Treatment outcomes among drug-susceptible tuberculosis patients in Latvia, 2006-2010.

SETTING: Latvia, an Eastern European country with a high burden of tuberculosis (TB). OBJECTIVE: To describe treatment outcomes among new drug-susceptible TB patients and assess the association of treatment outcomes with selected social determinants and risk factors. DESIGN: A retrospective cohort study of patients aged ⩾15 years registered during 2006-2010, with a review of records in the National Tuberculosis Registry. RESULTS: Of 2476 patients, 1704 (69%) were male; the median age was 42 years. About two thirds of patients were unemployed or retired, 7% were human immunodeficiency virus (HIV) positive and 35% had a history of alcohol use. Treatment success was achieved in 2167 (88%) patients. Older age, unemployment, HIV infection and alcohol use were found to be independently associated with unsuccessful treatment (death, loss to follow-up, failure, transfer out and other). For many variables, including HIV infection, diabetes mellitus and tobacco use, it was not possible to distinguish between 'not recorded' and 'not present' in the registry. CONCLUSION: The treatment success rate among new drug-susceptible TB patients exceeded the 85% global target for TB control. Additional attention and support is required for most vulnerable patients, such as those who are unemployed or retired, HIV infected and alcohol users. The National TB Registry should be revised to improve definitions and staff should be trained for proper data collection and recording.

Tick-borne encephalitis in Latvia 1973-2009: epidemiology, clinical features and sequelae.

BACKGROUND AND PURPOSE: To report a 37-year observational experience in Latvia relating the incidence of human tick-borne encephalitis (TBE) and its clinical manifestations, to the field abundance of ticks. METHODS: Tick abundance was measured by standard flagging techniques. Incidence of human tick-borne disease was derived from Public Health reporting data. Clinical and follow-up data were determined from hospital cohorts from 1973 to 2009. RESULTS: Two TBE incidence peaks in the mid-1970s and the 1990s correlated with increased field abundance of ticks. Increased human TBE in the 1970s was associated with higher field abundance of both Ixodes ricinis and I. Persulcatus. The 1990s peak was particularly associated with I. ricinus, the species predominating in western/central Latvia, and with other factors, including changed agricultural land usage. Proportions of patients with meningitic or focal forms of TBE were similar in the two outbreaks and the intervening periods. Meningeal irritation occurred in 90%, altered consciousness in 19%, ataxia in 34%, seizures in 9%, bulbar features in 2-3% and limb weakness in 15% with shoulder amyotrophy predominating in 5%. Annual mortality varied from 0 to 1.3% and was not related to the overall incidence of TBE. Follow-up for 1-13 years of a cohort of 100 patients revealed long-term sequelae in over 50%, more commonly in those suffering focal forms of acute TBE. CONCLUSIONS: Clinical features and mortality of the 1970s and 1990s TBE outbreaks were similar and did not point to a change in virulence.

Increase of cases of legionellosis in Latvia, 2011.

An increased number of legionellosis cases in 2011 has been reported in Latvia, compared to the ten previous years. A total of 30 legionellosis cases (1.35 per 100,000 inhabitants), including 19 females, have been confirmed until the end of September 2011. The majority of cases (n=23) were inhabitants of the capital city Riga. The reason for the increase in legionellosis is unclear. Twenty-six of the 30 cases are not travel-related.

Screening for Corynebacterium diphtheriae and Corynebacterium ulcerans in patients with upper respiratory tract infections 2007-2008: a multicentre European study.

Diphtheria is now rare in most European countries but, when cases do arise, the case fatality rate is high (5-10%). Because few countries continue to routinely screen for the causative organisms of diphtheria, the extent to which they are circulating amongst different European populations is largely unknown. During 2007-2008, ten European countries each screened between 968 and 8551 throat swabs from patients with upper respiratory tract infections. Six toxigenic strains of Corynebacterium diphtheriae were identified: two from symptomatic patients in Latvia (the country with the highest reported incidence of diphtheria in the European Union) and four from Lithuania (two cases, two carriers); the last reported case of diphtheria in Lithuania was in 2002. Carriage rates of non-toxigenic organisms ranged from 0 (Bulgaria, Finland, Greece, Ireland, Italy) to 4.0 per 1000 (95% CI 2.0-7.1) in Turkey. A total of 28 non-toxigenic strains were identified during the study (26 C. diphtheriae, one Corynebacterium ulcerans, one Corynebacterium pseudotuberculosis). The non-toxigenic C. ulcerans strain was isolated from the UK, the country with the highest reported incidence of cases due to C. ulcerans. Of the eleven ribotypes detected, Cluj was seen most frequently in the non-toxigenic isolates and, amongst toxigenic isolates, the major epidemic clone, Sankt-Petersburg, is still in circulation. Isolation of toxigenic C. diphtheriae and non-toxigenic C. diphtheriae and C. ulcerans in highly-vaccinated populations highlights the need to maintain microbiological surveillance, laboratory expertise and an awareness of these organisms amongst public health specialists, microbiologists and clinicians.

Ongoing outbreak of aseptic meningitis in South-Eastern Latvia, June - August 2010.

An outbreak of aseptic meningitis has been ongoing in several areas of Latgale region, in the south-eastern part of Latvia since the end of June 2010. By 9 August 2010, 114 cases had been notified. Most of the cases were registered in the city and amalgamated municipality of Daugavpils and neighbouring territories. According to current evidence, two types of enteroviruses, coxsackie A-9 virus and echovirus 30, are the causative agents of the outbreak.

Assessing the risk of a community outbreak of hepatitis A on blood safety in Latvia, 2008.

Post-transfusion hepatitis A virus (HAV) infection worldwide is considered a sporadic event. An outbreak of HAV infection occurred in Latvia between the end of 2007 and throughout 2008 with more than 2,800 confirmed cases reported over a 13-month period (incidence of 123 per 100,000 population). The majority of reported HAV infection cases were in people over 18 years of age and in people living in the capitalcity, Riga. We estimated that the crude risk for HAV contamination of whole blood supplies in Riga between February and October 2008 ranged from 1.4 to 10.6 per 10,000 donated units. In people under 40 years of age, the risk of receiving an infectious blood transfusion was more than 3.0 per 10,000 recipients between August and October 2008 during the peak of the outbreak. We conclude that there is a previously under-recognised impact of HAV on blood safety during widespread outbreaks of this disease. Estimating the risk of contamination of blood supplies during an infectious disease outbreak scenario is important for fine tuning risk assessments and potentially improving public health practices.

Community-wide outbreak of hepatitis A in Latvia in 2008 - an update.

An outbreak of hepatitis A has been ongoing in Latvia with 2,817 confirmed cases reported between 20 November 2007 and 31 December 2008. Initially the spread of infection was due to transmission among drug users and other high-risk groups, as well as several outbreaks in Riga (affecting a school and a restaurant), but in the second half of the year led to a community-wide increase in the number of cases. Molecular analysis of 100 strains showed that 95 belonged to genotype IA, of which 89 were identical and six were single nucleotide variants of the same sequence.

Community-wide outbreak of hepatitis A in Latvia, in 2008.

Since November 2007, an increase in the number of reported hepatitis A cases has been observed in Latvia. The aim of this report is to provide an update on the descriptive epidemiology of hepatitis A in Latvia and suggest some possible explanations of the recent increase in incidence.