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 »

Influenza

Background
Influenza virus infection, one of the most common infectious diseases, is a highly contagious airborne disease that causes an acute febrile illness and results in variable degrees of systemic symptoms, ranging from mild fatigue to respiratory failure and death. These symptoms contribute to significant loss of workdays, human suffering, mortality, and significant morbidity. The 1918-1919 H1N1 type influenza pandemic killed an estimated 20-50 million persons, with 549,000 deaths in the United States alone.

Accurately diagnosing influenza A or B infection based solely on clinical criteria is difficult because of the overlapping symptoms caused by the various viruses associated with upper respiratory tract infection (URTI). In addition, several serious viruses, including adenoviruses, enteroviruses, and paramyxoviruses, may initially cause influenzalike symptoms. The early presentation of mild or moderate cases of flavivirus infections (eg, dengue) may initially mimic influenza. For example, some cases of West Nile fever acquired in New York in 1999 were clinically misdiagnosed as influenza.

Patients with influenza frequently present with various symptoms shared by many other viral infections. In the northern and southern hemispheres, these symptoms are more common in the winter months. As a result, during the winter, clinics and emergency department waiting rooms fill with patients who have influenza or other URTIs.
Pathophysiology
Influenza results from infection with 1 of 3 basic types of influenza virus—A, B, or C—which are classified within the family Orthomyxoviridae. These single-stranded RNA viruses are structurally and biologically similar but vary antigenically.

The RNA core consists of 8 gene segments surrounded by a coat of 10 (influenza A) or 11 (influenza B) proteins. Immunologically, the most significant surface proteins include hemagglutinin and neuraminidase. The viruses are typed based on these proteins. For example, influenza A subtype H3N2 expresses hemagglutinin 3 and neuraminidase 2.

The most common prevailing influenza A subtypes that infect humans are H1N1 and H3N2. Each year, the trivalent vaccine used worldwide contains A strains from H1N1 and H3N2, along with an influenza B strain.

Influenza virus infection occurs after transfer of respiratory secretions from an infected individual to a person who is immunologically susceptible. If not neutralized by secretory antibodies, the virus invades airway and respiratory tract cells. Once within host cells, cellular dysfunction and degeneration occur, along with viral replication and release of viral progeny. Systemic symptoms result from inflammatory mediators, similar to other viruses. The incubation period of influenza ranges from 18-72 hours.

Influenza A is generally more pathogenic than influenza B. Influenza A is a zoonotic infection, and more than 100 types of influenza A infect most species of birds, pigs, horses, dogs and seals. Indeed, the 1918 pandemic that resulted in millions of human deaths worldwide is believed to have originated from a virulent strain of H1N1 from pigs or birds. Recently, scientists obtained and sequenced the 1918 H1N1 strain from a frozen corpse found in Alaska. The virus was reconstructed at the Centers for Disease Control and Prevention (CDC) laboratory in Atlanta and was found to be highly lethal when tested in mice; the virus was also found to be lethal to chicken embryos. This unique N1 neuraminidase is being studied in order to provide better insight into the N1 found in H5N1, the type responsible for avian influenza (also known as bird flu). Read more »