Inhalation Of Infected Droplets Research Articles

Prevalence and Retrospective Insight on Tuberculosis in Human Patients in Cross River State, Nigeria; One Health Approach to its Control.

Tuberculosis (TB) is a major zoonotic disease of public health importance worldwide. Its burden is more in developing countries due to inadequate surveillance, co-infection with HIV/AIDS and poor social amenities; hence consumption of unpasteurized milk, contaminated meat and inhalation of infected droplets from animals or patients with active TB are the major risk practices. A survey was conducted on TB prevalence from 2013 to 2014 while patients records from TB and Leprosy units of hospitals in the three Agricultural zones (Ogoja, Ikom and Calabar) of Cross River State, Nigeria were assessed from 2000 to 2010. Out of 1,170 sampled patients, 8 (0.7%) were positive, of which 6 and 2 isolates were identified as M. tuberculosis and M. bovis, respectively. Out of 52,558 studied patients files, 235 (0.4%) were positive with varied annual prevalence; the highest (1.0%) and lowest (0.2%) in 2009 and 2011, respectively. The prevalence was higher in dry (0.9% and 0.5%) than the rainy season (0.5% and 0.4%), in females (0.9% and 0.5%) than the males (0.4% and 0.4%) in the survey and retrospective studies, respectively. The age distribution of TB among the patients were; (0% and 0.3%), (0.4% and 0.4%), (0.7% and 0.4%) and (1.5% and 0.7%) for those (≤ 18), (19-40), (41-60) and (> 60) yrs old in the survey and retrospective study, respectively. TB is prevalent in human patients in Cross River State hence, the need for sustainable campaign, continuous surveillance and private/ public health partnership in accurate and early diagnosis, treatment and one health approach to its control.

Influence of environmental factors on the spread of COVID-19 in Saudi Arabia.

BackgroundCoronavirus disease 2019 (COVID-19) has affected millions of people worldwide. The infection is mostly spread through the inhalation of infected droplets. Saudi Arabia is a vast country having different climatic conditions.MethodsThe study evaluated the influence of environmental factors on the spread of COVID-19. Six zones (A to F) were classified depending on the climatic conditions. The study was conducted by retrospective analysis of COVID-19 records from the ministry of health between the months of September 2020 and August 2021. The environmental data such as average temperature (°C), humidity (%), wind speed (m/s) and sun exposure (kwh/m2) were retrieved from official sites. The data was analyzed to determine the effect of these factors on the spread of COVID-19. SPSS IBM 25 software was used to conduct the analysis and p < 0.05 was considered to indicate the significance of the results.ResultsAccording to the findings, the rate of infection was greater between April and July 2021. Six climatic zones experienced high temperatures, little humidity, consistent wind flow, and intense sun exposure throughout this time. The correlation study revealed a significant (p < 0.05) relationship between the environmental factors and the spread of COVID-19. The data suggested that during summer condition when the weather is hot, less humid, and steady wind flow with lots of sun exposure, the COVID-19 infection rate got augmented in Saudi Arabia. Poor ventilation and closed-door habitats in an air-conditioned atmosphere during this period could have played a role in human transmission. More research on air quality, population mobility and diseased condition is essential, so that precise proactive measures can be designed to limit the spread of infection in specific climatic seasons.

Predictors of COVID-19 among Healthcare Workers who were Exposed to COVID-19

SARS-CoV-2 is transmitted via the inhalation of infected droplets or through direct contact with contaminated surfaces. Aerosol-generating procedures can also lead to airborne transmission. Healthcare workers (HCWs) are at higher risks for infections than the general (...)

Prevention of 21st Century Emerging Pandemics, Covid-19: Using Face Masks

Background: Emerging infections that are airborne or droplets infections, spread by inhalation or cotact with infected ‘Aerosols' or droplets. COVID-19 and TB are examples of infectious pathogens that are transmitted by inhalation of infected droplets or air. All human beings are at risk of breathing in infectious microbes in the air. Despite this fact and the negative impacts caused by infectious diseases, much attention is still not given to the use of face masks; as they were not recommended for preventing airborne/droplets infections in previous epidemics or pandemics. It was during the emergence of SARS in 2003 that droplets infections and the use of face masks were taken seriously by authorities, but most people are still reluctant to use them. The SARS outbreak was followed by Human swine influenza (H1N1) in 2009, also from zoonotic origin. Face masks were then found to be helpful in the prevention of epidemics/pandemics that can spread through airborne or droplets infections, during and after these two outbreaks. However, face masks have never been given any serious attention by the public, just like now; as some people still refuse to wear them despite warning that COVID-19 can be transmitted through infected droplets. From this project's objectives, we would be able to know whether people are complying with the wearing of masks or not. We will also know the weaknesses or strengths of wearing them, and give professional recommendations. Aside these the study will also benefit everyone, especially the vulnerable group in the COVID-19 Pandemic's transmission, like pregnant women. It will draw the attention of health workers, especially midwives, the pregnant women, the community and family heads to the prevention of stillbirth or preterm delivery due to COVID-19. This project's findings will serve as a guide to Regional, Metropolitan, Municipal, and District Health Directorates in their Every Newborn Action Plan (ENAP) strategy to curb stillbirth rate, especially soaring in the Tema metropolis. It may also serve as a source of reference for future researchers who would take up similar studies.Aim: To assess people compliance to the wearing of face masks and find out the strengths or weaknesses associated with it and give recommendations.Methodology: A checklist will be used to observe how two thousand, seven hundred (2,700) people (above 18 years who are not incapacitated) are wearing face/nose masks. This will be started after approval. Then, questionnaires will be given out to one thousand, three hundred and fifty (1,350) consented individuals (health workers, patients and the general public) who are above eighteen (18) years to answer. Published and grey literatures will be reviewed using related online publications from any year that is related to this project. Three strategical search approaches will be used to search for literature: data from health and social issues would be reviewed, custom Google seacrhes; then experts would be consulted for validation of results. Hypothesis: Some people are not wearing face/nose masks; others wear them wrongly.Expected Outcome: Our expectations are that the project would reveal whether people are complying the directive from experts and national presidents to wear face masks. Findings of this projects are expected to reveal the strengths or weaknesses associated with the wearing of face masks and give professional recommendations. The project is an emergency one started in April, 2020 and will end in October, 2020. Findings of the projects are expected to be submitted in October or November, 2020.

Susceptibility of Midge and Mosquito Vectors to SARS-CoV-2.

SARS-CoV-2 is a recently emerged, highly contagious virus and the cause of the current COVID-19 pandemic. It is a zoonotic virus, although its animal origin is not clear yet. Person-to-person transmission occurs by inhalation of infected droplets and aerosols, or by direct contact with contaminated fomites. Arthropods transmit numerous viral, parasitic, and bacterial diseases; however, the potential role of arthropods in SARS-CoV-2 transmission is not fully understood. Thus far, a few studies have demonstrated that SARS-CoV-2 replication is not supported in cells from certain insect species nor in certain species of mosquitoes after intrathoracic inoculation. In this study, we expanded the work of SARS-CoV-2 susceptibility to biting insects after ingesting a SARS-CoV-2-infected bloodmeal. Species tested included Culicoides sonorensis (Wirth & Jones) (Diptera: Ceratopogonidae) biting midges, as well as Culex tarsalis (Coquillett) and Culex quinquefasciatus (Say) mosquitoes (Diptera: Culicidae), all known biological vectors for numerous RNA viruses. Arthropods were allowed to feed on SARS-CoV-2-spiked blood and at a time point postinfection analyzed for the presence of viral RNA and infectious virus. Additionally, cell lines derived from C. sonorensis (W8a), Aedes aegypti (Linnaeus) (Diptera: Culicidae) (C6/36), Cx. quinquefasciatus (HSU), and Cx. tarsalis (CxTrR2) were tested for SARS-CoV-2 susceptibility. Our results indicate that none of the biting insects, nor the insect cell lines evaluated support SARS-CoV-2 replication, suggesting that these species are unable to be biological vectors of SARS-CoV-2.

COVID-19: OUTBREAK, TRANSMISSION, DIAGNOSIS, POTENTIAL TREATMENT AND SITUATION IN PAKISTAN

The Coronavirus disease 2019 (COVID-19) that originated in Wuhan, China in December 2019 has become a pandemic. In comparison to its ancestors the SARS-CoV and MERS-CoV, the novel corona virus SARS-CoV-2 has a faster spread. The transmission of disease is through inhalation of infected droplets. Fever, sore throat, dry cough, body pain and malaise are the common symptoms. Shortness of breath leading to acute respiratory distress syndrome is observed in worse situation. Diagnosis is made through detection of the virus in respiratory secretions. Treatment is symptomatic. COVID-19 has badly affected over 209 countries including Pakistan. According to WHO there are 8,006,427 cases and 436,899 deaths reported due to COVID-19, as of 16th June 2020. Prevention includes isolating the suspected cases while the strict infection control measures must be at employed at the hospitals. Being a neighbor to China and Iran, Pakistan was most vulnerable to COVID-19. In Pakistan first case of COVID-19 was reported on 25 February 2020. 78% COVID-19 positive cases were the pilgrims returning from Iran. To control the spread of the disease, the Government of Pakistan announced the suspension of international and domestic flights. All the educational institutions were closed and a partial lockdown was imposed across the country. Hand hygiene, wearing of face masks and the social distancing was stressed upon. Uptil now, no vaccine against COVID-19 is reported. However, clinical trials are being conducted all over the world. The article throws some light on the origin, pathogenicity, symptoms, diagnostics along with possible therapeutic strategies of the virus and situation of COVID-19 in Pakistan.

End-to-End Protocol for the Detection of SARS-CoV-2 from Built Environments.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019, is a respiratory virus primarily transmitted person to person through inhalation of droplets or aerosols, laden with viral particles. However, as recent studies have shown, virions can remain infectious for up to 72 h on surfaces, which can lead to transmission through contact. Thus, a comprehensive study was conducted to determine the efficiency of protocols to recover SARS-CoV-2 from surfaces in built environments. This end-to-end (E2E) study showed that the effective combination for monitoring SARS-CoV-2 on surfaces includes using an Isohelix swab collection tool, DNA/RNA Shield as a preservative, an automated system for RNA extraction, and reverse transcriptase quantitative PCR (RT-qPCR) as the detection assay. Using this E2E approach, this study showed that, in some cases, noninfectious viral fragments of SARS-CoV-2 persisted on surfaces for as long as 8 days even after bleach treatment. Additionally, debris associated with specific built environment surfaces appeared to inhibit and negatively impact the recovery of RNA; Amerstat demonstrated the highest inhibition (>90%) when challenged with an inactivated viral control. Overall, it was determined that this E2E protocol required a minimum of 1,000 viral particles per 25 cm2 to successfully detect virus from test surfaces. Despite our findings of viral fragment longevity on surfaces, when this method was employed to evaluate 368 samples collected from various built environmental surfaces, all samples tested negative, indicating that the surfaces were either void of virus or below the detection limit of the assay.IMPORTANCE The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (the virus responsible for coronavirus disease 2019 [COVID-19]) pandemic has led to a global slowdown with far-reaching financial and social impacts. The SARS-CoV-2 respiratory virus is primarily transmitted from person to person through inhalation of infected droplets or aerosols. However, some studies have shown that virions can remain infectious on surfaces for days and can lead to human infection from contact with infected surfaces. Thus, a comprehensive study was conducted to determine the efficiency of protocols to recover SARS-CoV-2 from surfaces in built environments. This end-to-end study showed that the effective combination for monitoring SARS-CoV-2 on surfaces required a minimum of 1,000 viral particles per 25 cm2 to successfully detect virus from surfaces. This comprehensive study can provide valuable information regarding surface monitoring of various materials as well as the capacity to retain viral RNA and allow for effective disinfection.

COVID-19 in Children: Clinical Approach and Management.

COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a major public health crisis threatening humanity at this point in time. Transmission of the infection occurs by inhalation of infected droplets or direct contact with soiled surfaces and fomites. It should be suspected in all symptomatic children who have undertaken international travel in the last 14 d, all hospitalized children with severe acute respiratory illness, and asymptomatic direct and high-risk contacts of a confirmed case. Clinical symptoms are similar to any acute respiratory viral infection with less pronounced nasal symptoms. Disease seems to be milder in children, but situation appears to be changing. Infants and young children had relatively more severe illness than older children. The case fatality rate is low in children. Diagnosis can be confirmed by Reverse transcriptase – Polymerase chain reaction (RT-PCR) on respiratory specimen (commonly nasopharyngeal and oropharyngeal swab). Rapid progress is being made to develop rapid diagnostic tests, which will help ramp up the capacity to test and also reduce the time to getting test results. Management is mainly supportive care. In severe pneumonia and critically ill children, trial of hydroxychloroquine or lopinavir/ritonavir should be considered. As per current policy, children with mild disease also need to be hospitalized; if this is not feasible, these children may be managed on ambulatory basis with strict home isolation. Pneumonia, severe disease and critical illness require admission and aggressive management for acute lung injury and shock and/or multiorgan dysfunction, if present. An early intubation is preferred over non-invasive ventilation or heated, humidified, high flow nasal cannula oxygen, as these may generate aerosols increasing the risk of infection in health care personnel. To prevent post discharge dissemination of infection, home isolation for 1–2 wk may be advised. As of now, no vaccine or specific chemotherapeutic agents are approved for children.

Pasteurellosis Status in Ethiopia: A Comprehensive Review

Ethiopia has the largest national livestock populations in Africa. However, the productivity is one of the marginal due to a number of technical and non-technical factors. Infectious diseases like pasteurellosis are highly affecting livestock industry in the country. Pasteurellosis is a multifactorial disease caused by numerous etiologic agents. Mannheimia haemolytica, Bibersteinia trehalosi and Pasteurella multocida cause pasteurellosis in animals and humans. Pasteurella are commensal organisms of healthy animals which can be trigger with stress factors to cause fatal disease in farm animals. Infective agents acquired by inhalation of infected droplets or close contacts among susceptible animals. Pasteurellosis is responsible for huge mortality in feedlot animals worldwide. Haemorrhagic septicemia is an acute and characterized by sudden onset of fever, profuse salivation, severe dyspnea and death in about 24 hours whereas shipping fever causes severe broncho-pneumonia and pleurisy. The diagnosis of the disease is based on the clinical signs, gross pathological lesions, isolation of the pathogens and molecular characterization. Pasteurellosis is complex multifactorial disease difficult to control however, good management, chemotherapy, chemoprophylaxis and early immunization are control and preventive measures. In Ethiopia pasteurellosis is an endemic disease posing a serious threat to the animal productions. However, data on epidemiology, diagnosis, prevention and control is scarce. Therefore, a routine national wide survey encompassing multiple hosts and wider area should be undertaken to figure out prevalence and identify circulating serotypes in different agro ecology to design and implement appropriate interventions.

La peste : mise au point et actualités

Plague is a bacterial zoonosis caused by Yersinia pestis, usually found in fleas and small rodents that constitute the reservoir of the disease. It is transmitted to humans by flea bite, contact with rodents or inhalation of infected droplets. There are three clinical forms: bubonic plague, pulmonary plague and septicemic plague. The usual presentation is a flu-like syndrome possibly accompanied by an inflammatory lymphadenopathy which appears after 1 to 7days of incubation. Bubonic plague has a case fatality rate of about 50% while other forms of plague are almost always fatal without treatment. Diagnosis can be confirmed by usual bacteriological techniques (Gram examination, culture) but also by serological examination, use of rapid diagnostic tests or PCR. Although aminoglycosides are traditionally regarded as the most effective treatment, fluoroquinolones or cyclins are currently recommended in France. Plague is one of the re-emerging diseases according to the WHO and Madagascar suffered in 2017 the most important plague epidemic of the 21st century with more than 2000 cases and 200 deaths. Peru and the Democratic Republic of Congo are also considered endemic areas. Public health measures and a relentless fight against poverty are the cornerstone of the control of the disease. Vaccine improvement in endemic areas may also play an important role.

Human ectoparasites and the spread of plague in Europe during the Second Pandemic

Plague, caused by the bacterium Yersinia pestis, can spread through human populations by multiple transmission pathways. Today, most human plague cases are bubonic, caused by spillover of infected fleas from rodent epizootics, or pneumonic, caused by inhalation of infectious droplets. However, little is known about the historical spread of plague in Europe during the Second Pandemic (14-19th centuries), including the Black Death, which led to high mortality and recurrent epidemics for hundreds of years. Several studies have suggested that human ectoparasite vectors, such as human fleas (Pulex irritans) or body lice (Pediculus humanus humanus), caused the rapidly spreading epidemics. Here, we describe a compartmental model for plague transmission by a human ectoparasite vector. Using Bayesian inference, we found that this model fits mortality curves from nine outbreaks in Europe better than models for pneumonic or rodent transmission. Our results support that human ectoparasites were primary vectors for plague during the Second Pandemic, including the Black Death (1346-1353), ultimately challenging the assumption that plague in Europe was predominantly spread by rats.

Evaluation of Yersinia pestis Transmission Pathways for Sylvatic Plague in Prairie Dog Populations in the Western U.S.

Sylvatic plague, caused by the bacterium Yersinia pestis, is periodically responsible for large die-offs in rodent populations that can spillover and cause human mortalities. In the western US, prairie dog populations experience nearly 100% mortality during plague outbreaks, suggesting that multiple transmission pathways combine to amplify plague dynamics. Several alternate pathways in addition to flea vectors have been proposed, such as transmission via direct contact with bodily fluids or inhalation of infectious droplets, consumption of carcasses, and environmental sources of plague bacteria, such as contaminated soil. However, evidence supporting the ability of these proposed alternate pathways to trigger large-scale epizootics remains elusive. Here we present a short review of potential plague transmission pathways and use an ordinary differential equation model to assess the contribution of each pathway to resulting plague dynamics in black-tailed prairie dogs (Cynomys ludovicianus) and their fleas (Oropsylla hirsuta). Using our model, we found little evidence to suggest that soil contamination was capable of producing plague epizootics in prairie dogs. However, in the absence of flea transmission, direct transmission, i.e., contact with bodily fluids or inhalation of infectious droplets, could produce enzootic dynamics, and transmission via contact with or consumption of carcasses could produce epizootics. This suggests that these pathways warrant further investigation.

Spatial distribution of human respiratory droplet residuals and exposure risk for the co-occupant under different ventilation methods

Since the severe acute respiratory syndrome (SARS) epidemics in 2003, more attention is given to ventilation effects on airborne infection control. Questions remain on whether the three typical air distribution methods can have significant differences in reducing the infections between occupants in a space. This study adopts a novel modeling approach by including respiratory thermal manikins in the computational fluid dynamics domain to directly assess the inhalation dose of infectious droplets. Both the initial momentum of a coughing jet and the consequent droplet dispersion due to room airflow are simulated in detail. The preliminary results indicate that including the co-occupant in the modeling domain can present a more reliable exposure. The droplets movements are very complicated, and the whole exposure process can be roughly separated as two stages—a direct exposure at first and a later indirect exposure. The effects of the stratified air distribution systems on the co-occupant's inhalation of infectious droplets cannot easily be concluded. Although the inhaled dose is lowest under displacement ventilation for smaller droplets, under-floor air distribution can achieve the lowest inhalation for larger droplets.

EPIZOOTIOLOGICAL CHARACTERISTICS OF BOVINE TUBERCULOSIS IN SOUTH BAČKA REGION

Bovine tuberculosis caused by Mycobacterium bovis is a chronicle, infective disease associated with formation of specific inflammatory granulomas. Infection usually remains subclinical for a long period, but even when the clinical are present, they are not pathognomic. Bovine tuberculosis can spread to humans through inhalation of infectious droplets and by ingestion of raw milk, and on the rare occasion through consumption of meat products. Since the disease remains a great economic concern for cattle production operations and due to its zoonotic nature, most of the countries initiated a program for the control and eradication of tuberculosis in domestic animals. In South Baåka region (SBD) three tuberculous foci were detected on the territory of Žabalj, Novi Sad and Titel municipality. The first 11 reactors were detected in the year 2004 during the diagnostic examination that was conducted according to the Program of Measures for infectious disease survaillance. The number of animals with a positive reaction to the intradermal tuberculin test was 113, 54 and 142, in 2006, 2007 and 2008, respectively. The diagnosis was further confirmed by gama-interferon test, gross pathology and histopathological examination, and definitively confirmed by M. bovis isolation from the lymph node and lung lesions. The number of estimated tuberculin reactors was 320, located in six settlements and 37 husbandries. The percent of infected animals in some herds ranged from 11.10 to 59.18%. The objective of this investigation was to determine the routes of infection and to identify risk factors that contributed to the tuberculosis breakdown in the tuberculous hot spots. An epizootiological evaluation revealed that the high herd prevalence and high animal incidence of bovine TBC in South Baåka region was associated with the following factors: lack of TBC diagnosis in pastured animals in swampy areas for a long period, grazing areas are often flooded resulting in bad quality fodder and cattle malnutrition, presence of other domestic animals on the pastures, co-mingling of animals from different herds is frequent, common water through, presence of different wild animal species on pasture (as a potential reservoir of the disease), uncontrolled movement and illegal trade of infected animals, natural breeding as well as overpopulation in the sheds during winter housing.

Swine flu

The recent outbreak of human infection with a novel Swine-Origin Influenza A (H1N1) virus is spreading rapidly through sustained human-to-human transmission in multiple countries. Human-to-human transmission occurs by inhalation of infectious droplets and droplet nuclei, and by direct contact, which is facilitated by air and land travel and social gatherings. The most frequently reported symptoms are fever, cough, myalgia, and sore throat. Detailed contact and travel histories and knowledge of viral activity in community are essential for prompt case detection by the health personnel. Real-time Reverse Transcriptase-Polymerase Chain Reaction analysis of throat swabs or lower respiratory samples is a sensitive means of diagnosis. Use of oral oseltamivir may be warranted for the treatment of severe illness.

La peste

The plague has been one of the most devastating diseases of human history. Despite major advances in diagnosis, prevention, and treatment, it has not been possible to eradicate this infection. Plague is still active in Africa, in Asia and in the Americas, and is classified as a currently re-emerging disease. The plague is mainly a disease of rodents, which is transmitted by fleabites. Humans develop two main clinical forms: bubonic plague (following bites of infected fleas, lethal in 50–70% of the cases in less than a week if an appropriate treatment is not started rapidly), and pneumonic plague (after inhalation of infected droplets, lethal in less than three days in 100% of cases without immediate treatment). Y. pestis, the causative agent of plague, is usually sensitive to most antibiotics, but the first multi-resistant strain was recently described. No efficient and safe vaccines are currently available. The plague bacillus is one of the few organisms that could be used for biological warfare.

Immunity in Tuberculosis

In this review various aspects of tuberculo-immunity and of the pathogenesis and diagnosis of tuberculosis (TB) are examined in the light of current immunological knowledge. Successful resistance in TB is not easily predicted by the presence or absence of an immune response but it is a balance between the various types of immune responses of the host and the strength of the infecting bacterial strain for that individual host. Primary infection is usually acquired through the inhalation of infected droplets; the probability of the development of disease among TB-positive individuals varies from 30/100000 in Denmark to 600/100000 in some Eskimo populations. Even if TB were eradicated however sporadic cases would continue to occur since for TB acquired from the environment control would necessitate lowering the rate of infection in bird and animal groups. 4 groups of TB patients include: 1) those in which cell-mediated activity is fully active 2) those in which cell-mediated immunity is not detected 3) an intermediate group leaning more towards group 1 and 4) an intermediate group leaning towards group 2. The cells involved in the outcome of a TB infection macrophages and lymphocytes are discussed individually. The thick cell wall of the Mycobacterium tuberculosis resists destruction by enzymes antibodies and other factors and requires a mechanism that will activate macrophages and histocytes to breach this cell wall and lead to cell death. A vaccine against TB should be long lasting such as BCG although BCG has not been found to be effective in all populations. The degree of immune response to TB will depend on: 1) the degree of sensitivity the mycobacterial species is capable of inducing and 2) how much of this sensitivity is cross-reactive with M. tuberculosis. High effectiveness of BCG immunization has been related to a low endemicity of non-TB mycobacteria; it should be administered early in life in countries with a high prevalence of TB. The pathogenesis and pathology of TB is discussed as are immunological tests such as the tuberculin tests which indicates TB sensitivity in vitro tests for cellular hypersensitivity and dual skin tests. Future research should focus on the BCG vaccine better in vitro tests and standardization of reagents.