By Cat Troiano

With summer just around the corner, outdoor recreation beckons. While sun, surf and communing with nature provide enjoyment throughout the warmer months, the season also presents ticks, which pose serious health risks that can compromise quality of life. When we think about diseases that are spread via bites from ticks, Lyme disease typically comes to mind. While Lyme disease is the most commonly diagnosed tick-borne illness, these parasitic arachnids transmit a lengthy list of other maladies as well. Many of these illnesses present with similar signs and symptoms, which is why testing is important for attaining a diagnosis.

How Are Tick-Borne Illnesses Spread?

Once hosts, such as mice, deer, dogs and sheep, become infected, they harbor the disease pathogens. Depending on which tick-borne disease is infecting the host, such pathogens may be viral, bacterial or protozoan in nature. Some tick-borne diseases are rickettsial, meaning that they are caused by rickettsia, which are microorganisms that possess qualities of both viruses and bacteria. Rickettsia cannot thrive and reproduce outside of living cells.

Ticks are parasitic organisms. Once a tick feeds off of the blood from an infected host, the tick becomes a vector. The contracted pathogen is then carried by the tick and transferred into the next host off which it feeds.

What Are the Most Common Tick-Borne Illnesses?

According to the Centers for Disease Control and Prevention, the number of confirmed and probable cases of Lyme disease exceeded 42,000 in 2017 and remains the most frequently reported tick-borne illness in the United States. Lyme disease is transmitted by the black-legged leg, which is commonly known as the deer tick, throughout the northeast, northern Midwest and mid-Atlantic states. It is also transmitted by the western black-legged tick in northern California and up the Pacific coast. You can read more about Lyme disease and its test interpretations here. Additional tick-borne illnesses, their vectors and geographic prevalence include:

Rickettsial Diseases:

• Anaplasmosis, transmitted by the black-legged tick in the northeastern and northern midwestern regions and by the Western black-legged tick in northern California and along the Pacific coast
• Ehrlichiosis, transmitted by the Lone Star tick throughout the eastern states and by the American dog tick along the Pacific coast and in areas east of the Rocky Mountains.
• Rocky Mountain spotted fever, transmitted by the American dog tick east of the Rocky Mountains and along the Pacific coast
• Rickettsia parkeri rickettsiosis, transmitted by the Rocky Mountain wood tick throughout the Rocky Mountain region

Non-rickettsial Diseases:

• Babesiosis, transmitted by the black-legged tick in the northeastern and northern midwestern regions and by the Western black-legged tick in northern California and along the Pacific coast
• Tularemia, transmitted by the Lone Star tick throughout the eastern states, by the Rocky Mountain wood tick throughout the Rocky Mountain region and by the American dog tick along the Pacific coast and in areas east of the Rocky Mountains
• Powassan virus, transmitted by the black-legged tick in the northeast as well as in the states of Virginia and Wisconsin
• Borrelia miyamotoi disease, transmitted by the black-legged tick in the northeastern and northern midwestern regions and by the Western black-legged tick in northern California and along the Pacific coast
• Tick-borne relapsing fever, transmitted by the orinthodoros soft tick in the western states
• Colorado tick fever, transmitted by the Rocky Mountain wood tick throughout the Rocky Mountain region
• Heartland virus, transmitted by the Lone Star tick in midwestern and southern states

Some ticks can harbor multiple diseases, and coinfection from one tick bite is a possibility. It is also important to note that some of these illnesses can be contracted internationally, and a number of additional tick-borne diseases have been identified in other nations. Novel tick-borne illnesses can also emerge, such as the recently identified Long Island tick rhabdovirus, which is transmitted by the ambloyomma americanum tick, and 364D rickettsiosis, transmitted by the Pacific Coast tick and recently discovered in the state of California.

Signs of Tick-Borne Illnesses

The signs and symptoms of many tick-borne illnesses are not unique to these illnesses, and they present with most of the tick-borne diseases. These influenza-like symptoms typically include:

• Fever
• Headache
• Muscle aches
• Joint pain
• General malaise

Some illnesses may progress with the presentation of symptoms of serious complications, such as neurological deficits, kidney or liver failure, or compromised cardiorespiratory function. Some diseases, such as Lyme disease, may present with a characteristic rash, but it is crucial to note that these rashes do not emerge on all infected patients.

On the rise in recent years is the incidence of red meat allergies caused by the bite of the Lone Star tick. Galactose is a monosaccharide, a simple sugar that is found in some foods, often in combination with glucose to form the disaccharide lactose. However, the Lone Star tick produces another galactose compound known as galactose-alpha-1,3-1 galactose, or alpha-gal, in its gastrointestinal tract. When the tick bites its host, this sugar is injected, and it renders the host allergic to red meats. This condition is known as alpha-gal syndrome. Some affected individuals will suffer from anaphylactic shock after consuming beef, pork, lamb and other red meats, and the reaction may occur three to six hours after they have eaten the red meat. 

Another tick-borne condition is tick paralysis, a rare phenomenon that primarily affects children. Tick paralysis is transmitted by various tick species, including the American dog tick, and it results when a biting tick deposits a neurotoxin into its host. Signs of tick paralysis include flaccid weakness, changes in voice, respiratory difficulty and neurological symptoms of paralysis ascend up the body from the lower extremities. Unlike other tick-borne illnesses, the condition typically resolves rapidly and completely once the infected tick is extricated from the host, but if the tick is not discovered and the condition continues to progress, respiratory failure and death can result.

So many diseases and symptoms! How are physicians to make specific diagnoses under these conditions? Laboratory tests are available for detecting antibodies for several of the most common tick-borne illnesses.

Diagnostic Testing

Laboratory testing to identify a particular tick-borne disease should be pursued for any patient who presents with these symptoms and meets any one of the following criteria that increases his or her risk for exposure:

• The patient found a tick attached on their body.
• The patient resides in a geographic location in which any tick-borne disease(s) is prevalent.
• The patient has recently traveled to a geographic location where tick-borne illnesses are prevalent.
• The patient has recently spent time in an area where ticks are endemic – i.e. camping in a wooded area.

Abnormal laboratory findings on a complete blood count in a patient with tick-borne illness may include low hematocrit, platelet and white blood cell counts and an elevated reticulocyte count. Abnormal findings on a metabolic profile may include elevated liver enzymes and elevated renal values, which include creatinine and blood urea nitrogen levels. Elevated protein may be detected on a urinalysis.

In addition to ordering a complete blood count and metabolic profile, there are numerous individual laboratory tests available to diagnose particular suspected tick-borne diseases. Depending on the test that is selected, diagnosis is achieved through the following various methods:

• Microscopic visualization and identification of the pathogen in blood cells
• Enzyme-linked immunosorbent assay (ELISA) to detect specific antibodies
• Immunofluorescent assay (IFA) to detect particular IgG or IgM antibodies
• Polymerase chain reaction to identify pathogen DNA
• Immunoblot technique, such as the Western blot test
• Culture to identify bacterial pathogens

The newest addition to the arsenal of tests for diagnosing tick-borne diseases is the TBD Serochip, which is a real-time polymerase chain reaction method screening. The advantage of this particular test is that it evaluates one blood sample to detect antibodies of eight of the most common tick-borne pathogens found in the United States. This alone makes this test valuable in that it can pinpoint a specific infection when generalized symptoms might otherwise require multiple individual tests, and it also has the capability to identify coinfections. The eight diseases that can be diagnosed with this test include Lyme disease, anaplasmosis, babesiosis, ehrlichiosis, Rocky Mountain spotted fever, Heartland virus, Powassan virus and borrelia miyamotoi.

An alpha-gal IgE test is available for determining if a patient who has suffered an allergic reaction after consuming red meat has contracted alpha-gal syndrome.

There is no laboratory test for tick paralysis. However, if a patient presents with symptoms, physicians should seek out a tick that is attached on the patient as well as order testing to rule out Guillain-Barre syndrome, an autoimmune disorder that presents with similar signs, including paralysis.

Treatment and Prevention

Tick-borne diseases, some of which can progress rapidly, should be treated as early as possible in symptomatic patients, which often means administering treatment even before test results become available. Most tick-borne diseases are treated with antibiotic therapy, typically with doxycycline or tetracycline.

There is no treatment for alpha-gal syndrome, and patients are strongly advised to avoid all red meat and food products containing meat-based ingredients. In some cases, allergy symptoms can abate over time if the patient does not sustain another bite from a tick that injects alpha-gal.

To reduce the risk of contracting tick-borne diseases, patients should be advised to take preventative measures, which includes adopting the following practices:

• When venturing outdoors where there is an inherent risk of exposure to ticks, don light-colored clothing so that ticks are easy to spot, and wear long sleeves and pants. Tucking the bottoms of the pant legs into white socks will help to prevent ticks from migrating to the legs, and they will be easy to find on white socks.
• Apply a tick repellent spray that contains DEET to both outer clothing and exposed skin.
• Campers should spray the outer surfaces of tents and other gear with insecticidal products that contain permethrin.
• When hiking, remain on cleared trails, and avoid straying off course into areas with tall grasses, brush and weeds.
• Pet owners should apply topical tick preventative products as prescribed by their veterinarians to dogs and to cats that go outdoors.
• Clothing should be stripped immediately upon returning indoors and placed directly into the dryer for 10 minutes to kill any ticks that were missed when inspecting the apparel. Patients should then shower and wash their hair, and conduct a thorough inspection of their skin from head to toe, removing any ticks immediately.
• Outdoor home property should be maintained and kept free of all brush and debris to eliminate areas that small wild animals, the primary hosts for ticks, may find hospitable. Trees, lawns and shrubs should be sprayed regularly with insecticide products.

To help physicians to rule out some of the tick-borne disease possibilities, patients should be advised to deposit any ticks that they extricate from their bodies into a sealed jar or a Ziploc bag. If symptoms of illness develop, bringing the tick along to the doctor’s appointment can facilitate a visual identification of the tick, which helps to guide in antibiotic and test selection for more timely success with treatment.

By Cat Troiano

Calcium is one of the seven macrominerals found in the human body. All minerals are crucial for carrying out a variety of functions to sustain human life. Calcium is not produced in the body, and so this important micronutrient must be consumed through diet. Calcium is the building block for bone and tooth formation. Bones contain 99 percent of the body’s calcium. The remaining small percentage carries out additional critical functions, including:

• Works together with vitamin K to aid in blood coagulation
• Regulates heartbeat rhythms
• Enables vasoconstriction and vasodilation to stabilize blood pressure
• Maintains permeability and stability of cell membranes to enable cellular communication
• Aids in neurotransmission
• Enables the binding of muscle fiber proteins to facilitate muscle contraction

That’s a lot of jobs for only one percent! If there is an insufficient amount of calcium on board to carry out these vital roles, then the parathyroid glands come to the rescue. These four glands that neighbor the thyroid gland release an increased amount of parathyroid hormone (PTH) when low blood calcium levels are detected, prompting the bones to release calcium into the blood. PTH also stimulates the production of calcitriol, an inactive form of vitamin D, to facilitate increased dietary calcium absorption in the gastrointestinal tract. PTH also acts on the kidneys to prevent the filtration of calcium for elimination and instead encourage reabsorption of calcium back into the blood.

Conversely, when blood calcium levels are too high, the parathyroid gland produces a lower amount of PTH, and the thyroid gland kicks in to release calcitonin, a hormone that reduces blood calcium levels by reducing the breakdown of bone. Throughout life, bone continuously breaks down and rebuilds, a normal process called remodeling. The human skeleton is almost entirely rebuilt over the course of every 10 years. Remodeling enables the removal of calcium from bone when blood calcium levels are deficient or when the need for increased blood calcium arises, such as during pregnancy and lactation. PTH stimulates specialized bone cells called osteoblasts to build bone tissue. PTH, as well as calcitonin, can also inhibit osteoclasts, the bone cells that break down bone tissue.

Maintaining an ideal calcium level for optimal physiological function is a balancing act that the body must perform. Testing blood calcium levels is essential so that abnormal levels can be addressed to restore proper function.

Calcium Tests

There are two presentations of calcium in the blood. Free calcium, also called ionized calcium, is calcium which is not bound to organic molecules. Bound calcium is that which is bound to molecules, predominantly to the protein albumin and, in smaller proportions, to immunoglobulins and to phosphorus.

The body’s ability to utilize a mineral depends on the mineral’s bioavailability. Once a mineral is bound, it is no longer bioavailable. Free calcium is the more active form of calcium with a higher bioavailability, and bound calcium accounts for roughly 40 percent of blood calcium. Therefore, total calcium is considered to be a mineral that is of medium bioavailability.

Tests that evaluate blood calcium levels include the following:

Total calcium test – evaluates levels of both free and bound calcium. The normal reference range for an adult is a total blood calcium level of 8.5 to 10.3 mg/dL.

Ioniozed calcium test– evaluates the blood calcium level of free calcium only. The normal reference range for an adult is an ionized calcium level greater than 4.6 mg/dL.

Total calcium levels are also typically included in both the comprehensive metabolic panel and the basic metabolic panel.

When the body has an excess surplus of calcium, some of that excess is eliminated through urination. The urinary Ca+2 test evaluates the amount of calcium that has been passed in all of a patient’s urine that has been excreted over 24 hours. The normal reference range for urinary Ca+2 is 100 to 300 mg per 24 hours.

Fasting is not necessary for calcium level testing, but patients should be instructed to refrain from taking any medications or supplements that can affect calcium levels, including anticonvulsant drugs, diuretics, bisphosphonates, corticosteroids, lithium, estrogen, calcium supplements and vitamin D supplements.

Patients for whom calcium level testing should be ordered include those with:

• Kidney disease
• Thyroid disease
• Osteoporosis
• Neurological deficits
• Liver disease
• Pancreatitis
• Malabsorption
• Abnormal EKG

Ionized calcium levels should be monitored in patients who have cancer, who are critically ill and receiving intravenous fluid therapy, who are receiving blood transfusions and who have abnormal albumin levels on their metabolic panels.

What Does a Low Calcium Level Indicate?

Hypocalcemia is defined as an abnormally low calcium level. This can result when too much calcium is eliminated through urination or when an insufficient amount of calcium is released from bone into the blood. Causes of hypocalcemia include the following:

• Underactive parathyroid gland
• Low blood protein levels
• Low magnesium levels
• Low vitamin D level
• High phosphorus level
• Kidney failure
• Pancreatitis
• Dietary calcium deficiency
• Use of certain drugs, including bisphosphonates, corticosteroids, calcitonin, anticonvulsants, such as phenobarbitol, and certain antibiotics, such as plicamysin and rifampin
• Dietary calcium deficiency                

Initially, patients with moderately low calcium levels may be asymptomatic. Severely low or prolonged low calcium levels can result in symptoms that include arrhythmias, tingling in the hands or feet, muscle spasms, muscle cramping, confusion, memory loss, hallucinations and seizure activity.

Hypocalcemia can usually be corrected with the use of calcium supplements, and vitamin D supplementation may be recommended as well. Treatment for the underlying cause of low calcium levels must also be recommended.

What Does an Elevated Calcium Level Indicate?

Hypercalcemia, the opposite of hypocalcemia, is defined as an abnormally high calcium level. Causes of hypercalcemia include the following:

• Overactive parathyroid glands
• Hyperthyroidism
• Cancer, including lung cancer, breast cancer, blood cancers and cancers that have metastasized to the bones
• Tuberculosis
• HIV/AIDS
• Sarcoidosis
• Paget disease
• Certain drugs, including lithium prescribed for the treatment of bipolar disorder, diuretics prescribed for the treatment of hypertension and heart failure, and antacids
• Excessive intake of calcium and/or vitamin D supplements over an extended duration
• Extreme dehydration
• Patient inactivity

As in the case of hypocalcemia, mild hypercalcemia may present no apparent symptoms. Patients with more severe or advanced cases of hypercalcemia experience increases in water intake and urinary output, kidney stones, nausea, vomiting, constipation, abdominal pain, decreased appetite, bone pain, muscle weakness, fatigue, depression, syncope, arrhythmia and coma.

Drug therapy is typically the course of treatment for hypercalcemia. The drugs that are prescribed are dependent on the cause of the high calcium levels. Commonly used drugs include biphosphonates, calcitonin and corticosteroids.

Depending on the abnormal calcium level test result, additional screenings may be ordered, such as thoracic diagnostic imaging, thyroid and parathyroid hormone levels, phosphorus level, vitamin D level and a renal function panel.

How Much Calcium Should Be Taken In?

Since calcium must be consumed, patients should be educated as to how much calcium they should be taking in. Female patients are especially concerned, knowing that as their age advances and their estrogen hormone levels decline sharply during menopause, the body’s bone formation capability is less able to keep up with the breaking down of bone, resulting in lower bone mass density. This condition, known as osteoporosis, results in brittle bones than fracture easily and can render a patient physically impaired, threatening their independence and quality of life.

According to the National Osteoporosis Foundation, healthy adults should strive to take in 1,000 mg of calcium daily. That amount should be increased to 1,200 mg daily for women older than 50 and for men older than 70 years of age. Foods that contain calcium include, but are not limited to, milk, yogurt, cheese, egg yolks, almonds, soybeans, edamame, tofu, sardines and leafy greens, such as spinach, kale and bok choy.

Remember that calcium cannot be absorbed without the help of vitamin D. Only three vitamins can be produced by the human body, and although vitamin D is one of the three, in addition to vitamin K and biotin, it is only produced when a patient’s skin receives adequate sunlight exposure. Healthy adults should take in 5µg of vitamin D daily. Wild-caught tuna and salmon are among the few foods that naturally contain vitamin D, but many cereals, dairy products and orange juices are fortified with vitamin D and, in some cases, with calcium as well.

As described above, you can have too much of a good thing. All patients should have their calcium levels checked and their overall metabolic health evaluated prior to consulting with their physicians about calcium supplementation.

By Cat Troiano

It’s that time of year. Schools, office buildings and other crowded public spaces are teeming with pathogens, from the common cold and influenza viruses to bacterial pneumonia and strep throat. Testing select patients who present with a sore throat provides the definitive diagnosis of strep throat so that effective treatment can be prescribed.

Sore Throat Is Not Always Strep Throat

The symptom of a sore throat can arise from irritants in the environment, inhalant allergies, acid reflux, postnasal drip, a fungal infection, a cold or a bacterial infection. A typical sore throat that often accompanies the onset of a cold is not the same as streptococcal pharyngitis, which is better known as strep throat. Strep throat is an infection caused by group A streptococci bacterium. A patient who has a cold-related sore throat typically experiences other upper respiratory symptoms as well, such as coughing, nasal congestion, chest congestion and a runny nose. These symptoms do not accompany strep throat. Symptoms that do commonly go hand in hand with strep throat include the following:

• High fever, typically 101 degrees Fahrenheit or greater
• Chills
• Headache
• Redness of the throat and on the hard and/or soft palate
• Dark red spots in the mouth, on the palate or on the throat
• White or yellow patches on the tonsils
• Swollen tonsils
• Swollen lymph nodes in the neck
• Pain or difficulty when swallowing
• Loss of appetite
• Nausea
• Muscle aches
• Lethargy
• Sandpaper-like skin rash that is pink in color

Children and teens aged 5 to 15 are the most typically affected, with nearly 30 percent of patients of this age group presenting with sore throats being diagnosed cases of strep throat, compared to only an average of 10 percent of adults with sore throats. Kids are taught to share, and they aren’t shy about sharing germs! However, adults who are frequently exposed to children, such as day care workers and schoolteachers, as well as parents of children who have the infection, are also at risk. Strep throat is contagious, and the incubation period is two to five days post exposure. Strep infection is rare in children less than three years of age.

Any patient who presents with a sore throat that began quickly and persists for a week, or with a sore throat combined with a fever along with any of the additional symptoms that may be indicative of strep throat, should be tested so that proper treatment can be initiated.

Swab for Strep

There are two ways to test for group A streptococci. One test, the rapid streptococci screening test, yields results quickly. This immunoassay test identifies the presence of group A streptococci antigen in a sample of mucous that has been taken from a pharyngeal swab, and it generates a positive or negative result in approximately 5 to 10 minutes. A positive result can facilitate confident on-site diagnosis and prompt initiation of effective treatment.

The second way to test for strep is the traditional microbial culture method. Like the rapid strep test, the culture test requires a sample that has been swabbed from the back of the throat. Although culturing a sample has a high level of accuracy due to high sensitivity and specificity, the test can take 48 hours to generate results. Since a culture can generate more accurate results than the rapid strep testing, this method is recommended to confirm negative rapid strep test results from symptomatic patients as well as to rule out other infections. In addition to group A streptococci, the throat culture test also detects the presence of pathogens that cause such conditions as bacterial pneumonia, meningitis and pertussis.

It is important to note that patient use of antiseptic mouthwash products as well as recent antibiotic therapy can alter the results of rapid strep tests and throat culture tests.

Some patients may be carriers of group A streptococci, which simply means that such individuals may harbor the bacteria without having an active infection. Carriers will have positive results on their tests, even if their sore throats are caused by other pathogens. Patients who are otherwise asymptomatic and test positive for strep throat typically do not require treatment, as carriers are much less likely to develop complications that can arise from failure to treat strep infections, and their probability of spreading the bacteria to others is lower.

Treatment and Prevention

While sore throats that present with viral infections, which do not respond to antibiotic drugs, typically resolve without treatment, it is essential to treat strep throat promptly. Failure to treat a strep infection places the patient at risk for serious complications. One such complication is rheumatic fever, a life-threatening inflammatory condition that affects the joints and can also ultimately result in congestive heart failure. Another potential complication is poststreptococcal glomerulonephritis, which is an inflammation of the glomeruli – the filtration structures of the kidneys – that can lead to kidney disease and renal failure. Other complications include ear infections, sinus infections, abscesses on the tonsils, scarlet fever and mastoiditis, which is an inflammation of the mastoid process, which is the lower portion of the temporal bone of the skull.

Once the rapid strep test issues a positive result, antibiotic therapy is prescribed for a period of 5 to 14 days, depending on which antibiotic drug is used. Patients should stay home from school or work until at least 24 hours after the antibiotic treatment has begun and the fever is gone. It is imperative that patients complete the entire prescribed course of antibiotic treatment, even once symptoms improve, in order to ensure that the infection is completely resolved. Antibiotic treatment will prevent the aforementioned complications that can arise from an untreated strep infection, decrease the symptoms, shorten the duration of illness and reduce the spread of infection to others.

Group A streptococci is spread through contact with droplets from infected patients who sneeze or cough. When someone touches a contaminated surface and proceeds to touch his or her eyes, nose or mouth, he or she can contract the infection. Patients should cover their mouth with a tissue if they sneeze, and everyone should refrain from sharing drinking glasses, cups and bottles as well as dining utensils. Everyone should also be extra diligent with washing their hands frequently throughout the school year, which also tends to coincide with the flu season.

Since some of the symptoms of strep throat and those of the influenza virus are similar, a rapid influenza test may be ordered along with the rapid strep test for a more thorough and definitive diagnosis. Testing is a crucial part of ensuring a proper diagnosis so that ineffective treatments can be avoided and the development of patient antibiotic resistances can thus be prevented.

By Cat Troiano

This year’s flu season is well underway, normally peaking during the months of December through February. Over the course of the 2017-2018 season, there were 185 influenza-related pediatric deaths, and more than 30,000 individuals in the United States were hospitalized due to influenza. A number of diagnostic tests are now available for helping to diagnose influenza patients, and some of these tests can achieve an earlier diagnosis for more prompt initiation of treatment. This, in turn, can help to reduce the mortality rate and the number of hospitalizations that result when complications of the virus set in.

A Few Flu Facts

Influenza, commonly referred to as the flu, is a contagious and potentially serious viral respiratory infection that is transmitted through aerosolized droplets and surface contact.
While there is some overlap in many of the symptoms of the flu and those of a cold, one distinction between the two is the sudden onset of the flu when it strikes, unlike a cold’s gradual presentation. Another distinction is that most, but not all, patients who have the flu will run a fever and experience chills. Other symptoms of the flu include:

• Muscle aches
• Headaches
• Cough
• Chest discomfort
• Lethargy
• Sore throat
• Nasal congestion or nasal discharge

Vomiting and diarrhea can also present in some influenza cases, especially in pediatric patients.

While the majority of patients recover from the flu without additional misery, the illness can pose further complications to some individuals, including:

• Pediatric patients under the age of five years
• Senior patients aged 65 years or older
• Pregnant women
• Residents of long-term care facilities
• Patients with obesity
• Patients with compromised immune systems, such as those with cancer, HIV or AIDS
• Patients who suffer from any of a number of chronic conditions, including asthma, diabetes, coronary artery disease or cardiorespiratory disease

Some of the complications that can result from influenza include sinus infections, bronchitis and pneumonia, which can be fatal in these high-risk patients.

A Virus by Any Other Name

There are two types of flu viruses, which are known as influenza A and influenza B, that are the common culprits for flu outbreaks among the human population each season. However, there are numerous subtypes of influenza A, each identified by its specific protein makeup. Two proteins that are analyzed to identify these subtypes are hemagglutinin and neuraminidase. To date, subtypes H1 through H18 as well as N1 through N11 have been identified. H1N1 and H3N2 are the most prevalent subtypes of influenza A that are currently affecting human patients.

There are also influenza types C and D. Influenza C typically causes a much milder respiratory infection and is not believed to lead to an epidemic. Influenza D is infects cattle and is not known to pose a health threat to humans.

Influenza A and B viruses mutate into new strains through processes known as antigenic drift, which is a slower and more gradual process, and antigenic shift, which takes place more abruptly. In both antigenic drifts and antigenic shifts, the genetic material of the virus undergoes changes when the virus replicates. It is the evaluation influenza antigenic properties that enables the identification of presently circulating flu virus strains and then guides in the formulation of influenza vaccine to be administered for combating the flu during the following season. The results of influenza testing can also provide this valuable data.

Timely Influenza Tests

If a patient presents with the aforementioned flu symptoms, performing an influenza test can serve four purposes:

• Rule out other illnesses than may be causing the symptoms
• Enable the proper flu treatment sooner if the test is positive or avoid unnecessary drug therapy if the patient is negative
• Guide the physician toward the safest course of recommended treatment for patients who are high-risk individuals for developing complications
• Keep tabs on the potential for localized outbreaks of a flu virus in order to prompt recommendations for preventative measures

There are several influenza tests available. Traditional culturing and other tests can take hours to days to generate results. However, there are two tests that can be performed onsite which generate results in minutes.

The rapid influenza diagnostic test is an antigen detection test. The test is able to screen for influenza in a specimen taken from a nasopharyngeal, nasal or throat swab or aspirate. The rapid influenza detection test provides positive or negative results in as little as 15 minutes. Depending upon the specific test that is used, some rapid influenza diagnostic tests can detect both influenza types A and B.

The rapid molecular assay test detects the presence of influenza RNA, or nucleic acid. This test analyzes a specimen from a nasopharyngeal or nasal swab for influenza types A and B, providing a positive or negative result in 15 to 30 minutes.

One drawback of the rapid influenza diagnostic test is a high incidence (30 to 50%) of false-negative results. However, if a symptomatic patient’s test generates a negative result and his or her primary care physician strongly suspects influenza as the cause of the symptoms, the Center for Disease Control and Prevention (CDC) advises initiating flu treatment while pursuing a second test, either through the more sensitive and specific rapid molecular assay test or a viral culture test, for confirmation of the illness.

It should be noted that a patient who received the live attenuated influenza vaccine within the previous seven days are likely to receive a positive result on a rapid influenza diagnostic test, even if they are not contagious with the influenza virus. Depending on which rapid influenza diagnostic test is used, some will detect the vaccine strains for even longer than seven days.

For the most accurate results, patients should be tested within three to four days of the onset of their symptoms. Patients who can be treated for the flu with anti-viral drug therapy will gain the greatest benefits, including a shorter duration of the illness, a reduction in the severity of their symptoms and a reduced chance of developing complications, when treatment is begun early in their illness.

Prevention Through Vaccination

The first proactive step toward flu prevention is for patients to be vaccinated against the seasonal flu virus. The CDC recommends that every individual six months of age and older should receive the influenza vaccine. Several variations of the vaccine are available to accommodate different age groups and patient health needs for maximum safety and efficacy. Influenza vaccines are tailored each year to combat recent active strains of the illness. Therefore, everyone must be inoculated annually. Pregnant women are more prone to serious illness as a result of contracting the flu virus, and the flu places their unborn baby at risk for premature labor and delivery. The flu vaccine offers protection for the pregnant women and for their developing fetuses.

Additional Preventative Measures

In addition to vaccination, physicians should advise patients to practice the following habits to enhance their immune system’s ability to fight off the flu virus:

• Wash hands often and thoroughly.
• Refrain from close personal contact with anyone who has the flu.
• Avoid interacting with someone who has the flu as much as possible.
• Continue to eat a nutritionally balanced diet, and engage in regular physical fitness routines.
• Keep stress levels to a minimum, and get plenty of sleep.

Reduce the Spread

Anyone who contracts the influenza virus should stay home from work or school to avoid spreading the illness to others. These additional measures should be followed to reduce contamination and spread:

• Patients should cover their nose and mouth with tissues when they cough and sneeze.
• Patients should refrain from close personal contact with others.
• Patients should avoid touching their nose, mouth or eyes. Doing so and then touching other surfaces spreads the germs.
• To reduce the viability of aerosolized flu viruses, maintain a relative humidity level of 40 percent or higher in the home. The higher the air humidity is, the lower the chances are that the flu virus will thrive. This is why flu season peaks during the colder months of low climatic humidity and increased dryness in the air that results from indoor heating systems.
• Use a disinfectant that has been approved by the Environmental Protection Agency as being effective at killing the influenza virus to wipe down countertops and frequently handled objects, including doorknobs, remote controls, keys and key fobs, faucet handles, toilet flush handles, light switches, tablets, phones, door handles, desktop computer keyboards and control panels on refrigerators, microwaves and coffee machines, etc.

According to the CDC, the influenza virus infects 5 to 20 percent of the United States population each season, and up to 200,000 individuals are admitted annually to hospitals as a result of its complications. A combination of preventative measures and early testing of symptomatic patients can reduce that number of hospitalizations as well as the flu’s severity and duration.