Impact of Changes in Infection Control Measures on the Dynamics of COVID-19 Infections in Schools and Pre-schools.

Introduction: With the increased emergence of SARS-CoV-2 variants, the impact on schools and preschools remains a matter of debate. To ensure that schools and preschools are kept open safely, the identification of factors influencing the extent of outbreaks is of importance. Aim: To monitor dynamics of COVID-19 infections in schools and preschools and identify factors influencing the extent of outbreaks. Methods: In this prospective observational study we analyzed routine surveillance data of Mecklenburg-Western Pomerania, Germany, from calendar week (CW) 32, 2020 to CW19, 2021 regarding SARS-CoV-2 infection events in schools and preschools considering changes in infection control measures over time. A multivariate linear regression model was fitted to evaluate factors influencing the number of students, teachers and staff tested positive following index cases in schools and preschools. Due to an existing multicollinearity in the common multivariate regression model between the variables "face mask obligation for children" and "face mask obligation for adults", two further separate regression models were set up (Multivariate Model Adults and Multivariate Model Children). Results: We observed a significant increase in secondary cases in preschools in the first quarter of 2021 (CW8 to CW15, 2021), and simultaneously a decrease in secondary cases in schools. In multivariate regression analysis, the strongest predictor of the extent of the outbreaks was the teacher/ caregiver mask obligation (B = -1.9; 95% CI: -2.9 to -1.0; p < 0.001). Furthermore, adult index cases (adult only or child+adult combinations) increased the likelihood of secondary cases (B = 1.3; 95% CI: 0.9 to 1.8; p < 0.001). The face mask obligation for children also showed a significant reduction in the number of secondary cases (B = -0.6; 95% CI: -0.9 to -0.2; p = 0.004. Conclusion: The present study indicates that outbreak events at schools and preschools are effectively contained by an obligation for adults and children to wear face masks.

[Screening of Mothers in a COVID-19 Low-Prevalence Region: Determination of SARS-CoV-2 Antibodies in 401 Mothers from Rostock by ELISA and Confirmation by Immunofluorescence]. / Mütter-Screening in einem COVID-19-Niedrig-Pandemiegebiet: Bestimmung SARS-CoV-2-spezifischer Antikörper bei 401 Rostocker Müttern mittels ELISA und Immunfluoreszenz-Bestätigungstest.

BACKGROUND: In children, the infection with SARS-CoV-2, the cause of COVID-19, tends to be clinically inapparent more often or less severe than in adults. The spread of this infection from children poses a danger to vulnerable adults. Therefore, child care institutions and schools currently are widely closed. METHODS: Since the status of infection tends to be congruent in mothers and their children, we tested 401 mothers of children between 1 and 10 years in the city of Rostock (State of Mecklenburg-Westpomerania, northeast of Germany), for the presence of RNA of SARS-CoV-2 in throat swabs, and of antibodies against SARS-CoV-2 in serum. RESULTS: In none of the mothers tested, RNA of this virus was detected in the throat swab. In the ELISA test, IgG antibodies were positive in one serum sample, IgA antibodies were positive in 11, and borderline in 3 serum samples. All 401 sera were negative in the indirect immunofluorescence test (IIFT) with FITC-labeled IgG, IgA, und IgM antibodies. CONCLUSION: At the time of this study, neither SARS-CoV-2 RNA, nor specific antibodies against SARS-CoV-2 were detectable in the mothers tested in Rostock.

Extensively drug-resistant Klebsiella pneumoniae ST307 outbreak, north-eastern Germany, June to October 2019.

From June to October 2019, 17 patients (six infected, 11 colonised) with an extensively drug-resistant (XDR) Klebsiella pneumoniae strain were notified from four Western Pomerania medical facilities. The XDR K. pneumoniae produced carbapenemases NDM-1 and OXA-48, and was only susceptible to chloramphenicol, tigecycline and cefiderocol. Synergistic activity was observed for the combination of aztreonam plus ceftazidime-avibactam. Genomic analyses showed all isolates belonged to K. pneumoniae sequence type 307. Control measures and further investigations are ongoing.

Post-exposure prophylaxis for measles with immunoglobulins revised recommendations of the standing committee on vaccination in Germany.

Passive immunisation with immunoglobulins as post-exposure prophylaxis after contact with measles is recommended by the German Standing Committee on Vaccination (STIKO) particularly for unprotected individuals at high risk of complications for whom active immunization is contraindicated, such as infants <6 months of age, immunocompromised patients and pregnant women. The efficacy of passive immunisation in preventing measles depends on how soon after exposure it is administered, the concentration of measles antibodies in the immunoglobulin products and dosage. Since the global introduction of standard active immunisation against measles and the concomitant reduction in virus circulation, the levels of measles virus (MV)-specific IgG antibodies in the population have dropped. Thus, the concentration of MV-specific antibodies in immunoglobulin products derived from human plasma donors has declined as the proportion of vaccinated donors has increased. The MV-neutralizing capacity of immunoglobulin products is not routinely tested in Germany. No official data exist on the concentrations of MV-specific IgG antibodies in individual batches of immunoglobulins available in Germany and the required minimum level for MV-specific IgG is not stipulated. The STIKO re-evaluated available data and measurements of MV-neutralizing capacities of available immunoglobulin (IgG) products in Germany at the National Reference Centre Measles, Mumps, Rubella at the Robert Koch Institute. Based on the findings, STIKO modified its previous recommendations on the post-exposure use of immunoglobulins (2001), especially with respect to risk groups, application and dosage. STIKO now recommends a single intravenous administration of immunoglobulins (400 mg/kg body weight) as soon as possible, preferably within six days, after exposure to measles, specifically for infants aged <6 months, susceptible pregnant women and immunocompromised patients.

Incidence of notified Lyme borreliosis in Germany, 2013-2017.

Lyme borreliosis (LB) is the most commonly reported tick-borne disease in Germany. In 9/16 states, notification of erythema migrans (EM), acute neuroborreliosis (NB) and Lyme arthritis (LA) is mandatory. We describe incidence measures, time trends, geographical distribution and frequencies of manifestations to better understand LB epidemiology and target prevention measures. We used cases notified in the 9 states and confirmed by local health offices, 2013-2017, to calculate incidences by time, place and person. Altogether, we observed 56,446 cases. Disease onset peaked yearly in July. Incidence ranged from 26/100,000 (2015) to 41/100,000 (2013) with mean annual incidences 2013-2017 on district level between 0.5/100,000 and 138/100,000. Median age was 54 years with peaks in boys (5-9 years, mean incidence 36/100,000) and women (50-69 years, mean incidence 57/100,000). 95% experienced EM only, 2.7% NB and 2.1% LA. 54% were female, but more men had NB (56%) and LA (53%, p < 0.001). Hospitalisation was recorded for 10% of LA and 71% of NB cases. LB remains an important public health concern in Germany with marked regional variation. To facilitate early diagnosis and treatment, health authorities should raise awareness among physicians and promote prevention strategies among the general population: tick-bite-protection, prompt tick removal and medical consultation.

Long-lasting cough in an adult German population: incidence, symptoms, and related pathogens.

Studies of the incidence of pertussis in adults have shown that it accounts for only 5-15% cases of prolonged coughing. We assessed the burden of suffering related to prolonged coughing and tried to identify further causative agents. Based on a sentinel study with 35 general practitioners in two German cities (Krefeld, Rostock), with 3,946 patients fulfilling the inclusion criteria, we estimated the incidence of prolonged coughing in adults. In 975 of these outpatients, PCR and/or serology for adenovirus, Bordetella pertussis and B. parapertussis, human metapneumovirus, influenza virus A and rhinovirus, parainfluenza virus, Mycoplasma pneumonia, and respiratory syncytial virus (RSV) were performed. Treatment data were extracted for a subgroup of 138 patients. Descriptive statistics, including Kaplan-Maier curves were generated. Yearly incidence ranged between 1.4 and 2.1% per population in the two cities. Adult patients sought medical attention only after a median of 3 weeks of coughing. Irrespective of smoking and unrelated to the identified pathogens, the median duration of coughing was 6 weeks, with an interquartile range of 4-11 weeks. In 48.3% of patients, possible pathogens were identified, among which adenovirus (15.1%), RSV (7.5%), B. pertussis (5.6%), and influenza viruses (4.0%) were most often found. Symptoms were not indicative of a specific agent and a total of 64% of patients received antibiotics. Prolonged adult coughing requiring medical attention prompts substantial healthcare use. Apart from B. pertussis, a broad range of pathogens was associated with the symptoms. However, patients sought medical attention too late to guide efficacious therapeutic interventions using the diagnostic tests.

Tick-borne encephalitis virus habitats in North East Germany: reemergence of TBEV in ticks after 15 years of inactivity.

The incidence of tick-borne encephalitis has risen in Europe since 1990 and the tick-borne encephalitis virus (TBEV) has been documented to be spreading into regions where it was not previously endemic. In Mecklenburg-West Pomerania, a federal state in Northern Germany, TBEV was not detectable in over 16,000 collected ticks between 1992 and 2004. Until 2004, the last human case of TBE in the region was reported in 1985. Following the occurrence of three autochthonous human cases of TBE after 2004, however, we collected ticks from the areas in which the infections were contracted. To increase the chance of detecting TBEV-RNA, some of the ticks were fed on mice. Using nested RT-PCR, we were able to confirm the presence of TBEV in ticks for the first time after 15 years. A phylogenetic analysis revealed a close relationship between the sequences we obtained and a TBEV sequence from Mecklenburg-East Pomerania published in 1992 and pointed to the reemergence of a natural focus of TBEV after years of low activity. Our results imply that natural foci of TBEV may either persist at low levels of activity for years or reemerge through the agency of migrating birds.

Rotavirus vaccine effectiveness and case-control study on risk factors for breakthrough infections in Germany, 2010-2011.

BACKGROUND: In the German federal state Mecklenburg-Western Pomerania, routine rotavirus (RV) vaccination in infants has been recommended since 2009. The effectiveness of RV vaccination was investigated after an unexpectedly high number of RV infections in fully vaccinated children occurred. METHODS: Intensified RV surveillance was performed in Mecklenburg-Western Pomerania between 2010 and 2011. The screening method was applied to assess vaccine effectiveness (VE) in children up to 24 months after vaccination. To identify risk factors for breakthrough infections, a case-control study and genotyping were conducted in vaccinated and unvaccinated RV-infected children. RESULTS: VE for the prevention of RV infection requiring medical attention or hospitalization was 68% (95% confidence interval [CI]: 61-71) and 80% (95% CI: 77-83), respectively. VE for preventing hospitalization but not medical attention remained stable over 2 years. Vaccinated were less often hospitalized (23%) than unvaccinated RV-infected children (61%; P < 0.001). Breastfeeding (odds ratio, 3.99; 95% CI: 1.92-8.27) and attending daycare (odds ratio, 3.42; 95% CI: 1.64-7.12) were independently associated with breakthrough infections. Genotype G1P[8] was detected more frequently in RotaTeq-vaccinated (44% versus 11%; P < 0.03) and G2P[4] in Rotarix-vaccinated children (42% versus 6%; P < 0.02). CONCLUSIONS: RV vaccination protects young children effectively from RV disease and can reduce disease severity. Breastfeeding might impair VE, but further research is needed to identify the critical time window for this interference and to develop appropriate recommendations.

Effectiveness of the AS03-adjuvanted vaccine against pandemic influenza virus A/(H1N1) 2009--a comparison of two methods; Germany, 2009/10.

During the autumn wave of the pandemic influenza virus A/(H1N1) 2009 (pIV) the German population was offered an AS03-adjuvanted vaccine. The authors compared results of two methods calculating the effectiveness of the vaccine (VE). The test-negative case-control method used data from virologic surveillance including influenza-positive and negative patients. An innovative case-series methodology explored data from all nationally reported laboratory-confirmed influenza cases. The proportion of reported cases occurring in vaccinees during an assumed unprotected phase after vaccination was compared with that occurring in vaccinees during their assumed protected phase. The test-negative case-control method included 1,749 pIV cases and 2,087 influenza test-negative individuals of whom 6 (0.3%) and 36 (1.7%), respectively, were vaccinated. The case series method included data from 73,280 cases. VE in the two methods was 79% (95% confidence interval (CI) = 35-93%; P = 0.007) and 87% (95% CI = 78-92%; P<0.001) for individuals less than 14 years of age and 70% (95% CI = -45%-94%, P = 0.13) and 74% (95% CI = 64-82%; P<0.001) for individuals above the age of 14. Both methods yielded similar VE in both age groups; and VE for the younger age group seemed to be higher.

Human cowpox virus infection acquired from a circus elephant in Germany.

A 40-year-old Asian circus elephant developed mouth and trunk ulcers. Three weeks later, her 19-year-old animal warden noticed a vesicle on his forearm, evolving into a scab. Identical cowpox strains were isolated from lesions of the elephant and the warden. Cowpox virus could no longer be isolated after the scab disappeared, but PCR still revealed orthopox DNA. Healing was complete seven weeks later, leaving a 1 cm scar.

Impact of community-acquired paediatric rotavirus gastroenteritis on family life: data from the REVEAL study.

BACKGROUND: Rotavirus is the leading cause of acute gastroenteritis (AGE) and the most frequent cause of severe diarrhoea in children aged less than 5 years. Although the epidemiology of rotavirus gastroenteritis (RVGE) is well documented, there are few data on the impact of RVGE on the families of affected children. METHODS: Data associated with the burden of RVGE, including number of working days lost, levels of parental stress, the need for alternative childcare arrangements and additional nappies used, were extracted from questionnaires completed by parents of children participating in a prospective, multicentre, observational study (Rotavirus gastroenteritis Epidemiology and Viral types in Europe Accounting for Losses in public health and society, REVEAL), conducted during 2004-2005 in selected areas of Belgium, France, Germany, Italy, Spain, Sweden, and the United Kingdom to estimate the incidence of RVGE in children aged less than 5 years seeking medical care as a result of AGE. RESULTS: 1102 children with RVGE were included in the present analysis. The proportion of RVGE cases that required at least one parent or other person to be absent from work was 39%-91% in the hospital setting, 44%-64% in the emergency department, and 20%-64% in primary care. Self-reported levels of parental stress were generally high (mean stress levels, > or = 5 on a 10-point visual analogue scale). Additional childcare arrangements were required in up to 21% of RVGE episodes. The mean number of nappies used per day during RVGE episodes was approximately double that used when the child was not ill. CONCLUSIONS: Paediatric RVGE cases cause disruption to families and parental stress. The burden of RVGE on children and their families could be substantially reduced by routine rotavirus vaccination of infants.

Protective measures and H5N1-seroprevalence among personnel tasked with bird collection during an outbreak of avian influenza A/H5N1 in wild birds, Ruegen, Germany, 2006.

BACKGROUND: In Germany, the first outbreak of highly pathogenic avian influenza A/H5N1 occurred among wild birds on the island of Ruegen between February and April 2006. The aim of this study was to investigate the use of recommended protective measures and to measure H5N1-seroprevalence among personnel tasked with bird collection. METHODS: Inclusion criteria of our study were participation in collecting wild birds on Ruegen between February and March 2006. Study participants were asked to complete a questionnaire, and to provide blood samples. For evaluation of the use of protective measures, we developed a personal protective equipment (PPE)-score ranging between 0 and 9, where 9 corresponds to a consistent and complete use of PPE. Sera were tested by plaque neutralization (PN) and microneutralization (MN) assays. Reactive sera were reanalyzed in the World Health Organization-Collaborating Centre (WHO-CC) using MN assay. RESULTS: Of the eligible personnel, consisting of firemen, government workers and veterinarians, 61% (97/154) participated in the study. Of those, 13% reported having always worn all PPE-devices during bird collection (PPE-score: 9). Adherence differed between firemen (mean PPE-score: 6.6) and government workers (mean PPE-score: 4.5; p = 0.006). The proportion of personnel always adherent to wearing PPE was lowest for masks (19%). Of the participants, 18% had received seasonal influenza vaccination prior to the outbreak. There were no reports of influenza-like illness. Five sera initially H5-reactive by PN assay were negative by WHO-CC confirmatory testing. CONCLUSION: Gaps and variability in adherence demonstrate the risk of exposure to avian influenza under conditions of wild bird collection, and justify serological testing and regular training of task personnel.

Pertussis outbreak in primary and secondary schools in Ludwigslust, Germany demonstrating the role of waning immunity.

A pertussis outbreak primarily affecting school-age children in Ludwigslust, Germany, was investigated in 2006 to estimate attack rates and relative risk of pertussis according to time since last vaccination, after a complete primary course. Results suggested waning immunity beginning approximately 5 years after the last dose of pertussis vaccination. Most cases could have been prevented by earlier booster vaccination.

The epidemiology of pertussis in Germany: past and present.

BACKGROUND: Current and past pertussis epidemiology in the two parts of Germany is compared in the context of different histories of vaccination recommendations and coverage to better understand patterns of disease transmission. METHODS: Available regional pertussis surveillance and vaccination coverage data, supplemented by a literature search for published surveys as well as official national hospital and mortality statistics, were analyzed in the context of respective vaccination recommendations from 1964 onwards. RESULTS: Routine childhood pertussis vaccination was recommended in the German Democratic Republic (GDR) from 1964 and in former West German states (FWG) from 1969, but withdrawn from 1974-1991 in FWG. Pertussis incidence declined to <1 case/100,000 inhabitants in GDR prior to reunification in 1991, while in FWG, where pertussis was not notifiable after 1961, incidence was estimated at 160-180 cases/100,000 inhabitants in the 1970s-1980s. Despite recommendations for universal childhood immunization in 1991, vaccination coverage decreased in former East German States (FEG) and increased only slowly in FWG. After introduction of acellular pertussis vaccines in 1995, vaccination coverage increased markedly among younger children, but remains low in adolescents, especially in FWG, despite introduction of a booster vaccination for 9-17 year olds in 2000. Reported pertussis incidence increased in FEG to 39.3 cases/100,000 inhabitants in 2007, with the proportion of adults increasing from 20% in 1995 to 68% in 2007. From 2004-2007, incidence was highest among 5-14 year-old children, with a high proportion fully vaccinated according to official recommendations, which did not include a preschool booster until 2006. Hospital discharge statistics revealed a ~2-fold higher pertussis morbidity among infants in FWG than FEG. CONCLUSION: The shift in pertussis morbidity to older age groups observed in FEG is similar to reports from other countries with longstanding vaccination programs and suggests that additional booster vaccination may be necessary beyond adolescence. The high proportion of fully vaccinated cases in older children in FEG suggests waning immunity 5-10 years after primary immunisation in infancy. The higher incidence of pertussis hospitalisations in infants suggests a stronger force of infection in FWG than FEG. Nationwide pertussis reporting is required for better evaluation of transmission patterns and vaccination policy in both parts of Germany.

Long-term immunogenicity of a single dose of acellular pertussis vaccine in paediatric health-care workers.

OBJECTIVE: Monitor the long-term immunogenicity of a single dose of acellular pertussis vaccine in health-care workers. DESIGN: German health-care workers and child-care workers received a single dose of a monovalent acellular pertussis vaccine (PAC-Mérieux) in an open-label study. Blood samples were taken before (n=261), 4 weeks after (n=246), 1 year (n=187), 2 years (n=53), 3 years (n=134) and 4 years (n=37) after vaccination. IgG- and IgA-anti-pertussis-toxin (PT), IgG- and IgA-anti-filamentous hemagglutinin (FHA), and IgG-anti-pertactin (PRN) were measured by ELISA. RESULTS: Of all subjects, 97.1%, 99.2% and 97.2% had an antibody response to PT, FHA and PRN, respectively. Four weeks after vaccination the median titres of IgG antibodies to PT, FHA and PRN were 314, 785 and 84 EU/l, respectively, and all vaccinees had an immune response to at least one pertussis antigen. IgA-anti-PT and IgA-anti-FHA responses were found in 63.4% and 96.3% of subjects with a median titre of 30 and 196 EU/ml, respectively. The titre of IgG-anti-PT decreased slowly with a median concentration of 76, 71, 71 and 63 EU/ml after 1, 2, 3 and 4 years, respectively. Secondary titre increases were observed in 0.5%, 3.3%, 5.6% and 12.5% of the vaccinees 1, 2, 3, and 4 years after vaccination. CONCLUSION: In German health paediatric care workers long-lasting immune responses with high antibody levels could be induced by a single dose of acellular pertussis vaccine. A renewed contact with B. pertussis antigens resulted in a measurable immune response to PT between 0.5% (1 year p.v.) and 12.5% (4 years p.v.).

Pertussis: not only a disease of childhood.

INTRODUCTION: Pertussis is not just a childhood disease, but a respiratory infection that causes persistent cough in all age groups, from newborns to the elderly. METHODS: The authors performed a selective literature search and reviewed national and international recommendations for treatment and vaccination. RESULTS: Pertussis is found principally in young unvaccinated infants, but school-age children, adolescents, and adults are also affected. Up to 1% of infants contract pertussis, and their respiratory symptoms are often accompanied by apnea. School-age children occasionally display the coughing spasms typical of the disease. Annually, 0.2% to 0.5% of all adolescents and adults are infected and suffer from prolonged, frequently non-paroxysmal coughing. Severe and fatal cases of pertussis occur mainly in newborns and infants, and 25% of affected adults experience complications. Bordetella DNA may be detected by polymerase chain reaction (PCR) for four weeks after symptom onset; except in infants, the sensitivity of this diagnostic technique is low. Although the diagnosis can be confirmed by serological tests, the methods are not well standardized. Treatment with a macrolide prevents the spread of infection, but generally does not alleviate the symptoms. Combination vaccines are the most effective means of prophylaxis. DISCUSSION: Pertussis is usually not included in the differential diagnosis of persistent respiratory symptoms. The considerable burden of disease could be reduced in adults and young infants by vaccinating adults with acellular combination vaccines.

A multistate outbreak of Shiga toxin-producing Escherichia coli O26:H11 infections in Germany, detected by molecular subtyping surveillance.

In the spring of 2000, a cluster of indistinguishable Shiga toxin-producing Escherichia coli (STEC) O26:H11 was identified in Germany by molecular subtyping surveillance. An investigation was prompted to identify a common source of exposure. A case subject was defined as a person having a polymerase chain reaction-confirmed STEC O26 infection between March and April 2000, irrespective of clinical signs, and whose isolate was indistinguishable from the index strain by use of pulsed-field gel electrophoresis. Eleven case subjects were found in 5 institutions that were supplied by 4 kitchens located in 3 states. The median age was 2 years (range, 2-31 years). No bloody diarrhea was reported, and 5 persons remained asymptomatic. Comparison of invoices revealed a certain type of beef ("Seemerrolle") as possible source of infection. This is, to our knowledge, the first multistate outbreak associated with a non-O157 STEC detected by laboratory-based surveillance. Molecular subtyping was pivotal, as disease occurrence was sporadic or family-related.