Effects of omalizumab in severe asthmatics across ages: A real life Italian experience

BACKGROUND

This retrospective study aimed at evaluating long-term effects of Omalizumab in elderly asthmatics in a real-life setting.

METHODS

105 consecutive severe asthmatics (GINA step 4-5; mean FEV₁% predicted:66 ± 15.7) treated with Omalizumab for at least 1 year (treatment mean duration 35.1 ± 21.7 months) were divided into 3 groups according to their age at Omalizumab treatment onset: 18-39, 40-64 and ≥ 65 years.

RESULTS

Comorbidities, number of overweight/obese subjects and patients with late-onset asthma were more frequent among older people. A similar reduction of inhaled corticosteroids dosage and SABA on-demand therapy was observed in all groups during Omalizumab treatment; a similar FEV₁ increased was also observed. Asthma Control Test (ACT) improved significantly (p < 0.001) in the three groups, increasing from 15 [IQR:12-18] to 24 [IQR:22-25] in younger subjects, from 14 [IQR:10-16] to 21 [IQR:20-23] in the 40-64-year-group and from 15 [IQR:12-16] to 20 [IQR:18-22] in elderly patients where improvement was lower (p = 0.039) compared to younger people. Asthma exacerbations decreased significantly after Omalizumab but the percentage of exacerbation-free patients was higher in younger people (76.9%) compared to middle aged patients (49.2%) and the elderly (29%) (p = 0.049). After Omalizumab treatment, the risk for exacerbations was lower in subjects aged 40-64 (OR = 0.284 [CI95% = 0.098-0.826], p = 0.021) and 18-39 (OR = 0.133 [CI95% = 0.026-0.678], p = 0.015), compared to elderly asthmatics. Also, a significantly reduced ACT improvement (β = -1.070; p = 0.046) passing from each age class was observed.

CONCLUSION

Omalizumab improves all asthma outcomes independently of age, although the magnitude of the effects observed in the elderly seems to be lower than in the other age groups.

Allergy in urban elderly population living in Campania region (Southern Italy). A multicenter study

Given the increasing life expectancy observed in Western countries, there is a marked interest to know more about how aging could influence respiratory health. The aim of our study was to assess the prevalence, clinical characteristics and age of onset of allergic sensitization and clinical symptoms in a sample of atopic elders living in Campania region area (Southern Italy). Fourteen Allergy units or Centres examined a total of 462 patients. In this context 215 (46.53%) had positive skin prick tests (SPTs) to at least one allergen and were diagnosed with respiratory allergy. Parietaria represents the most common sensitizing agent in elders living in Campania region, followed by dust mites, grass pollen and Olea europaea. A relatively high percentage of atopic subjects suffered from respiratory symptoms at a fairly advanced age, namely 8.3% at 60-64 years, 10.2% at 65-70 and 5.7% at > 70 years. In conclusion, the prevalence and clinical significance of airway allergic sensitization in the elderly living in Campania region is more significant than expected in latter stages of life. Physicians should not neglect the role of atopy as a risk factor for the onset of allergic respiratory symptoms even in elderly patients.

Sensitization to cockroach allergens in the urban atopic populations living in Campania district (southern Italy). A multicenter study

BACKGROUND

Although cockroach (CR) is an important cause of allergic sensitization worldwide, only a few data are available in Italy and in a previous study we have observed, in Naples area, a low prevalence of CR sensitization.

OBJECTIVES

We sought to perform a prospective study for assessing the prevalence of allergic sensitization to CR in a sample of atopic population living in Campania district area (Southern Italy).

METHODS

Ten Allergy Units or Centres of Campania district participated in this cross-sectional study. Each centre was required to collect the results of at least 100 allergy consultations in consecutive outpatients referred for actual or suspected respiratory allergy. We registered demographic data, type and duration of respiratory symptoms, pets ownership, possible exposure to CR allergens, results of the skin prick tests (SPTs).

RESULTS

A total of 1477 patients were examined, 985 (66.68%) had a SPTs positivity to at least one allergen. In this context, ninety were sensitized to CR, thus the overall sensitization prevalence in subjects with respiratory allergy was 6.09% ranging between 0-11% and only five patients were mono-sensitized. Thirteen patients reported rhinitis (R) + bronchial asthma (A), twenty-one R + A + conjunctivitis (C), thirty-seven R + C, five only A and eleven individuals only R. Sixty-seven patients exhibited persistent and twenty-three intermittent symptoms. Dust mite constituted the first cause of associated sensitization to CR.

CONCLUSIONS

The prevalence of allergic sensitization to CR is not negligible in population living in Campania district and shows a higher trend in comparison to that found recently and some years ago in Naples area. Finally, we suggest atopic individuals and especially those highly sensitized to mite allergens or those living in low-income areas to be tested by SPTs / evaluation of serum specific IgE to CR allergens to exclude the occurrence of CR allergic sensitization.

Cypress pollen: an unexpected major sensitizing agent in different regions of Italy

OBJECTIVES

In this multicenter survey, we assessed the impact of sensitization to cypress in atopic patients in Italy and determined whether cypress pollen concentration changed over time.

METHODS

Allergists were required to collect the results of 100-200 consecutive skin prick tests (SPTs) performed during 2012. Seasonal symptoms were also recorded, as were airborne cypress pollen concentrations (data from the Italian Aerobiology Association) in 1998-2000 and 2010-2012.

RESULTS

We examined 2258 atopic outpatients (56% females; age, 2-84 years) sensitized to at least 1 of the aeroallergens tested (Dermatophagoides species, grass, pellitory, olive, cypress, birch, Alternaria tenuis, and dog and cat dander). We found that 62.9%, 16.1%, and 32.7% of patients living in central, northern, and southern Italy, respectively, were sensitized to cypress (P < .0001). The cypress pollen concentration peak was delayed from February to March in 1998-2000 and 2010-2012 in all 3 regions, with a shift in pollination towards spring. Patients who were monosensitized to cypress reported mainly rhinitis (90.7%-97.6%) and conjunctivitis (38.1%-100%). In polysensitized patients, the prevalence of rhinitis, conjunctivitis, and asthma increased progressively (P < .0001) from southern to northern Italy. The same trend was observed for the prevalence of reported winter symptoms typical of cypress allergy (28%-65%).

CONCLUSIONS

Today, cypress pollen is the most frequent sensitizing aeroallergen (assessed by SPT) in several areas of central Italy. Variations in the timing of the cypress pollination period may have favored this increased sensitization. Rhinitis and conjunctivitis are the predominant symptoms. The clinical impact of this allergy was poor in southern Italy and increased in central areas before reaching its peak in northern regions.

Perioperative anaphylactic risk score for risk-oriented premedication

Basing on the current knowledge, this paper is aimed to review the core characteristics of the most relevant therapeutic agents (steroids and antihistamines), administered to prevent perioperative anaphylaxis. Moreover, the Authors propose the validation of a Global Anaphylactic Risk Score, built up by recording the individual scores related to the most relevant anaphylaxis parameters (i.e. medical history, symptoms and medication for asthma, rhinitis and urticaria etc) and by adding them on all together; the score could be used in the preoperative phase to evaluate the global anaphylactic risk and to prescribe risk-oriented premedication protocols.

Results of the feasibility test of the Practical Approach to Lung Health in the Syrian Arab Republic

We assessed implementation of the Practical Approach to Lung Health (PAL) in primary care facilities in the Syrian Arab Republic and its short-term impact on respiratory care in patients aged 5+ years. After training on PAL for 76 general practitioners in 75 health centres, referrals and sputum smear examinations for patients increased. The mean number of drugs prescribed per patient decreased by 14.8% and that of antibiotics by 33.3%, while prescriptions for inhaled medications increased. The mean cost of drug prescriptions fell by 26.2%.

Development process of the Practical Approach to Lung Health in Kyrgyzstan

The Practical Approach to Lung Health (PAL) strategy was adopted by the Ministry of Health of Kyrgyzstan to improve the quality of case management of priority respiratory illnesses, including tuberculosis (TB). The process of development and implementation of the strategy is described in the present study. The World Health Organization stepwise framework was adapted and used to initiate the PAL strategy within the Kyrgyzstan primary health care (PHC) system. The process followed 10 steps which included the government decision to support PAL development, and the establishment of a national working group in charge of adapting guidelines, developing training materials and testing the feasibility and impact of the guidelines. On the basis of the test results, the guidelines and training materials were revised and a national PAL implementation plan was developed. The ongoing health sector reform which focuses, in priority, on strengthening PHC services and the assistance from the government of Finland, generated favourable political, technical and financial circumstances for the development and implementation of the PAL strategy.

Feasibility test results of the Practical Approach to Lung Health in Bishkek, Kyrgyzstan

SETTING

Ambulatory health centres in Bishkek, Kyrgyzstan.

OBJECTIVE

To assess the results of training family doctors in Practical Approach to Lung Health (PAL) techniques.

DESIGN

Comparison of the results of two surveys, before (baseline) and after (impact) training on PAL guidelines. Both surveys were carried out according to the same protocol.

RESULTS

A total of 86 family physicians working in three ambulatory health centres participated in both surveys. Respectively 893 and 992 respiratory patients were registered in the baseline and impact surveys. Baseline survey patients had longer duration of symptoms, were older and had more concomitant health conditions than impact survey patients. Findings suggest that PAL training has resulted in a decrease by one third in referrals to hospital or specialists or for diagnostic tests. Data do not show any improvement in tuberculosis case detection. However, in the impact survey, the number of drugs prescribed per patient decreased by 13.6% and the average cost of prescription of any drug per patient was reduced by 32.2%.

CONCLUSION

The study suggests that training in standardised PAL guidelines is likely to reduce referral as well as drug prescription costs for respiratory patients. These findings need to be confirmed by further studies.

The value of in vivo real time ultrasonography in assessing loin muscularity and carcass composition of rabbits

Sixty nine growing rabbits were scanned over the lumbar region using a real time ultrasonography (RTU) machine to estimate loin muscularity and carcass composition. Longissimus thoracis et lumborum muscle (LM) depth, width and area were taken. Animals were weighed (LW), slaughtered and carcass composition was determined. Equivalent measurements to those taken by RTU in vivo were taken on the carcass and muscularity indices were calculated on carcass and in vivo. Simple correlations between the two types of measurements were determined and carcass composition was estimated by simple and multiple regressions. The LW varied from 1200 to 3410g. The simple correlations between carcass and in vivo RTU LM measurements were high (P<0.001) and the LM area was the trait with the highest correlation (r=0.92). Simple correlations between muscularity indices measured by RTU and in carcass were significant (P<0.001). In vivo RTU measurements explained a large amount of the variation of the carcass meat weight (MW) and bone weight (r(2) range from 0.49 to 0.77; P<0.001). Using multiple regression equations to estimate carcass composition, the best fit was obtained with the LW and one or more in vivo RTU measurement. The LW explained 90.6% of the variation of MW in the carcass. In vivo RTU is able to estimate loin muscularity and carcass composition of rabbits with accuracy. The usefulness of in vivo RTU and LW to predict carcass composition of rabbits using multiple regressions was also shown.

Results of PAL feasibility test in primary health care facilities in four regions of Bolivia

SETTING

Primary health care (PHC) centres in four Bolivian regions.

OBJECTIVES

To test the feasibility and impact of training general practitioners (GPs) in standard case management of respiratory conditions in patients aged > or =5 years.

DESIGN

Comparison of the results of two surveys: the baseline survey before training and the impact survey after training on standard guidelines on case management of respiratory conditions.

RESULTS

A total of 78 GPs working in 65 health centres participated in both surveys. The baseline survey registered 1033 respiratory patients and the impact survey 1154. The patients were comparable in sex distribution, previous visits, duration of symptoms and clinical diagnoses. The differences were significant in age distribution, concomitant diseases and risk factors. As a result of training, referrals to a higher level decreased by 34.6% and the proportion of tuberculosis (TB) suspects identified increased by 30%. The number of drugs prescribed per patient decreased by 16.2%. The average cost of prescription of any drug per patient dropped by 32.3%.

CONCLUSION

Training in the standard practical approach to lung health guidelines improved the quality and reduced the cost of treatment of respiratory diseases at PHC units. Training should be an integral part of a comprehensive managerial approach for the implementation of case management guidelines.

Evolution of WHO policies for tuberculosis control, 1948-2001

We examine the evolution of WHO managerial policies for tuberculosis control during 1948-2001 to provide a new framework that will accelerate control expansion in the near future. In the first period (1948-63), a vertical approach to tuberculosis control was the policy adopted by WHO and the international community. However, although this approach was successful in more-developed countries, it largely failed in resource-poor settings. As a result, involvement of general health services was soon deemed essential. During 1989-98, a new framework for effective tuberculosis control was created and a new five-element strategy was branded with the name of DOTS. This period was characterised by the recognition of tuberculosis control as a public-health priority, the intensification of tuberculosis control efforts worldwide, and the return of tuberculosis to the political agenda of governments. However, although nominal adoption of DOTS increased rapidly due to massive promotion by WHO and partners, expansion to provide full access was too slow and only 23% of all infectious cases in 1999 were managed under DOTS. A truly multisectoral approach based on advocacy and social mobilisation, community involvement, and engagement of private-for-profit practitioners is becoming the way forward for tuberculosis control. HIV-associated tuberculosis and multidrug-resistant tuberculosis must be tackled as priority issues. We conclude that, based on the lessons of the past, the future of tuberculosis control should be focused on a pragmatic approach combining a specialised, well-defined management system with a fully integrated service delivery. A multisectoral approach that builds on global and national partnerships is the key to future tuberculosis control.

Case management of childhood pneumonia in developing countries: recent relevant research and current initiatives

Acute respiratory infections (ARI), mostly pneumonia, are one of the leading causes of death in young children in developing countries, accounting for 28% of childhood mortality. This paper provides a summary of the research and technical development efforts made in the last 15 years which contributed to improving the effectiveness of the case management strategy to reduce mortality from pneumonia in children in developing countries. Community intervention studies provided strong evidence that the strategy was feasible and effective in producing a substantial impact on pneumonia mortality. Clinical studies provided the rationale for improving the sensitivity and specificity of key signs of pneumonia, and for enhancing the therapeutic efficacy of standard home treatment. Research also provided data to deal with the problem of the clinical overlap of pneumonia and malaria in children. Technological initiatives succeeded in making appropriate diagnostic and therapeutic devices available. An important body of socio-cultural knowledge about family practices regarding pneumonia and ARI in children was built up and provided orientation on effective communication between health workers and families about home care of children with ARI. Health systems research focused on methods for surveillance of bacterial drug resistance and methodologies for evaluating the control programmes. Despite advances in the development of vaccines against respiratory bacteria and in the prevention of risk factors for pneumonia in children, case management will continue to be a central strategy for preventing mortality. Current international research initiatives are looking into measures that can improve the referral of severe pneumonia and effective management of severe pneumonia at first level hospitals.

Evolution of the concepts of functional anatomy of the knee joint

It is the purpose of this study to present a review of studies on the kinematics of the knee joint and load distribution in the two compartments, medial and lateral, in order to reveal the evolution of concepts of functional anatomy. Flexion-extension features have been clearly defined by numerous authors who have used different methods of research. Transverse rotation, instead, still needs to be clarified. In particular, whether or not a screw-home movement exists has been questioned by many authors who have studied the kinematics of the knee, both without loading and during walking. Dynamic studies have shown how the radiographic method (static) to deduce load distribution in the knee joint is inadequate; this is because during walking, loading tends to be transmitted on the medial compartment, also the case in valgus knees.

A national programme for the control of acute respiratory infections

In 1989 Egypt set up a programme to combat acute respiratory infections among children aged under 5 years. The present article indicates what has been achieved and the lessons that have been learnt.

National tuberculosis programme review: experience over the period 1990-95

Since 1990 the WHO Global Tuberculosis Programme (GTB) has promoted the revision of national tuberculosis programmes to strengthen the focus on directly observed treatment, short-course (DOTS) and close monitoring of treatment outcomes. GTB has encouraged in-depth evaluation of activities through a comprehensive programme review. Over the period 1990-95, WHO supported 12 such programme reviews. The criteria for selection were as follows: large population (Bangladesh, Brazil, China, Ethiopia, India, Indonesia, Mexico, and Thailand); good prospects of developing a model programme for a region (Nepal, Zimbabwe); or at advanced stage of implementation of a model programme for a region (Guinea, Peru). The estimated combined incidence of smear-positive pulmonary tuberculosis was 82 per 100,000 population, about 43% of the global incidence. The prevalence of infection with human immunodeficiency virus (HIV) was variable, being very high in Ethiopia and Zimbabwe, but negligible in Bangladesh, China, Nepal and Peru. The programme reviews were conducted by teams of 15-35 experts representing a wide range of national and external institutions. After a 2-3-month preparatory period, the conduct of the review usually lasted 2-3 weeks, including a first phase of meetings with authorities and review of documents, a second phase for field visits, and a third phase of discussion of findings and recommendations. The main lessons learned from the programme reviews were as follows: programme review is a useful tool to secure government commitment, reorient the tuberculosis control policies and replan the activities on solid grounds; the involvement of public health and academic institutions, cooperating agencies, and nongovernmental organizations secured a broad support to the new policies; programme success is linked to a centralized direction which supports a decentralized implementation through the primary health care services; monitoring and evaluation of case management functions well if it is based on the right classification of cases and quarterly reports on cohorts of patients; a comprehensive programme review should include teaching about tuberculosis in medical, nursing, and laboratory workers' schools; good quality diagnosis and treatment are the essential requirements for expanding a programme beyond the pilot testing; and control targets cannot be achieved if private and social security patients are left outside the programme scope. The methodology of comprehensive programme review should be recommended to all countries which require programme reorientation; it is also appropriate for carrying out evaluations at 4-5-year intervals in countries that are implementing the correct tuberculosis control policies.

The statics of cervical traction

The statics of a sliding body was used to study the distribution of forces during the application of cervical traction in supine patients. This theoretical analysis was completed using a dynamometer to determine the static friction between bed surface and patient head. Therefore, we measured the head weight in 12 inpatients and the minimum force that causes impending motion of the head on the bed surface. The static friction coefficient was calculated from the ratio of the two quantities. The forces acting on the cervical spine were determined by inserting the former data into a specifically designed algorithm that forecasted a progressively increasing traction angle. The coefficient of static friction was 0.62, whereas the maximum available force acting on the cervical spine was obtained with a 35 degrees traction inclination. In contrast, the forces dissipated by the plane progressively decreased with larger angles.

Pathogenesis of uncus deformation and vertebral artery compression: histologic investigations of the uncus and dynamic angiography of the vertebral artery in the cadaveric cervical spine

Twenty-one cervical spines were collected from fresh cadavers (12 male, nine female), their ages ranging from 10 to 90 years (mean 49.47). After removing muscle debris from the spines, they were mounted and tested on a device to passively reproduce the main movements of the spine. The degree of motion in flexion-extension and lateral bending significantly decreased from group A (ages 10-49 years) to group B (51-90 years) (p < 0.005) and was directly correlated with the amount of cervical spine degenerative alterations. The incidence of these alterations, classified according to Lysell (1969), was highest at C5-6. On the testing machine, dynamic angiography of the vertebral artery showed an impingement with extrinsic compression of the vessels in four of 28 successful injections. The histologic serial sections of the uncus showed a characteristic pattern of ossification-deformation: a newly formed cartilaginous tissue tipping the apex of the uncus, forming a double protruding contour of the apex, rapidly ossifying, and appearing to deform outward together with the disk degeneration and consequently decreasing in height.

Risk factors for deaths in children under 5 years old in Bagamoyo district, Tanzania

We conducted a population based case control study of deaths in children < 5 years old from Bagamoyo District, Tanzania, to evaluate factors associated with death, and factors associated with not utilizing Government health care system. Six hundred and ten children who died between 1 July, 1986 and 30 June 1987 were enrolled as cases; 1,160 healthy control children were selected by multistage random cluster sampling. Twenty-five percent of deaths were ascribed to pneumonia based on "verbal autopsy"; 39% of acute respiratory deaths occurred in children < 6 months of age. In a multivariate analysis, significant independent associations were found with mother as sole decision maker for treatment (O.R = 0.13; 95% C:I. 0.07, 0.22); use of water from village well, pond, or river vs. tap water (O.R. = 11.86; 95% C.I., 5.46, 25.72); the child eating with others (O.R. = 9.42; 95% C.I. 5.68, 15.62) and the child sleeping in the room where cooking is done (O.R. = 2.78; 95% C.I. 1.79, 4.33). Overall only 45% of families utilized Government health care (village health worker, dispensary or health centre) during their child's terminal illness. Families utilizing Government health care were significantly more likely to say that the mother alone could make treatment decision (O.R. = 2.49, 95% C.I. 1.39, 4.46), and to be closer to a dispensary. The main reasons for not utilizing Government health care were 'traditional medicine is better' (41%) and 'no drugs available' (38%).

Experimental osteoporosis in the rat induced by a hypocalcic diet

The administration of a diet deficient in calcium in the rat quickly produces a reduction in the skeletal mass, with narrowing of the diaphyseal cortex, and less density of the metaphysis. The bone mineral content, determined by a double ray photonic mineralometer, is significantly lower as compared to controls, while histological examination does not reveal defects in calcification. The pathogenetic mechanism is characterised by stimulation of the parathyroid glands in response to a decrease in plasma calcium determined by the insufficient diet. We observed a bone response in two phases: the first, with elevated velocity of remodelling and prevalence of osteoclastic resorption despite the presence of intense osteoblastic activity; the second, with reduced bone remodelling (except for the metaphyseal area). Although these observations do not imply that human osteoporosis involves the same pathogenetic mechanism, it appears possible to use this experimental model to study the effects of endocrine and pharmacological factors on the activity of bone remodelling, which also in human osteoporosis is characterised by the prevalence of osteoclastic resorption.

Indoor air pollution in a Kenyan village

In April 1986, a study was carried out within rural households in Maragua area, Muranga District, Republic of Kenya, to assess the degree of indoor air pollution and to find its relationship, if any, to acute respiratory infections (ARI) among children aged below 5 years within the study. This study was carried out within an ongoing aetiological and epidemiological community study on ARI as a collaborative effort between the Department of Paediatrics, University of Nairobi; the Department of Chemistry, Kenyatta University; the Department of Environmental Sciences, Agricultural University, Wagenigen, The Netherlands; the World Health Organization; and the Ministry of Health, Republic of Kenya. Repeated 24 hour measurements of respirable suspended particles (RSP) and nitrogen dioxide (NO2), were carried out in 36 randomly selected houses where most of the cooking was done on open fires using firewood and crop residues as fuel. Data on house characteristics and activity in the study were gathered by questionnaire. The mean of 24 hour average RSP concentration (1400mg/m3), average during the 7 hours of daily burning (3000-4000mg/m3), and evening peak levels (up to 3600mg/m3) indicate that deleterious health effects due to exposure to excessive levels of toxic pollutants in smoke from biomass combustion are likely to occur especially among pre-school children and women. Concentrations of selected polycyclic hydrocarbons in the particulate material were found to be high. It was not possible to demonstrate a relationship between the indoor air pollution and episodes of ARI partly because of small sample size and also the more or less homogeneous nature of pollution among all the households.

Impact of present control methods on the problem of tuberculosis

In spite of the considerable efforts that have been made to control tuberculosis in developing countries in the last three decades, the decline in the global epidemiologic problem has been slow. It is now realized that the possibility of rapidly influencing the tuberculosis problem in these countries with the present control technologies has been overestimated. It is clear that bacille Calmette-Guérin (BCG) vaccination, even in places where a high efficacy was demonstrated, does not substantially influence the chain of transmission. Case management, including bacteriologic diagnosis and chemotherapy, is a complex technology. Although it is potentially effective for the reduction of mortality and the risk of infection, there are many difficulties for its efficient application in developing countries. Although there should be no hesitation in the application and full utilization of what is already known, a major thrust in research may generate ways of accelerating the control of tuberculosis in developing countries. Without new developments in technology for tuberculosis control, the goal of worldwide control has still a long way to go.

Musculoskeletal demands on flamenco dancers: a clinical and biomechanical study

The flamenco dancer acts on the floor like a drummer. The percussive footwork and vibration patterns created during dancing impose unusual demands on the musculoskeletal system. This study investigated the clinical and biomechanical aspects of this task. Using the electrodynogram and skin-mounted accelerometers, foot pressures as well as hip and knee vibrations were recorded in 10 female dancers after a thorough clinical evaluation. A health questionnaire was also distributed to 29 dancers. Foot pressures and acceleration data reveal the percussive nature of the dance. Some clinical findings, like calluses, are related to pressure distribution. Urogenital disorders, as well as back and neck pain, may be related to the vibrations generated by the flamenco dance form. The hip joint seems to absorb most of the impacts. "Vibration-pressure" diagrams are suggested as a useful tool for evaluating a dancer's biomechanical behavior, as well as the effect of floors and footwear on this behavior.

Epidemiology of tuberculosis

Author refers some data about prevalence and incidence of infection and morbidity in tubercular disease. These data are very discordant according to different social conditions of countries in which they are been derived. Particularly, he analyses the importance of an extended tuberculin survey, as the essential method to study both epidemiological parameters. In this paper, Author emphasizes how the test needs to be used systematically and in subjects of the same age. At last, mortality is more an indicator of the efficiency of the case finding and treatment programme than an epidemiological index. Indeed there is a parallel increase in the proportions of deaths of patients older than 45 years of age also in under-developing countries.

The future of the fight against tuberculosis in the world

In spite of extraordinary improvement of the methods of prophylaxis, casefinding and treatment, tuberculosis situation throughout the world is further on very serious. In developing countries comprising a high proportion of the world population scarce or only very slow progress may be noted. 4 to 5 millions of highly infectious new cases of tuberculosis and in all 10 millions of new cases of tuberculosis are estimated every year in the world. A great part of the population concerned is living under conditions of poverty, malnutrition, and disease. In these countries tuberculosis control programmes may be actually feasible from medical and technological points of view but they are without any prospects for success by epidemiological, social, and economic reasons. In developing countries the development of a comprehensive primary health care system according to the recommendations of the Alma-Ata Conference has priority in public health policies. The control of tuberculosis is adequate to develop within this system.

Pathogenesis of tuberculosis and effectiveness of BCG vaccination

Among the hypotheses offered to explain the conflicting results of various trials of BCG vaccination, the one invoking gross differences in the immunogenic properties of the various BCG vaccines (strains) has received most attention. Indeed, for many years research in BCG vaccination has been directed almost entirely towards improving the quality of vaccines. the anticipated benefit of this work, however, is not borne out by the results of the latest trial in India. Whereas it cannot be excluded that technological advances may have resulted in the worst vaccines ever, it also remains possible that the basic hypothesis was less relevant than presumed. the quality of the vaccine may be of little importance and a different explanation should be sought for the observed differences in protection. One possible lead is the observation that BCG vaccination consistently appeared to be of poor efficacy under conditions where, in a vaccination programme, even an effective vaccine would have little impact on the tuberculosis problem, i.e. where the majority of cases originated from the population already infected. The hypothesis offered is that in such populations the pathogenesis of tuberculosis is different from that prevailing under the clearly exceptional conditions under which BCG vaccination was effective. Rather than being the direct result of primary infection, tuberculous disease (observed) may be the result of reinfection. In this case BCG vaccination cannot be expected to have a protective effect.