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Featured researches published by Maija Lappalainen.


American Journal of Obstetrics and Gynecology | 1999

Treatment of toxoplasmosis during pregnancy: A multicenter study of impact on fetal transmission and children’s sequelae at age 1 year ☆ ☆☆ ★

Walter Foulon; Isabelle Villena; Babill Stray-Pedersen; Anne Decoster; Maija Lappalainen; Jean-Michel Pinon; Pål A. Jenum; Klaus Hedman; Anne Naessens

OBJECTIVE Toxoplasmosis during pregnancy can cause fetal infection, with unpredictable sequelae in later life. We measured the effects of prenatal antibiotic therapy on the fetomaternal transmission of Toxoplasma gondii and on the appearance of sequelae in the congenitally infected child at age 1 year. STUDY DESIGN In a multicenter study we investigated consecutive women with Toxoplasma seroconversion during pregnancy. Data were obtained from 144 women recruited in 5 different Toxoplasma reference centers. Through multivariate analysis we assessed the association between transmission and appearance of sequelae as a function of the following parameters: estimated gestational age at infection, administration of antibiotic therapy, duration of antibiotic therapy, and time lapse between infection and the start of antibiotic therapy. RESULTS Sixty-four of the 144 women (44%) gave birth to a congenitally infected infant. Multivariate analysis showed that transmission was predicted neither by whether antibiotics had been administered nor by the time lapse between infection and the start of antibiotic therapy, but only by the gestational age at which maternal infection occurred (P <.0001). Sequelae were found in 19 children (13%), 9 of whom (6%) had severe sequelae. Administration of antibiotics was predictive of the absence of sequelae (P =.026, odds ratio 0.30, 95% confidence interval 0.104-0.863), in particular the absence of severe sequelae (P =.007, odds ratio 0.14, 95% confidence interval 0.036-0.584). The sooner antibiotics were given after the infection, the less frequently sequelae were seen (P =. 021). CONCLUSION Prenatal antibiotic therapy after toxoplasmosis during pregnancy had no impact on the fetomaternal transmission rate but reduced the rate of sequelae among the infected infants. The early start of treatment resulted in a significant reduction in the number of severely affected infants.


Epidemiology and Infection | 2011

Rotavirus genotypes co-circulating in Europe between 2006 and 2009 as determined by EuroRotaNet, a pan-European collaborative strain surveillance network

Miren Iturriza-Gomara; T. Dallman; Krisztián Bányai; Blenda Böttiger; Javier Buesa; Sabine Diedrich; Lucia Fiore; K. Johansen; Marion Koopmans; Neli Korsun; D. Koukou; A. Kroneman; Brigitta László; Maija Lappalainen; Leena Maunula; A. Mas Marques; Jelle Matthijnssens; Sofie Midgley; Zornitsa Mladenova; Sameena Nawaz; Mateja Poljšak-Prijatelj; P. Pothier; Franco Maria Ruggeri; Alicia Sánchez-Fauquier; Andrej Steyer; I. Sidaraviciute-Ivaskeviciene; V. Syriopoulou; A. N. Tran; Vytautas Usonis; M. Van Ranst

EuroRotaNet, a laboratory network, was established in order to determine the diversity of co-circulating rotavirus strains in Europe over three or more rotavirus seasons from 2006/2007 and currently includes 16 countries. This report highlights the tremendous diversity of rotavirus strains co-circulating in the European population during three years of surveillance since 2006/2007 and points to the possible origins of these strains including genetic reassortment and interspecies transmission. Furthermore, the ability of the network to identify strains circulating with an incidence of ≥1% allowed the identification of possible emerging strains such as G8 and G12 since the beginning of the study; analysis of recent data indicates their increased incidence. The introduction of universal rotavirus vaccination in at least two of the participating countries, and partial vaccine coverage in some others may provide data on diversity driven by vaccine introduction and possible strain replacement in Europe.


American Journal of Obstetrics and Gynecology | 1999

Prenatal diagnosis of congenital toxoplasmosis: A multicenter evaluation of different diagnostic parameters☆☆☆★

Walter Foulon; Jean-Michel Pinon; Babill Stray-Pedersen; Arnold Pollak; Maija Lappalainen; Anne Decoster; Isabelle Villena; Pål A. Jenum; Michael Hayde; Anne Naessens

OBJECTIVE Our purpose was to evaluate different methods of diagnosing congenital toxoplasmosis prenatally by amniocentesis and cordocentesis. STUDY DESIGN In a retrospective multicenter study, we investigated consecutive women who had seroconversion for Toxoplasma gondii during pregnancy and who underwent either amniocentesis or cordocentesis or both to obtain a prenatal diagnosis of fetal toxoplasmosis. Data were obtained from 122 patients recruited in 6 different European Toxoplasma reference centers. Infants born to these mothers were followed up until 1 year of age to confirm or exclude congenital toxoplasmosis. Sensitivity, specificity, positive predictive value, and negative predictive value were measured for the following parameters: (1) detection of the parasite in amniotic fluid by mouse inoculation, (2) detection of the parasite in amniotic fluid by in vitro cell culture, (3) detection of Toxoplasma deoxyribonucleic acid in amniotic fluid by a polymerase chain reaction assay, (4) detection of the parasite in fetal blood by mouse inoculation, (5) detection of specific immunoglobulin M antibodies in fetal blood, and (6) detection of specific immunoglobulin A antibodies in fetal blood. RESULTS The polymerase chain reaction test performed on amniotic fluid had the highest level of sensitivity (81%) and also a high level of specificity (96%). The combination of the polymerase chain reaction test and mouse inoculation of amniotic fluid increased sensitivity to 91%. The sensitivity of immunoglobulins M and A in fetal blood was 47% and 38%, respectively. In congenitally infected fetuses a negative correlation was observed between positive serologic parameters and gestational age at the time of maternal infection and at prenatal diagnosis. CONCLUSION Congenital toxoplasmosis is best predicted by prenatal examination with the combination of T gondii polymerase chain reaction and mouse inoculation of amniotic fluid. The role of cordocentesis in the diagnosis of congenital toxoplasmosis is limited.


Epidemiology and Infection | 2012

Multiple norovirus outbreaks linked to imported frozen raspberries.

E. Sarvikivi; Merja Roivainen; Leena Maunula; T. Niskanen; T. Korhonen; Maija Lappalainen; Markku Kuusi

In 2009, the number of foodborne norovirus outbreaks in Finland seemed markedly high, and many outbreaks seemed to be linked to imported frozen raspberries. We reviewed the data regarding all notified foodborne outbreaks in 2009 in Finland in order to assess the magnitude of the problem and to summarize the information on raspberry-linked outbreaks. Between March and August, 13 norovirus outbreaks affecting about 900 people could be linked to imported frozen raspberries. Two raspberry samples corresponding to two batches of raspberries were positive for norovirus. These two batches proved to have been the likely source in six of the 13 outbreaks. Analytical studies had not been conducted for six outbreaks, and virological test results were inconclusive in two. However, combining epidemiological and microbiological methods often enabled finding the source, as exemplified in investigation of a large school outbreak. To ensure prompt control measures in similar situations in the future, both aspects of outbreak investigations should be strengthened.


The Journal of Infectious Diseases | 2009

Rotavirus Surveillance in Europe, 2005–2008: Web-Enabled Reporting and Real-Time Analysis of Genotyping and Epidemiological Data

Miren Iturriza-Gomara; T. Dallman; Krisztián Bányai; Blenda Böttiger; Javier Buesa; Sabine Diedrich; Lucia Fiore; K. Johansen; Neli Korsun; A. Kroneman; Maija Lappalainen; Brigitta László; Leena Maunula; J. Matthinjnssens; Sofie Midgley; Zornitsa Mladenova; Mateja Poljšak-Prijatelj; P. Pothier; Franco Maria Ruggeri; Alicia Sánchez-Fauquier; Eckart Schreier; A. Steyer; I. Sidaraviciute; A. N. Tran; Vytautas Usonis; M. Van Ranst; A. de Rougemont; J Gray

BACKGROUND The first European rotavirus surveillance network, EuroRotaNet, comprising 16 laboratories in 15 European countries, has been established. METHODS Fecal samples from gastroenteritis cases positive for group A rotavirus antigen were collected from multiple European countries from 2005 to mid-2008 and were subjected to G and P genotyping. Epidemiological data collected included age, sex, geographical location, setting, dates of onset and sample collection, and clinical symptoms. RESULTS A total of 8879 rotavirus-positive samples were characterized: 2129 cases were from the 2005-2006 season, 4030 from the 2006-2007 season, and 2720 from the ongoing 2007-2008 season. A total of 30 different G and P type combinations of strains circulated in the region from 2005 through 2008. Of these strains, 90% had genotypes commonly associated with human infections-G1P[8], G2P[4], G3P[8], G4P[8], and G9P[8]-and 1.37% represented potential zoonotic introductions. G1P[8] remained the most prevalent genotype in Europe as a whole, but the incidence of infection with G1P[8] rotavirus strains was <50% overall, and all 3 seasons were characterized by a significant diversity of cocirculating strains. The peak incidence of rotavirus infection occurred from January through May, and 81% of case patients were aged <2.5 years. Conclusions. Data gathered through EuroRotaNet will provide valuable background information on the rotavirus strain diversity in Europe before the introduction of rotavirus vaccines, and the network will provide a robust method for surveillance during vaccine implementation.


The Journal of Pediatrics | 1999

Diagnosis of congenital toxoplasmosis in the neonatal period: A multicenter evaluation.

Anne Naessens; Pål A. Jenum; Arnold Pollak; Anne Decoster; Maija Lappalainen; Isabelle Villena; Morten Lebech; Babill Stray-Pedersen; Michael Hayde; Jean-Michel Pinon; Eskild Petersen; Walter Foulon

OBJECTIVE To evaluate different laboratory tests used to diagnose congenital toxoplasmosis in the neonatal period. STUDY DESIGN A retrospective multicenter study of 294 pregnant women who experienced seroconversion for Toxoplasma gondii and subsequently delivered live-born infants. Fetal infection was assessed via specific IgM and IgA antibodies (cord and neonatal blood) and detection of T gondii in placenta and cord blood by mouse inoculation. RESULTS Ninety-three (32%) of the 294 infants were congenitally infected. The sensitivity of IgA in cord blood and in neonatal blood was 64% and 66%; the sensitivity of IgM was 41% and 42%, respectively. Mouse inoculation of the placenta and cord blood had sensitivities of 45% and 16%. Positive results of the serologic tests in congenitally infected children correlated significantly with the gestational age at the time of maternal infection but was not significantly influenced by the administration of specific antiparasitic treatment during pregnancy. CONCLUSION Specific T gondii IgA antibody is a more sensitive test than IgM for detecting congenital toxoplasmosis in the neonatal period. The overall specificity is better for serologic tests performed on neonatal blood than for those on cord blood. Neonatal screening with IgM or IgA antibodies will not detect the majority of children with congenital toxoplasmosis when the maternal infection occurred before the 20th week of pregnancy.


Journal of Clinical Virology | 2002

CMV infection is usually associated with concurrent HHV-6 and HHV-7 antigenemia in liver transplant patients

Irmeli Lautenschlager; Maija Lappalainen; K Linnavuori; Jukka Suni; Krister Höckerstedt

Human herpesvirus 6 and 7 (HHV-6, HHV-7) have been recently reported in liver transplant patients. HHV-6 may cause fever, neurological disorders and hepatitis. The clinical significance of HHV-7 is less clear. HHV-6 and -7 are closely related to cytomegalovirus (CMV), and interactions between the viruses have also been suggested. In this study, we investigated the post transplant HHV-6 and -7 antigenemia was in relation to symptomatic CMV disease after liver transplantation. Consecutive 34 adult liver allograft recipients transplanted during 1999-2000 were included in the study. CMV infections were diagnosed by the frequent monitoring of pp65-antigenemia and by viral cultures. HHV-6 and -7 were demonstrated, by using immunoperoxidase staining and monoclonal antibodies against the virus specific antigens, in the mononuclear cells from the same blood specimens which were obtained for CMV pp65 monitoring. Altogether 322 blood specimens were analyzed. CMV disease was diagnosed in 12 (35%) patients during the first 3 months (first pp65 positive specimen mean 25 days, range 8-61 days) after transplantation. Concurrent HHV-6 antigenemia was detected in 10/12 (mean 14 days, range 6-22 days) and HHV-7 antigenemia in 9/12 patients (mean 25 days, range 10-89 days) after transplantation. HHV-6 usually appeared slightly before CMV. All CMV infections were successfully treated with ganciclovir and the CMV-antigenemia subsided. HHV-6 and -7 antigenemia also responded to the antiviral treatment, but more slowly than CMV. In conclusion, CMV infection was usually associated with HHV-6 and -7 antigenemia in liver transplant patients. The results support the suggestion that CMV, HHV-6 and -7 may have interactions. The clinical symptoms of CMV infection, may also be linked with HHV-6 or -7.


Pediatric Infectious Disease Journal | 1995

Outcome of children after maternal primary Toxoplasma infection during pregnancy with emphasis on avidity of specific IgG

Maija Lappalainen; Marjaleena Koskiniemi; Vilho Hiilesmaa; Pirkko Ämmälä; Kari Teramo; Pentti Koskela; Morten Lebech; Kari O. Raivio; Klaus Hedman

Congenital toxoplasmosis results from maternal primary infection during pregnancy. In our serologic screening study 42 of 16 733 pregnant women had findings suggestive of primary infection. Here we document the outcome of their offspring, 37 of 39 liveborn children. After 12 months postntally, serologically verified congenital toxoplamosis appeared in 4 children.


Scandinavian Journal of Infectious Diseases | 1992

Incidence of Primary Toxoplasma Infections during Pregnancy in Southern Finland: A Prospective Cohort Study

Maija Lappalainen; Pentti Koskela; Klaus Hedman; Kari Teramo; Pirkko Ämmälä; Vilho Hiilesmaa; Marjaleena Koskiniemi

Congenital toxoplasmosis may develop after maternal primary infection during pregnancy. Since toxoplasmosis in adults is usually asymptomatic, the only way to find the pregnancies at risk of acute toxoplasmosis (i.e. seronegative mothers) is to perform serological screening of all pregnant women. We studied toxoplasma-specific antibodies in 16,733 pregnant women in the first, second, and third trimesters over an 18-month period in the Helsinki area, with a population of 820,700. The participation rate in our study was 90.2% of all pregnancies in the area. The overall prevalence of toxoplasma seropositivity was 20.3%. The incidence of primary infection was 2.4/1000 pregnancies at risk. Our data on incidence suggest an annual occurrence of 131 cases of primary toxoplasma infections during pregnancy in Finland. Primary toxoplasma infection appears to be a significant risk to the fetus even in countries where the prevalence of toxoplasma seropositivity is low. The feasibility of mass screening for toxoplasma infections during pregnancy should be considered in order to reduce the morbidity and mortality due to congenital toxoplasmosis.


Food and Environmental Virology | 2009

Enteric Viruses in a Large Waterborne Outbreak of Acute Gastroenteritis in Finland

Leena Maunula; P. Klemola; A. Kauppinen; Kirsi Söderberg; T. Nguyen; T. Pitkänen; S. Kaijalainen; M. L. Simonen; Ilkka T. Miettinen; Maija Lappalainen; J. Laine; R. Vuento; M. Kuusi; M. Roivainen

In Nokia city about 450,000 l of treated sewage water was for 2 days allowed to run into the drinking water supplies of the city due to a personal error of one employee. Within the next 5 weeks about 1,000 people sought care at the municipal health centre or regional hospital because of gastroenteritis. Here we report the results of viral analyses performed by gene amplification assays from the earliest water and sewage samples as well as from close to 300 patient samples. The contaminating treated sewage was shown to harbour several enteric viruses known to cause acute gastroenteritis. Likewise, the drinking water sample was positive for noro-, astro-, rota-, entero- and adenoviruses. Noroviruses were also found in 29.8% of stool samples from affected patients, while astro-, adeno-, rota- and enteroviruses were detected in 19.7, 18.2, 7.5 and 3.7% of the specimens, respectively.

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Klaus Hedman

Helsinki University Central Hospital

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Laura Mannonen

Helsinki University Central Hospital

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Leena Maunula

Helsinki University Central Hospital

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Markku Kuusi

National Institute for Health and Welfare

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Antti Vaheri

Helsinki University Central Hospital

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