Parasites & Vectors volume 11, Article number: 264 (2018)
Dengue creates a staggering epidemiological and economic burden for endemic countries. Without a specific therapy and with a commercial vaccine that presents some problems relative to its full effectiveness, initiatives to improve vector... control strategies, early disease diagnostics and the development of vaccines and antiviral drugs are priorities. In this study, we present the probable origins of dengue in America and the trajectories of its spread. Overall, dengue diagnostics are costly, making the monitoring of dengue epidemiology more difficult and affecting physicians’ therapeutic decisions regarding dengue patients, especially in developing countries. This review also highlights some recent and important findings regarding dengue in Brazil and the Americas. We also summarize the existing DENV polymerase chain reaction (PCR) diagnostic tests to provide an improved reference since these tests are useful and accurate at discriminating DENV from other flaviviruses that co-circulate in the Americas. Additionally, these DENV PCR assays ensure virus serotyping, enabling epidemiologic monitoring.
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Chapters
0:00 Introduction
0.27 Causes of Dengue Fever
1:09 Signs and Symptoms of Dengue Fever
2:30 Dengue Hemorrhagic Fever
3:53 Diagnosis of Dengue Fever
4:10 Treatment of Dengue Fever
Dengue fever is a mosquito-borne tropical disease caused by the dengue virus. Symptoms typically beg...in three to fourteen days after infection. This may include a high fever, headache, vomiting, muscle and joint pains, and a characteristic skin rash.Recovery generally takes two to seven days. In a small proportion of cases, the disease develops into the life-threatening dengue hemorrhagic fever, resulting in bleeding, low levels of blood platelets and blood plasma leakage, or into dengue shock syndrome, where dangerously low blood pressure occurs.
Dengue is spread by several species of mosquito of the Aedes type, principally A. aegypti.The virus has five different types;infection with one type usually gives lifelong immunity to that type, but only short-term immunity to the others. Subsequent infection with a different type increases the risk of severe complications. A number of tests are available to confirm the diagnosis including detecting antibodies to the virus or its RNA.
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Trachoma causes more vision loss and blindness than any other infection in the world. This disease is caused by Chlamydia trachomatis bacteria. Other variants or strains of these bacteria can cause a sexually transmitted infection (chlamydia) and disease in lymph nodes.
This is photomicrograph ...of a conjunctival smear that revealed the presence of what are known as, intracytoplasmic inclusions Trachoma is easily spread through direct personal contact such as from fingers, through shared towels and clothes, and through flies that have been in contact with the eyes or nose of an infected person. When left untreated, repeated Chlamydia trachomatis infections in the eye can cause severe scarring on the inside of the eyelid. This can cause the eyelashes to scratch the cornea (trichiasis). In addition to causing pain, trichiasis permanently damages the cornea and can lead to irreversible blindness.
Chlamydia trachomatis infections spread in areas that lack access to safely managed drinking water and sanitation systems. Trachoma affects the most resource-limited communities in the world. Globally, almost 1.9 million people have vision loss because of trachoma, and it causes 1.4% of all blindness worldwide.1 In 2021, 136 million people lived in trachoma-endemic areas and were at risk of trachoma blindness.
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Trachoma is one of oldest infectious diseases known to humans. It is caused by the bacteria Chlamydia trachomatis, which is transmitted through contact with eye secretions of infected people (shared use of towels and handkerchiefs, contact with fingers, etc.), as well by flies that help spread it.
Trachoma is the leading infectious cause of blindness worldwide. It is caused by an obligate intracellular bacterium called Chlamydia trachomatis. The infection is transmitted by direct or indirect transfer of eye and nose discharges of infected people, particularly young children who harbour the pr...incipal reservoir of infection. These discharges can be spread by particular species of flies.
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Research and Reports in Tropical Medicine 2022:13 25–40
Chagas disease (CD) or American trypanosomiasis is a neglected parasitic disease associated with significant mortality and morbidity that includes long-term disability, social stigma and a mental health toll. Perceived as a disease of the ve...ry poor, this infection, once limited to rural areas of Latin America (LA), has now spread via migration to non-endemic areas and countries, where transmission is maintained via non-vectorial routes.
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It is estimated that, in Latin America alone, between 6 and 8 million people are infected with the parasite, and 99% of these are not receiving treatment, either because they are unaware of their infection or because they do not know that treatment exists. The potential spread of the disease is also... a cause for considerable concern: 65 million people live in areas of exposure and are at risk of contracting Chagas disease, and 28,000 new cases occur every year.
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Chagas disease, or American trypanosomiasis, is a condition that causes gradual organ damage. Without treatment, it can be fatal.
This article explains where the T. cruzi parasite is most common and how it can spread. It also outlines the symptoms of Chagas disease and the treatment options avail...able.
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First discovered more than 100 years ago, Chagas disease continues to affect more than six million people worldwide and is one of the most prevalent public health problems in Latin America and, increasingly, on a global scale. In the last decades, migratory patterns have spread the disease to areas ...where it was previously unknown, including the United States of America (USA), Europe and the Western Pacific region. With an estimated 75 million individuals at risk of infection, Chagas disease is becoming a global health challenge with significant social and economic burdens for the people affected by it.
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About six to seven million people worldwide, mostly in Latin America, are estimated to be infected with
Trypanosoma cruzi, the parasite that causes Chagas disease (WHO data from 2021). Chagas disease is
found mainly in endemic areas of 21 Latin American countries. Chagas disease was once entirely
...
confined to rural areas but in the last decades, due to population movements, most infected people live
in urban settings and the disease has spread to other continents. The burden of disease is due to its
chronic progression with people still suffering years later after initial infection.
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Arsenical monotherapies were previously very successful for treating human African trypanosomiasis (HAT).
Melarsoprol resistance emerged as early as the 1970s and was widespread by the late 1990s.
Melarsoprol resistance represents the only example of widespread drug resistance in HAT patients wher...e the genetic mechanism has been established.
The current goal of elimination of HAT as a public health problem by 2020 may be undermined by the emergence and spread of resistance to current or new drugs.
Insights into potential resistance mechanisms for current and new drugs will facilitate predictions of the likelihood of resistance and will also facilitate rational approaches to minimizing, monitoring, and tackling the future emergence of resistance.
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Human scabies is caused by an infestation of the skin by the human itch mite (Sarcoptes scabiei var. hominis). The microscopic scabies mite burrows into the upper layer of the skin where it lives and lays its eggs.
Scabies is found worldwide and affects people of all races and social classes. Scabi...es can spread rapidly under crowded conditions where close body and skin contact is frequent. Institutions such as nursing homes, extended-care facilities and prisons are often sites of scabies outbreaks. Child care facilities also are a common site of scabies infestations.
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When a person is infested with scabies mites the first time, symptoms typically take 4-8 weeks to develop after being infested. However, an infested person can transmit scabies, even if they do not have symptoms. Scabies usually is passed by direct, prolonged skin-to-skin contact with an infested pe...rson. However, a person with crusted (Norwegian) scabies can spread the infestation by brief skin-to-skin contact or by exposure to bedding, clothing, or even furniture that he/she has used.
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Scabies is an infestation of the skin by the human itch mite (Sarcoptes scabiei var. hominis). The microscopic scabies mite burrows into the upper layer of the skin where it lives and lays its eggs. The most common symptoms of scabies are intense itching and a pimple-like skin rash. The scabies mite... usually is spread by direct, prolonged, skin-to-skin contact with a person who has scabies.
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The WHO continuously reviews available data on SARS-CoV-2 variants of concern. For this version, the global epidemiological
situation of the COVID-19 pandemic as of 21 January 2022 – at a time when the Omicron VOC had been identified in 171
countries across all six WHO Regions and was rapidly re...placing Delta worldwide – was considered Omicron has a substantial growth advantage, higher secondary attack rates and a higher observed reproduction number than Delta.
There is now significant evidence that immune evasion contributes to the rapid spread of Omicron. Other factors may be a shorter
serial interval (by about 0.8 to 1.2 days compared to Delta) and potential increased intrinsic transmission fitness . There is
growing evidence that with Omicron, there is lower vaccine effectiveness (VE) against infection and symptomatic disease soon after vaccination compared to Delta. There is also evidence of accelerated waning of VE over time of the primary series against infection and symptomatic disease for the studied vaccines. Further studies are required to better understand the drivers of transmission and declining incidence in various settings. These factors include the intrinsic transmission fitness properties of the virus, degree of immune evasion, vaccination coverage and level of vaccine-derived and post-infection immunity, levels of social mixing and degree of application of public health and social measures (PHSM).
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Each year 1–2 million people are diagnosed with a tropical disease called leishmaniasis, which is caused by single-celled parasites. People are infected when they are bitten by sandflies carrying the parasite, and often develop skin lesions around the bite site. Though mild cases may recover on th...eir own or with treatment, sometimes the parasites multiply and spread elsewhere causing further skin lesions and facial disfigurement. Furthermore, the parasites can also infect internal organs such as the spleen and the liver, which without treatment can be fatal.
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The majority of developing countries will fail to achieve their targets for Universal Health Coverage (UHC)1 and the health- and poverty-related Sustainable Development Goals (SDGs) unless they take urgent steps to strengthen their health financing. Just over a decade out from the SDG deadline of 20...30, 3.6 billion people do not receive the most essential health services they need, and 100 million are pushed into poverty from paying out-of-pocket for health services. The evidence is strong that progress towards UHC, core to SDG 3, will spur inclusive and sustainable economic growth, yet this will not happen unless countries achieve high-performance health financing, defined here as funding levels that are adequate and sustainable; pooling that is sufficient to spread the financial risks of ill-health; and spending that is efficient and equitable to assure desired levels of health service coverage, quality, and financial protection for all people— with resilience and sustainability.
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The CDC document titled "KOLERA: Senk (5) Etap Debaz Yo Pou Prevansyon" outlines five essential steps for preventing cholera. It emphasizes the importance of using treated water for drinking and food preparation, washing hands thoroughly with soap and safe water, cooking food thoroughly and consumin...g it while hot, using latrines or properly burying feces to avoid open defecation, and cleaning and disinfecting areas contaminated with feces using a solution of one part household bleach to nine parts water. These measures are critical to controlling and preventing the spread of cholera, especially in areas affected by outbreaks.
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Cholera is a major health risk in many parts of the world, affecting millions of people every year. Since mid-2021, the world has been facing an acute upsurge of the 7th cholera pandemic, which is characterized by the number, size and concurrence of multiple outbreaks, the spread to areas that had b...een free of cholera for decades and alarmingly high mortality rates. The mortality associated with these outbreaks is of particular concern as many countries have reported higher case fatality ratios (CFR) than in previous years
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Infection prevention and control (IPC) in a CTC/ CTU IPC are all practical measures taken in the healthcare facility to prevent harm caused by infections to patients, health workers and communities.
The main goal of IPC in the cholera response is to
• To reduce transmission of health care-as...sociated infections of cholera and any other infectious disease
• To enhance the safety of staff, patients and visitors
• To enhance the ability of the organization/health care facility to respond to an outbreak
• To reduce the risk of the hospital (health care facility) itself amplifying the outbreak
Water, Sanitation and Hygiene (WASH)
WASH are all measures taken to guarantee environmental hygiene, safe water of all used within the health facility. It encompasses water, sanitation, waste management, cleaning within the health facility which in this case is CTU/C. A complete WASH package in the CTU/CTC reduces the risk of spread of Vibrio cholerae inside and outside the CTC/CTU.
The probability of spreading or acquiring cholera through a CTC/CTU can be highly reduced when proper IPC and WASH measures are respected, followed and monitored. These measures are, in principle, valid in CTC/CTUs and ORPs, although they need to be adapted to the specific characteristics of the facility concerned.
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