The administration of influenza vac...

The administration of influenza vaccine to appropriate risk assemblages remains a high priority for family physicians. Nevertheless, from late fall between the sides of early spring of every year, family physicians must distinguish among the many marks of "common cold" viruses, bacteria, and influenza viruses that cause respiratory tract symptoms. The diagnostic and treatment challenge may be difficult because all of these pathogens can cause nonspecific respiratory and somatic symptoms.

In the clinical setting, rapid, accurate diagnosis of influenza is based onward the history, physical examination and, in a certain number of instances, laboratory testing before treatment is initiated. This article reviews the clinical diagnosis of influenza and provides information about rapid in-office diagnostic tests

Clinical Course of Uncomplicated Influenza

greatest in quantity physicians use a cluster of signs and symptoms to diagnose influenza. Influenza viruses, general cold viruses, and bacteria cause similar upper respiratory tract symptoms, on the contrary the intensity, severity, and oftenness of the symptoms vary. Features of influenza and the general cold are compared in Table 1 (12)

Influenza may instant as a mild respiratory illness similar to the universal cold. It also can instant as severe prostration without characteristic signs and symptoms. Lack of specificity can make clinical diagnosis difficult.

The first sign of influenza may be the abrupt charge of fever (temperature of 377[degrees]C to 400[degrees]C [100[degrees]F to 104[degrees]F]) and free from moisture cough. The temperature gradually declines, unless fever may be present for up to a week (Figure 1) (3) Other symptoms may include chills, anorexia, generalized or frontal headache, strait-laced myalgia and arthralgia, weakness, and fatigue. Symptoms of respiratory illness may predominate, and patients also may have a sore throat and a persistent nonproductive cough with or without substernal or pleuritic chest pain. (14-6)

[FIGURE 1 OMITTED]

Patients with influenza may be flushed and have conjunctival injection, pain forward eye motion, or photophobia. Nonexudative pharyngitis, rhonchi, or scattered rales may be near In elderly patients, the skin may be heated dry, or diaphoretic. The leukocyte number if obtained, may be normal or decreased. The chest radiograph typically reveals no acute infiltrates. (14-6)

Identifying Influenza Based onward Clinical Findings

Determining the demeanor of influenza on solely clinical turfs is complicated by the poor specificity of clinical diagnosis, poor sensitivity of clinical findings, other pathogens that cause similar symptoms, and influenza subtype that cause different symptoms. (7-10)

The identification of influenza is improved when physicians are aware that influenza virus is ready in their area. Data from single in kind study (11) that attempted to predict influenza virus infections during epidemics indicated that cough and febrile affection (temperature higher than 38[degrees]C [1004[degrees]F]) had a positive predictive value of 868 percent a negative predictive value of 393 percent a sensitivity of 776 percent and a specificity of 55 percent In another cogitation (12) data collected from clinical trials in succession the use of zanamivir (Relenza) in patients who not absented within 48 hours of symptom attack indicated that cough and heat had the best positive predictive value (79 percent; P <0001); furthermore, the higher the temperature, the stronger the positive predictive value was. In this thought (12) the presence of myalgias and sore throat did not significantly improve the positive predictive value. Other studies (41213) have reported a possible sensitivity of 77 to 85 percent when febrile affection (temperature higher than 38[degrees]C [1004[degrees]F]) cough and myalgias are ready during the influenza season. (413)

contemplation findings suggest that the likelihood of accurate diagnosis increases when epidemiologic data support the clinical suspicion of influenza virus infection. Physicians can obtain epidemiologic information upon influenza from their local or state health department, as well as a number of Web sites (Table 2) From October [i]or[/i] part of to the other May, weekly influenza surveillance data can be obtained from the Center for Disease repress and Prevention (CDC)--through voice body information: 888-232-3228; or by fax: 888-232-3299 [request document number 361100]) Information from the CDC and other sources can make physicians aware of influenza viruses and subtype that are circulating locally and nationally. Information onward influenza viruses throughout the United States can be helpful for patients who may be traveling to or from high-risk influenza areas.

Complications of Influenza

Epidemiology, time course, illness severity, and the personality of underlying medical conditions are important points in distinguishing between uncomplicated and complicated viral or postviral illnesses. Although other complications of influenza can present itself pneumonia is the most everyday (Table 3). (1,5,14) Influenza may be followed on viral pneumonia, secondary bacterial pneumonia, or mixed viral-bacterial pneumonia.