Correlates of protection against rotavirus infection and
disease.
Offit PA.
Children's Hospital of Philadelphia, 34th St. and Civic Center Blvd., USA.
Repeated infections with the 'mucosal' pathogen rotavirus are common in
children. Subsequent rotavirus infections usually cause milder symptoms than
first-time infections. Therefore, although natural rotavirus infection
attenuates the severity of subsequent infections, it does not prevent
reinfection or mild disease. On the
other hand, natural infection with 'systemic' viruses such as measles, mumps,
rubella, or varicella
often confers life-long protection against mild disease associated with
reinfection. The degree to which differences in the pathogenesis of
systemic and mucosal pathogens determines differences in the capacity of
natural infection to induce life-long protective immunity will be discussed.
This paradigm will be used to explore the immunological effector functions
associated with protection against rotavirus challenge.
[Epidemiological analysis of immunity against
vaccine-preventable diseases: rubella, measles, mumps and chickenpox]
[Article in German]
Buxbaum S, Doerr HW, Allwinn R.
Institut fur Medizinische Virologie der Universitatsklinik Frankfurt/Main,
Germany. S.Buxbaum@em.uni-frankfurt.de
BACKGROUND AND OBJECTIVE: Measles,
mumps, rubella and varicella
zoster virus (VZV)
infections are regarded as typical diseases of childhood: They are normally
clinically mild and result in lifelong immunity. Severe clinical
disease is known in immunocompromised patients; rubella virus infections
during pregnancy often result in congenital rubella syndrome. All these
diseases are preventable by vaccination which is recommended in Germany,
recently vaccination against VZV for teenager without immunity since July
2001. In the following study we screened for immunity against the four
viruses. PATIENTS AND METHODS: Serum samples were obtained at the Institute of
Medical Virology Frankfurt/Main from January 1999 until December 2000. We
tested for specific antibodies against measles (n = 915), against mumps (n =
857), against rubella (n = 1886) and against VZV (n = 2291). Seroprevalences
were determined in different age groups. RESULTS: Altogether the highest rate
of seronegatives is detected in younger children. VZV-seronegativity rates
decrease from 74 % to 32 % in younger children. Against rubella also in this
age group rate of seronegatives is found in 40 % and less than 10 % by
teenagers. From this age group also immunity against rubella is found
approximately in 80 % of seropositives. CONCLUSIONS: The following study shows
that high seronegative rates are detectable, and here specially against VZV-specific
antibodies. For seronegative teenagers, vaccination against VZV is now
recommended in Germany. Immunization rates of at least 95 % in childhood would
be effective in avoiding severe courses of disease and giving protection in
pregnancy.
Seroepidemiological study of respiratory syncytial virus in
Sao Paulo state, Brazil.
Cox MJ, Azevedo RS, Cane PA, Massad E, Medley GF.
Department of Biological Sciences, University of Warwick, United Kingdom. cox@oikos.warwick.ac.uk
Transmission of respiratory syncytial virus is thought to be highly seasonal
based on reported clinical cases, although transmission resulting in mild
disease in all age groups has been little studied. This has been investigated
in a seroepidemiological survey using sera from Sao Paulo, Brazil.
Seroprevalence was found to increase rapidly with age, reaching over 90% by
three years of age. This is typical of
viral infections, which produce life-long immunity following primary
infection. One-hundred percent seropositivity was attained by five
years of age and maintained throughout adulthood, whereas mean antibody titers
continued to increase with age. The mean duration of maternal antibodies was
estimated to be 3.3 months with antibody decay demonstrated in paired samples
from infants. The results are discussed in relation to possible mechanisms
generating such a profile.
Rubella among the Amish: resurgent disease in a highly
susceptible community.
Briss PA, Fehrs LJ, Hutcheson RH, Schaffner W.
Division of Field Epidemiology, Centers for Disease Control, Atlanta, GA.
Although the Amish make up less than 0.05% of the United States population,
nearly all rubella reported in the United States in 1991 occurred in this
population. In early 1991 a large rubella outbreak in a Tennessee Amish
community that had experienced no rubella for 17 years afforded an opportunity
to describe the epidemiology of rubella in this unique population. Structured
interviews were conducted with 54 Amish families. Of 383 persons in the sample
85 (22%) had rubella. Illnesses were mild; 16% of cases lacked fever and 20%
of cases reported no symptoms except rash. Children < 17 years of age were 7
times more likely than older individuals to be affected (77 of 214 vs. 8 of
165). All pregnant women in the community were > 20 years of age; none
developed rubella. No congenital rubella syndrome was recognized. Although
rubella is increasingly a disease of adolescents and young adults, in this
outbreak, rubella was again a childhood disease. Illness in this
community-based investigation was mild; rubella may be difficult to diagnose
and report. Immunity after remote
natural infection was durable since the community's last outbreak.
Pregnant women probably were protected by the age distribution of immunity;
this age distribution may not occur in other Amish populations. If preventable
morbidity from rubella and other vaccine preventable diseases is to be avoided
in this group, increased attention should be directed to encouraging
vaccinations among Amish persons.
Persistence of vaccine-induced immune responses to rubella:
comparison with natural infection.
Horstmann DM, Schluederberg A, Emmons JE, Evans BK, Randolph MF, Andiman
WA.
Serologic responses and patterns of antibody persistence in children given
HPV-77 DE-5 or RA27/3 vaccine were compared with those in children who had
experienced natural infection. The results indicated that both vaccines induce
long-lasting immunity in most individuals. RA27/3 vaccine proved more
immunogenic and resulted in higher antibody titers; after 11 years 95% of
those who seroconverted who were tested had hemagglutination-inhibiting (HAI)
antibodies and 100% had neutralizing (NT) antibodies. Titers in HPV-77 DE-5
vaccinees were lower, and in 16% of those whose immune responses were feeble,
HAI titers decreased to less than 1:8 after nine to 12 years; however, when
their sera were examined by the more sensitive latex-agglutination test, all
but two were found to have specific rubella antibody at levels of 1:1 to 1:16.
Natural infection with wild virus was
shown to induce more vigorous immune responses than did either vaccine:
antibody titers were higher, decreases were smaller, and none fell to less
than 1:8 (HAI)
or less than 1:4 (NT).
Subclinical rubella reinfection in pregnancy: report of a
case.
Chen FP, Chu KK.
Department of Obstetrics and Gynecology, Keelung Chang Gung Memorial Hospital,
Taiwan, R.O.C.
A G1 PO, 25-year-old woman, who was confirmed to have a natural immunity to
rubella before pregnancy, was found to have rubella reinfection with positive
rubella IgM antibody at seven weeks of gestation. At 23 weeks' gestation, she
received fetal cordocentesis in which fetal blood tests were negative for
rubella-specific IgM. There were also nonspecific findings in detailed
sonographic examination. Thereafter, she delivered a healthy, female baby at
term. Rubella IgM was not detected in the infant blood at birth and IgG
subsided after the first year of life.
A primary attack of rubella does not always indicate lifelong immunity;
reinfection can occur. Although the symptoms of rubella reinfection are
mild and the risk to the fetus from maternal rubella reinfection during
pregnancy seems to be lower than that of a primary attack, prenatal evaluation
of intrauterine infection by cordocentesis after 23 weeks' gestation should be
considered.
PMID: 8102288 [PubMed - indexed for MEDLINE]
AN: 93350468
Here is a case where immunity was not lifelong. - SM
[Rubella infection in pregnancy in naturally acquired
immunity]
[Article in German]
Klein M, Rosen A, Beck A, Hofmann H.
Geburtshilflich-gynakologische Abteilung des Hanusch-Krankenhaus, Wien.
This case-report concerns the problem of rubella-reinfection in pregnancy
(17th week of gestation). In spite of
documented maternal immunity infection was followed by transmission of virus
to the fetus. Nowadays in most countries antenatal maternal screening
for rubella seems to be sufficient. The observation of cutaneous exanthema,
however, demands further investigation, even if maternal immunity was
documented.
PMID: 2763610 [PubMed - indexed for MEDLINE]
And another. Perhaps, as appears to be the case
with measles and chickenpox, repeated
exposure is required. - SM
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MATERIAL CONTAINED, PRESENTED, OR PROVIDED HERE IS FOR GENERAL INFORMATION
PURPOSES ONLY AND IS NOT TO BE CONSTRUED AS REFLECTING THE KNOWLEDGE OR OPINIONS
OF THE PUBLISHER, AND IS NOT TO BE CONSTRUED OR INTENDED AS PROVIDING MEDICAL OR
LEGAL ADVICE. THE DECISION WHETHER OR NOT TO VACCINATE IS AN IMPORTANT AND
COMPLEX ISSUE AND SHOULD BE MADE BY YOU, AND YOU ALONE, IN CONSULTATION WITH
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