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Extensively Drug Resistant Tuberculosis (XDR-TB)

July 2007

The news story seemed reminiscent of a Keystone Kops cinema: police and health officials chasing a handsome, healthy-looking 31-year-old globe-trotting attorney Andrew Speaker, and his beautiful bride, through city after city in at least 5 countries, being eluded at hotels, airports, and border checkpoints, only to have the gentleman turn himself in at a New York City hospital, and finally having agents of the Centers of Disease Control and Prevention (CDC) put him into strict isolation for being infected with a deadly and dangerous contagion - tuberculosis (TB)! Wait - is TB dangerous? Isn't TB easily treatable and curable?

What is Extensively Drug Resistant-TB (XDR-TB)? TB is caused by the micro-organism Mycobacterium tuberculosis (MTb). XDR-TB is a strain of MTb resistant not only to the first-line anti-TB drugs (rifampicin and isoniazid), but also to the best second-line drugs, fluoroquinolones, and at least one of the injectable drugs (i.e., amikacin, kanamycin, or capreomycin). This leaves very few treatment options for the patient diagnosed with XDR-TB. According to the aid agency, Doctors Without Borders, treatment for XDR-TB is non-existent in many countries. Health officials think Andrew Speaker may have been infected when he visited Asia as a hospital fundraiser.

Each year, around the world, an estimated 450,000 patients are diagnosed with multiple drug resistant TB, and only two-thirds of them are cured. The World Health Organization (WHO) has confirmed 269 cases of XDR-TB in 35 countries, including the United States. About 85% of these patients are expected to die as a result of this disease. The worst health ramifications come to those who are infected with HIV/AIDS - approximately 90% die within months of contracting TB. According to the CDC, there have been 49 XDR-TB cases in the US since 1993. In March 2007 Italy reported the first case of a patient with TB resistant to "all known drugs." Generally speaking, resistant TB resulted when people self-prescribed or otherwise did not take their antibiotics as directed.

What are the symptoms of XDR-TB? Symptoms of TB disease can vary depending on what part of the body is affected. However, the disease is only contagious when it is located in the lungs or throat. General symptoms include feelings of sickness or weakness, weight loss, fever, and night sweats. Active pulmonary TB disease symptoms may also include coughing, chest pain, and hemoptysis (coughing up blood).

How do I protect myself when I travel? Singing, coughing, sneezing, or speaking can aerosolize MTb into the air where it can "float" for several hours, depending on the environment. Persons who breathe in the air containing MTb can become infected. Airline travel carries a relatively low risk of infection to TB, as TB transmission requires prolonged close contact with someone who is highly infected. However, travelers should avoid high-risk settings where few or no infection control measures are in place, such as crowded hospitals, prisons, homeless shelters, and other settings where susceptible persons come in contact with persons with active TB disease. A TB skin test or the QuantiFERON®-TB Gold blood test can help determine if a person has been exposed to MTb. Final diagnosis for TB, and especially for XDR TB, may take from 6 to 16 weeks.

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Hand Hygiene

February 2009

Of all the measures used to reduce the transmission of disease, Hand Hygiene has been shown to be the most effective, most convenient, and easiest to perform. It is also the most often neglected or improperly performed measure. While hand-washing is old news, Hand Hygiene is a relatively new idea. Properly "performed" Hand Hygiene involves both handwashing and "hand awareness." Awareness of: 1) What the hands were doing before (were in a clean or soiled area, performing a clean or sterile procedure, or performing a task that might have contaminated the hands) and 2) What the hands will be doing next (entering a clean or soiled area, performing a clean or sterile procedure, or performing a task that will result in hand contamination). In other words, anticipating and preparing for what contaminated material the hands may be exposed to.

Hand awareness is especially important when the hands are gloved. Gloves used by health care workers (HCWs) in the performance of patient care are very thin and sustain microscopic tears easily. To ensure the best protection, HCWs should protect gloved hands from unnecessary contact with environmental surfaces and guard them from tearing. Besides protecting the HCW from contamination, gloves can also protect contaminated areas, e.g. wounds, from additional contamination. "Cross contamination" occurs when pathogens are moved or transmitted from an infected area to a non-infected area where they can cause harm. Therefore, change gloves and wash hands during patient care if the hands move from a contaminated body-site (e.g., perineal area) to a clean body-site. Washing hands after doffing gloves can remove soilage or germs that may have passed through the gloves to the hands.

Wash hands with either soap and water or an alcohol-based sanitizer. According to the Centers for Disease Control and Prevention (CDC) Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings 2007 "...alcohol based products for hand disinfection are preferred over antimicrobial or plain soap and water because of their superior microbiocidal activity, reduced drying of the skin, and convenience." The Food and Drug Administration (FDA) recommends alcohol-based hand sanitizers have a concentration of 60% to 95% ethanol or isopropanol, the concentration range of greatest germicidal efficacy. However, soap and water is still preferred for a) removing visible soilage with blood or body fluids, b) visible contamination with proteinaceous material, c) any contact with spores, e.g. Clostridium difficile, d) during a gastrointestinal infection outbreaks, and e) food preparation.

Other Key Hand Hygiene Concepts

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Hepatitis B (March 2004)


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Infections caused by C. trachomatis (CT) and N. gonorrhoeae (NG)

Infections caused by C. trachomatis (CT) and N. gonorrhoeae (NG)are two of the most common sexually transmitted diseases (STD) in the United States and worldwide. Each may cause asymptomatic infections, compounding the problem of diagnosis and contributing to the spread of disease. The application of sensitive and specific screening methods for the diagnosis of CT and GC infection is an important tool for controlling the spread of these organisms and reducing the serious complications of untreated disease.

There has been a revolution in diagnostic methodology in recent years with the introduction of nucleic acid testing. Estimates of prevalence of infection determined in the past by tissue culture or antigen detection methods were gross underestimates. NAAT offers the highest sensitivity: 96-99% for CT and NG, and highest specificity: 96-99% for CT and NG. Nucleic acid amplification tests (NAAT) have consistently exceeded the sensitivities and specificities of non-NAAT methods (culture and indirect fluorescent antibody testing) in the detection of these organisms. The CDC, therefore, recommends use of a NAAT to screen for genitourinary infection with CT and GC. At JMMC, the Roche Cobas Amplicor is employed for the detection of CT and NG by PCR. Acceptable specimens include female endocervical swabs, urine or ThinPrep Pap Test specimens and male urethral swabs or urine specimen.

Genital infection with Chlamydia is the most common bacterial STD in the U.S. and is responsible for about 40% of nongonococcal urethritis in men. In women, genital chlamydial infections are a major cause of pelvic inflammatory disease (PID), which is an important cause of chronic pelvic pain, ectopic pregnancy, and infertility. Perinatal transmission of C.trachomatis to infants can cause neonatal conjunctivitis and pneumonia. Since infections in women and men are asymptomatic, rapid and accurate laboratory diagnosis is important for optimal management of infection in patients and for the interruption of transmission to contacts.

Gonorrhea is an important cause of urethritis in men and cervicitis in women. Approximately 20% to 40% of pelvic inflammatory disease and 14% of tubal infertility can be attributed to gonococcal infections. Additionally, 30-50% of men and women with gonococcal disease are co-infected with C.trachomatis. Therefore, laboratory tests designed to simultaneously detect C.trachomatis and N. gonorrhoeae from a single amplification reaction offer a distinct advantage.

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Influenza (December 2003)


Here are some facts published in Hospital Employee Health - March 2003:

The article recommendations include:

Become proactive. Now is the time to implement a strategy for vaccination!

The most common reason employees are not vaccinated stems from the common misconception that influenza can be acquired as a result. This of course is not possible! So, order your vaccine soon, and develop a strategy to encourage all employees and your elderly patients to get vaccinated!

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Influenza Pandemic (March 2006)

An influenza pandemic is a worldwide outbreak of infection. This occurs when a new influenza A virus subtype emerges that has never circulated among people or has not circulated among people for a long time. No one will have immunity to this virus. To cause a pandemic the new subtype must be able to spread easily from person to person. This is different from seasonal outbreaks that are caused by influenza subtypes that are already in circulation.

There were three pandemics during the 20th century. The 1918-19 Spanish Flu, the 1957-58 Asian Flu, and the 1968-69 Hong Kong Flu . During the Spanish Flu pandemic more than 500,000 people died in the US and more than 50 million people died worldwide. Many people died within a few days after infection and nearly half of those were young healthy adults. The Asian and Hong Kong flu pandemics were caused by viruses containing a combination of genes from human and avian influenza viruses. The Spanish flu virus seemed to have an avian origin.

Scientists believe that there will be another influenza pandemic and that it is only a question of when this will occur. No one knows how severe it will be but even a moderate pandemic could cause 200,000 deaths in the US, and millions more to become sick. Such a pandemic could overwhelm our nation's health care system and cause a severe economic impact. A vaccine would probably not be available in the early stages of a pandemic due to production time. The four different antiviral medications currently available to treat or prevent influenza may not be effective because influenza virus strains can become resistant to them.

The Centers for Disease Control and Prevention and the World Health Organization are monitoring influenza around the world, searching for possible pandemic strains. There is currently a concern about the H5N1 avian influenza causing human infection in Asia. The current mortality rate for human H5N1 infection in Asia is about 50%. Federal, state and local public health organizations are working together to be able to respond effectively to an influenza pandemic.

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A New Resistant Strain of Klebsiella pneumoniae

06/30/2009

This highly drug-resistant pathogen has a 40% mortality rate. Carbapenem-resistant Klebsiella pneumoniae (CRKP) is resistant to almost all available antimicrobial agents. It is currently found primarily in the Northeastern United States but has been found sporadically in 24 states. CDC is very concerned and is recommending an aggressive approach.

All hospitalized patients colonized or infected with carbapenem-resistant Enterobacteriaceae should be placed on contact precautions. There is currently no recommendation when to discontinue contact precautions.

Antibiotic resistance appears to be occurring through a mechanism that can be transferred to other bacteria. Experts fear a possibly fully resistant E. coli 0157 strain as a worst case scenario.

Patients with prolonged hospitalization and invasive devices are at greatest risk. Reported infections include urinary tract infections, bloodstream infections and ventilator-associated pneumonia. Fatalities are due to severity of illness and limited antimicrobial options.

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List Of Reportable Diseases

April 2008

Facilities have a special responsibility to their patients, especially those susceptible to adverse reactions to infection, to practice constant and systematic surveillance for early detection of nosocomial infections and to respond rapidly to contain outbreaks. Outbreaks can be caused by any number of organisms (bacteria, viruses, fungi, parasites) or their toxins. Early recognition of such adverse events followed by an immediate response to reduce their spread is vital. The California Department of Public Health (CDPH) can be of major assist to facilities in the recognition and control of outbreaks of infectious diseases.

While certain diseases are defined by law or public health decree to be reportable (the list for California can be found at http://www.cdph.ca.gov/HealthInfo/Pages/ReportableDiseases.aspx) any "OCCURRENCE of ANY UNUSUAL DISEASE" and "OUTBREAKS OF ANY DISEASE (including diseases not listed in Section 2500)" are reportable to the local public health officer. This means that even if not listed, the disease or event may be reportable if it is rare or the number of cases is beyond what is generally expected (definition of an "outbreak").

Reporting these events to the local Public Health Officer is the mandated duty of "every health care provider" or health facility administrator: all who "may know of a case, a suspected case or an outbreak of diseases within the facility." Certainly, if there is a question as to whether an event should be reported to either public health or one's licensing body, it is always better to ask the agency or Health Officer if they want to know about it, than not report the event at all.

The reportable diseases list was first published in 1945 and has been amended nine times to reflect the changing needs and priorities for Statewide surveillance. In 2004 legislation was signed into law to allow the list to be changed by CDPH in consultation with the California Conference of Local Health Offices (CCLHO), without going through the formal regulatory process.

In 2006 shiga toxin became reportable by both providers and laboratories. The Centers for Disease Control and Prevention (CDC) also recommended that all stool specimens be tested for the toxin. This necessitated a change in the collection of stool specimens: all stool specimens brought to the lab now had to be refrigerated and tested for shiga toxin, even if this test is not specifically requested by the physician.

In 2007 four disease additions were made to Section 2500 (list of diseases): avian influenza, chickenpox hospitalizations and deaths, Cruetzfeldt-Jakob Disease and other transmissible spongiform encephalopathies (TSE), and influenza deaths in persons less than 18 years of age.

More recently, in February 2008, Staphylcoccus aureus was added: "Staphylococcus aureus infection (only a case resulting in death or admission to an intensive care unit of a person who has not been hospitalized or had surgery, dialysis, or residency in a long-term care facility in the past year, and did not have an indwelling catheter or percutaneous medical device at the time of culture.)" See http://www.cdph.ca.gov/HealthInfo/news/Pages/Update%2003-08.aspx. This includes both the methicillin sensitive (MSSA) and methicillin resistant (MRSA) strains. The date as to when this regulation goes into effect has, as of February 2008, not been published.

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Norwalk-Like Viruses (April 2004)


Norwalk-Like Viruses are responsible for causing gastroenteritis outbreaks in many long-term care facilities. The transmission route is fecal-oral. The virus can be spread by food or water but is most frequently spread by the contaminated hands of healthcare workers. Environmental surfaces can also become contaminated, especially in areas where vomiting has suspended viral particles in the air.

The virus is from a family called Caliciviridae. This small virus is extremely infectious requiring only a small number of viral particles to produce symptoms. This virus can survive freezing, and heating to 60C, making it difficult to eliminate from food and water.

The incubation period is 12-48 hours and produces symptoms for 12-60 hours. The symptoms may include nausea, vomiting, abdominal cramps, diarrhea, headache, fever, chills and mylagia. The virus is present in vomitus and stool. Viral shedding begins a few hours before symptoms and may last a week or more even if symptoms are minimal. Immunity does occur after the infection but it will probably only last for six months.

There is no specific therapy available for treatment. The illness is self-limited requiring supportive care occasionally including fluid and electrolyte replacement. Facility outbreaks must be reported to DHS and public health. Control measures must be taken to interrupt the person to person transmission. Outbreaks should be detected early based on symptoms not lab test results.

DHS and some public health departments can provide PCR testing of stools free of charge in outbreak situations. MuirLab can provide stool testing through our reference lab. Specimens need to be obtained during early symptoms and sent fresh. Be sure to follow the lab directions for correct container and refrigeration requirements.

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Novel Influenza A (H1N1) - Laboratory Perspective
Barry Latner, M.D., Medical Director Laboratory Services, John Muir Health

6/30/2009

At the time of this writing, the World Health Organization (WHO) has changed the phase of pandemic alert for the novel Influenza A (H1N1) virus from Phase 5 to Phase 6. This indicates a global pandemic is underway in which there is little or no immunity in the population. While the upgrade designation is an indication to world leaders to implement strategies that reduce the spread, such response has already occurred in our area. It does NOT mean that the virus is more virulent.

The CDC, California Department of Public Health (CDPH) and our local county health services departments have confirmed the widespread incidence of this infection in our community. In the early stages of the outbreak, local county health services and CDPH asked us to test patients with influenza-like illness (ILI) via rapid antigen methods for Influenza A & B, and to forward specimens that tested positive for Influenza A for further speciation testing with real-time PCR. At that time, we were trying to do quick surveillance and identify if and when the novel H1N1 virus would enter the community. Of the 22 rapid test Influenza A positive specimens that the laboratories of John Muir Health forwarded, 21 were confirmed positive for the novel H1N1 Influenza virus (i.e. 95% specificity). As of June 3, 2009 the CDPH reported 1014 total cases of the novel H1N1 Influenza in California (796 confirmed, 218 probable - pending confirmation).

Now that the virus is definitely here, there is no longer a need to test all people with ILI for the novel H1N1 virus, and the practice of referring for confirmation all rapid screen positive Influenza A specimens has been discontinued. However, county health services departments and CDPH are now seeking to determine the severity of disease and how many hospitalizations it is causing. Thus, testing for the novel H1N1 Influenza virus should continue only on people with severe ILI who are hospitalized regardless of rapid test results. For these cases in which further testing for novel H1N1 Influenza virus is required, please notify the John Muir Health laboratory where the specimen was submitted. MuirLab: Microbiology (925) 692-5670; John Muir Med. Center, Walnut Creek Campus: (925) 947-5285 (or ext. 35285); John Muir Med. Center, Concord Campus: (925) 674-2184 (or ext. 22184).

Use of Rapid Influenza Diagnostic Tests: The reliability of rapid influenza diagnostic tests depends largely on the conditions under which they are used. For detection of seasonal influenza virus infection, the sensitivity of the rapid diagnostic test in use at the John Muir Health laboratories ranges from 70% to around 80% and specificity approaches 95%. While it is reasonable to assume that these rapid diagnostic tests can detect novel H1N1 Influenza A in respiratory specimens as nucleoprotein antigens are highly conserved across Influenza A viruses, data are not available on a large scale to determine the sensitivity of the tests for this novel virus. However, our own experience of 95% specificity (see above) is encouraging.

Interpretation of a positive rapid test result: A patient testing positive for Influenza B likely has been infected with seasonal Influenza B virus or is a false-positive result. Such a patient is unlikely to have novel H1N1 virus infection. There are several possibilities when a patient tests positive for Influenza A by rapid antigen test.

Interpretation of a negative rapid test result: Novel H1N1 Influenza virus infection cannot be excluded. Further testing and treatment should be based upon clinical suspicion, severity of illness, and risk for complications. If there is no epidemiologic link to confirmed cases of novel H1N1 infection and the patient has mild illness, further testing and treatment are not recommended.

For further questions or concerns regarding the laboratory aspect of influenza testing, please contact MuirLab Microbiology Supervisor, Janet Long, MS, MT (ASCP) SM at (925) 692-5671, MuirLab Microbiology Medical Director, Nicholas Byrne, MD at (925) 947-5356, or John Muir Health Medical Director of Laboratory Services, Barry Latner, MD at (925) 692-5405. Thank you.

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Pets & Vector Control

In the US West Nile Virus has been identified in over 200 species of birds. Avian influenza tends to favor wild water fowl, dogs, cats, skunks, raccoons, bats, and some other animals can transmit rabies. Though rats are the most frequent carrier, domestic cats are also highly susceptible to plague (Yersinia pestis). In 2005, four pet cats in California were found to have plague. As such, we are reminded that disease vectors are not limited to feral animals.

This year (2006) a healthy 4-year old toy poodle was found to be the carrier of a new epidemic strain of CDAD (Clostridium difficile associated disease). This strain has been implicated in outbreaks of CDAD in hospitals in North America and Europe. It is spreading internationally at an alarming rate, and infecting people who are without the usual risk factors for C difficile. The strain, found in the dog, is classified as ribotype 027, toxinotype III, and possesses genes encoding toxins A, B, and CDT (binary toxin) as well as a deletion in the tcdC gene, which is believed to increase virulence. Infection control investigators became suspicious when outbreaks at several hospitals and nursing homes coincided with the pet's visit.

Such situations highlight the importance of protecting one's clothing (Clostridium difficile can cling to clothes) when handling visiting animals. Careful hand-washing after handling animals is important. Consideration should be given to visiting animals and pets when investigating sources of facility outbreaks.

There are no specific rules or regulations regarding surveillance of infection in facility pets or animal visitors. It is, however, prudent that all pet owners be able to name their animal's veterinarian, attest to the health and immunization status of their animals, and if asked, have the ability to produce documents attesting to this.

Pets, like their human owners, should be protected from common vectors, such as mosquitoes and fleas, and discouraged from approaching sick feral animals. Notify your local public health or animal health agency to remove sick or dead birds and other animals.

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Reducing MRSA (Methicillin-resistant Staphylococcus aureus) Transmission

January 2008

According to an October 2007 report from CDC researchers1, more people in the United States now die from an MRSA infection than from AIDS. About 85% of MRSA infections in 2005 were acquired in the healthcare setting. Those at highest risk for an MRSA infection in the healthcare setting are patients who undergo invasive medical procedures, patients with weakened immune systems and are being treated in hospitals, and patients in nursing homes and dialysis centers. Approximately 15% of invasive MRSA infections were in people with no known health care risk or exposure. Those over age 65 were four times more likely and Blacks twice as likely to get an MRSA infection than the general population. Males were more likely to become infected than females. Those at lowest risk were children over the age of 4 and teenagers.

Transmission of MRSA tend occur in 5 general situations referred to as the 5 C's: Crowding, frequent skin-to-skin Contact, Compromised skin (i.e., cuts or abrasions), Contaminated items and surfaces, and lack of Cleanliness. Healthcare workers' hands are most often cited as the primary means of person to person MRSA transmission. Therefore, basic patient care dictates all healthcare workers wash all surfaces of their hands frequently; when personal protective equipment (PPE), such as gloves, are removed; when the hands become visibly soiled; and after contact with the patient or patient's environment. Gloves, PPE, contaminated bandages and other materials should be discarded in a covered container or a sealed plastic bag. If infectious material is also contaminated with blood, then disposal is according to blood borne pathogen regulations.

Preventing MRSA transmission in the healthcare setting requires a multi-pronged approach.
  1. Good Hand Hygiene: prior to performing a procedure on a patient ask - Am I going to come into contact with any body fluids, blood, open skin, or mucous membranes? If yes, then appropriate PPE should be donned. Use lotion to maintain healthy hands.
  2. Good skin hygiene: patients should be assisted in maintaining clean and intact skin - by bathing or showering several times a week and washing hands frequently. Skin tends to dry and crack in the wintertime. The skin of geriatric and immuno-compromised patients tend to tear and bruise easily.
  3. Dedicated Medical Equipment: if dedicating equipment is not possible, disinfect reusable equipment prior to use on another patient. The necessity of urinary catheters and other devices should be well-considered before placement and removed as soon as possible.
  4. Good Housekeeping should ensure regular and routine cleaning of patient's room; and deep cleaning and disinfection when a patient is discharged or returned to Standard Precautions; and after an outbreak.
  5. Laundry should ensure availability of fresh, clean clothes or gowns for patients' daily wear.
  6. Reservoirs, patients who are colonized or actively infected, should be closely monitored and any potential drainage controlled and covered.
  7. Antibiotic use should be targeted and prudent.

1 See Journal of the American Medical Association 2007;298(15):1763-1771

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Resurgence of Measles

February 2009

In 2008, the United States experienced the largest outbreak of measles since 2001. According to the Centers for Disease Control and Prevention (CDC), the outbreak lasted from January through July, 2008 and affected 131 people, including 14 from California. Eight-nine percent of the cases were imported or associated with importation of measles from other countries. The age of those affected ranged from 5 months to 71 years. Sixteen cases involved infants under 12-months of age and thus were too young for vaccination. One case was presumed immune due to being born before 1957. While none died, 15 were hospitalized, most with pneumonia triggered by measles. Of the 131 cases, 112 (89%) were unvaccinated. Eight cases involved all unvaccinated children within one family in the Seattle area.

Before 1963, when a vaccine was introduced, more than half-a-million people got measles in the US, and 500 died annually. The last major US outbreak occurred from 1989 to 1991, when 55,000 people got measles resulting in 123 deaths. In 2001 there were 116 cases. Due to the success of the vaccination program, measles is no longer endemic in the US and ongoing transmission of the virus was declared eliminated in the US in 2000.

Measles is a highly contagious viral disease and causes fever, cough, rash, and eye irritation. Serious complications include encephalitis, pneumonia, and death. Measles is highly contagious and can be transmitted from 4 days prior to the onset of the rash to 4 days after onset of symptoms. The virus is easily transmitted and can remain active and contagious on infected surfaces for up to 2 hours. Transmission is airborne, through coughing and sneezing and usually occurs in community and health care settings, i.e. child care centers, schools, hospitals, emergency rooms, and physicians' offices. According to the World Health Organization (WHO), measles continues to inflict nearly 18 million people each year, killing an estimated 242,000. Worldwide, 600 children, especially in poor countries, die each day from this very preventable disease.

The Measles Initiative, a partnership led by the American Red Cross, CDC, United Nations Foundation, UNICEF, and WHO, is working to reduce worldwide measles deaths by 90% by 2010.

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Urinary Tract Infections

Urinary tract infections (UTIs) are the most common type of healthcare-associated infection in both the acute and long term care setting. UTIs are the most difficult nosocomial infection to control and eradicate, and contribute substantially to patient morbidity, mortality, healthcare costs, annual doctor visits, and antibiotic use. With advancing age and debilitation the risk for a UTI increases. However, infections in the elderly pose special problems since they are difficult to diagnose due to their atypical presentation or the older person's inability to mount a typical reaction to infection. Rather than presenting the usual symptoms of frequency and dysuria, they may instead demonstrate decreased functional capacity, increased incontinence or number of falls, or worsening mental status.

Women, in particular, are susceptible to UTIs and are also noted to present with atypical symptoms, such as feeling irritable, hot, tired, weak, restless, or, generally unwell. Older women may have additional risks: increased vaginal pH, vaginal atrophy, incomplete bladder emptying or urinary retention, weak pelvic floor muscles, and general debility.

In dealing with UTIs, consider the following: A complete and careful assessment at the start is vital. Treatment of bacteriuria without the accompanying symptoms is NOT recommended. For the elderly treatment of asymptomatic UTIs does not reduce morbidity or mortality.

Discriminate use of antibiotics. Antibiotics are generally NOT recommended for the asymptomatic person despite pyuria or a urine culture suggestive of a UTI.

Diligent hand washing, hygienic practice, and use of aseptic technique are recommended. This may mean more frequent perineal cleansing, showers, or changes of urinary pads or underwear; antibacterial soaps for pericare; softer pads, toilet tissues, or underwear; instruction in or assistance with personal hygiene, e.g. gentle wiping from front to back after toileting; reduction of urinary retention or residual urine by complete and frequent bladder emptying. Urologic consult and treatment may be needed for frequent or recurrent UTIs.

While cloudy or foul-smelling urine does not always necessitate a UTI workup, a workup should be considered if the person has a previous history of UTI. Consider prophylactic cranberry supplements such as juice, capsules, tablets, or dried cranberries.

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West Nile Virus (July 2004)


This virus was first identified in 1937 in the West Nile District in Uganda. It arrived in the US during the summer of 2000. California had two imported human cases in 2002 and several cases in the Los Angeles area in 2003. Dead birds, infected with West Nile Virus, were found in the Los Angeles area in 2004.

This viral infection is spread by mosquitoes primarily to birds, but horses and humans can also be infected. Mosquitoes become infected carriers when they feed on infected birds. A very small number of people have been infected through blood transfusions, organ transplants and breast milk.

Most people who are bitten by a mosquito with West Nile Virus will not get sick. Approximately 20% will get a mild illness including fever, muscle aches, headache, nausea, and vomiting. Approximately 1 in 150 infections will result in severe neurological disease. Encephalitis is more commonly reported than meningitis.

The incubation period for this virus is thought to range from 2 to 14 days, but most typically from 2 to 6 days. Mild cases usually produce symptoms for 3 to 6 days. The most significant risk for developing severe neurological disease is advanced age.

Although West Nile Virus can be transmitted year round in warmer climates, it is most commonly seen in the summer and autumn. Prevention includes using DEET mosquito repellent, the wearing of long sleeve clothing, and avoiding outdoor activity at dusk and dawn. Make sure window screens are in good repair, and drain sources of standing water where mosquitoes may breed and lay their eggs.

Diagnostic testing for West Nile virus can be obtained through local or state health departments for patients with encephalitis or meningitis. The most efficient diagnostic method is detection of IgM antibody to WNV in serum or cerebral spinal fluid collected within 8 days of illness onset using the IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA).

Treatment is supportive often involving hospitalization, IV fluids, respiratory support and prevention of secondary infections.

West Nile virus infection is reportable to both local and state health departments. WNV encephalitis is on the list of designated nationally notifiable arboviral encephalitides.

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