Recurrent tuberculosis (TB) is caused by an endogenous re-activation of the same strain of Mycobacterium tuberculosis (relapse) or exogenous infection with a new strain (re-infection). Recurrence of TB in Finland was analysed in a population-based, 19-year study, and genotyping was used to define relapse and re-infection. The M. tuberculosis isolates from patients with suspected relapse were further analysed by whole genome sequencing (WGS) to determine the number and type of mutations occurring in the bacterial genome between the first and second disease episodes. In addition, publicly available tools (PhyResSE and SpolPred) were used to predict drug resistance and spoligotype profile from the WGS data. Of the 8299 notified TB cases, 48 (0.6%) patients had episodes classified as recurrent. Forty-two patients had more than one culture-confirmed TB episode, and isolates from two episodes in 21 patients were available for genotyping. In 18 patients, the M. tuberculosis isolates obtained from the first and second TB episodes had identical spoligotypes. The WGS analysis of the 36 M. tuberculosis isolates from the 18 suspected relapse patients (average time between isolates 2.8 years) revealed 0 to 38 single nucleotide polymorphisms (median 1, mean 3.78) between the first and second isolate. There seemed to be no direct relation between the number of years between the two isolates, or treatment outcome, and the number of single nucleotide polymorphisms. The results suggest that the mutation rate may depend on multiple host-, strain- and treatment-related factors.
SUMMARY Increasing immigration from high tuberculosis (TB) incidence countries is a challenge for surveillance and control in Finland. Here, we describe the epidemiology of TB in immigrants by using national surveillance data. During 1995–2013, 7030 (84·7%) native and 1199 (14·4%) immigrant cases were identified. The proportion of immigrant cases increased from 5·8% in 1995 to 32·1% in 2013, consistent with increasing immigrant population (2·1–5·6%) and decreasing incidence of TB in the native population (from 12·1 to 3·5/100 000). TB cases in immigrants were significantly younger, more often female, and had extrapulmonary TB more often than native cases ( P < 0·01 for all comparisons); multidrug resistance was also more common in immigrants than natives ( P < 0·01). Immigrant cases were born in 82 different countries; most commonly in Somalia and the former Soviet Union/Russia. During 2008–2013, 433 Mycobacterium tuberculosis isolates from immigrants were submitted for spoligotyping; 10 different clades were identified. Clades were similar to those found in the case's country of birth. Screening immigrants from high-incidence countries and raising awareness of common characteristics and symptoms of TB is important to ensure early diagnosis and to prevent transmission.
The Mycobacterium tuberculosis genotypes obtained from elderly Finns were assessed and compared with those obtained from younger Finns to comprehend the epidemiology of tuberculosis (TB) in Finland. From 2008 to 2011, a total of 1021 M. tuberculosis isolates were characterized by spoligotyping and 15-locus mycobacterial interspersed repetitive units-variable number tandem repeat typing. In total, 733 Finnish-born cases were included in the study, of which 466 (64%) were born before 1945 (older Finns). Of these, 63 (14%) shared an M. tuberculosis genotype with foreign-born or younger Finnish cases (born after 1945), and 59 (13%) shared a genotype with older Finnish cases. Eighty-five per cent had a unique genotypic profile while 70% belonged to T or Haarlem families, suggesting that ongoing transmission is infrequent among young and elderly Finns. Simultaneous reactivation of TB among older Finns was the most likely cause for clustering. As most isolates belonged to Haarlem or T, Finland was most likely affected by a similar TB epidemic at the beginning of the twentieth century as that seen in Sweden and Norway. Younger Finns were significantly more likely to be clustered (56% versus 27%, p<0.001), have pulmonary TB (87% versus 71%, p<0.001) and to be sputum smear positive (57% versus 48%, p<0.05) indicating that the risk of TB transmission from younger Finns is likely to be larger than from older Finns. The M. tuberculosis isolates from elderly Finns were associated with dominant lineages of the early twentieth century and differed from the heterogeneous lineages found among younger TB patients. Additionally, younger TB patients were more likely to transmit TB than elderly Finns.
In Finland all clinically diagnosed hepatitis C virus infections have been reported to National Infectious Disease Register (NIDR) starting at 1995. Between the years 1995 and 2011 approximately 24,000 HCV infections have been reported. Because of the changed policies in HCV reporting, same individuals may have been reported to NIDR several times at early stages of NIDR existence. Therefore we have characterized the epidemiology of HCV infection in individuals who were reported to NIDR with their social security number. This group contains nearly 20,000 individuals of whom almost 2000 were of foreign origin. Two-thirds of HCV cases are males. At the time of HCV diagnosis most people were young adults, between 20 and 30 years of age. There has been some fluctuation in the age group-specific trends. The incidence has been the highest among 20–24 years females and in 25–29 males during the last years. Regionally the highest HCV incidence (33/100,000) was found in the hospital district of Helsinki metropolitan area and lowest (6–10/100,000) in the hospital districts of Eastern Savo, Åland, Kainuu, Central and Southern Ostrobothnia. Almost half of the cases were found within Helsinki university hospital district. 17% of HCV cases have died by the end of the year 2011. The most common causes of death were either related to liver diseases: viral hepatitis, cirrhosis and cancer, caused by alcohol abuse and intoxications or by accidents or suicides. HCV-infected individuals appear to die younger than the average Finnish people. The most common way to contract HCV infection in Finland is intravenous drug use. HCV-antibody prevalence among intravenous drug users in Finland was over 60% in 2009 and over 40% among studied inmates in 2006. HCV prevalence among pregnant women has increased from 0.19% to 0.64% during 1985–2010. However, among blood donors HCV prevalence has been clearly decreasing being 0.006% in 2011. According to HCV-genotyping studies the main HCV-genotypes circulating in Finland belong to 3a, 1a, 1b and 2b subtypes.
Bloodstream infections (BSI) are a major cause of mortality, morbidity and medical cost, but few population-based studies have concomitantly evaluated BSI incidence and mortality. Data on BSI episodes reported to national, population-based surveillance by all clinical microbiology laboratories in Finland during 2004-07 were linked to vital statistics. Age-, sex and microbe-specific incidence and mortality rates were calculated. During 2004-07, 33 473 BSI episodes were identified; BSI incidence increased from 147 to 168 per 100 000 population (average annual increase, 4.4%; p <0.001). Rates were highest among persons ≥65 years and <1 year, and higher among male patients than female patients (166 versus 152 per 100 000). The most common aetiologies were Escherichia coli (27%) and Staphylococcus aureus (13%). Among male patients, 52% of BSI were caused by gram-positive bacteria compared with 42% among female patients (p <0.001). The overall 30-day case-fatality was 13%. Of the deaths, 32% occurred within 2 days, 70% were among people aged 65 years or more and 33% were caused by E. coli or S. aureus infections. The BSI mortality rate increased from 19 to 22 per 100 000 (average annual increase: 4.0%, p 0.01). Among people aged 25 years or more, the mortality rate was 1.4-fold higher in men than women (34 versus 25 per 100 000 population). Overall excess annual mortality from BSI in the population was 18 per 100 000. The substantial BSI burden among the elderly and among adult men highlights the need for developing and implementing effective interventions, particularly for BSI caused by E. coli and S. aureus. One-third of BSI deaths occurred early, emphasizing the importance of early identification and treatment.
The first infection caused by pandemic influenza A(H1N1)2009 virus was confirmed in Finland on 10 May 2009. The spread of the disease and its impact were monitored using several surveillance systems, such as the national infectious disease register, notifications of clusters of influenza, influenza-like or influenza-related illnesses, as well as virological, hospital, case-based and mortality surveillance. The epidemic started in early October in the north and then spread to the south about two weeks later. Based on the data from laboratory-confirmed cases, the morbidity was highest in children. The daily number of patients hospitalised with influenza A(H1N1)2009 reached a maximum of over 400 in late November. Of the 1,580 hospitalised patients (median age 32 years), 672 (43%) had at least one chronic underlying illness, 35 (2%) were pregnant, 132 (8%) were treated in intensive care units and 74 (5%) required mechanical ventilation. The median age of patients admitted to intensive care units was 48 years and 78 (59%) of them had at least one chronic underlying disease, none were pregnant. Altogether 44 deaths related to influenza A(H1N1)2009 were recorded (median age 56 years): 40 belonged to high-risk groups on the basis of underlying chronic diseases. Combining data from different surveillance systems gave timely information about the spread of the pandemic and contributed to identifying risk groups.
In October 2011 in Finland, two persons fell ill with symptoms compatible with botulism after having eaten conserved olives stuffed with almonds. One of these two died. Clostridium botulinum type B and its neurotoxin were detected in the implicated olives by PCR and mouse bioassay, respectively. The olives were traced back to an Italian manufacturer and withdrawn from the market. The public and other European countries were informed through media and Europe-wide notifications.
An inappropriate cross-connection between sewage- and drinking-water pipelines contaminated tap water in a Finnish town, resulting in an extensive waterborne gastroenteritis outbreak in this developed country. According to a database and a line-list, altogether 1222 subjects sought medical care as a result of this exposure. Seven pathogens were found in patient samples of those who sought treatment. To establish the true disease burden from this exposure, we undertook a population-based questionnaire investigation with a control population, infrequently used to study waterborne outbreaks. The study covered three areas, contaminated and uncontaminated parts of the town and a control town. An estimated 8453 residents fell ill during the outbreak, the excess number of illnesses being 6501. Attack rates were 53% [95% confidence interval (CI) 49.5-56.4] in the contaminated area, 15.6% (95% CI 13.1-18.5) in the uncontaminated area and 6.5% (95% CI 4.8-8.8) in the control population. Using a control population allowed us to differentiate baseline morbidity from the observed morbidity caused by the water contamination, thus enabling a more accurate estimate of the disease burden of this outbreak.
The objectives of the first national prevalence survey on healthcare-associated infections (HAIs) in Finland were to assess the extent of HAI, distribution of HAI types, causative organisms, prevalence of predisposing factors and use of antimicrobial agents. The voluntary survey was performed during February–March 2005 in 30 hospitals, including tertiary and secondary care hospitals and 10 (25%) other acute care hospitals in the country. The overall prevalence of HAI was 8.5% (703/8234). Surgical site infection was the most common HAI (29%), followed by urinary tract infection (19%) and primary bloodstream infection or clinical sepsis (17%). HAI prevalence was higher in males, among intensive care and surgical patients, and increased with age and severity of underlying illness. The most common causative organisms, identified in 56% (398/703) of patients with HAIs, were Escherichia coli (13%), Staphylococcus aureus (10%) and Enterococcus faecalis (9%). HAIs caused by multi-resistant microbes were rare (N=6). A total of 122 patients were treated in contact isolation due to the carriage of multi-resistant microbes. At the time of the survey, 19% of patients had a urinary catheter, 6% central venous line and 1% were ventilated. Antimicrobial treatment was given to 39% of patients. These results can be used for prioritising infection control measures and planning more detailed incidence surveillance of HAI. The survey was a useful tool to increase the awareness of HAI in participating hospitals and to train infection control staff in diagnosing HAIs.
A national, population-based laboratory surveillance of bloodstream infections (BSI) in Finland was performed. Blood-culturing rates were determined from data from clinical microbiology laboratories and trends in rates were evaluated using Poisson regression. During 1995-2002, 51,510 cases of BSI were notified; the annual incidence increased from 104 to 145 cases/100,000 (40%). Rates increased in all age groups but persons aged >or= 75 years accounted for 28% of cases and showed the largest rate increase. Escherichia coli, coagulase-negative staphylococci, Staphylococcus aureus and Streptococcus pneumoniae accounted for 58% of isolates and their relative proportions were unchanged over time. The annual blood-culturing rate increased by one-third during the study period but the number of BSI detected per blood cultures remained unchanged. Regional BSI incidence was significantly associated with blood-culturing rates. We conclude that the increase in BSI rates may have been due to more frequent blood culturing but was not associated with changes in the reporting system or aetiology of BSI.
Objective To determine predictors of death among children 2 - 59 months old admitted to hospital with severe pneumonia. methods Prospective observational study from April 1994 to May 2000 to investigate serious infections in children less than 5 years old admitted to a tertiary care government hospital in a rural province in central Philippines. The quality of clinical and laboratory work was monitored. The WHO classification for severe pneumonia was used for patient enrolment.Results There were 1249 children with severe pneumonia and no CNS infection. Thirty children died. Using univariate analysis, the following factors were significantly associated with death: age 2 - 5 months, dense infiltrates on chest radiography and presence of definite bacterial pathogens in the blood. Stepwise logistic regression analysis revealed the following independent predictors of death: age 2 - 5 months, weight for age z- score less than) 2 SD, dense infiltrates on chest radiography and definite pathogens isolated in the blood. When the results of chest radiographs and blood cultures were not included to mimic facilities available at first- level facilities, age 2 - 5 months and weight for age z- score less than) 2 SD remained independent predictors of death.Conclusion When resources are limited, children with lower chest wall indrawing ( severe pneumonia) who are 2 - 5 months old or moderately to severely malnourished should be referred for immediate higher- level care.
Pneumococcal disease (Pnc) is responsible for invasive pneumococcal disease (IPD)--mainly meningitis and septicaemia--and is an infection of public health importance in Europe. Following the licensure of an effective conjugate vaccine (PCV) in Europe, several European countries, including France, Germany, the Netherlands, Norway, Spain and the United Kingdom, are introducing universal Pnc childhood immunisation programmes. As part of a European Union (EU) funded project on pneumococcal disease (Pnc-EURO), a questionnaire was distributed in late 2003 to each of the current 25 European Union member states as well as Norway and Switzerland to get a clearer picture of national surveillance for invasive pneumococcal disease (IPD) in Europe. All respondents were contacted in 2006 and asked to provide an update to the questionnaire. Twenty two of the 27 countries targeted completed and returned the questionnaire. Four of the 22 responding countries have no reporting requirement for IPD. Eighteen countries reported a total of 27 national surveillance systems. Case definitions employed in these systems differed. Fourteen of the 18 countries reported collection of IPD strains to a single reference lab for serotyping and in 12 countries to a single laboratory for susceptibility testing. Thirteen countries undertook laboratory quality assurance. Information on age and sex were widely collected, but only 11/27 systems collected information on pneumococcal polysaccharide vaccine status, while 5/27 systems collected information on pneumococcal conjugate vaccine status. The incidence of IPD reported in each of the 18 countries ranged from 0.4 to 20/100,000 in the general population, with a total of 23,470 IPD cases reported over a 12 month period. Surveillance for IPD in Europe is very heterogeneous. Several countries lack surveillance systems. Large differences in reported disease incidence may reflect both true differences, and also variations in patient and healthcare factors, including surveillance. If IPD surveillance in Europe can be strengthened, countries will be able to make informed decisions regarding the introduction of new pneumococcal vaccines and also to monitor and compare the impact and effectiveness of new programmes.