SARS? WNV? For Most, Common Infections are the Real Worry

How concerned do Americans need to be about contracting serious infectious diseases? With regular reports in the media about the spread of West Nile Virus across the US, and more recently of a highly contagious pneumonia-like virus referred to as Severe Acute Respiratory Syndrome, many of us have begun to ask about other infectious diseases as well.

The renewed interest in infectious disease also results from the overwhelming amount of fresh information about and treatments for chronic problems such as diabetes and heart disease. For years, medical communities in developed countries have been able to focus on chronic disease because infectious disease rates had declined sharply due to vaccines, medications, and public health measures protecting food and water.

But with airplane travel a common occurrence and huge numbers of travelers, the world has become a smaller place. Despite our best efforts to keep infections at bay they rarely respect borders, and “exotic” diseases are becoming more common everywhere. Few of us (especially those who only travel to other developed countries and visit regular tourist destinations) have any great chance of acquiring diseases such as West Nile or SARS unless and until their spread becomes much more extensive in our home country. In reality most residents of developed countries have more at risk from the infectious illnesses with which we’re already familiar.

Common Infections a More Likely Threat
The real threats are those we forget to think about; those that invade our homes and healthcare facilities, or sneak up on us during our normal rounds of work and school. Many of these diseases are highly preventable – often with a vaccine or simple sanitary measures – and with a bit of knowledge you can go a long way toward preventing them.

Food- and Water-Borne Infections
By some estimates, contaminated food sickens 76 million Americans every year. Prime causes of food-borne illness include bacteria, parasites and viruses such as E. coli, Salmonella, Listeria, Shigella, Giardia, Cyclospora, Cryptosporidium and hepatitis A virus. These organisms can be found in a wide range of foods and drinks, including meat, milk and other dairy products, spices, chocolate, seafood and even water.

Careless food handling and improper cooking often set the stage for the growth of disease-causing organisms. The key to preventing most cases of these illnesses is very basic: washing your hands, cutlery and counters during preparation, and cooking food well, will help you avoid transmission.

For more information, see 15-Second Procedure Saves Lives (and you already know how to do it), How to Stop Food-Borne Illness Before it Starts, Preventing Hepatitis A Infection While Traveling and E. Coli Outbreaks Becoming More Common in US.

Hepatitis C
Hepatitis C is a liver disease caused by the hepatitis C virus (HCV) that is found in the blood of persons who have the disease. HCV is spread by contact with the blood of an infected person. HCV is a common cause of cirrhosis of the liver, especially in patients who have used recreational drugs by injection, or have had multiple sex partners.

Dr. Mohammad Almoujahed, Assistant Professor of Medicine (Infectious Diseases) at the Medical College of Wisconsin, notes, “There is no vaccine for this infection as of today. Once somebody is infected with this virus, he or she has more than an 80% chance of keeping the virus or having a chronic infection that may progress to cirrhosis and possibly liver cancer.” And, he adds, “The treatment for this infection has a low response rate. The medications can also cause significant side effects and they need to be taken for a long time.” For more information, see Hepatitis C.

Hospital-Acquired Infections
Dr. Almoujahed provides some interesting facts about hospital-acquired infection, otherwise known as nosocomial infection, and several other infectious diseases:

The US Centers for Disease Control and Prevention (CDC) estimates that each year nearly 2 million patients in the United States acquire an infection in the hospital, and about 90,000 of these patients die as a result of their infection. Infections are also a complication of care in other settings including long-term care facilities, clinics and dialysis centers. Dr. Almoujahed reports that those at higher risk for hospital-acquired infection include people in long-term care, patients who undergo multiple procedures, and those who are severely ill. He warns, “Hospital infections continue to thrive due to multiple factors including the increasing number of older patients, patients with chronic diseases and those with weakened immune systems, in addition to the increasing number of invasive diagnostic and therapeutic procedures.”

The CDC reports that about half of all hospital-acquired infections are caused by improper handwashing by staff and/or patients at the hospital. To that end, the organization recently published new hand hygiene guidelines for health care workers, including the use of alcohol-based rubs.

Also at issue in healthcare settings are staph infections caused by bacteria called Staphylococcus aureus. These bacteria can cause serious infections (such as surgical wound infections and pneumonia). In the past, most serious staph bacteria infections were treated with methicillin, a type of antibiotic related to penicillin. Over the past 50 years, however, treatment of these infections has become more difficult because staph bacteria have become resistant to various antibiotics, including the commonly used penicillin-related antibiotics. These resistant bacteria are called methicillin-resistant Staphylococcus aureus, or MRSA.

Health care facilities must continue to be vigilant in regard to avoiding infection. “Every hospital should have a system in place to prevent hospital infections in their patients and employees,” says Dr. Almoujahed. “These measures would benefit the society as a whole because hospital microorganisms that are often antimicrobial-resistant are carried into the community resulting in further spread of infection.” For more information, see Methicillin-Resistant Staphylococcus Aureus.

HIV/AIDS/STDs
The incidence of HIV/AIDS and other sexually-transmitted diseases varies widely around the world, with more cases typically seen among populations with less access to health care and to education about preventive measures. However, even in countries such as the US, where information (and condoms) are widely available, STDs take a huge toll on public health, the economy, and, of course, on those who are infected and those who are close to them.

“AIDS is the leading cause of death in some parts of Africa; it is a threat to the social and political system in that part of the world,” reports Dr. Almoujahed. According to the Joint United Nations Programme on HIV/AIDS, as of the end of 2002, the following statistics tell the story:

• Today, 42 million people are estimated to be living with HIV/AIDS. Of these, 3.2 million are children under 15.
• An estimated 45,000 North Americans acquired the human immunodeficiency virus (HIV) in 2002.
• During 2002, AIDS caused the deaths of an estimated 3.1 million people throughout the world, including 15,000 in North America.
• HIV is increasingly affecting women. Approximately 50%, or 19.2 million, of the 38.6 million adults living with HIV or AIDS worldwide are women.

As far as the treatment of HIV/AIDS, Dr. Almoujahed reports, “Although there are very effective drugs to treat HIV, the number of pills, the life-long treatment, and the side effects of the medications negatively affect the patient compliance, and consequently the treatment of the disease.” But, he emphasizes, treating HIV/AIDS holistically is an important part of proper treatment. “We treat a large number of HIV-infected patients here at the Medical College of Wisconsin Infectious Diseases clinic; we place utmost importance in treating the human spirit as well as the human body; a multi-disciplinary state of the art care is provided to all of our patients.”

For more information, see Choosing the Right Kind of Condom to Prevent STDs and Common Sexually Transmitted Diseases.

Influenza
Every year about 36,000 Americans die due to complications from the flu. Most of these deaths, and the vast number of flu cases, could be avoided by one simple step: vaccination. Those at highest risk for influenza and flu-related complications are:

• Anyone over the age of 50
• Residents of nursing homes and other long term care facilities
• Adults and children over the age of 6 months who have chronic heart or lung conditions including asthma
• Adults and children over the age of 6 months with diabetes, kidney disease, or weakened immune systems due to either treatments for cancer or those with HIV/AIDS
• Children and teenagers on long-term aspirin therapy to prevent Reye Syndrome
• Women who will be more than three months pregnant during the flu season.

For more informationsee, see How Do I Know It’s the Flu? and Season Has Started, But Flu Shot Still a Good Idea.

Meningitis
According to the CDC, meningitis can be caused by a viral or a bacterial infection. Knowing whether meningitis is caused by a virus or bacterium is important because the severity of illness and the treatment differ. Viral meningitis is generally less severe and resolves without specific treatment, while bacterial meningitis can be quite severe and may result in brain damage, hearing loss, or learning disability. Some strains can even be fatal. For bacterial meningitis, it is also important to know which type of bacteria is causing the meningitis because antibiotics can prevent some types from spreading and infecting other people.

“The most important issue in meningitis is early recognition of this infection and early initiation of antibiotics,” asserts Dr. Almoujahed. “That can significantly improve the outcome and prevent death.” He continues, “Any individual with fever, headache and neck stiffness should seek medical attention by calling their health care provider or going to the Emergency Room; in cases of meningitis, timing of receiving medical care is of utmost importance in determining the long-term outcome of the patient.” In addition, all household members of patients known to have meningitis should contact their health care provider to see if a preventive antibiotic is needed to stop them from getting the same infection. For more information, see Viral Meningitis.

Tuberculosis
Although the number of tuberculosis cases in the United States has vastly decreased since drugs to treat it became available in the 1940s, this is not the case worldwide. “Tuberculosis is still the number one infectious disease killer in the world,” says Dr. Almoujahed. “One-third of all human beings are infected, and more than 3 million die each year from this infection.” Treatments that are widely available in developed countries are difficult to obtain and implement in other parts of the world. “We do not have a fully effective vaccine for this infection yet, and the medications that we give must be given for a long time to be curative,” reports Dr. Almoujahed. For more information, see Tuberculosis.

Familiar Infections, Huge Impact
Information about the infectious diseases with which we're already familiar can sound so familiar as to seem ordinary. But their toll on the public health and personal lives of Americans is anything but ordinary. These diseases not only affect us on an individual level, they also have devastating effects on our health system and economy.

And what about the mysterious, pneumonia-like illness currently spreading through several areas of the world?

SARS
Severe Acute Respiratory Syndrome, or SARS, had infected fewer than 1,500 people (with 53 deaths) as of March 28, 2003, according World Health Organization statistics. Health investigators first looked at a family of viruses called paramyxovirus as a possible cause of the infection, but more recent reports from the Centers for Disease Control and Prevention (CDC) have focused on a group called the coronaviruses, which are related to the common cold. There is still very little information as to definite causes and treatments of the illness.

Additional steps needed to confirm this hypothesis include further culturing of the virus from appropriate specimens, sequencing the viral genome, and examining specimens from patients at different stages of their illness.

“This collaboration among scientists led by the World Health Organization (WHO) is unprecedented,” said CDC Director Dr. Julie Gerberding. “We certainly have more work to do, but we think we are on the right track. And our systems to identify cases and investigate them are working too, thanks to all the frontline clinicians and state and local health departments around the country.”

Do we need to worry? That depends on whether the illness continues to jump borders before we can find a way to stop it. At this point, the vast majority of cases have occurred in Guangdong in the Peoples' Republic of China; Hanoi, Vietnam; Hong Kong or Singapore. Officials are on the lookout for people with a rapid onset of high fever (>100.4 degrees) and clinical findings of respiratory illness including cough, shortness of breath, difficulty breathing; or with a diagnosis of pneumonia or acute respiratory distress syndrome. Even though there have been only 39 reported cases of SARS in the United States (with no deaths), it’s still best to see your physician as soon as possible if you have any of these symptoms.

You should also see a doctor if you have recently traveled out of the country to areas with suspected or documented community transmission of SARS, or have recently had close contact with anyone who has recently traveled to a SARS area and acquired a respiratory illness.

This article includes information from:
US Centers for Disease Control and prevention (CDC)
Joint United Nations Programme on HIV/AIDS
World Health Organization (WHO)

MCW Health News presents up-to-date information on patient care and medical research by the physicians of the Medical College of Wisconsin.