10 Tips to Prevent Infections

It may seem a daunting task to keep yourself and your loved ones free of infections. Beyond the obvious—steering clear of runny noses and hacking coughs—you may be wondering about some other practical ways of staying infection-free. Your skin acts as a natural barrier against harmful microbes that cause infections, but smart “bugs” have found alternative routes to get into your body and cause infection. By making a few simple behavioral changes (which ultimately reduce their access into your body), you can easily prevent the spread of many infectious diseases.

  1. Wash your hands frequently. Did you know that microbes can live on inert surfaces anywhere from a few minutes to several months? Imagine these disease-causing microbes living on your computer keyboard, your light-switch, or even on the pedestrian-crossing button next to the crosswalk!Surprisingly, most people don’t know the best way to effectively wash their hands. The CDC recommends washing thoroughly and vigorously with soap and water for at least 20 seconds, followed by hand-drying with a paper towel. In the absence of running water, an alcohol-based hand gel or wipe will suffice, although nothing beats good ol’ soap and water. This takes about as long as it does to sing “Happy Birthday”, so some hospitals recommend washing your hands for the duration of this simple tune!
  2. Don’t share personal items. Toothbrushes, towels, razors, handkerchiefs, and nail clippers can all be sources of infectious agents (bacteria, viruses, and fungi). In kindergarten, you were taught to share your toys, but keep your hands to yourself. Now try to remember to keep personal items to yourself as well!
  3. Cover your mouth when you cough or sneeze. In a similar vein, good personal hygiene includes not only personal cleanliness, but also the age-old practice of covering your mouth when you cough or sneeze. Why is this important if you aren’t sick? For most infections, the disease-causing microbe has already started growing and dividing long before any symptoms begin to show. Coughing or sneezing can spread these germs through microscopic droplets in the air. The current recommendation is to cover your mouth with your arm, sleeve, or crook of the elbow, rather than using your hands. Read more »

H5N1 (avian / bird flu) pandemic educational information

One of the primary concerns is that the virus could quickly spread across countries as various birds follow their migration routes. In response, countries have begun planning in anticipation of an outbreak. While short-term strategies to deal with an outbreak focus on limiting travel and culling and vaccinating poultry, long-term strategies require substantial changes in the lifestyles of the most at-risk populations.

WHO announced on November, 16, 2005 that an outbreak is most likely to hit the Hong Kong Special Administrative issue by mid-December of this year. “If it were to hit in a highly residential area like Tin Hau, it would be sure to spread like wildfire.” Dr. N Column, Head of Epidemic Prevention announced.

The WHO divides a pandemic into six phases, ranging from minimal risk of an outbreak to full scale pandemic. Most health authorities categorize the situation as of 2005 at Phase 3, by which is meant that human infections of a new sub-type has occurred but there is little evidence of sustained human-to-human transmission.

Avian Influenza (Bird Flu)

Avian influenza, or �bird flu�, is a contagious disease of animals caused by viruses that normally infect only birds and, less commonly, pigs. Avian influenza viruses are highly species-specific, but have, on rare occasions, crossed the species barrier to infect humans.

In domestic poultry, infection with avian influenza viruses causes two main forms of disease. The so-called �low pathogenic� form commonly causes only mild symptoms (ruffled feathers, a drop in egg production) and may easily go undetected. The highly pathogenic form is far more dramatic. It spreads very rapidly through poultry flocks, causes disease affecting multiple internal organs, and has a mortality that can approach 100%, often within 48 hours.

Influenza A viruses have 16 H subtypes and 9 N subtypes. Only viruses of the H5 and H7 subtypes are known to cause the highly pathogenic form of the disease. On present understanding, H5 and H7 viruses may circulate and infect poultry flocks in their low pathogenic form. The viruses can then mutate, usually within a few months, into the highly pathogenic form. This is why the presence of an H5 or H7 virus in poultry is always cause for concern, even when the initial signs of infection are mild. Read more »

Anemia

Background
Anemia, like a fever, is a symptom of disease that requires investigation to determine the underlying etiology. Often, practicing physicians overlook mild anemia. This is similar to failing to seek the etiology of a fever. The purpose of this article is to provide a method of determining the etiology of an anemia.

Anemia is strictly defined as a decrease in red blood cell (RBC) mass. Methods for measuring RBC mass are time consuming, are expensive, and usually require transfusion of radiolabeled erythrocytes. Thus, in practice, anemia is usually discovered and quantified by measurement of the RBC count, hemoglobin (Hb) concentration, and hematocrit (Hct). These values should be interpreted cautiously because they are concentrations affected by changes in plasma volume. For example, dehydration elevates these values, and increased plasma volume in pregnancy can diminish them without affecting the RBC mass.
Pathophysiology
Erythroid precursors develop in bone marrow at rates usually determined by the requirement for sufficient circulating Hb to oxygenate tissues adequately. Erythroid precursors differentiate sequentially from stem cells to progenitor cells to erythroblasts to normoblasts in a process requiring growth factors and cytokines. This process of differentiation requires several days. Normally, erythroid precursors are released into circulation as reticulocytes.

Reticulocytes remain in the circulation for approximately 1 day before reticulin is excised by reticuloendothelial cells with the delivery of the mature erythrocyte into circulation. The mature erythrocyte remains in circulation for about 120 days before being engulfed and destroyed by phagocytic cells of the reticuloendothelial system. Read more »

Dengue Fever

Background
Dengue, the most common arboviral illness transmitted worldwide, is caused by infection with 1 of the 4 serotypes of dengue virus, family Flaviviridae, genus Flavivirus (single-stranded nonsegmented RNA viruses). Dengue is transmitted by mosquitoes of the genus Aedes, which are widely distributed in subtropical and tropical areas of the world, and is classified as a major global health threat by the World Health Organization (WHO).

Initial dengue infection may be asymptomatic (50%-90%), may result in a nonspecific febrile illness, or may produce the symptom complex of classic dengue fever (DF). A small percentage of persons who have previously been infected by one dengue serotype develop bleeding and endothelial leak upon infection with another dengue serotype. This syndrome is termed dengue hemorrhagic fever (DHF), although dengue vasculopathy has been proposed as a better term, as fluid loss into tissue spaces can lead to prolonged shock and complications, including gastrointestinal bleeding, a greater fatality risk than bleeding per se. Some patients with dengue hemorrhagic fever develop shock (dengue shock syndrome [DSS]), which may cause death.

Dengue virus transmission follows two general patterns—epidemic dengue and hyperendemic dengue. Epidemic dengue transmission occurs when dengue virus is introduced into a region as an isolated event that involves a single viral strain. If the number of vectors and susceptible pediatric and adult hosts is sufficient, explosive transmission can occur, with an infection incidence of 25%-50%. Mosquito-control efforts, changes in weather, and herd immunity contribute to the control of these epidemics. Transmission appears to begin in urban centers and then spreads to the rest of a country. This is the current pattern of transmission in parts of Africa and South America, areas of Asia where the virus has reemerged, and small island nations. Travelers to these areas are at increased risk of acquiring dengue during these periods of epidemic transmission.

Hyperendemic dengue transmission is characterized by the continuous circulation of multiple viral serotypes in an area where a large pool of susceptible hosts and a competent vector (with or without seasonal variation) are constantly present. This is the predominant pattern of global transmission. In these populations, antibody prevalence increases with age and most adults are immune. Hyperendemic transmission appears to be a major risk for dengue hemorrhagic fever. Travelers to these areas are more likely to be infected than are travelers to areas that experience only epidemic transmission. Read more »

Rabies

Background
Rabies is a viral disease that affects the CNS. The genus Lyssavirus contains more than 80 viruses. Classic rabies, the focus of this article, is the prototypical human Lyssavirus pathogen. Ten viruses are in the rabies serogroup, most of which only rarely cause human disease. The genus Lyssavirus, rabies serogroup, includes the classic rabies virus, Mokola virus, Duvenhage virus, Obodhiang virus, Kotonkan virus, Rochambeau virus, European bat Lyssavirus types 1 and 2, and Australian bat Lyssavirus. In 1997, an unusual bat Lyssavirus caused a brief outbreak of a rabieslike illness in Australia.

The fatal madness of rabies has been described throughout recorded history, and its association with rabid canines is well known. For centuries, dog bites were treated prophylactically with cautery, unfortunately, with predictable results. In the 19th century, Pasteur developed a vaccine that successfully prevented rabies after inoculation and launched a new era of hope in the management of this uniformly fatal disease. Rabies is recognized as a zoonosis worldwide. Animal-control and vaccination strategies currently supersede postexposure prophylaxis in preventing the spread of rabies. Through such programs, rabies has been eliminated in several nations and some areas in the US territories.

Human rabies reflects the prevalence of animal infection and the extent of contact this population has with humans. Less than 5% of cases in developed nations occur in domesticated dogs; however, unvaccinated dogs serve as the main reservoir worldwide. Undomesticated canines, such as coyotes, wolves, jackals, and foxes, are most prone to rabies and serve as reservoirs. These reservoirs allow rabies to remain an indefinite public health concern, and ongoing public health measures are critical to its control. Raccoons, skunks, and insect-eating bats remain the prime vectors in the United States, followed by cats and cattle. Increasingly in the United States, the source of exposures cannot be identified, but the risk of death from rabies is exceedingly low, with fewer than 5 cases documented per year. Opossums are rarely infected and are not considered a likely risk for exposure. Read more »

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