Streptococcus mutans is a facultatively anaerobic, gram-positive coccus (round bacterium) commonly found in the human oral cavity and is a significant contributor to tooth decay. It is part of the "streptococci" (plural, non-italic lowercase), an informal general name for all species in the genus lovemeen.com microbe was first described by James Kilian Clarke in 5) Staphylococcus and Streptococcus can usually be differentiated by microscope examination because of A) cell shape. B) Gram stain reaction. C) cell arrangement. .
True or False: Washing your hands with soaps that have residue-producing antibacterial products, such as those containing the chemical triclosan, have been proven to confer health benefits. Washing with regular soap is considered the most important way to prevent disease transmission. Routine consumer use of residue-producing antibacterial products has no added benefit and may actually contribute to antibiotic resistance. Part of the U. Department of Health and Human Services and the National Institutes of Health, NIAID conducts and supports basic and applied research to better understand, treat, and ultimately prevent infectious, immunologic, and allergic diseases.
Search the National Academies Press website by selecting one of these related terms. The National Academies. How Infection Works. How Pathogens Make Us Sick. Infection occurs when virusesbacteriaor other microbes enter your body and begin to multiply. Disease occurs when the cells in your body are damaged as a result of infection and signs and symptoms of an illness appear.
The incidence of disease among those infected varies greatly depending on the particular pathogen and individual susceptibility. Many of the symptoms that make a person suffer during an infectionЧfever, malaise, headache, rashЧresult from the activities of the immune system trying to eliminate the infection from the body. In response to infection, your immune system springs into action.
White blood cellsantibodiesand other mechanisms go to work to rid your body of the foreign invader. Indeed, many of the symptoms that make a person suffer during an infectionЧfever, malaise, headache, rashЧresult from the activities of the immune system trying to eliminate the infection from the body. Pathogenic microbes challenge the immune system in many ways. Viruses whatever happened to burt ward us sick by killing cells or disrupting cell function.
Many bacteria make us sick in the same way that viruses do, but they also have other strategies at their disposal. Sometimes bacteria multiply so rapidly they crowd out host tissues and disrupt normal function. Sometimes they kill cells and tissues outright. The protozoa that cause malariawhich are members of the what fish are compatible with african cichlids Plasmodium, have complex life cycles.
Sporozoites, the stage of the parasite that infects new hosts, develop in the salivary glands of Anopheles mosquitos. Cells infected with sporozoites eventually burst, releasing another cell form, merozoites, into the bloodstream. These cells infect red blood cells and then rapidly reproduce, destroying the red blood cell hosts and releasing many new merozoites to do further damage. Most merozoites continue to reproduce in this way, but some differentiate into sexual forms gametocytes that are taken up by the female mosquito, thus completing the protozoan life cycle.
In response to infection, your immune system springs into action. White blood cells, antibodies, and other mechanisms go to work to rid your body of the foreign lovemeen.com, many of the symptoms that make a person suffer during an infectionЧfever, malaise, headache, rashЧresult from the activities of the immune system trying to eliminate the infection from the body. They reproduce only asexually. Bacteria can be beneficial e.g. we have bacteria in our intestinal tracts which aid in - Skin infections - Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa. Examples of diseases caused by viruses are: Colds, Influenza, Chicken pox, Cold Sores. the antibiotics kill susceptible bacteria, but the few that are naturally resistant live and reproduce, and their progeny repopulate the host animal. Streptococcus pyogenes Mycoplasma penicillinase-producing Neisseria gonorrhoeae Penicillium helminths. Streptococcus pyogenes.
WONG, D. DEAN A. LISA G. LOWE, M. Patient information: See related handout on when to use antibiotics , written by the authors of this article.
To help physicians with the appropriate use of antibiotics in children and adults with upper respiratory tract infection, a multidisciplinary team evaluated existing guidelines and summarized key practice points. Acute otitis media in children should be diagnosed only if there is abrupt onset, signs of middle ear effusion, and symptoms of inflammation.
A period of observation without immediate use of antibiotics is an option for certain children. In patients with sinus infection, acute bacterial rhinosinusitis should be diagnosed and treated with antibiotics only if symptoms have not improved after 10 days or have worsened after five to seven days.
In patients with sore throat, a diagnosis of group A beta-hemolytic streptococcus pharyngitis generally requires confirmation with rapid antigen testing, although other guidelines allow for empiric therapy if a validated clinical rule suggests a high likelihood of infection.
Acute bronchitis in otherwise healthy adults should not be treated with antibiotics; delayed prescriptions may help ease patient fears and simultaneously reduce inappropriate use of antibiotics. The Centers for Disease Control and Prevention CDC estimates that more than million antibiotic prescriptions are written each year in the ambulatory care setting. In addition to antibiotics prescribed for upper respiratory tract infections with viral etiologies, broad-spectrum antibiotics are used too often when a narrow-spectrum antibiotic would have been just as effective.
Clinical criteria that assist in the diagnosis of acute otitis media include the abrupt onset of signs and symptoms, the presence of middle ear effusion, and signs or symptoms of middle ear inflammation. A period of observation is appropriate for select children with acute otitis media and nonsevere symptoms. A diagnosis of acute bacterial rhinosinusitis should be considered in patients with symptoms of a viral upper respiratory infection that have not improved after 10 days or that worsen after five to seven days.
Treatment of sinus infection with antibiotics in the first week of symptoms is not recommended. Amantadine Symmetrel and rimantadine Flumadine should not be used for the treatment of influenza because of widespread resistance. Acute bronchitis in otherwise healthy adults should not be treated with antibiotics. Telling patients not to fill an antibiotic prescription unless symptoms worsen or fail to improve after several days can reduce the inappropriate use of antibiotics.
In one study, up to 50 percent of parents had a previsit expectation of receiving an antibiotic prescription for their children, and one third of physicians perceived an expectation for a prescription.
However, researchers have found no association between receiving an antibiotic prescription and satisfaction with the office visit. What does impact satisfaction is whether patients understood their illness after the visit and whether they felt that their physician spent enough time with them. Increased antibiotic resistance is not inevitable. For example, Finland demonstrated the success of a nationwide effort to reduce antibiotic resistance following an increase in erythromycin resistance among patients with group A streptococci in the early s.
This project began in January The work group is composed of practicing physicians, academic physicians, pharmacists, and nurses. No one from the pharmaceutical industry was involved in the development of the compendia. Given the breadth of this topic, the focus of this article is on the appropriate use of antibiotics and not on the use of adjunctive treatments such as antitussives, decongestants, and inhalers, although they play an important role in disease management and symptomatic relief.
The guidelines discussed here address the care of otherwise healthy patients without major comorbidities in the outpatient setting. A work group was formed in late to provide overall direction in the development of clinical practice materials and resources.
The process began with a literature search for each respiratory tract infection. Next, the practice guidelines developed for each disease by the leading medical organizations were compiled. Members of the work group then prioritized the reference articles and guidelines to be included in the review process.
The compendia are shown in Tables 1 and 2. Otitis media Streptococcus pneumoniae , nontypeable Haemophilus influenzae , Moraxella catarrhalis. When to treat with an antibiotic: Recent, usually abrupt onset of signs and symptoms of middle ear inflammation and effusion.
Presence of middle ear effusion that is indicated by any of the following: bulging of the tympanic membrane, limited or absent mobility of tympanic membrane, air fluid level behind the tympanic membrane, otorrhea. Signs or symptoms of middle ear inflammation as indicated by distinct erythema of the tympanic membrane. Distinct otalgia discomfort clearly referable to the ear[s] that interferes with or precludes normal activity or sleep.
Age group Younger than six months: antibiotics. Six months to two years: antibiotics if diagnosis certain; antibiotics if diagnosis uncertain and severe illness.
Oral: ibuprofen or acetaminophen may use acetaminophen with codeine for moderate-severe pain. First-line therapy High-dosage amoxicillin 80 to 90 mg per kg per day. Nonanaphylactic penicillin-allergic: cefdinir Omnicef , cefpodoxime Vantin , or cefuroxime Ceftin. Acute bacterial sinusitis S.
When to treat with an antibiotic: Diagnosis may include some or all of the following symptoms or signs: nasal drainage, nasal congestion, facial pressure or pain especially when unilateral and focused in the region of a particular sinus , postnasal discharge, hyposmia, anosmia, fever, cough, fatigue, maxillary dental pain, ear pressure or fullness.
Nearly all cases of acute bacterial sinusitis resolve without antibiotics. Antibiotic use should be reserved for moderate symptoms not improving after 10 days or that worsen after five to seven days, and severe symptoms. Failure to respond after 72 hours of antibiotics: reevaluate patient and switch to alternate antibiotic. Fiberoptic endoscopy or sinus aspiration for culture may be necessary. First-line therapy Amoxicillin 80 to 90 mg per kg per day.
Pharyngitis Streptococcus pyogenes , routine respiratory viruses. When to treat with an antibiotic: S. Symptoms and signs: sore throat, fever, headache, nausea, vomiting, abdominal pain, tonsillopharyngeal erythema, exudates, palatal petechiae, tender enlarged anterior cervical lymph nodes.
Confirm diagnosis with throat culture or rapid antigen testing; negative rapid antigen test results should be confirmed with throat culture. Respiratory viral causes, conjunctivitis, cough, rhinorrhea, diarrhea uncommon with group A streptococcal infection. Group A streptococcal infection: Treatment reserved for patients with positive rapid antigen test or throat culture. When to treat with an antibiotic: Presents with prolonged unimproving cough 14 days ; should clinically differentiate from pneumonia.
Pertussis should be reported to public health authorities. Treatment reserved for B. Macrolides tetracyclines for children older than eight years. Adequate fluid intake; may advise rest, over-the-counter medications, humidifier. Although the summary describes recommended courses of intervention, it is not intended as a substitute for the advice of a physician or other knowledgeable health care professionals.
These guidelines represent best clinical practice at the time of publication, but practice standards may change as more knowledge is gained. Adapted with permission from California Medical Association Foundation.
Acute bacterial sinusitis Streptococcus pneumoniae , nontypeable Haemophilus influenzae, Moraxella catarrhalis , mainly viral pathogens.
When to treat with an antibiotic: diagnosis may be made in adults with symptoms of a viral upper respiratory infection that have not improved after 10 days or that worsen after five to seven days. Diagnosis may include some or all of the following: nasal drainage, nasal congestion, facial pressure or pain especially when unilateral and focused in the region of a particular sinus , postnasal discharge, hyposmia, anosmia, fever, cough, fatigue, maxillary dental pain, ear pressure or fullness.
Failure to respond after 72 hours of antibiotics: reevaluate patient and switch to alternate antibiotics. When not to treat with an antibiotic: nearly all cases resolve without antibiotics. Antibiotic use should be reserved for moderate symptoms that are not improving after 10 days or that worsen after five to seven days, and severe symptoms. Symptoms of sore throat, fever, headache.
Physical findings include fever, tonsillopharyngeal erythema and exudates, palatal petechiae, tender and enlarged anterior cervical lymph nodes, and absence of cough. Confirm diagnosis with throat culture or rapid antigen testing before using antibiotics; negative rapid antigen test results may be confirmed with throat culture.
Amoxicillin, macrolides erythromycin preferred in patients allergic to penicillin , oral cephalosporins, clindamycin Cleocin.
When not to treat with an antibiotic: most pharyngitis cases are viral in origin. The presence of the following is uncommon with group A streptococcal infection and points away from using antibiotics: conjunctivitis, cough, rhinorrhea, diarrhea, and absence of fever. When to treat with an antibiotic: antibiotics not indicated in patients with uncomplicated acute bacterial bronchitis. Sputum characteristics not helpful in determining need for antibiotics. Treatment is reserved for patients with acute bacterial exacerbation of chronic bronchitis and COPD, usually smokers.
In patients with severe symptoms, rule out other more serious conditions e. Other B. When not to treat with an antibiotic: 90 percent of cases are nonbacterial. Literature fails to support use of antibiotics in adults without history of chronic bronchitis or other comorbid condition. Nonspecific upper respiratory infection Viral.
When not to treat with an antibiotic: Antibiotics not indicated; however, nonspecific upper respiratory infection is a major etiologic cause of acute respiratory illnesses presenting to primary care physicians. Patients often expect treatment. Attempt to discourage antibiotic use and explain appropriate treatment.
Influenza Influenza virus. When not to treat with an antibiotic: antibiotics not indicated. For acute treatment, supportive and symptomatic care is the standard. Characterized by abrupt onset of constitutional and respiratory signs and symptoms such as fever, myalgia, headache, rhinitis, severe malaise, nonproductive cough, and sore throat.. Antiviral medications available for acute relief of symptoms and for prevention in some cases.
The incubation period for influenza is one to four days, with an average of two days. Adults typically are infectious from the day before symptoms begin through approximately five days after onset of illness. Three elements must be met to confirm the diagnosis of acute otitis media. The first element is the recent, usually abrupt onset of signs and symptoms of middle ear inflammation and effusion.
The second element is the presence of middle ear effusion as indicated by bulging of the tympanic membrane, limited or absent mobility of the tympanic membrane, air fluid level behind the tympanic membrane, or otorrhea.