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Pontiac fever does not spread from person to person. It is acquired through aersolization of water droplets and/or potting soil containing "Legionella" bacteria.
Sources of the causative agents are aquatic systems and potting soil. The first outbreak caused by inhalation of aersolized potting soil was discovered in New Zealand in January 2007. A total of 10 workers at a nursery came down with Pontiac fever. It was the first identification of "L. longbeachae".
Although the risk of Legionnaires' disease being spread by large-scale water systems cannot be eliminated, it can be greatly reduced by writing and enforcing a highly detailed, systematic water safety plan appropriate for the specific type of facility involved (office building, hospital, hotel, spa, cruise ship, etc.) Some of the elements that such a plan may include are the following:
- Keeping water temperature either above or below the range in which the "Legionella" bacterium thrives.
- Preventing stagnation, for example by removing from a network of pipes any sections that have no outlet (dead ends). Where stagnation is unavoidable, for example when a wing of a hotel is closed for the off-season, systems must be thoroughly disinfected just prior to resuming normal operation.
- Preventing the buildup of biofilm, for example by not using (or by replacing) construction materials that encourage its development, and by reducing the quantity of nutrients for bacterial growth that enter the system.
- Periodic disinfection of the system, by high heat or a chemical biocide, and the use of chlorination where appropriate.
- System design (or renovation) that reduces the production of aerosols and reduces human exposure to them, for example by directing them well away from building air intakes.
An effective water safety plan will also cover such matters as training, record-keeping, communication among staff, contingency plans and management responsibilities. The format and content of the plan may be prescribed by public health laws or regulations. There is tentative evidence for the treatment of the water with copper-silver ionization or ultraviolet light.
The fatality rate of Legionnaires' disease has ranged from 5% to 30% during various outbreaks and approaches 50% for nosocomial infections, especially when treatment with antibiotics is delayed. Hospital-acquired "Legionella" pneumonia has a fatality rate of 28%, and the principal source of infection in such cases is the drinking-water distribution system.
Protection is offered by Q-Vax, a whole-cell, inactivated vaccine developed by an Australian vaccine manufacturing company, CSL Limited. The intradermal vaccination is composed of killed "C. burnetii" organisms. Skin and blood tests should be done before vaccination to identify pre-existing immunity, because vaccinating people who already have an immunity can result in a severe local reaction. After a single dose of vaccine, protective immunity lasts for many years. Revaccination is not generally required. Annual screening is typically recommended.
In 2001, Australia introduced a national Q fever vaccination program for people working in “at risk” occupations. Vaccinated or previously exposed people may have their status recorded on the Australian Q Fever Register, which may be a condition of employment in the meat processing industry. An earlier killed vaccine had been developed in the Soviet Union, but its side effects prevented its licensing abroad.
Preliminary results suggest vaccination of animals may be a method of control. Published trials proved that use of a registered phase vaccine (Coxevac) on infected farms is a tool of major interest to manage or prevent early or late abortion, repeat breeding, anoestrus, silent oestrus, metritis, and decreases in milk yield when "C. burnetii" is the major cause of these problems.
Providing basic sanitation and safe drinking water and food is the key for controlling the disease. In developed countries, enteric fever rates decreased in the past when treatment of municipal water was introduced, human feces were excluded from food production, and pasteurization of dairy products began. In addition, children and adults should be carefully educated about personal hygiene. This would include careful handwashing after defecation and sexual contact, before preparing or eating food, and especially the sanitary disposal of feces. Food handlers should be educated in personal hygiene prior to handling food or utensils and equipment. Infected individuals should be advised to avoid food preparation. Sexually active people should be educated about the risks of sexual practices that permit fecal-oral contact.
Those who travel to countries with poor sanitation should receive a live attenuated typhoid vaccine—Ty21a (Vivotif), which, in addition to the protection against typhoid fever, and may provide some protection against paratyphoid fever caused by the "S. enterica" serotypes A and B. In particular, a reanalysis of data from a trial conducted in Chile showed the Ty21a vaccine was 49% effective (95% CI: 8–73%) in preventing paratyphoid fever caused by the serotype B. Evidence from a study of international travelers in Israel also indicates the vaccine may prevent a fraction of infections by the serotype A, although no trial confirms this. This cross-protection by a typhoid vaccine is most likely due to O antigens shared between different "S. enterica" serotypes.
Exclusion from work and social activities should be considered for symptomatic, and asymptomatic, people who are food handlers, healthcare/daycare staff who are involved in patient care and/or child care, children attending unsanitary daycare centers, and older children who are unable to implement good standards of personal hygiene. The exclusion applies until two consecutive stool specimens are taken from the infected patient and are reported negative.
A drug-resistant strain of scarlet fever, resistant to macrolide antibiotics such as erythromycin, but retaining drug-sensitivity to beta-lactam antibiotics such as penicillin, emerged in Hong Kong in 2011, accounting for at least two deaths in that city—the first such in over a decade. About 60% of circulating strains of the group A "Streptococcus" which cause scarlet fever in Hong Kong are resistant to macrolide antibiotics, says Professor Kwok-yung Yuen, head of Hong Kong University's microbiology department. Previously, observed resistance rates had been 10–30%; the increase is likely the result of overuse of macrolide antibiotics in recent years.
Control requires treatment of antibiotics and vaccines prescribed by a doctor. Major control treatments for paratyphoid fever include ciprofloxacin for ten days, ceftriaxone/cefotaxime for 14 days, or aziththromycin.
One method is long term use of antibiotics to prevent future group A streptococcal infections. This method is only indicated for people who have had complications like recurrent attacks of acute rheumatic fever or rheumatic heart disease. Antibiotics are limited in their ability to prevent these infections since there are a variety of subtypes of group A streptococci that can cause the infection.
The vaccine approach has a greater likelihood of effectively preventing group A streptococcal infections because vaccine formulations can target multiple subtypes of the bacteria. A vaccine developed by George and Gladys Dick in 1924 was discontinued due to poor efficacy and the introduction of antibiotics. Difficulties in vaccine development include the considerable strain variety of group A streptococci present in the environment and the amount of time and number of people needed for appropriate trials for safety and efficacy of any potential vaccine. There have been several attempts to create a vaccine in the past few decades. These vaccines, which are still in the development phase, expose to the person to proteins present on the surface of the group A streptococci to activate an immune response that will prepare the person to fight and prevent future infections.
There used to be a diphtheria scarlet fever vaccine. It was, however, found not to be effective. This product was discontinued by the end of World War II.
Doxycycline has been provided once a week as a prophylaxis to minimize infections during outbreaks in endemic regions. However, there is no evidence that chemoprophylaxis is effective in containing outbreaks of leptospirosis, and use of antibiotics increases antibiotics resistance. Pre-exposure prophylaxis may be beneficial for individuals traveling to high-risk areas for a short stay.
Effective rat control and avoidance of urine contaminated water sources are essential preventive measures. Human vaccines are available only in a few countries, such as Cuba and China. Animal vaccines only cover a few strains of the bacteria. Dog vaccines are effective for at least one year.
Treatment of acute Q fever with antibiotics is very effective and should be given in consultation with an infectious diseases specialist. Commonly used antibiotics include doxycycline, tetracycline, chloramphenicol, ciprofloxacin, ofloxacin, and hydroxychloroquine. Chronic Q fever is more difficult to treat and can require up to four years of treatment with doxycycline and quinolones or doxycycline with hydroxychloroquine.
Q fever in pregnancy is especially difficult to treat because doxycycline and ciprofloxacin are contraindicated in pregnancy. The preferred treatment is five weeks of co-trimoxazole.
Effective antibiotics include penicillin G, ampicillin, amoxicillin and doxycycline. In more severe cases cefotaxime or ceftriaxone should be preferred.
Glucose and salt solution infusions may be administered; dialysis is used in serious cases. Elevations of serum potassium are common and if the potassium level gets too high special measures must be taken. Serum phosphorus levels may likewise increase to unacceptable levels due to kidney failure.
Treatment for hyperphosphatemia consists of treating the underlying disease, dialysis where appropriate, or oral administration of calcium carbonate, but not without first checking the serum calcium levels (these two levels are related). Administration of corticosteroids in gradually reduced doses (e.g., prednisolone) for 7–10 days is recommended by some specialists in cases of severe hemorrhagic effects. Organ-specific care and treatment are essential in cases of kidney, liver, or heart involvement.
When proper treatment is provided for patients with rat-bite fever, the prognosis is positive. Without treatment, the infection usually resolves on its own, although it may take up to a year to do so. A particular strain of rat-bite fever in the United States can progress and cause serious complications that can be potentially fatal. Before antibiotics were used, many cases resulted in death. If left untreated, streptobacillary rat-bite fever can result in infection in the lining of the heart, covering over the spinal cord and brain, or in the lungs. Any tissue or organ throughout the body may develop an abscess.
Currently, no vaccine against relapsing fever is available, but research continues. Developing a vaccine is very difficult because the spirochetes avoid the immune response of the infected person (or animal) through antigenic variation. Essentially, the pathogen stays one step ahead of antibodies by changing its surface proteins. These surface proteins, lipoproteins called variable major proteins, have only 30–70% of their amino acid sequences in common, which is sufficient to create a new antigenic "identity" for the organism. Antibodies in the blood that are binding to and clearing spirochetes expressing the old proteins do not recognize spirochetes expressing the new ones. Antigenic variation is common among pathogenic organisms. These include the agents of malaria, gonorrhea, and sleeping sickness. Important questions about antigenic variation are also relevant for such research areas as developing a vaccine against HIV and predicting the next influenza pandemic.
It is important to reduce the amount of environmental contamination to prevent the spread of insects or fomites. Owners should regularly apply insect repellent and routinely check their horses for open wounds to prevent chance of infection. A regular manure management program is recommended, including removal of soiled feed and bedding, as the bacteria can survive in hay and shavings for up to two months. Since the disease lives in the ground and is spread by flies, pest control is a good defense but not a guarantee. Horses being introduced to new environments should be quarantined and any infected horses should be isolated to prevent spread of the bacteria. There is currently no vaccination for Pigeon Fever.
While obviously preventable by staying away from rodents, otherwise hands and face should be washed after contact and any scratches both cleaned and antiseptics applied. The effect of chemoprophylaxis following rodent bites or scratches on the disease is unknown. No vaccines are available for these diseases.
Improved conditions to minimize rodent contact with humans are the best preventive measures. Animal handlers, laboratory workers, and sanitation and sewer workers must take special precautions against exposure. Wild rodents, dead or alive, should not be touched and pets must not be allowed to ingest rodents.
Those living in the inner cities where overcrowding and poor sanitation cause rodent problems are at risk from the disease. Half of all cases reported are children under 12 living in these conditions.
This bacterium is present in soil and is transmitted to horses through open wounds, abrasions or mucous membranes.
Tonsillectomy may be a reasonable preventive measure in those with frequent throat infections (more than three a year). However, the benefits are small and episodes typically lessen in time regardless of measures taken. Recurrent episodes of pharyngitis which test positive for GAS may also represent a person who is a chronic carrier of GAS who is getting recurrent viral infections. Treating people who have been exposed but who are without symptoms is not recommended. Treating people who are carriers of GAS is not recommended as the risk of spread and complications is low.
Untreated streptococcal pharyngitis usually resolves within a few days. Treatment with antibiotics shortens the duration of the acute illness by about 16 hours. The primary reason for treatment with antibiotics is to reduce the risk of complications such as rheumatic fever and retropharyngeal abscesses; antibiotics are effective if given within 9 days of the onset of symptoms.
Relapsing fever is easily treated with a one- to two-week-course of antibiotics, and most people improve within 24 hours. Complications and death due to relapsing fever are rare.
Tetracycline-class antibiotics are most effective. These can, however, induce a Jarisch–Herxheimer reaction in over half those treated, producing anxiety, diaphoresis, fever, tachycardia and tachypnea with an initial pressor response followed rapidly by hypotension. Recent studies have shown tumor necrosis factor-alpha may be partly responsible for this reaction.
As resistance to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, and streptomycin is now common, these agents have not been used as first–line treatment of typhoid fever for almost 20 years. Typhoid resistant to these agents is known as multidrug-resistant typhoid (MDR typhoid).
Ciprofloxacin resistance is an increasing problem, especially in the Indian subcontinent and Southeast Asia. Many centres are shifting from using ciprofloxacin as the first line for treating suspected typhoid originating in South America, India, Pakistan, Bangladesh, Thailand, or Vietnam. For these people, the recommended first-line treatment is ceftriaxone. Also, azithromycin has been suggested to be better at treating typhoid in resistant populations than both fluoroquinolone drugs and ceftriaxone. Azithromycin significantly reduces relapse rates compared with ceftriaxone.
A separate problem exists with laboratory testing for reduced susceptibility to ciprofloxacin: current recommendations are that isolates should be tested simultaneously against ciprofloxacin (CIP) and against nalidixic acid (NAL), and that isolates that are sensitive to both CIP and NAL should be reported as "sensitive to ciprofloxacin", but that isolates testing sensitive to CIP but not to NAL should be reported as "reduced sensitivity to ciprofloxacin". However, an analysis of 271 isolates showed that around 18% of isolates with a reduced susceptibility to ciprofloxacin (MIC 0.125–1.0 mg/l) would not be picked up by this method. How this problem can be solved is not certain, because most laboratories around the world (including the West) are dependent on disk testing and cannot test for MICs.
Tetracycline-group antibiotics (doxycycline, tetracycline) are commonly used. Chloramphenicol is an alternative medication recommended under circumstances that render use of tetracycline derivates undesirable, such as severe liver malfunction, kidney deficiency, in children under nine years and in pregnant women. The drug is administered for seven to ten days.
The treatment for bacillary angiomatosis is erythromycin given for three to four months.
No vaccines are currently available to protect against "S. pyogenes" infection, although research is underway to develop one. Difficulties in developing a vaccine include the wide variety of strains of "S. pyogenes" present in the environment and the large amount of time and people that will be needed for appropriate trials for safety and efficacy of the vaccine.
Conventional "amphotericin B desoxycholate" (AmB: used since the 1950s as a primary agent) is known to be associated with increased drug-induced Nephrotoxicity (Renal toxicity) impairing Renal function. Other formulations have been developed such as lipid soluble formulations to mitigate such side-effects as direct proximal and distal tubular cytotoxicity. These include liposomal amphotericin B, "amphotericin B lipid complex" such as Abelcet (brand) "amphotericin B phospholipid complex" also as "AmBisome Intravenous", or "Amphotec Intravenous" (Generic; Amphotericin B Cholesteryl Sul) and, "amphotericin B colloidal dispersion", all shown to exhibit a decrease in nephrotoxicity. The later was not as effective in one study as "amphotericin B desoxycholate" which had a 50% murine morbidity rate versus zero for the AmB colloidal dispersion.
The cost of AmB deoxycholate in 2015, for a patient of at 1 mg/kg/day dosage, was approximately $63.80, compared to 5 mg/kg/day of liposomal AmB at $1318.80. This may be a concern in resource-limited settings.
Preventing Valley fever is challenging because it is difficult to avoid breathing in the fungus should it be present, however, the public health effect of the disease is essential to understand in areas where the fungus is endemic. Enhancing surveillance of Coccidiodomycosis is key to preparedness in the medical field in addition to improving diagnostics for early infections. Currently there are no completely effective preventive measures available for people who live or travel through Valley Fever -endemic areas. Recommended preventive measures include avoiding airborne dust or dirt, but this does not guarantee protection against infection. People in certain occupations may be advised to wear face masks. The use of air filtration indoors is also helpful, in addition to keeping skin injuries clean and covered to avoid skin infection.
In 1998-2011, there were 111,117 cases of coccidioidomycosis in the U.S. that were logged into the National Notifiable Diseases Surveillance System (NNDSS). Since many U.S. states do not require reporting of coccidioidomycosis, the actual numbers can be higher. The United States' Centers for Disease Control and Prevention (CDC) called the disease a "silent epidemic" and acknowledged that there is no proven anticoccidioidal vaccine available. Studies done in the past show that the cost benefit of a vaccine is most notable among infants, teens, and immigrant adults, with negative cost-benefit results among older age groups.
Raising both surveillance and awareness of the disease while medical researchers are developing a human vaccine can positively contribute towards prevention efforts. Research demonstrates that patients from endemic areas who are aware of the disease are most likely to request diagnostic testing for coccidioidomycosis. Presently, Meridian Bioscience manufactures the so-called "EIA test" to diagnose the Valley fever, which however is known for producing a fair quantity of false positives. Currently, recommended prevention measures can include type-of-exposure-based respirator protection for persons engaged in agriculture, construction and others working outdoors in endemic areas. Dust control measures such as planting grass and wetting the soil, and also limiting exposure to dust storms are advisable for residential areas in endemic regions.