationwide measles-rubella vaccination campaign for the population aged 5–25 years, most pregnant women up to 34 years of age had humoral immunity against rubella. We recommend rubella immunity screening or catch-up immunization for women older than 35 years who wish to become pregnant, and measles immunity screening and appropriate vaccination for all women of childbearing age.

[Seroprevalence of antibodies against infectious pathogens relevant to pregnancy among healthcare workers]

Healthcare workers (HCWs) are exposed to infectious diseases throughout the course of their work. The concerns of pregnant HCWs are considerable because certain otherwise mild infections may affect fetal development. We studied 424 pregnant HCWs at the University Hospital Frankfurt between March 2007 and July 2011. Serological tests were carried out for varicella zoster virus (VZV), measles, mumps, rubella (MMR), cytomegalovirus (CMV) and parvovirus B19. Our overall seroprevalence data with regard to VZV, MMR, CMV and parvovirus B 19 corresponded to the general population. However, physicians demonstrated lower seroprevalence towards the two non-vaccine-preventable diseases (CMV: 37.5% [KI 27.4-48.5]; parvovirus B19: 69.3% [KI 58.6-78.7]) compared with nurses (CMV: 53.4% [KI 46.1-60.6], parvovirus B19: 75.1% [68.4-81.1]). It was striking that, only one in five of the study population showed IgG antibodies against all of the six pregnant-relevant viral diseases tested, of the physicians as few as one in six. A routine exclusion from the workplace due to non-immunity would mean that it would not be possible to employ the majority of pregnant staff in healthcare and childcare.

Susceptibility to varicella-zoster among pregnant women in the province of Lecce, Italy

BACKGROUND

Varicella is predominantly a childhood disease, considered a mild self-limiting disease that can have serious complications for a pregnant woman and her developing fetus.

OBJECTIVES

We investigated the susceptibility to varicella-zoster Virus (VZV) among pregnant women in the province of Lecce.

STUDY DESIGN

A cross-sectional study was carried out in Departments of Gynecology and Obstetrics of the Province of Lecce, where 539 pregnant women were recruited, and face-to-face interviews were conducted. Varicella IgG tests were performed.

RESULTS

The prevalence of varicella susceptibility among pregnant mothers was 10.6%. The prevalence of IgG antibodies increases significantly with increasing age, from 62.5% in the age group 15-19 years to 94.4% in the age group 40-49 years.

DISCUSSION

In the Italian National Vaccination Plan 2005-2007, varicella vaccine is only recommended for childbearing women. A safe and effective vaccine is available and no abnormalities have been observed among infants born to susceptible women who received varicella vaccines during pregnancy. Such a high number of susceptible women indicates that preventive and informative programs should be introduced, even among those who do not plan to become pregnant. Routine counselling, varicella IgG antibody screening and varicella vaccination should be considered if they have no history of the infection, to reduce the risk of fetal complications and the cost of healthcare associated with the infection.

Prevalence of varicella-zoster antibodies in pregnant women in Catalonia (Spain). Rationale for varicella vaccination of women of childbearing age

OBJECTIVE

The objective of this study was to determine the prevalence of antibodies against varicella-zoster virus (VZV) in pregnant women in Catalonia (Spain).

SETTING

The prevalence of antibodies against VZV was assessed in a representative sample (n = 1522) of pregnant women of Catalonia obtained in 2003.

METHOD

The sample was obtained including all women attended for childbirth, during 2 months of 2003, in 27 randomly selected hospitals with maternity clinics.

MAIN OUTCOME MEASURES

Varicella-zoster antibodies were determined using the enzyme-linked immunosorbent assay test.

RESULTS

The total number of women included in the study was 1522, corresponding to a participation rate of 83%. The prevalence of varicella-zoster antibodies in pregnant women was 96.1% (95% CI 95.1-97.1). The prevalence of antibodies was 94% in pregnant women aged 15-24 years, 95% in those aged 25-29 years and >95% in those aged 30-49 years. The prevalence of antibodies was not associated to the place of birth, place of residence (urban or rural), educational level and social class. The study showed that 6% of pregnant women aged 15-24 years and 5% of those aged 25-29 years were susceptible to varicella-zoster infections in Catalonia (Spain).

CONCLUSION

The study showed that a varicella-zoster vaccination programme aimed at women of childbearing age could be necessary in Catalonia to prevent all varicella-zoster infections during pregnancy.

Rubéola: el nuevo escenario de una vieja enfermedad

World Health Organization has the target by the year 2010 of reducing congenital rubella syndrome to less than 1/100,000 live births, being necessary the control of the virus circulation. Rubella is currently a low-incidence disease, that affected to children in the pre-vaccine era. The excellent measles-mumps-rubella vaccine coverage in children, together with the vaccination campaigns in childbearing age women, leads to get very high protection. Until recently, susceptible individuals were grouped in a reduced fraction of young men, born after the decline of wild virus circulation and that did not receive the vaccine, due to its age. The new demographic situation derived from the immigration is causing important changes in the susceptibility pattern. Many immigrants came to Spain from regions where rubella vaccine is not (or until recently was not) administered; as result, it can emerge an accumulation of susceptible individuals (especially among adults) allowing the re-circulation of the virus.

Abort- und Frühgeburtenrate nach akuter Mumpsinfektionin der Schwangerschaft

OBJECTIVE

Since mumps infection is endemic, the occurrence of acute mumps infection during pregnancy is rare. As a result, data on the possible negative consequences of acute mumps infection on pregnancy outcome are limited.

PATIENTS AND METHODS

The clinical diagnosis of acute mumps infection was serologically confirmed in 79 pregnant women between January 1985 and December 2002. Data on pregnancy outcome were obtained from the gynaecologist or obstetrician. Cord blood from 26 of the 57 live-born infants was investigated for mumps-specific IgM and IgG antibodies by enzyme-linked immunoassay.

RESULTS

Sixty-two patients were prospectively followed up with respect to pregnancy outcome. Two of the 62 pregnancies were electively terminated. The overall rate of fetal loss was 6.6% (4/60). Only 2 cases of spontaneous abortion occurred during the first trimester. However, all 4 spontaneous abortions occurred in women who had contracted mumps infection during the first trimester. The time interval between mumps infection and fetal loss varied widely. The median gestational age at delivery was 40 weeks. Only 2 of the 57 live-born infants (3.5%) were delivered before completion of the 37th week of pregnancy. Mumps-specific IgM anti-bodies were not detected in any of the 26 cord blood samples tested.

CONCLUSION

The lack of mumps-specific antibodies in the cord blood samples tested suggests that prenatal mumps infection did not occur. The frequency of premature birth and spontaneous abortion following mumps infection in pregnancy does not appear to be increased over normal levels.