scholarly journals EPIDEMIOLOGICAL STUDIES ON RESPIRATORY INFECTIONS OF THE RABBIT

1927 ◽  
Vol 45 (3) ◽  
pp. 553-560 ◽  
Author(s):  
David T. Smith

These observations have brought out three facts which may be stated briefly as follows. 1. An acute respiratory epidemic was incited by mucoid strains of Bact. lepisepticum of moderate and uniform virulence. 2. The epidemic was brought about not by an alteration in the virulence of the prevailing strains of Bact. lepisepticum but by a sudden distribution of virulent organisms among a susceptible population hitherto unexposed. 3. Individuals in this population showed different degrees of resistance to the infecting bacillus; some died from pneumonia and septicemia, while others localized the infection to the nasal passages. The significance of these facts has been discussed at length elsewhere (4).

Author(s):  
Daniel B. Odo ◽  
Ian A. Yang ◽  
Luke D. Knibbs

The domestic combustion of polluting fuels is associated with an estimated 3 million premature deaths each year and contributes to climate change. In many low- and middle-income countries (LMICs), valid and representative estimates of people exposed to household air pollution (HAP) are scarce. The Demographic and Health Survey (DHS) is an important and consistent source of data on household fuel use for cooking and has facilitated studies of health effects. However, the body of research based on DHS data has not been systematically identified, nor its strengths and limitations critically assessed as a whole. We aimed to systematically review epidemiological studies using DHS data that considered cooking fuel type as the main exposure, including the assessment of the extent and key drivers of bias. Following PRISMA guidelines, we searched PubMed, Web of Science, Scopus and the DHS publication portal. We assessed the quality and risk of bias (RoB) of studies using a novel tool. Of 2748 records remaining after removing duplicates, 63 were read in full. A total of 45 out of 63 studies were included in our review, spanning 11 different health outcomes and representing 50 unique analyses. In total, 41 of 45 (91%) studies analysed health outcomes in children <5 years of age, including respiratory infections (n = 17), death (all-cause) (n = 14), low birthweight (n = 5), stunting and anaemia (n = 5). Inconsistencies were observed between studies in how cooking fuels were classified into relatively high- and low-polluting. Overall, 36/50 (80%) studies reported statistically significant adverse associations between polluting fuels and health outcomes. In total, 18/50 (36%) of the analyses were scored as having moderate RoB, while 16/50 (32%) analyses were scored as having serious or critical RoB. Although HAP exposure assessment is not the main focus of the DHS, it is the main, often only, source of information in many LMICs. An appreciable proportion of studies using it to analyse the association between cooking fuel use and health have potential for high RoB, mostly related to confounder control, exposure assessment and misclassification, and outcome ascertainment. Based on our findings, we provide some suggestions for ways in which revising the information collected by the DHS could make it even more amenable to studies of household fuel use and health, and reduce the RoB, without being onerous to collect and analyse.


Vestnik ◽  
2021 ◽  
pp. 280-284
Author(s):  
Х. Б. Сарсенбай ◽  
А. Н. Турсынханова ◽  
Б. А. Конысов

Согласно данным ВОЗ, современные эпидемиологические исследования показали, что рецидивирующие респираторные инфекции у детей раннего и дошкольного возраста сохраняются на высоком уровне 10-50% в течение более 40 лет. Конец вакцинации может спровоцировать массовые инфекционные заболевания. Врачи бьют тревогу, что число отказников от обязательной вакцинации растет. Только в каждой поликлинике Алматы 30-40 родителей в год говорят о готовности к профилактике заболеваний. Среди тех, кто категорически отказывается трогать своих детей иголками, - те, кто идет по пути религии. Они считают, что прививка противоречит убеждениям. В последнее время список недовольных групп пополняют и простые жители, которые скептически относятся к квалификации белых. According to WHO, current epidemiological studies have shown that recurrent respiratory infections in young children and preschool children persist at a high level of 10-50% for more than 40 years. The end of vaccination can provoke mass infectious diseases. Doctors are sounding the alarm that the number of refusers from mandatory vaccination is growing. Only in every polyclinic in Almaty, 30-40 parents a year talk about their readiness for disease prevention. Among those who categorically refuse to touch their children with needles are those who follow the path of religion. They believe that vaccination is contrary to their beliefs. Recently, the list of discontented groups has been supplemented by ordinary residents who are skeptical about the qualifications of whites.


1926 ◽  
Vol 43 (4) ◽  
pp. 573-588 ◽  
Author(s):  
Leslie T. Webster

Rabbits with no previous exposure to Bact. lepisepticum were given, intranasally, a known dose of one strain or another of this organism, or of B. bronchisepticus. The results give grounds for the following conclusions.


1926 ◽  
Vol 43 (4) ◽  
pp. 555-572 ◽  
Author(s):  
Leslie T. Webster

1. Four general types of spontaneous pneumonia, associated with strains of Bact. lepisepticum similar in biology and virulence, are described: (1) an acute, diffuse form, with subpleural and perivascular orientation of the exudate, (2) lobar, (3) pleuro-, and (4) abscess pneumonia. 2. The acute, diffuse, lobar, and pleuro pneumonias may be induced experimentally by intranasal instillation of a virulent strain of Bact. lepisepticum. 3. These same types occur when the organisms are inoculated intravenously, intratesticularly, and subcutaneously. 4. Intrabronchial insufflation of the organisms brings about infection in less than half of the animals. When effective, a sharply circumscribed, peribronchial lesion is found at the base of the lung, which spreads peripherally by direct extension, and generally by invasion of the blood stream. 5. It is concluded that differences in the types of pneumonia following infection with similar strains of Bact. lepisepticum depend upon the resistance of the animal, and that the usual portal of entry of this organism into the lungs, in cases of acute and lobar pneumonia, is by way of the blood stream.


2021 ◽  
Vol 20 (2) ◽  
pp. 296-300
Author(s):  
Francisco Patricio De Andrade Júnior ◽  
Januse Míllia Dantas de Araújo ◽  
Laisa Vilar Vilar Cordeiro ◽  
Egberto Santos Santos Carmo ◽  
Vanessa Santos de Arruda Barbosa ◽  
...  

Introduction: tuberculosis is a bacteriosis caused by the etiological agent Mycobacterium tuberculosis, which initially affects the lungs, however it can become extrapulmonary. Although this infection is an important public health problem in Brazil, epidemiological studies on this disease are scarce. Objective: thus, the present study aimed to elucidate the epidemiological profile of people affected by tuberculosis in Campina Grande – PB, between the years 2014 to 2018. Methodology: this is an epidemiological, retrospective, analytical and documentary study, in which data were collected from the Department of Informatics of the “Sistema Único de Saúde”. Results: Between 2014 and 2018, 795 cases of tuberculosis were reported in Campina Grande-PB, with 2018 having the highest number of cases (24.6%). The epidemiological profile of those affected was predominantly male, aged 20 to 39 years, with low schooling, mixed race and residents of the urban area. When associating sex with immunosuppressive factors, a statistically significant association was observed between, HIV, the state of acquired immunodeficiency syndrome (AIDS) and alcoholism (p <0.05). Conclusion: in this way, the data of this research can guide the development of indicators and public policiesfor the most susceptible population.


2020 ◽  
Vol 8 (9) ◽  
pp. 1280
Author(s):  
Naganori Nao ◽  
Miwako Saikusa ◽  
Ko Sato ◽  
Tsuyoshi Sekizuka ◽  
Shuzo Usuku ◽  
...  

Human metapneumovirus (HMPV) is a major etiological agent of acute respiratory infections in humans. HMPV has been circulating worldwide for more than six decades and is currently divided into five agreed-upon subtypes: A1, A2a, A2b, B1, and B2. Recently, the novel HMPV subtypes A2c, A2b1, and A2b2 have been proposed. However, the phylogenetic and evolutionary relationships between these recently proposed HMPV subtypes are unclear. Here, we report a genome-wide phylogenetic and evolutionary analysis of 161 HMPV strains, including unique HMPV subtype A2b strains with a 180- or 111-nucleotide duplication in the G gene (nt-dup). Our data demonstrate that the HMPV A2b subtype contains two distinct subtypes, A2b1 and A2b2, and that the HMPV subtypes A2c and A2b2 may be different names for the same subtype. HMPV A2b strains with a nt-dup also belong to subtype A2b2. Molecular evolutionary analyses indicate that subtypes A2b1 and A2b2 diverged from subtype A2b around a decade after the subtype A2 was divided into the subtypes A2a and A2b. These data support the A2b1 and A2b2 subtypes proposed in 2012 and are essential for the unified classification of HMPV subtype A2 strains, which is important for future HMPV surveillance and epidemiological studies.


PEDIATRICS ◽  
1992 ◽  
Vol 89 (5) ◽  
pp. 855-859
Author(s):  
Karin Helweg-Larsen ◽  
Lisbeth B. Knudsen ◽  
Markil Gregersen ◽  
Jørn Simonsen

To investigate a reported increase, from 0.4 to 1.3 per thousand live births, in the Danish incidence of sudden infant death syndrome (SIDS), a retrospective analysis of SIDS in Denmark from 1972 to 1983 was carried out. Based on data registered with the National Board of Health, a notable regional difference in SIDS rate between the western and eastern parts of Denmark was found. This difference did not correlate with the overall postneonatal mortality by region. Danish law requires medicolegal investigation in all cases of sudden unexpected death. Medicolegal autopsies are performed only in the three forensic institutes which cover all of Denmark. Despite the law and a uniform organization of the forensic medical services, differing application of postmortem examinations and individual interpretation of the history and autopsy in cases of sudden infant death existed. Differences in reporting of respiratory infections, suffocation, and cardiac malformation were found to contribute to the increase and to regional disparities in SIDS incidence. The three Danish forensic institutes examined all cases of sudden infant deaths in Denmark 1987 and 1988. These cases were classified as explained cause of death, pure SIDS, and atypical SIDS; atypical cases were evaluated by consensus. The SIDS incidence (the number of classic SIDS and atypical SIDS per thousand live births) was 1.9 in 1987 and 1.3 in 1988, and it was identical in the eastern and western part of Denmark; however, a higher incidence both of overall postneonatal and SIDS mortality was found in the middle region of Denmark. The analysis stresses the importance of high autopsy rate and expert investigation in all cases of infant death in order to obtain reliable data for epidemiological studies. A prospective joint study of all postneonatal infant deaths in Finland, Iceland, Norway, Sweden, and Denmark will be carried out to analyze the reliability and the possible cause of reported differences in SIDS incidence in the five Nordic countries.


2020 ◽  
Author(s):  
Sujit Kumar Nath

We model the propagation of an infection, in a population, as a simplified age-dependent branching process. We analytically estimate the fraction of population, needed to be infected or immuned, to achieve herd immunity for an infection. We calculate this estimation as a function of the incubation period of the contagion, contact probability among the infected and susceptible population, and the probability of disease transmission from an infected to a susceptible individual. We show how herd immunity is strongly dependent on the incubation period, and it may be extremely difficult to achieve herd immunity in case of large incubation period. We derive the distribution of generation time from basic principles, which, by far, has been assumed in an ad hoc manner in epidemiological studies. We quantify the success probability of quarantine measures before achieving herd immunity, and discuss a novel method for designing effective quarantine measures in the absence of any pharmaceutical interventions. We also compare the effectiveness of an early imposition against a delayed imposition of lockdown, of the same duration, in mitigating infection from a population.


2020 ◽  
pp. 1-4
Author(s):  
Jagdish Chaturvedi ◽  
Pooja Kadambi

The COVID-19 pandemic has been responsible for over 500,000 deaths and 12 million infections as of July 2020. Though the number of cases in India is growing, the rate of rise rising in infections and the relative mortality rate has been lower than predicted. While many hypotheses have been laid out as possible reasons, a few physicians noticed a significant peak in COVID19-like respiratory infections through November – January 2020, and. They attributed this as the reason behind the lower mortality rate as a result of some kind of pre-existing immunity to the virus. A social media survey instrument was used to gather inputs from doctors and other individuals in the healthcare industry to understand the volume of doctors who noticed rising COVID19-like viral URTI cases during November – January 2020. The survey specifically asked about symptoms associated with coronavirus infections and about any rise in cases noted by treating physicians. 174 individuals answered the survey (46% treating physicians and 54% other healthcare professionals). The survey covered 41 cities in India and reported a growth of cases from before November 2019 to a peak in January 2020. Physicians surveyed, reported a rise in upper respiratory cases up to 50% during that time. 91% of all individuals surveyed had some or all of the symptoms associated with coronavirus infection. These findings may indicate the presence of an earlier strain of coronavirus or similar virus and be a contributing factor to the slower initial spread and lowered mortality noted in India. Further epidemiological studies are needed to draw any definitive conclusions.


Author(s):  
Rafael Junqueira Buralli ◽  
Amana Freitas Dultra ◽  
Helena Ribeiro

Pesticide exposure may affect children’s respiratory and allergic health, although results from epidemiological studies have not reached consensus. This review aims to analyze the scientific evidence on respiratory and allergic effects of exposure to agricultural pesticides in children aged up to 12 years old. The databases PubMed, Web of Science, Scielo, and Lilacs were screened to select articles published in English, Spanish, or Portuguese, and 21 articles were included in this review. Most investigations were conducted in North America (mostly in the United States), while no studies conducted in Latin America or Africa were found, despite their intensive use of pesticides. Children are exposed to pesticides through multiple pathways from the prenatal period throughout later developmental stages and may experience several respiratory effects. Most studies (79%) found positive associations with pesticide exposure and children’s respiratory and allergic effects such as asthma, wheezing, coughs, acute respiratory infections, hay fever, rhinitis, eczema, chronic phlegm, and lung function impairments. Contrastingly, 21% of the studies found no associations between pesticide exposure and children’s respiratory health. The vast differences among the characteristics of the studies hamper any comparison of the results. Exposure to pesticides may have several impacts on childhood respiratory health. More studies must be conducted, especially in low- and middle-income countries, preferably with comparable research protocols adapted to local realities. Efforts should be made to develop comprehensive risk mitigation strategies and behavioral interventions to reduce children’s exposure to pesticides used in agriculture and respiratory health effects, and to ensure healthy childhood growth.


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