Respiratory failure among patients with COVID-19 in Jiangsu province, China: a multicentre retrospective cohort study.

This study was a retrospective multicentre cohort study of patients with coronavirus disease 2019 (COVID-19) diagnosed at 24 hospitals in Jiangsu province, China as of 15 March 2020. The primary outcome was the occurrence of acute respiratory failure during hospital stay. Of 625 patients, 56 (9%) had respiratory failure. Some selected demographic, epidemiologic, clinical and laboratory features as well as radiologic features at admission and treatment during hospitalisation were significantly different in patients with and without respiratory failure. The multivariate logistic analysis indicated that age (in years) (odds ratio [OR], 1.07; 95% confidence interval [CI]: 1.03-1.10; P = 0.0002), respiratory rate (breaths/minute) (OR, 1.23; 95% CI: 1.08-1.40; P = 0.0020), lymphocyte count (109/l) (OR, 0.18; 95% CI: 0.05-0.69; P = 0.0157) and pulmonary opacity score (per 5%) (OR, 1.38; 95% CI: 1.19-1.61; P < 0.0001) at admission were associated with the occurrence of respiratory failure. Older age, increased respiratory rate, decreased lymphocyte count and greater pulmonary opacity score at admission were independent risk factors of respiratory failure in patients with COVID-19. Patients having these risk factors need to be intensively managed during hospitalisation.

An assessment of the doses received by members of the public in Japan following the nuclear accident at Fukushima Daiichi nuclear power plant.

The earthquake and tsunami on 11 March 2011, centred off the east coast of Japan, caused considerable destruction and substantial loss of life along large swathes of the Japanese coastline. The tsunami damaged the Fukushima Daiichi nuclear power plant (NPP), resulting in prolonged releases of radioactive material into the environment. This paper assesses the doses received by members of the public in Japan. The assessment is based on an estimated source term and atmospheric dispersion modelling rather than monitoring data. It is evident from this assessment that across the majority of Japan the estimates of dose are very low, for example they are estimated to be less than the annual average dose from natural background radiation in Japan. Even in the regions local to Fukushima Daiichi NPP (and not affected by any form of evacuation) the maximum lifetime effective dose is estimated to be well below the cumulative natural background dose over the same period. The impact of the urgent countermeasures on the estimates of dose was considered. And the relative contribution to dose from the range of exposure pathways and radionuclides were evaluated. Analysis of estimated doses focused on the geographic irregularity and the impact of the meteorological conditions. For example the dose to an infant's thyroid received over the first year was estimated to be greater in Hirono than in the non-evacuated region of Naraha, despite Hirono being further from the release location. A number of factors were identified and thought to contribute towards this outcome, including the local wind pattern which resulted in the recirculation of part of the release. The non-uniform nature of dose estimates strengthens the case for evaluations based on dispersion modelling.

Household carbon monoxide (CO) concentrations in a large African city: An unquantified public health burden?

Carbon monoxide (CO) is a poisonous gas produced by incomplete combustion of carbon-based fuels that is linked to mortality and morbidity. Household air pollution from burning fuels on poorly ventilated stoves can lead to high concentrations of CO in homes. There are few datasets available on household concentrations of CO in urban areas of sub-Saharan African countries. CO was measured every minute over 24 h in a sample of homes in Nairobi, Kenya. Data on household characteristics were gathered by questionnaire. Metrics of exposure were summarised and analysis of temporal changes in concentration was performed. Continuous 24-h data were available from 138 homes. The mean (SD), median (IQR) and maximum 24-h CO concentration was 4.9 (6.4), 2.8 (1.0-6.3) and 44 ppm, respectively. 50% of homes had detectable CO concentrations for 847 min (14h07m) or longer during the 24-h period, and 9% of homes would have activated a CO-alarm operating to European specifications. An association between a metric of total CO exposure and self-reported exposure to vapours >15 h per week was identified, however this were not statistically significant after adjustment for the multiple comparisons performed. Mean concentrations were broadly similar in homes from a more affluent area and an informal settlement. A model of typical exposure suggests that cooking is likely to be responsible for approximately 60% of the CO exposure of Nairobi schoolchildren. Household CO concentrations are substantial in Nairobi, Kenya, despite most homes using gas or liquid fuels. Concentrations tend to be highest during the evening, probably associated with periods of cooking. Household air pollution from cooking is the main source of CO exposure of Nairobi schoolchildren. The public health impacts of long-term CO exposure in cities in sub-Saharan Africa may be considerable and should be studied further.

Association between lung function and dyspnoea and its variation in the multinational Burden of Obstructive Lung Disease (BOLD) study.

BACKGROUND: Dyspnoea is a common symptom of respiratory disease. However, data on its prevalence in general populations and its association with lung function are limited and are mainly from high-income countries. The aims of this study were to estimate the prevalence of dyspnoea across several world regions, and to investigate the association of dyspnoea with lung function. METHODS: Dyspnoea was assessed, and lung function measured in 25,806 adult participants of the multinational Burden of Obstructive Lung Disease study. Dyspnoea was defined as ≥2 on the modified Medical Research Council (mMRC) dyspnoea scale. The prevalence of dyspnoea was estimated for each of the study sites and compared across countries and world regions. Multivariable logistic regression was used to assess the association of dyspnoea with lung function in each site. Results were then pooled using random-effects meta-analysis. RESULTS: The prevalence of dyspnoea varied widely across sites without a clear geographical pattern. The mean prevalence of dyspnoea was 13.7 % (SD=8.2 %), ranging from 0 % in Mysore (India) to 28.8 % in Nampicuan-Talugtug (Philippines). Dyspnoea was strongly associated with both spirometry restriction (FVC

Perspectives of TB survivors and policymakers on post-TB disability.

BACKGROUND: An international multistakeholder participatory workshop was hosted in the Gambia, West Africa, in November 2021. OBJECTIVES: To explore the experiences, challenges and recommendations of workshop participants on health and wellbeing after TB treatment. METHODS: An exploratory, descriptive, qualitative approach was used for data collection through facilitator-guided group discussions. Workshop participants included adolescent and adult TB survivors, and representatives of TB advocacy groups and the policy sector. Discussions were audio-recorded and transcribed verbatim, and the data were analysed using a deductive thematic approach. RESULTS: Overall, 38 participants (22 women) from six West African countries participated in the workshop, comprising 33 TB survivors and advocacy group representatives and 5 participants from the policy sector. Although some TB survivors noted improved ability to carry out physical activities, others continued to experience detrimental effects on their family life, social interactions, physical health and ongoing stigma. Policymakers emphasised the lack of data and clear guidelines on post-TB disability. CONCLUSIONS: Some TB survivors continue to suffer detrimental effects of the illness even after treatment completion. However, available data on post-TB disability is inadequate to support policy adoption. Therefore, there is an urgent need for increased advocacy, awareness and research to bridge knowledge gaps.

CONTEXTE: Un atelier participatif international multipartite a été organisé en Gambie, Afrique de l'Ouest, en novembre 2021. OBJECTIFS: Analyser les expériences, les défis et les recommandations des participants à l'atelier en matière de santé et de bien-être après un traitement antituberculeux. MÉTHODES: Une approche exploratoire, descriptive et qualitative a été utilisée pour le recueil des données par le biais de discussions de groupe encadrées par un animateur. Les participants à l'atelier étaient des adolescents et des adultes ayant survécu à une TB, ainsi que des représentants de groupes de plaidoyer de la TB et du secteur politique. Les discussions ont été enregistrées sur support audio et transcrites textuellement, et les données ont été analysées en utilisant une approche thématique déductive. RÉSULTATS: Au total, 38 participants (22 femmes) de six pays d'Afrique de l'Ouest ont participé à l'atelier, dont 33 représentants de groupes de plaidoyer ayant eux-mêmes survécu à une TB et 5 participants issus du secteur politique. Bien que certaines personnes ayant survécu à une TB aient constaté une amélioration de leur capacité à mener des activités physiques, d'autres ont continué à subir les effets néfastes sur leur vie familiale, leurs interactions sociales, leur santé physique et la stigmatisation permanente. Les responsables politiques ont souligné le manque de données et de directives claires sur le handicap post-TB. CONCLUSIONS: Certaines personnes ayant survécu à une TB continuent de subir les effets néfastes de la maladie, et ce même après la fin du traitement. Cependant, les données disponibles sur le handicap post-TB sont insuffisantes pour soutenir l'adoption de politiques. Il est donc urgent de renforcer le plaidoyer, la sensibilisation et la recherche pour combler les lacunes en matière de connaissances.

Decreased prevalence and severity of asthma symptoms among adolescents in Ibadan, Nigeria, 1995-2018.

BACKGROUND: Phases I and III of the International Study of Asthma and Allergies in Childhood (ISAAC) documented increased asthma symptoms among Nigerian 13-14-year old adolescents. We investigated the trend further using the Global Asthma Network (GAN) surveillance.METHODS: Using ISAAC methodology, GAN Phase I data on symptoms and risk factors for asthma and asthma management were obtained from February to July 2018.RESULTS: There were 2,897 adolescents from 23 secondary schools. For current wheeze, there was an absolute prevalence fall per decade of -1.4 with -1 standard error (SE) in 16 years from 2002 (ISAAC Phase III) to 2018 (GAN Phase I). This pattern was evident for prevalence of reported asthma ever, severe asthma symptoms and night cough with ≥1 SE. During the 23-year interval between ISAAC Phase I and GAN Phase I, there was a fall (≥1 SE) in the absolute prevalence of reported asthma ever, severe asthma symptoms and night cough, except for severe asthma symptoms (-0.2 SE). Respectively 36% and 43% of symptomatic adolescents purchased and used salbutamol and prednisolone.CONCLUSION: The prevalence and severity of asthma symptoms remain high among adolescents in Ibadan. This could be mitigated by improved access to affordable and effective asthma treatments.

Prevalence and determinants of chronic respiratory diseases in adults in Sudan.

BACKGROUND: Chronic respiratory diseases (CRDs) are considered a significant cause of morbidity and mortality worldwide, although data from Africa are limited. This study aimed to determine the prevalence and determinants of CRDs in Khartoum, Sudan.METHODS: Data were collected from 516 participants aged ≥40 years, who had completed a questionnaire and undertook pre- and post-bronchodilator spirometry testing. Trained field workers administered the questionnaires and conducted spirometry. Survey-weighted prevalence of respiratory symptoms and spirometric abnormalities were estimated. Regression analysis models were used to identify risk factors for chronic lung diseases.RESULTS: Using the Third National Health and Nutrition Examination Survey, 1988-1994 (NHANES III) reference equations, the prevalence of chronic airflow obstruction (CAO) was 10%. The main risk factor was older age, 60-69 years (OR 3.16, 95% CI 1.20-8.31). Lower education, high body mass index and a history of TB were also identified as significant risk factors. The prevalence of a low forced vital capacity (FVC) using NHANES III was 62.7% (SE 2.2) and 11.3% (SE 1.4) using locally derived values.CONCLUSION: The prevalence of spirometric abnormality, mainly low FVC, was high, suggesting that CRD is of substantial public health importance in urban Sudan. Strategies for the prevention and control of these problems are needed.

Prevalence and determinants of chronic respiratory diseases in adults in rural Sudan.

BACKGROUND: Chronic respiratory diseases (CRDs) greatly contribute to worldwide mortality. Despite new data emerging from Africa, prevalence estimates and determinants of CRDs in rural settings are limited. This study sought to extend the existing research conducted in urban Sudan by conducting a rural comparison.METHODS: Participants aged ≥18 years (n = 1,850), living in rural Gezira State completed pre-and post-bronchodilator spirometry and a questionnaire. Prevalence of respiratory symptoms and spirometric abnormalities were reported. Regression analyses were used to identify risk factors for CRDs.RESULTS: Prevalence of chronic airflow obstruction (CAO) was 4.1% overall and 5.5% in those aged ≥40 years. Reversibility was seen in 6.4%. Low forced vital capacity (FVC) was seen in 58.5%, and at least one respiratory symptom was present in 40.7% of the participants. CAO was more common among people aged 60-69 years (OR 2.07, 95% CI 1.13-3.82) and less common among highly educated participants (OR 0.50, 95% CI 0.27-0.93). Being underweight was associated with lower FVC (OR 3.07, 95% CI 2.24-4.20).CONCLUSIONS: A substantial burden of CRD exists among adults in rural Sudan. Investment in CRD prevention and management strategies is needed.

Post-TB health and wellbeing.

TB affects around 10.6 million people each year and there are now around 155 million TB survivors. TB and its treatments can lead to permanently impaired health and wellbeing. In 2019, representatives of TB affected communities attending the '1st International Post-Tuberculosis Symposium´ called for the development of clinical guidance on these issues. This clinical statement on post-TB health and wellbeing responds to this call and builds on the work of the symposium, which brought together TB survivors, healthcare professionals and researchers. Our document offers expert opinion and, where possible, evidence-based guidance to aid clinicians in the diagnosis and management of post-TB conditions and research in this field. It covers all aspects of post-TB, including economic, social and psychological wellbeing, post TB lung disease (PTLD), cardiovascular and pericardial disease, neurological disability, effects in adolescents and children, and future research needs.

Chronic obstructive pulmonary disease in sub-Saharan Africa.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide and an important cause of death in sub-Saharan Africa (SSA). We conducted a systematic review and meta-analysis on the prevalence of and risk factors for COPD in SSA.METHODS: We conducted a protocol-driven systematic literature search in MEDLINE, EMBASE, CINAHL and Global Health, supplemented by a manual search of the abstracts from thoracic conference proceedings from 2017 to 2020. We did a meta-analysis of COPD prevalence and its association with current smoking.RESULTS: We identified 831 titles, of which 27 were eligible for inclusion in the review and meta-analysis. The population prevalence of COPD ranged from 1.7% to 24.8% (pooled prevalence: 8%, 95% CI 6-11). An increased prevalence of COPD was associated with increasing age, smoking and biomass smoke exposure. The pooled odds ratio for the effect of current smoking (vs. never smoked) on COPD was 2.20 (95% CI 1.62-2.99).CONCLUSION: COPD causes morbidity and mortality in adults in SSA. Smoking is an important risk factor for COPD in SSA, and this exposure needs to be reduced through the combined efforts of clinicians, researchers and policymakers to address this debilitating and preventable lung disease.

Household air pollution and COPD: cause and effect or confounding by other aspects of poverty?

SETTING: Household air pollution (HAP) and chronic obstructive pulmonary disease (COPD) are both major public health problems, reported to cause around 4 million and 3 million deaths every year, respectively. The great majority of these deaths, as well as the burden of disease during life is felt by people in low- and middle-income countries (LMICs).OBJECTIVE and DESIGN: The extent to which HAP causes COPD is controversial; we therefore undertook this review to offer a viewpoint on this from the Global Initiative for COPD (GOLD).RESULTS: We find that while COPD is well-defined in many studies on COPD and HAP, there are major limitations to the definition and measurement of HAP. It is thus difficult to disentangle HAP from other features of poverty that are themselves associated with COPD. We identify other limitations to primary research studies, including the use of cross-sectional designs that limit causal inference.CONCLUSION: There is substantial preventable morbidity and mortality associated with HAP, COPD and poverty, separately and together. Although it may not be possible to define clear causal links between HAP and COPD, there is a clear urgency to reduce the avoidable burden of disease these inflict on the world´s poor.

Chronic respiratory disease in adult outpatients in three African countries: a cross-sectional study.

BACKGROUND: The greatest burden of chronic respiratory disease is in low- and middle-income countries, with recent population-based studies reporting substantial levels of obstructive and restrictive lung function.OBJECTIVE: To characterise the common chronic respiratory diseases encountered in hospital outpatient clinics in three African countries.METHODS This was a cross-sectional study of consecutive adult patients with chronic respiratory symptoms (>8 weeks) attending hospital outpatient departments in Ethiopia, Kenya and Sudan. Patients were assessed using a respiratory questionnaire, spirometry and chest radiography. The diagnoses of the reviewing clinicians were ascertained.RESULT: A total of 519 patients (209 Kenya, 170 Ethiopia, 140 Sudan) participated; the mean age was 45.2 years (SD 16.2); 53% were women, 83% had never smoked. Reviewing clinicians considered that 36% (95% CI 32-40) of patients had asthma, 25% (95% CI 21-29) had chronic bronchitis, 8% (95% CI 6-11) chronic obstructive pulmonary disease (COPD), 5% (95% CI 4-8) bronchiectasis and 4% (95% CI 3-6) post-TB lung disease. Spirometry consistent with COPD was present in 35% (95% CI 30-39). Restriction was evident in 38% (95% CI 33-43). There was evidence of sub-optimal diagnosis of asthma and COPD.CONCLUSION: In Ethiopia, Kenya and Sudan, asthma, COPD and chronic bronchitis account for the majority of diagnoses in non-TB patients with chronic respiratory symptoms. The suboptimal diagnosis of these conditions will require the widespread use of spirometry.

Improving access to affordable quality-assured inhaled medicines in low- and middle-income countries.

BACKGROUND: Access to affordable inhaled medicines for chronic respiratory diseases (CRDs) is severely limited in low- and middle-income countries (LMICs), causing avoidable morbidity and mortality. The International Union Against Tuberculosis and Lung Disease convened a stakeholder meeting on this topic in February 2022.METHODS: Focused group discussions were informed by literature and presentations summarising experiences of obtaining inhaled medicines in LMICs. The virtual meeting was moderated using a topic guide around barriers and solutions to improve access. The thematic framework approach was used for analysis.RESULTS: A total of 58 key stakeholders, including patients, healthcare practitioners, members of national and international organisations, industry and WHO representatives attended the meeting. There were 20 pre-meeting material submissions. The main barriers identified were 1) low awareness of CRDs; 2) limited data on CRD burden and treatments in LMICs; 3) ineffective procurement and distribution networks; and 4) poor communication of the needs of people with CRDs. Solutions discussed were 1) generation of data to inform policy and practice; 2) capacity building; 3) improved procurement mechanisms; 4) strengthened advocacy practices; and 5) a World Health Assembly Resolution.CONCLUSION: There are opportunities to achieve improved access to affordable, quality-assured inhaled medicines in LMICs through coordinated, multi-stakeholder, collaborative efforts.

Availability of diagnostic services and essential medicines for non-communicable respiratory diseases in African countries.

BACKGROUND: The global burden of disease due to asthma and chronic obstructive pulmonary disease (COPD) is substantial and particularly great in low- and middle-income countries, including many African countries. Management is affected by availability of diagnostic tests and essential medicines. The study aimed to explore the availability of spirometry services and essential medicines for asthma and COPD in African countries.METHOD: Questionnaires were delivered to healthcare workers at the annual meeting of the Pan African Thoracic Society Methods in Epidemiology and Clinical Research (PATS MECOR) and International Multidisciplinary Programme to Address Lung Health and TB in Africa (IMPALA). Data were analysed using simple descriptive statistics.RESULTS: A total of 37 questionnaires representing 13 African countries were returned. Spirometry availability was 73.0%. The most common reasons for non-availability were lack of knowledge of the utility of the test. Within the study sample, 33.3% faced sporadic availability due to maintenance issues. Essential medicines availability ranged from 37.8% for inhaled corticosteroid-long-acting beta-agonist inhalers to 100% for prednisolone 5 mg tablets, mainly due to supply chain problems.CONCLUSION: There is varied availability of spirometry and WHO essential medicines for COPD and asthma in African countries. Strategies are needed to improve access to basic effective care for people with non-communicable lung disease in Africa.

Respiratory presentations to acute services at a tertiary hospital in South Africa.

BACKGROUND: Respiratory diseases account for >10% of the global burden of disease when measured in disability-adjusted life-years. The burden of chronic respiratory diseases (CRDs) increases as the world's population ages, with a much greater increase in low- to middle-income countries. OBJECTIVES: To characterise and quantify the reasons for acute respiratory presentations to the acute care services at a tertiary hospital in Cape Town, South Africa. METHODS: A cross-sectional descriptive study was conducted. Casualty registers and electronic record databases were reviewed to determine the diagnoses of consecutive patients attending the casualty unit from May 2019 to January 2020. RESULTS: A total of 1 053 individual patients presented with a primary respiratory diagnosis. Fewer than 10% of admissions were from outside the Cape Town metropole, while >60% were from the subdistrict immediately adjacent to the hospital. Of all patients, 8.3% were readmitted at least once within the 9-month study period. Six hundred and forty-three (61.1%) of the patients presented with non-CRDs. The main reasons for presentation in these patients were pulmonary tuberculosis (PTB) (n=224; 21.3%), other infections including lower respiratory tract infections, pneumonia and bronchitis (n=272; 25.8%), and cancer (n=140; 13.3%). Haemoptysis was seen in 9.8% of all patients, mainly explained by post-tuberculosis lung disease (PTLD) (37.9%) and PTB (36.9%). Of the patients, 410 (38.9%) had an underlying CRD, with chronic pulmonary obstructive disease (COPD) being the most common (n=192; 18.2%), followed by PTLD (n=88; 8.5%) and asthma (n=52; 5.1%). CONCLUSIONS: Over a 9-month period, acute respiratory presentations to a tertiary hospital were mainly for primary/secondary level of care indications, highlighting disparity in accessing tertiary services. COPD and PTLD predominated among CRDs, while infections and cancers were common. A high readmission rate was found for several diseases, suggesting the potential for targeted interventions to prevent both admissions and readmissions and reduce acute hospital utilisation costs.

Persistent chronic respiratory symptoms despite TB cure is poorly correlated with lung function.

BACKGROUND: Persistent respiratory symptoms and lung function deficits are common after patients with TB. We aimed to define the burden of post-TB lung disease (PTLD) and assess associations between symptoms and impairment in two high TB incidence communities.METHODS: This was a cross-sectional survey of adults in Cape Town, South Africa who completed TB treatment 1-5 years previously. Questionnaires, spirometry and 6-minute walking distance (6MWD) were used to assess relationships between outcome measures and associated factors.RESULTS: Of the 145 participants recruited (mean age: 42 years, range: 18-75; 55 [38%] women), 55 (38%) had airflow obstruction and 84 (58%) had low forced vital capacity (FVC); the mean 6MWD was 463 m (range: 240-723). Respiratory symptoms were common: chronic cough (n = 27, 19%), wheeze (n = 61, 42%) and dyspnoea (modified MRC dyspnoea score 3 or 4: n = 36, 25%). There was poor correlation between FVC or obstruction and 6MWD. Only low body mass index showed consistent association with outcomes on multivariable analyses. Only 19 (13%) participants had a diagnosis of respiratory disease, and 16 (11%) currently received inhalers.CONCLUSION: There was substantial burden of symptoms and physiological impairment in this "cured" population, but poor correlation between objective outcome measures, highlighting deficits in our understanding of PTLD.

The burden and determinants of post-TB lung disease.

BACKGROUND: Post-TB lung disease (PTLD) is an important but under-recognised chronic respiratory disease in high TB burden settings such as Tanzania.METHODS: This was a cross-sectional survey of adults within 2 years of completion of TB treatment in Kilimanjaro, Tanzania. Data were collected using questionnaires (symptoms and exposures), spirometry and chest radiographs to assess outcome measures, which were correlated with daily life exposures, including environment and diet.RESULTS: Of the 219 participants enrolled (mean age: 45 years ± 10; 193 88% males), 98 (45%) reported chronic respiratory symptoms; 46 (22%) had received treatment for TB two or more times; and HIV prevalence was 35 (16%). Spirometric abnormalities were observed in 146 (67%). Chest X-ray abnormalities occurred in 177 (86%). A diagnosis of PTLD was made in 200 (91%), and half had clinically relevant PTLD. The prevalence of mMRC ≥Grade 3 chronic bronchitis and dyspnoea was respectively 11% and 26%. Older age, multiple episodes of TB and poverty indicators were linked with clinically relevant PTLD.CONCLUSIONS: We found a substantial burden of PTLD in adults who had recently completed TB treatment in Tanzania. There is a pressing need to identify effective approaches for both the prevention and management of this disease.

Clinical standards for the assessment, management and rehabilitation of post-TB lung disease.

BACKGROUND: Increasing evidence suggests that post-TB lung disease (PTLD) causes significant morbidity and mortality. The aim of these clinical standards is to provide guidance on the assessment and management of PTLD and the implementation of pulmonary rehabilitation (PR).METHODS: A panel of global experts in the field of TB care and PR was identified; 62 participated in a Delphi process. A 5-point Likert scale was used to score the initial ideas for standards and after several rounds of revision the document was approved (with 100% agreement).RESULTS: Five clinical standards were defined: Standard 1, to assess patients at the end of TB treatment for PTLD (with adaptation for children and specific settings/situations); Standard 2, to identify patients with PTLD for PR; Standard 3, tailoring the PR programme to patient needs and the local setting; Standard 4, to evaluate the effectiveness of PR; and Standard 5, to conduct education and counselling. Standard 6 addresses public health aspects of PTLD and outcomes due to PR.CONCLUSION: This is the first consensus-based set of Clinical Standards for PTLD. Our aim is to improve patient care and quality of life by guiding clinicians, programme managers and public health officers in planning and implementing adequate measures to assess and manage PTLD.

Experimental hookworm infection: a randomized placebo-controlled trial in asthma.

BACKGROUND: Epidemiological studies suggest that hookworm infection protects against asthma, and therefore that hookworm infection may have a direct or an indirect therapeutic potential in this disease. We now report the first clinical trial of experimental hookworm infection in people with allergic asthma. OBJECTIVES: To determine the effects of experimental hookworm infection in asthma. METHODS: Thirty-two individuals with asthma and measurable airway responsiveness to adenosine monophosphate (AMP) were randomized and double blinded to cutaneous administration of either ten Necator americanus larvae, or histamine solution (placebo), and followed for 16 weeks. The primary outcome was the change in provocation dose of inhaled AMP required to reduce forced expiratory volume in 1 s by 20% (PD(20)AMP) from baseline to week 16. Secondary outcomes included change in several measures of asthma control and allergen skin sensitivity and the occurrence of adverse effects. RESULTS: Mean PD(20)AMP improved in both groups, more in the hookworm [1.49 doubling doses (DD)] than the placebo group (0.98 DD), but the difference between groups was not significant (0.51 DD; 95% confidence interval: -1.79 to 2.80; P=0.65). There were no significant differences between the two groups for other measures of asthma control or allergen skin sensitization. Infection was generally well tolerated. CONCLUSIONS: Experimental infection with ten hookworm larvae in asthma did not result in significant improvement in bronchial responsiveness or other measures of asthma control in this study. However, infection was well tolerated and resulted in a non-significant improvement in airway responsiveness, indicating that further studies that mimic more closely natural infection are feasible and should be undertaken.