Search

Introduction: On May 3, 2009, a first case of influenza A/H1N1 infection occurred in the federal state of Saxony-Anhalt, Germany. In order to stop the possible spread of the virus and to study the epidemiological and clinical characteristics of the infection, an investigation was launched by the local health authorities and the RKI. Methods: Standardised questionnaires were used to assess demographic and clinical data. Specimens were collected from case patients and close contacts and were analysed for influenza A/H1N1 using real-time PCR. Results: The index patient showed fever and coughing 3.5 days after returning from a holiday in Mexico. The local health authorities were informed on May 3, and measures were rapidly implemented. These measures included a trace-back of possible contact persons, isolation of the case and close contacts, prophylactic treatment with Oseltamivir. Virological investigations showed that the case shedded viral genome up until the last day of antiviral therapy. Viral genome was also detected in the spouse and the son of the patient. Both showed no symptoms under a prophylactic treatment with antiviral medication. No viral genome was detected in three other family members, and in six other contact persons outside of the family. Discussion: The spread of the virus was contained due to the fast response of the local health authorities. Two secondary cases occurred in the family. These cases remained asymptomatic, possibly due to antiviral prophylaxis. Epidemiological and virological results suggest that the influenza A/H1N1 virus has a longer incubation period and that viral shedding may probably be prolonged when compared with seasonal influenza.

From August 2004 to January 2005 a cluster of 7 cases of serogroup B meningococcal disease occurred in the state of Saxony-Anhalt in the town of Sangerhausen and the surrounding area. This led to an investigation of meningococcal carriage in 816 high school students (grades 9 to 13). The students were also asked to fill out a questionnaire regarding possible risk factors for carriage. The goal of the study was the evaluation of a possibly persistently increased risk for further cases in the region. Results of the study were to be used for a comprehensive and targeted education of the public. The percentage of students found harbouring N. meningitidis in the nasopharynx in Sangerhausen (9.0 %) was not elevated compared to that found in the two control regions of Kelbra, County of Sangerhausen (8.2 %) and Jessen, County of Wittenberg (9.9 %). The serogroup B fine type responsible for the cluster (P1.7-2,16:F3-3:PorB3-24) was found only in one student each in Sangerhausen and Kelbra. Thus, there was no evidence of an increased risk for further cases at the time of the study at the end of January, 2005. This may have been due to intensive contact tracing and provision of chemoprophylaxis in Sangerhausen. Visiting a disco or bar and smoking were identified as risk factors for meningococcal carriage. However, these factors were associated with carriage only in boys but not in girls. This may be explained by sex-specific differences in physical interaction with others. Efforts to prevent further cases during clusters of meningococcal disease should consider sex-specific risk behaviour.