Respiratory Syncytial Virus in Healthy Adults
The traditional teaching has been that respiratory syncytial virus (RSV) preferentially infects children, whereas influenza virus primarily affects older adults. However, these distinctions are beginning to be blurred. Recent data have shown that influenza virus is a common cause of infection in infants and school age children. There is now increasing evidence that RSV is a common cause of lower respiratory tract infection in adults. In one study, RSV was found to be among the four most frequent laboratory-confirmed causes of pneumonia leading to hospitalization among adults, after Streptococcus pneumoniae, influenza virus and Mycoplasma pneumoniae . Another study showed RSV to be almost as important as influenza as a cause of morbidity and mortality in the elderly . Now, a community-based study carried out in the United Kingdom shows RSV to be a common cause of influenza-like illness across the age spectrum . Nasopharyngeal swabs obtained by general practitioners were studied by polymerase chain reaction (PCR) for influenza A and B and RSV A and B. Of 2,226 swabs submitted, RSV was found in 480 (22%) and influenza was found in 709 (32%). Among adults aged 15–44 years, RSV caused 20% and influenza 30% of illnesses. Taken together, these data show considerable overlap in the clinical presentation and age spectrum of influenza and RSV. An editorial  suggests that many of the remaining influenza-like illnesses will turn out to be caused by metapneumoviruses . At last, there are some new contenders for the causation of lower respiratory tract infection in adults. These data may provide an explanation for the substantial number of infections where causes are undiagnosable by tests designed to detect influenza virus, the “big three” atypical agents, and common bacteria.
Can You Tell Inhalational Anthrax From Influenza?
Although full-fledged inhalation anthrax has a number of characteristic features (hemorrhagic mediastinal lymphadenitis, bloody pleural effusions), the initial symptom complex overlaps considerably with that of ordinary influenza infection. This has led to concern on the part of practitioners and the public. Based on the recent experience with inhalational anthrax and a large database for influenza and “influenza-like illnesses from other causes,” the Centers for Disease Control and Prevention (CDC) has pointed out several features that can help to distinguish early inhalational anthrax from the other illnesses , as shown in thetable below.
Attention to these features should provide at least some guidance in distinguishing among the illnesses in their early presentations. As suggested by the CDC, “clinicians investing persons with influenza-like illnesses should consider a combination of epidemiologic, clinical, and, if indicated, laboratory and radiographic test results to evaluate the likelihood that inhalational anthrax is the basis for ILI symptoms.”
Religion and Medicine: A Randomized Trial of Intercessory Prayer
Here is something a little different from our usual Snapshots. The role of spirituality, prayer, and support groups in actually changing the outcome of disease has been a topic of considerable interest and has been the subject of some well-done trials, but with conflicting results. A study was done at the Mayo Clinic of the effect of intercessory prayer on the progression of cardiovascular disease in a Coronary Care Unit Population . Intercessory prayer refers to prayer by one or more persons on behalf of another person. In this study, about 800 patients were randomized at discharge to the intercessory prayer group or to the control group. In the former group, prayers were administered at least once a week for 26 weeks by 5 intercessors per patient. To preserve anonymity of patients but allow for a relationship, the intercessors were provided with the patient’s first name, age, sex, diagnosis, and general condition. Patients and caregivers were blinded as to patient assignment. The primary endpoint at the end of 26 weeks was any of death, cardiac arrest, rehospitalization for cardiovascular disease, coronary revascularization, or an emergency room visit for cardiovascular disease. Overall, an endpoint occurred in 25.6% of the prayer group and 29.3% of the control group, a difference that was not statistically significant (p = .25). In patients at high risk for such an endpoint, the differences were still not statistically significant (31.0% vs 33.3%;p = .60). In low risk patients, there was also no significant difference (17.0% vs 24.1%;p = .12). The authors conclude that intercessory prayer had no observable effect on the outcome of disease. Those interested in reading more on this subject may also consult an excellent editorial  and review article  in the same issue.
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