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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.
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.
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.
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.
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.
Appropriate antibiotic treatment should be started immediately when there is a suspicion of Rocky Mountain spotted fever on the basis of clinical and epidemiological findings. Treatment should not be delayed until laboratory confirmation is obtained. In fact, failure to respond to a tetracycline argues against a diagnosis of Rocky Mountain spotted fever. Severely ill patients may require longer periods before their fever resolves, especially if they have experienced damage to multiple organ systems. Preventive therapy in healthy patients who have had recent tick bites is not recommended and may, in fact, only delay the onset of disease.
Doxycycline (a tetracycline) (for adults at 100 milligrams every 12 hours, or for children under at 4 mg/kg of body weight per day in two divided doses) is the drug of choice for patients with Rocky Mountain spotted fever, being one of the only instances doxycycline is used in children. Treatment should be continued for at least three days after the fever subsides, and until there is unequivocal evidence of clinical improvement. This will be generally for a minimum time of five to ten days. Severe or complicated outbreaks may require longer treatment courses. Doxycycline/ tetracycline is also the preferred drug for patients with ehrlichiosis, another tick-transmitted infection with signs and symptoms that may resemble those of Rocky Mountain spotted fever.
Chloramphenicol is an alternative drug that can be used to treat Rocky Mountain spotted fever, specifically in pregnancy. However, this drug may be associated with a wide range of side effects, and careful monitoring of blood levels can be required.
The "Candid #1" vaccine for AHF was created in 1985 by Argentine virologist Dr. Julio Barrera Oro. The vaccine was manufactured by the Salk Institute in the United States, and became available in Argentina in 1990.
"Candid #1" has been applied to adult high-risk population and is 95.5% effective. On 29 August 2006 the Maiztegui Institute obtained certification for the production of the vaccine in Argentina. A vaccination plan is yet to be outlined, but the budget for 2007 allows for 390,000 doses, at AR$8 each (about US$2.6 or €2 at the time). The Institute has the capacity to manufacture, in one year, the 5 million doses required to vaccinate the entire population of the endemic area.
Between 1991 and 2005 more than 240,000 people were vaccinated, achieving a great decrease in the numbers of reported cases (94 suspect and 19 confirmed in 2005).
The Junín vaccine has also shown cross-reactivity with Machupo virus and, as such, has been considered as a potential treatment for Bolivian hemorrhagic fever.
Rocky Mountain spotted fever can be a very severe illness and patients often require hospitalization. Because "R. rickettsii" infects the cells lining blood vessels throughout the body, severe manifestations of this disease may involve the respiratory system, central nervous system, gastrointestinal system, or kidneys.
Long-term health problems following acute Rocky Mountain spotted fever infection include partial paralysis of the lower extremities, gangrene requiring amputation of fingers, toes, or arms or legs, hearing loss, loss of bowel or bladder control, movement disorders, and language disorders. These complications are most frequent in persons recovering from severe, life-threatening disease, often following lengthy hospitalizations
The disease was first reported in the town of in Buenos Aires province, Argentina in 1958, giving it one of the names by which it is known. Various theories about its nature were proposed: it was Weil's disease, leptospirosis, caused by chemical pollution. It was associated with fields containing stubble after the harvest, giving it another of its names.
The endemic area of AHF covers approximately 150,000 km², compromising the provinces of Buenos Aires, Córdoba, Santa Fe and La Pampa, with an estimated risk population of 5 million.
The vector, a small rodent known locally as "ratón maicero" ("maize mouse"; "Calomys musculinus"), suffers from chronic asymptomatic infection, and spreads the virus through its saliva and urine. Infection is produced through contact of skin or mucous membranes, or through inhalation of infected particles. It is found mostly in people who reside or work in rural areas; 80% of those infected are males between 15 and 60 years of age.
Veterinary treatment of babesiosis does not normally use antibiotics. In nonhuman animals, diminazen (Berenil), imidocarb, or trypan blue would be the drugs of choice for treatment of "B. canis rossi" (dogs in Africa), "B. bovis", and "B. bigemina" (cattle in Southern Africa). In acute cases in cattle, blood transfusion may be carried out.
A vaccine is effective against "B. canis canis" (dogs in the Mediterranean region), but is ineffective against "B. c. rossi". "B. imitans" causes a mild form of the disease that frequently resolves without treatment (dogs in Southeast Asia).
Trench fever (also known as "five-day fever", "quintan fever" ("febris quintana" in Latin), and "urban trench fever") is a moderately serious disease transmitted by body lice. It infected armies in Flanders, France, Poland, Galicia, Italy, Salonika, Macedonia, Mesopotamia, Russia and Egypt in World War I. Three noted sufferers during WWI were the authors J.R.R. Tolkien, A. A. Milne, and C.S. Lewis. From 1915 to 1918 between one-fifth and one-third of all British troops reported ill had trench fever while about one-fifth of ill German and Austrian troops had the disease. The disease persists among the homeless. Outbreaks have been documented, for example, in Seattle and Baltimore in the United States among injection drug users and in Marseille, France, and Burundi.
Trench fever is also called Wolhynia fever, shin bone fever, Meuse fever, His disease and His–Werner disease (after Wilhelm His, Jr. and Heinrich Werner).
The disease is caused by the bacterium "Bartonella quintana" (older names: "Rochalimea quintana", "Rickettsia quintana"), found in the stomach walls of the body louse. "Bartonella quintana" is closely related to "Bartonella henselae", the agent of cat scratch fever and bacillary angiomatosis.
A number of vaccines against canine distemper exist for dogs (ATCvet code: and combinations) and domestic ferrets (), which in many jurisdictions are mandatory for pets. Infected animals should be quarantined from other dogs for several months owing to the length of time the animal may shed the virus. The virus is destroyed in the environment by routine cleaning with disinfectants, detergents, or drying. It does not survive in the environment for more than a few hours at room temperature (20–25 °C), but can survive for a few weeks in shady environments at temperatures slightly above freezing. It, along with other labile viruses, can also persist longer in serum and tissue debris.
Despite extensive vaccination in many regions, it remains a major disease of dogs.
To prevent canine distemper, puppies should begin vaccination at six to eight weeks of age and then continue getting the “booster shot” every two to four weeks until they are 16 weeks of age. Without the full series of shots, the vaccination will not provide protection against the virus. Since puppies are typically sold at the age of eight to ten weeks, they typically receive the first shot while still with their breeder, but the new owner often does not finish the series. These dogs are not protected against the virus and so are susceptible to canine distemper infection, continuing the downward spiral that leads to outbreaks throughout the country.
The mortality rate of the virus largely depends on the immune status of the infected dogs. Puppies experience the highest mortality rate, where complications such as pneumonia and encephalitis are more common. In older dogs that develop distemper encephalomyelitis, vestibular disease may present. Around 15% of canine inflammatory central nervous system diseases are a result of CDV.
Treatment of asymptomatic carriers should be considered if parasites are still detected after 3 months. In mild-to-moderate babesiosis, the treatment of choice is a combination of atovaquone and azithromycin. This regimen is preferred to clindamycin and quinine because side effects are fewer. The standard course is 7 to 10 days, but this is extended to at least 6 weeks in people with relapsing disease. Even mild cases are recommended to be treated to decrease the chance of inadvertently transmitting the infection by donating blood. In life-threatening cases, exchange transfusion is performed. In this procedure, the infected red blood cells are removed and replaced with uninfected ones.
Imizol is a drug used for treatment of babesiosis in dogs.
Extracts of the poisonous, bulbous plant "Boophone disticha" are used in the folk medicine of South Africa to treat equine babesiosis. "B. disticha" is a member of the daffodil family Amaryllidaceae and has also been used in preparations employed as arrow poisons, hallucinogens, and in embalming. The plant is rich in alkaloids, some of which display an action similar to that of scopolamine.
Though the introduction of national guidelines to screen pregnant women for GBS carriage and the use of IAP has significantly reduced the burden of GBS-EOD disease, it has had no effect on preventing either GBS-LOD in infants or GBS infections in adults. Because of this, if an effective vaccine against GBS were available, it would be an effective means of controlling not only GBS disease in infants, but also infections in adults. The capsular polysaccharide of GBS, which is an important virulence factor, is also an excellent candidate for the development of an effective vaccine. As early as 1976, low levels of maternal antibodies against the capsular polysaccharide were shown to be correlated with susceptibility to GBS-EOD and GBS-LOD. Maternal-specific antibodies, transferred from the mother to the newborn, were able to confer protection to babies against GBS infection.
Vaccination is considered an ideal solution to prevent not only GBS-EOD and GBS-LOD, but also infections in adults at risk. Nevertheless, though research and clinical trials for the development of an effective vaccine to prevent GBS infections are underway, no vaccine is available in 2016. At present, the licensing of GBS vaccines is difficult because of the challenge in conducting efficacy clinical trials in humans due to the low incidence of GBS neonatal diseases.
Because "B. suis" is facultative and intracellular, and is able to adapt to environmental conditions in the macrophage, treatment failure and relapse rates are high. The only effective way to control and eradicate zoonosis is by vaccination of all susceptible hosts and elmination of infected animals. The "Brucella abortus" (rough LPS "Brucella") vaccine, developed for bovine brucellosis and licensed by the USDA Animal Plant Health Inspection Service, has shown protection for some swine and is also effective against "B. suis" infection, but currently no approved vaccine for swine brucellosis is available.
There are currently no Food and Drug Administration-approved vaccines for the prevention of MVD. Many candidate vaccines have been developed and tested in various animal models. Of those, the most promising ones are DNA vaccines or based on Venezuelan equine encephalitis virus replicons, vesicular stomatitis Indiana virus (VSIV) or filovirus-like particles (VLPs) as all of these candidates could protect nonhuman primates from marburgvirus-induced disease. DNA vaccines have entered clinical trials. Marburgviruses are highly infectious, but not very contagious. Importantly, and contrary to popular belief, marburgviruses do not get transmitted by aerosol during natural MVD outbreaks. Due to the absence of an approved vaccine, prevention of MVD therefore relies predominantly on behavior modification, proper personal protective equipment, and sterilization/disinfection.
July has been recognised as Group B Strep Awareness Month, a time when information about group B Strep aimed at families and health professionals is shared, predominantly in the UK and the US. In the UK, this is led by Group B Strep Support
Marburgviruses are World Health Organization Risk Group 4 Pathogens, requiring Biosafety Level 4-equivalent containment, laboratory researchers have to be properly trained in BSL-4 practices and wear proper personal protective equipment.
Unfortunately a vaccine for malignant catarrhal fever (MCF) has not yet been developed. Developing a vaccine has been difficult because the virus will not grow in cell culture and until recently it was not known why. Researchers at the Agricultural Research Service (ARS) found that the virus undergoes changes within the animal's body, a process known as "cell tropism switching". In cell tropism switching, the virus targets different cells at different points in its life cycle. This phenomenon explains why it has been impossible to grow the virus on any one particular cell culture.
Because the virus is transmitted from sheep to bison and cattle, researchers are first focusing on the viral life cycle in sheep. The viral life cycle is outlined in three stages: entry, maintenance, and shedding. Entry occurs through the sheep's nasal cavity and enters into the lungs where it replicates. The virus undergoes a tropic change and infects lymphocytes, also known as white blood cells, which play a role in the sheep's immune system. In the maintenance stage the virus remains on the sheep's lymphocytes and circulates the body. Finally, during the shedding stage, the virus undergoes another change and shifts its target cells from lymphocytes to nasal cavity cells, where it is then shed through nasal secretions. This discovery undoubtedly puts scientists on the right track for developing a vaccine – starting with the correct cell culture for each stage of the virus lifecycle – but ARS researchers are also looking into alternative methods to develop a vaccine. Researchers are experimenting with the MCF virus that infects topi (an African antelope) because it will grow in cell culture and does not infect cattle. Researchers hope that inserting genes from the sheep MCF virus into the topi MCF virus will ultimately be an effective MCF vaccine for cattle and bison. While there is much ground left to cover, scientists are getting closer and closer to developing a vaccine.
The mainstay of eradication is the identification and removal of persistently infected animals. Re-infection is then prevented by vaccination and high levels of biosecurity, supported by continuing surveillance. PIs act as viral reservoirs and are the principal source of viral infection but transiently infected animals and contaminated fomites also play a significant role in transmission.
Leading the way in BVD eradication, almost 20 years ago, were the Scandinavian countries. Despite different conditions at the start of the projects in terms of legal support, and regardless of initial prevalence of herds with PI animals, it took all countries approximately 10 years to reach their final stages.
Once proven that BVD eradication could be achieved in a cost efficient way, a number of regional programmes followed in Europe, some of which have developed into national schemes.
Vaccination is an essential part of both control and eradication. While BVD virus is still circulating within the national herd, breeding cattle are at risk of producing PI neonates and the economic consequences of BVD are still relevant. Once eradication has been achieved, unvaccinated animals will represent a naïve and susceptible herd. Infection from imported animals or contaminated fomites brought into the farm, or via transiently infected in-contacts will have devastating consequences.
Outbreaks of zoonoses have been traced to human interaction with and exposure to animals at fairs, petting zoos, and other settings. In 2005, the Centers for Disease Control and Prevention (CDC) issued an updated list of recommendations for preventing zoonosis transmission in public settings. The recommendations, developed in conjunction with the National Association of State Public Health Veterinarians, include educational responsibilities of venue operators, limiting public and animal contact, and animal care and management.
Methicillin-resistant Staphylococcus aureus (MRSA) evolved from Methicillin-susceptible Staphylococcus aureus (MSSA) otherwise known as common "S. aureus". Many people are natural carriers of "S. aureus", without being affected in any way. MSSA was treatable with the antibiotic methicillin until it acquired the gene for antibiotic resistance. Though genetic mapping of various strains of MRSA, scientists have found that MSSA acquired the mecA gene in the 1960s, which accounts for its pathogenicity, before this it had a predominantly commensal relationship with humans. It is theorized that when this "S. aureus" strain that had acquired the mecA gene was introduced into hospitals, it came into contact with other hospital bacteria that had already been exposed to high levels of antibiotics. When exposed to such high levels of antibiotics, the hospital bacteria suddenly found themselves in an environment that had a high level of selection for antibiotic resistance, and thus resistance to multiple antibiotics formed within these hospital populations. When "S. aureus" came into contact with these populations, the multiple genes that code for antibiotic resistance to different drugs were then acquired by MRSA, making it nearly impossible to control. It is thought that MSSA acquired the resistance gene through the horizontal gene transfer, a method in which genetic information can be passed within a generation, and spread rapidly through its own population as was illustrated in multiple studies. Horizontal gene transfer speeds the process of genetic transfer since there is no need to wait an entire generation time for gene to be passed on. Since most antibiotics do not work on MRSA, physicians have to turn to alternative methods based in Darwinian medicine. However prevention is the most preferred method of avoiding antibiotic resistance. By reducing unnecessary antibiotic use in human and animal populations, antibiotics resistance can be slowed.
The term "bovine malignant catarrhal fever" has been applied to three different patterns of disease:
- In Africa, wildebeests carry a lifelong infection of AlHV-1 but are not affected by the disease. The virus is passed from mother to offspring and shed mostly in the nasal secretions of wildebeest calves under one year old. Wildebeest associated MCF is transmitted from wildebeest to cattle normally following the wildebeest calving period. Cattle of all ages are susceptible to the disease, with a higher infection rate in adults, particularly in peripartuent females. Cattle are infected by contact with the secretions, but do not spread the disease to other cattle. Because no commercial treatment or vaccine is available for this disease, livestock management is the only method of control. This involves keeping cattle away from wildebeest during the critical calving period. This results in Massai pastoralists in Tanzania and Kenya being excluded from prime pasture grazing land during the wet season leading to a loss in productivity. In Eastern and Southern Africa MCF is classed as one of the five most important problems affecting pastoralists along with East coast fever, contagious bovine pleuropneumonia, foot and mouth disease and anthrax.Hartebeests and topi also may carry the disease. However, hartebeests and other antelopes are infected by a variant, Alcelaphine herpesvirus 2.
- Throughout the rest of the world, cattle and deer contract BMCF by close contact with sheep or goats during lambing. The natural host reservoir for Ovine herpesvirus 2 is the subfamily Caprinae (sheep and goats) whilst MCF affected animals are from the families Bovidae, Cervidae and suidae. Susceptibility to OHV-2 varies by species, with domestic cattle and zebus somewhat resistant, water buffalo and most deer somewhat susceptible, and bison, Bali cattle, and Pere David's deer very susceptible. OHV-2 viral DNA has been detected in the alimentary, respiratory and urino-genital tracts of sheep all of which could be possible transmission routes. Antibody from sheep and from cattle with BMCF is cross reactive with AlHV-1.
- AHV-1/OHV-2 can also cause problems in zoological collections, where inapparently infected hosts (wildebeest and sheep) and susceptible hosts are often kept in close proximity.
- Feedlot bison in North America not in contact with sheep have also been diagnosed with a form of BMCF. OHV-2 has been recently documented to infect herds of up to 5 km away from the nearest lambs, with the levels of infected animals proportional to the distance away from the closest herds of sheep.
The incubation period of BMCF is not known, however intranasal challenge with AHV-1 induced MCF in one hundred percent of challenged cattle between 2.5 and 6 weeks.
Shedding of the virus is greater from 6–9 month old lambs than from adults. After experimental infection of sheep, there is limited viral replication in nasal cavity in the first 24 hours after infection, followed by later viral replication in other tissues.
Modern vaccination programmes aim not only to provide a high level of protection from clinical disease for the dam, but, crucially, to protect against viraemia and prevent the production of PIs. While the immune mechanisms involved are the same, the level of immune protection required for foetal protection is much higher than for prevention of clinical disease.
While challenge studies indicate that killed, as well as live, vaccines prevent foetal infection under experimental conditions, the efficacy of vaccines under field conditions has been questioned. The birth of PI calves into vaccinated herds suggests that killed vaccines do not stand up to the challenge presented by the viral load excreted by a PI in the field.