Patient Biochemistry and Treatment Need in Chronic Hepatitis B Virus Infection Across Three Continents: Retrospective Cross-Sectional Cohort Studies

INTRODUCTION

Chronic hepatitis B virus (HBV) infection is associated with significant global morbidity and mortality. Low treatment rates are observed in patients living with HBV; the reasons for this are unclear. This study sought to describe patients' demographic, clinical and biochemical characteristics across three continents and their associated treatment need.

METHODS

This retrospective cross-sectional post hoc analysis of real-world data used four large electronic databases from the United States, United Kingdom and China (specifically Hong Kong and Fuzhou). Patients were identified by first evidence of chronic HBV infection in a given year (their index date) and characterized. An algorithm was designed and applied, wherein patients were categorized as treated, untreated but indicated for treatment and untreated and not indicated for treatment based on treatment status and demographic, clinical, biochemical and virological characteristics (age; evidence of fibrosis/cirrhosis; alanine aminotransferase [ALT] levels, HCV/HIV coinfection and HBV virology markers).

RESULTS

In total, 12,614 US patients, 503 UK patients, 34,135 patients from Hong Kong and 21,614 from Fuzhou were included. Adults (99.4%) and males (59.0%) predominated. Overall, 34.5% of patients were treated at index (range 15.9-49.6%), with nucleos(t)ide analogue monotherapy most commonly prescribed. The proportion of untreated-but-indicated patients ranged from 12.9% in Hong Kong to 18.2% in the UK; almost two-thirds of these patients (range 61.3-66.7%) had evidence of fibrosis/cirrhosis. A quarter (25.3%) of untreated-but-indicated patients were aged ≥ 65 years.

CONCLUSION

This large real-world dataset demonstrates that chronic hepatitis B infection remains a global health concern; despite the availability of effective suppressive therapy, a considerable proportion of predominantly adult patients apparently indicated for treatment are currently untreated, including many patients with fibrosis/cirrhosis. Causes of disparity in treatment status warrant further investigation.

Characteristics, Treatment Patterns, and Clinical Outcomes of Chronic Hepatitis B Across 3 Continents: Retrospective Database Study

INTRODUCTION

The prevalence of chronic hepatitis B virus (HBV) infection is high in many countries; however, robust, real-world epidemiological data are lacking. This study describes the prevalence, characteristics, treatment patterns, and long-term clinical outcomes of patients with chronic HBV infection in the US, Germany, and Taiwan.

METHODS

This was a retrospective cohort analysis of three healthcare/insurance claims databases. Individuals were identified as patients with chronic HBV infection if their records contained HBV diagnostic codes from 1 January 2010 to 31 December 2012 (Germany and Taiwan) or 1 January 2013 (USA). Included patients were indexed on 1 January 2013. Patients' demographics, clinical characteristics, and healthcare utilisation were described. Treatment patterns and long-term clinical outcomes over follow-up (to 31 December 2016 or loss to follow-up) were estimated.

RESULTS

The prevalence of chronic HBV infection was 0.10%, 0.17%, and 2.39% in the US, Germany, and Taiwan respectively. Prevalence was very low in children, increased rapidly in adulthood, and peaked in 50- < 65 year olds before declining in the elderly. More US (16.6%) and German (15.4%) patients were HIV ± HCV coinfected than in Taiwan (4.1%). Baseline clinical characteristics and healthcare utilisation were broadly similar between countries. In total, 19.2%, 11.1%, and 5.9% of non-coinfected adult patients received treatment at index in the US, Germany, and Taiwan, respectively; most frequently with nucleos(t)ide analogue monotherapy (94.4%, 97.2%, 99.8% of treated patients, respectively) and rarely with interferons (0.27%, 1.63%, and 0.06%, respectively). Untreated Taiwanese patients were more likely to remain untreated than elsewhere, and treated Taiwanese patients were less likely to persist with therapy. Generally, the cumulative incidence of long-term clinical outcomes was lowest in Germany.

CONCLUSION

This study provides a contemporary, real-world, intercontinental snapshot of chronic HBV infection. Long-term sequelae occurred in all populations, and treatment levels were low, suggesting an unmet need for (or access to) effective treatments.

Using Climate-HIV to describe real-world clinical outcomes for people living with HIV taking dolutegravir-based regimens

Objectives:

The objective of this study was to describe the real-world use and effectiveness of dolutegravir-based regimens (DBRs) in routine clinical practice in the United Kingdom.

Methods:

Retrospective analysis was conducted using data from four National Health Service trusts using Climate-HIV, an electronic case record system. Eligible patients were aged ≥18 years with HIV-1 infection who were prescribed a DBR from December 2012 to March 2018. Outcome measurements were accessed at DBR initiation and at weeks 24, 48 and 96 and the last recorded visit up to the extraction date (last measurement). The primary endpoint was the proportion of patients with HIV-1 RNA <50 copies/mL at Week 48.

Results:

The study cohort included 934 patients; 337 (36%) were female, 414 (47%) were white and 717 (77%) were treatment experienced (TE). The Kaplan–Meier estimated probability of achieving HIV-1 RNA <50 copies/mL at 48 weeks was 96% for treatment-naive (TN) patients and 86% for TE patients. Median times to viral suppression (<50 copies/mL) were 49 and 57 days for TN and TE patients with detectable baseline viral load, respectively, according to Kaplan–Meier analysis. Median follow-up time was 377 days (interquartile range: 131–683). At last measurement, 87% (809/934) of patients remained on a DBR; among those patients, 681 (84%) had HIV-1 RNA <50 copies/mL.

Conclusions:

High levels of virologic suppression and low rates of discontinuation of DBRs were seen in a large, diverse, UK-based population with HIV-1 infection. These findings are broadly consistent with efficacy data from phase III studies.

92 Reshaping the Diagnostic Pathways for Investigation of Haematuria During and After The COVID-19 Pandemic: Diagnostic Accuracy of Strategies for Detection of Bladder Cancer from The IDENTIFY Cohort Study

Introduction

Diagnostic haematuria services have been reduced due to the COVID-19 pandemic, compromising patient care, and necessitating a more pragmatic pathway.

Method

The IDENTIFY study was an international, prospective, multicentre cohort study of over 11,000 patients referred to secondary care for investigation of haematuria. Using this data, we developed strategies using combinations of imaging and cytology as triage tests to maximise cancer detection within a pragmatic pathway.

Results

8112 patients (74·4%) received an ultrasound or a CT urogram, with or without cytology. 5737 (70·7%) patients had visible haematuria (VH) and 2375 (29·3%) had non-visible haematuria (NVH). Diagnostic test performance was used to determine optimal age cut-offs for four proposed strategies. We recommended proceeding directly to transurethral resection of bladder tumour for patients of any age with positive triage tests for cancer. Patients with negative triage tests under 35-years-old with VH, or under 50-years-old with NVH can safely be discharged without undergoing flexible cystoscopy. The remaining patients may undergo flexible cystoscopy, with a greater priority for older patients to capture high risk bladder cancer.

Conclusions

We suggest diagnostic strategies in patients with haematuria, which focus on detection of bladder cancer, whilst reducing the burden to healthcare services in a resource-limited setting.

Polypharmacy and potential drug-drug interactions for people with HIV in the UK from the Climate-HIV database

Objectives

People with HIV (PWHIV) are likely to need therapies for comorbidities as they age. We assessed risk of drug–drug interactions (DDIs) in PWHIV.

Methods

The Climate‐HIV electronic recording system was used to cross‐sectionally analyse records from PWHIV aged ≥ 18 years attending four UK HIV units with a current antiretroviral (ARV) prescription in February 2018. Antiretroviral and non‐ARV medications were categorized by clinical significance of DDIs (University of Liverpool DDI tool). Potential DDIs were predicted using treatment guidelines for commonly recorded comorbidities.

Results

Among 4630 PWHIV (44% female), 41% were ≥ 50 years old. The average number of non‐ARV comedications increased from < 1 for patients aged ≤ 24 years to > 5 for patients aged ≥ 75 years; 65% were taking one or more non‐ARV comedications. The median (interquartile range) number of non‐ARVs was 1 (0–2) and 2 (1–5) for those aged < 50 and ≥ 50 years, respectively. Common comorbidities/concurrent health conditions occurred more frequently in patients aged ≥ 50 years vs. < 50 (53% vs. 34%). Boosted protease inhibitors were associated with the highest proportion of contraindicated comedications; dolutegravir and raltegravir had the fewest. For non‐ARVs, sildenafil and quetiapine were most likely to result in DDIs. Guideline‐recommended treatments for hepatitis C, hepatitis B, and tuberculosis had the highest proportions of contraindications when combined with ARV regimens, while treatments for hepatitis C, malignancy, and mental health conditions had the highest proportion of combinations potentially causing DDIs requiring dose monitoring or adjustment.

Conclusions

Non‐ARV use by PWHIV is high and increases with age. Treatment decisions for ageing PWHIV should consider guideline recommendations for comorbidities.

Persistence and Adherence to ICS/LABA Drugs in UK Patients with Asthma: A Retrospective New-User Cohort Study

Introduction

Asthma is associated with significant economic burden. Inhaled corticosteroid and long-acting beta₂-agonist (ICS/LABA) combination therapies are considered mainstays of treatment. We describe real-world use of ICS/LABAs by comparing treatment persistence and adherence among patients with asthma in the United Kingdom initiating fluticasone furoate/vilanterol (FF/VI) versus budesonide/formoterol (BUD/FM) or beclometasone dipropionate/formoterol (BDP/FM).

Methods

A retrospective new-user active comparator database study was conducted in the IQVIA Medical Research Database. Propensity score (PS) matching was performed for FF/VI versus BUD/FM, and FF/VI versus BDP/FM. The primary objective was to compare patient treatment persistence (time to discontinuation), while secondary objectives included assessing adherence (mean proportion of days covered [PDC] with medication in the study period) and the proportions of patients achieving ≥ 50% and ≥ 80% PDC.

Results

New users of FF/VI (N = 966), BUD/FM (N = 5931) and BDP/FM (N = 9607) were identified and PS-matched: FF/VI (n = 945) versus BUD/FM (n = 3272), and FF/VI (n = 902) versus BDP/FM (n = 3465). At 12 months, treatment persistence was 69% (FF/VI), 53% (BUD/FM) and 57% (BDP/FM). The likelihood of treatment discontinuation within 12 months after initiation with FF/VI was 35% lower than with BUD/FM and 31% lower than for BDP/FM (both p < 0.001). Mean PDC was higher for FF/VI compared with BUD/FM (77.7 vs 72.4; p < 0.0001) and BDP/FM (78.2 vs 71.0; p < 0.0001). The odds of achieving ≥ 50% and ≥ 80% PDC were greater for FF/VI than for BUD/FM and BDP/FM.

Conclusions

In this study, patients who initiated FF/VI were less likely to discontinue treatment and showed greater treatment adherence versus patients who initiated BUD/FM or BDP/FM.

Electronic supplementary material

The online version of this article (10.1007/s12325-020-01344-8) contains supplementary material, which is available to authorized users.

No increased risk of nephrotoxicity associated with 5-aminosalicylic acid in IBD: a population-based cohort and nested case-control study

BACKGROUND

There is conflicting evidence about nephrotoxicity risk associated with 5-aminosalicylates for treatment of IBD.

AIMS

To determine population-based temporal trends for 5-aminosalicylates and estimated risk of nephrotoxicity associated with 5-aminosalicylate use for ulcerative colitis (UC) and Crohn's disease (CD).

METHODS

Retrospective cohort and nested case-control study, using the Health Improvement Network primary care database linked to hospital discharge coding for patients in England, 1996-2017. Nephrotoxicity risk analysis was a first recorded renal impairment diagnosis adjusted for key variables and was assessed between 2008 and 2017.

RESULTS

A total of 35 601 patients with prevalent UC or CD were included. The proportion of patients prescribed 5-aminosalicylates fell from 83% in 1996-1999 to 71% in 2012-2015 for UC patients and 64% to 45% for CD patients. Thirty per cent of patients had prolonged 5-aminosalicylate use. Between 2008 and 2017, the incident rate of nephrotoxicity was similar and stable for UC (12.6/1000 person-years) and CD (10.9/1000 person-years) patients. Multivariate analysis showed no evidence for association between current prescription of 5-aminosalicylate and nephrotoxicity in UC or CD patients, comparing ≤ 30 days prescription prior to index vs 31-≤180 days. However, active disease, disease duration, concomitant cardiovascular disease or diabetes and nephrotoxic drug use were independently associated with development of nephrotoxicity in UC and CD.

CONCLUSIONS

Despite the paucity of evidence for their benefit, 5-aminosalicylates were prescribed to approximately half of CD patients (30% prolonged therapy). Nephrotoxicity was rare in this patient cohort, and was not associated with 5-aminosalicylate use, but rather with disease status, comorbidity and use of nephrotoxic drugs.

Prevalence of anal fistula in the United Kingdom

BACKGROUND

Anal fistula is a pathological connection between the anal canal and perianal skin, which most commonly develops from an infected anal crypt. While the majority of anal fistulas are idiopathic, they are also associated with Crohn’s disease (CD) and other inflammatory conditions. The prevalence of anal fistula is estimated to be 1-2 per 10000 patients, but population-based studies on anal fistula epidemiology are limited and outdated.

AIM

To assess the prevalence of anal fistula and relevant comorbidities, with and without CD in the United Kingdom and Europe.

METHODS

A retrospective population-representative observational cohort study was performed in The Health Improvement Network (THIN), a United Kingdom primary care database. Mid-year point prevalence of anal fistula was calculated on the first of July for each year between 2014 and 2017. Estimates were calculated for anal fistula overall and by CD status and standardized to the United Kingdom and European population. Prevalence of relevant comorbidities including lymphogranuloma venereum, hidradenitis suppurativa, anal presentation of sexually transmitted diseases, diabetes mellitus, and radiation in the pelvic area was reported.

RESULTS

The United Kingdom-standardized overall point prevalence of anal fistula was 1.80 (95%CI: 1.65-1.94) per 10000 patients in 2017, while the Europe standardized estimate was 1.83 (95%CI: 1.68-1.98) per 10000 patients. Both these standardized point prevalence estimates ranged from 1.89 to 2.36 between 2014-2016. The United Kingdom-standardized point prevalence of anal fistula without CD was 1.35 (95%CI: 1.23-1.48) per 10000 patients, while the Europe-standardized estimate was 1.39 (95%CI: 1.26-1.52) per 10000 patients. In contrast, the standardized point prevalence estimate of anal fistula with CD was lower for both United Kingdom and Europe (0.44; 95%CI United Kingdom: 0.37-0.52, 95%CI Europe: 0.37-0.51) per 10000 patients in 2017. In 2017, 19% of anal fistula patients without CD and 13% of anal fistula patients with CD had at least one relevant comorbidity. These results show that anal fistulas are infrequent in the general population. 24.5% of prevalent anal fistulas are associated with CD, but other potentially etiological comorbidities are rare.

CONCLUSION

This real-world evidence study estimated the United Kingdom-standardized prevalence of anal fistula was 1.80 per 10000 patients in 2017. Approximately 25% of cases may be associated with CD, while other comorbidities are rare.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Burden of allergic respiratory disease: a systematic review

This meta-analysis compared the health-related quality of life (HRQL) of patients with allergic rhinitis (AR) and/or allergic asthma (AA) caused by perennial house dust mite (HDM) versus AR and/or AA caused by seasonal pollen allergy. Following a systematic search, the identified studies used the disease-specific rhinitis quality of life questionnaire or generic instruments (SF-36 and SF-12). Summary estimates obtained by meta-analysis showed that HRQL in patients with perennial HDM allergy was significantly worse than that of patients with seasonal pollen allergy, when measured by both disease-specific and generic HRQL instruments, and was reflected by an impact on both physical and mental health. A systematic review of cost data on AR and AA in selected European countries demonstrated that the majority of the economic burden was indirectly caused by high levels of absenteeism and presenteeism; there was little or no evidence of increasing or decreasing cost trends. Increased awareness of the detrimental effects of AR and/or AA on patients’ HRQL and its considerable cost burden might encourage early diagnosis and treatment, in order to minimize the disease burden and ensure beneficial and cost-effective outcomes.

Evaluation of exposure to pioglitazone and risk of prostate cancer: a nested case-control study

OBJECTIVES

Investigate potential association between pioglitazone exposure and risk of prostate cancer.

RESEARCH DESIGN AND METHODS

Nested, matched case-control study. UK primary care data (Clinical Practice Research Datalink (CPRD) GOLD) linked to inpatient (Hospital Episode Statistics (HES)) and cancer registry (National Cancer Information Network (NCIN)) data. English men aged ≥40 years diagnosed with type 2 diabetes mellitus, January 1, 2001 to January 5, 2015. Cases, with prostate cancer diagnosis, matched with up to 4 controls by age, cohort entry date and region. ORs for association of exposure to pioglitazone to incident prostate cancer, adjusted for potential confounders.

RESULTS

From a cohort of 47 772 men with 243 923 person-years follow-up, 756 definite cases of prostate cancer were identified. Incidence was 309.9/100 000 person-years (95% CI 288.6 to 332.8). Pioglitazone use was not associated with prostate cancer risk; adjusted OR 0.759, 95% CI 0.502 to 1.148. Analyses showed no difference when possible cases, prostate cancer in CPRD GOLD only, included (adjusted OR 0.726, 95% CI 0.510 to 1.034). No association when adjusted for channeling bias (OR 0.778, 95% CI 0.511 to 1.184) or limited to an index date prior to July 1, 2011 (adjusted OR 0.508, 95% CI 0.294 to 0.879), despite prostate-specific antigen screening occurring more frequently among cases than controls (81.6% of 756 definite cases cf. 24.2% of 2942 controls (p<0.01)). No association with duration of pioglitazone use, increasing pioglitazone dose or increasing time since initiation.

CONCLUSIONS

In this real-world, nested matched case-control study, exposure to pioglitazone was not associated with increased risk of prostate cancer.

Timeliness of electronic reporting and acceptability of public health follow-up of routine nonparatyphoidal and nontyphoidal Salmonella infections, London and South East England, 2010 to 2011

Nonparatyphoidal and nontyphoidal Salmonella (NTS) infections are major causes of food poisoning in England. Diagnostic laboratories and clinicians have a statutory responsibility to report NTS infection cases to the Health Protection Agency via various means, with electronic reporting encouraged as the universal method. The Health Protection Agency (Public Health England since 1 April 2013) refers cases to environmental health departments for follow-up. Timeliness of reporting and adequacy of NTS infection case follow-up are key factors in the implementation of public health actions. Laboratories, health protection units, and environmental health departments in London and South East (SE) regions of England completed three surveys between December 2010 and April 2011, collecting data about the NTS infection case reporting methods and the time elapsed between symptom onset and public health actions. The median period between symptom onset and public health investigation was 25 days in London and 23 days in SE when electronic reporting was used and 12 days in London and 11 days in SE when other means of reporting were used. The most common follow-up method was a telephone questionnaire in London (53%) and a postal questionnaire in SE (52%). The telephone questionnaire had the highest response rate (98% in London; 96% in SE). Timeliness and efficiency of electronic NTS infection case reports can be improved by decreasing the electronic laboratory report period and using telephone-administered questionnaires to maximize the public health benefit when following up single cases of NTS infection.

Ongoing outbreak of Shigella flexneri serotype 3a in men who have sex with men in England and Wales, data from 2009–2011

Diagnoses of Shigella flexneri in the United Kingdom (UK) are usually travel-related. However, since 2009, there has been an overall increase in UK-acquired cases. The Health Protection Agency has been investigating a national outbreak of S. flexneri detected in 2011 and which is still ongoing. Cases occurred mostly in men who have sex with men and were of serotype 3a. The investigation aimed at obtaining epidemiological data to inform targeted outbreak management and control.

Ongoing outbreak of Shigella flexneri serotype 3a in men who have sex with men in England and Wales, data from 2009-2011

Diagnoses of Shigella flexneri in the United Kingdom (UK) are usually travel-related. However, since 2009, there has been an overall increase in UK-acquired cases. The Health Protection Agency has been investigating a national outbreak of S. flexneri detected in 2011 and which is still ongoing. Cases occurred mostly in men who have sex with men and were of serotype 3a. The investigation aimed at obtaining epidemiological data to inform targeted outbreak management and control.

Poliomyelitis outbreak, Pointe-Noire, Republic of the Congo, September 2010-February 2011

On November 4, 2010, the Republic of the Congo declared a poliomyelitis outbreak. A cross-sectional survey in Pointe-Noire showed poor sanitary conditions and low vaccination coverage (55.5%), particularly among young adults. Supplementary vaccination should focus on older age groups in countries with evidence of immunity gaps.

An increase in the number of mumps cases in the Czech Republic, 2005-2006

The Czech Republic has had a two-dose measles, mumps and rubella (MMR) vaccination programme since 1987. The last outbreak of mumps was reported in 2002, but an increase in the number of mumps cases was observed in 2005, starting in October that year. We analysed routinely collected surveillance data from 1 January 2005 to 30 June 2006 to show the magnitude of the increase and describe the most affected groups in order to better target prevention and control strategies. In the 18-month period examined, 5,998 cases of mumps were notified, with a peak incidence in May 2006. No deaths were recorded, but 21% of cases were hospitalised. Incidence was lowest in the Plzeň region (1.9/100,000) and highest in Zlín (118.6/100,000). There were more male (61.8%) than female cases. The age of the cases ranged from 0 to 80 years. The highest incidence rate was observed in the age group of 15 to 19 years, in which 87% of cases had received two doses of mumps vaccine. The average age of unvaccinated cases was 22.9 years, while for cases vaccinated with two doses it was 14.5 years. Although vaccine effectiveness could not be calculated from the data available, possible reasons for highly-vaccinated cases occurring are discussed.

An increase in the number of mumps cases in the Czech Republic, 2005-2006

The Czech Republic has had a two-dose measles, mumps and rubella (MMR) vaccination programme since 1987. The last outbreak of mumps was reported in 2002, but an increase in the number of mumps cases was observed in 2005, starting in October that year. We analysed routinely collected surveillance data from 1 January 2005 to 30 June 2006 to show the magnitude of the increase and describe the most affected groups in order to better target prevention and control strategies. In the 18-month period examined, 5,998 cases of mumps were notified, with a peak incidence in May 2006. No deaths were recorded, but 21% of cases were hospitalised. Incidence was lowest in the Plzen region (1.9/100,000) and highest in Zlin (118.6/100,000). There were more male (61.8%) than female cases. The age of the cases ranged from 0 to 80 years. The highest incidence rate was observed in the age group of 15 to 19 years, in which 87% of cases had received two doses of mumps vaccine. The average age of unvaccinated cases was 22.9 years, while for cases vaccinated with two doses it was 14.5 years. Although vaccine effectiveness could not be calculated from the data available, possible reasons for highly-vaccinated cases occurring are discussed.

Current measles outbreak in Serbia: a preliminary report

An outbreak of measles is ongoing in northern Serbia. The first cases were in January 2007 in the area of Novi Sad in the autonomous province of Vojvodina. As of 12 March 2007, 121 suspected cases had been reported to the regional Institute of Public Health.

Two clusters of human infection with influenza A/H5N1 virus in the Republic of Azerbaijan, February–March 2006

Following the appearance of influenza A/H5 virus infection in several wild and domestic bird species in the Republic of Azerbaijan in February 2006, two clusters of potential human avian influenza due to A/H5N1 (HAI) cases were detected and reported by the Ministry of Health (MoH) to the World Health Organization (WHO) Regional Office for Europe during the first two weeks of March 2006. On 15 March 2006, WHO led an international team, including infection control, clinical management, epidemiology, laboratory, and communications experts, to support the MoH in investigation and response activities. As a result of active surveillance, 22 individuals, including six deaths, were evaluated for HAI and associated risk infections in six districts. The investigations revealed eight cases with influenza A/H5N1 virus infection confirmed by a WHO Collaborating Centre for Influenza and one probable case for which samples were not available. The cases were in two unrelated clusters in Salyan (seven laboratory confirmed cases, including four deaths) and Tarter districts (one confirmed case and one probable case, both fatal). Close contact with and de-feathering of infected wild swans was considered to be the most plausible source of exposure to influenza A/H5N1 virus in the Salyan cluster, although difficulties in eliciting information were encountered during the investigation, because of the illegality of some of the activities that might have led to the exposures (hunting and trading in wild birds and their products). These cases constitute the first outbreak worldwide where wild birds were the most likely source of influenza A/H5N1 virus infection in humans. The rapid mobilisation of resources to contain the spread of influenza A/H5 in the two districts was achieved through collaboration between the MoH, WHO and its international partners. Control activities were supported by the establishment of a field laboratory with real-time polymerase chain reaction (RT-PCR) capacity to detect influenza A/H5 virus. Daily door-to-door surveillance undertaken in the two affected districts made it unlikely that human cases of influenza A/H5N1 virus infection remained undetected.

Application of pulsed-field gel electrophoresis to identify potential outbreaks of campylobacteriosis in New Zealand

Since 2002, New Zealand's incidence of campylobacteriosis has exceeded 300 cases per 100,000 people per annum. To evaluate genetic variation in human isolates, 183 Campylobacter isolates were collected from a single clinical laboratory in Christchurch: 77 during an 8-week period in spring, and the rest 3 months later over a second 8-week period in autumn. Isolates were identified to the species level and subtyped using Penner serotyping (Campylobacter jejuni only) and pulsed-field gel electrophoresis (PFGE) using both SmaI and KpnI. Approximately two-thirds of the isolates could be grouped into clusters of between 2 and 26 isolates with indistinguishable SmaI and KpnI patterns. Less than 10% of the isolates were of the same type between the two sampling periods. The epidemiological relevance of the PFGE clusters was supported by temporal clustering, some spatial clustering, and some statistically significant demographic similarities among cases in a cluster. Conversely, patient cases yielding isolates which did not cluster with isolates from other cases were more likely to report recent overseas travel and less likely to live within larger urban centers. To identify whether these clusters actually represent common-source outbreaks, however, would require the detailed, rapid, and reiterative epidemiological investigation of cases within a PFGE cluster. The combined and timely application of subtyping and epidemiological investigation would appear to be a promising strategy for understanding campylobacteriosis in New Zealand.

Two clusters of human infection with influenza A/H5N1 virus in the Republic of Azerbaijan, February-March 2006

Following the appearance of influenza A/H5 virus infection in several wild and domestic bird species in the Republic of Azerbaijan in February 2006, two clusters of potential human avian influenza due to A/H5N1 (HAI) cases were detected and reported by the Ministry of Health (MoH) to the World Health Organization (WHO) Regional Office for Europe during the first two weeks of March 2006. On 15 March 2006, WHO led an international team, including infection control, clinical management, epidemiology, laboratory, and communications experts, to support the MoH in investigation and response activities. As a result of active surveillance, 22 individuals, including six deaths, were evaluated for HAI and associated risk infections in six districts. The investigations revealed eight cases with influenza A/H5N1 virus infection confirmed by a WHO Collaborating Centre for Influenza and one probable case for which samples were not available. The cases were in two unrelated clusters in Salyan (seven laboratory confirmed cases, including four deaths) and Tarter districts (one confirmed case and one probable case, both fatal). Close contact with and de-feathering of infected wild swans was considered to be the most plausible source of exposure to influenza A/H5N1 virus in the Salyan cluster, although difficulties in eliciting information were encountered during the investigation, because of the illegality of some of the activities that might have led to the exposures (hunting and trading in wild birds and their products). These cases constitute the first outbreak worldwide where wild birds were the most likely source of influenza A/H5N1 virus infection in humans. The rapid mobilisation of resources to contain the spread of influenza A/H5 in the two districts was achieved through collaboration between the MoH, WHO and its international partners. Control activities were supported by the establishment of a field laboratory with real-time polymerase chain reaction (RT-PCR) capacity to detect influenza A/H5 virus. Daily door-to-door surveillance undertaken in the two affected districts made it unlikely that human cases of influenza A/H5N1 virus infection remained undetected.