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Thousand cankers disease can be spread by moving infected black walnut wood. Trees intended for shipment should be inspected for dieback and cankers and galleries after harvest. G. morbidia or the walnut twig beetle ("Pityophthorus juglandis") are not currently known to be moved with walnut seed . There is currently no chemical therapy or prevention available for the disease making it difficult to control the spread of the disease from the west to the eastern united states. Wood from infected trees can still be used for commercial value, but safety measures such as removing the bark, phloem, and cambium to reduce the risk of spreading the disease with shipment. Quarantines have been put in place in some states to reduce the potential movement of fungus or beetle from that region. On May 17th, 2010, the Director of the Michigan Department of Agriculture issued a quarantine from affected states to protect Michigan’s black walnut ecology and production. Contacting the appropriate entities about possible infections is important to stopping or slowing the spread of thousand cankers disease.
The genus Geosmithia (Ascomycota: Hypocreales) are generally saprophytic fungi affecting hardwoods. As of its identification in 2010, the species G. morbida is the first documented as a plant pathogen. The walnut twig beetle ("Pityophthorus juglandis") carries the mycelium and conidia of the fungus as it burrows into the tree. The beetle is currently only found in warmer climates, allowing for transmission of the fungus throughout the year. Generations of the beetle move to and from black walnut trees carrying the fungus as they create galleries, the adults typically moving horizontally, and the larvae moving vertically with the grain. As they move through the wood, the beetles deposit the fungus, which is then introduced into the phloem; cankers then develop around the galleries, quickly girdling the tree. The fungus has not been found to provide any value to the beetle. A study done by Montecchio and Faccoli in Italy in 2014 found that no fungal fruiting bodies were found around or on the cankers but in the galleries. Mycelium, and sometimes conidiophores and conidia were observed in the galleries as well. No sexual stage of the fungus has currently been found.
Management of Bleeding Canker of Chestnut is not definitive and treatments are currently being investigated. Because the pathogen can be spread by contaminated tools, cultural practices are important to management. Tools should be cleaned and used with caution after being used on infected trees. Recovery of trees is possible, so management strategies are focused on keeping trees healthy so they can recover. One recommendation is to add fertilizer that contains Potassium phosphate. Soil de-compaction, providing good drainage, and mulching to minimize fluctuation of soil temperature and moisture are all ways to improve or maintain tree health and to manage the pathogen.
Chemical methods can be used to help the tree maintain health and avoid progress of the disease. Management strategies are currently being developed. A study performed in 2015 examined the infection on trees and found that 41 F1 progeny parent tree source had the most promising lines of viability for resistance.
Control of Leucostoma Canker is possible through a combination of pest and crop management techniques following life cycles of the trees. The strategy is implemented following techniques aimed at reducing number of pathogenic inoculum, minimizing dead or injured tissues to prevent infection, and improving tree health to improve rapid wound healing. Chemical controls have not been very effective at controlling this disease with no fungicides registered specifically for control of "Leucostoma" spp., and demethylation-inhibiting (DMI) fungicides having almost no effect on "L. persoonii".
Plant varieties that are resistant to "Armillaria" or species are resistant to other environmental or biological stressors. If the infected area has been cleared of trees, plants that are not vulnerable to the disease should be planted for five or so years until "Armillaria" is eradicated. Stump removal is also an effective management tool but can be expensive. Another way to reduce susceptibility is to maintain plant health by regular fertilization (if needed), watering during droughts, and trying not to create wounds on the plant. Fumigation can also be used to reduce the amount of inoculum.
There are many strategies to cultural management. Establishment of new trees that are disease free by trying to plant trees as soon as they are received from the nursery to reduce the amount of stress the tree undergoes to reduce the amount of dead tissue. Apply insecticides to prevent insects such as, peach tree borer to prevent disease causing conidia from entering wounded parts of the tree that the insects create. Prune trees appropriately and at the correct time when buds start to break to promote wide angled branching. Infection at pruning sites is less common when done during late spring because of the smaller amount of inoculum present at this time. Inspect trees occasionally and removed any dead branches to prevent infection at these sites. Training trees properly also helps foster decreased amount of disease. Training trees during the first season to have branches develop wide crotch angles to sustain long orchard life. Avoid excessive and late fertilization during cold season to avoid low temperature injury. Fertilize trees during the early spring to prevent cold-susceptible growth.
The first visible sign of a beech scale insect infestation is a woolly, white, waxy covering that the insect secretes. This sign can be observed covering small areas or most of the tree. The amount of waxy material observed depends on the population of the beech scale insect on that tree. The "Neonectria" fungi also show signs of its presence. An early sign is what looks like a bleeding spot on the tree. A reddish-brown fluid will ooze from the wound site, giving it this appearance. Later, perithecia will form around the dead spot, which is another sign of the disease.
Symptoms of beech bark disease can be observed in the foliage and on the bole of the tree. Foliage may become small, sparse and yellowed. Trees that display a thin, weak crown may persist for several years but may also die without displaying any symptoms. Noticeable symptoms on the bole are the cracking of the bark, the formation of cankers, and beech snap. Beech snap is a result of the fungi and insect weakening the wood, which makes it susceptible to being blown over by wind.
There are a few controls for beech bark disease. One important management strategy is prohibiting the movement of nursery stock or other materials that may harbor the beech scale insect. Insecticides, generally not applied under forest conditions, are primarily used on high-value ornamental trees. The use of other organisms as controls is also a possibility. The ladybird beetle is a beetle that preys on the beech scale insect. A fungus that parasitizes the "Neonectria" fungus could also be employed. The problem with using these organisms to control beech bark disease is that their impact on the disease has not been evaluated extensively. In a forest setting, controlling the beech bark disease is too costly. Timely salvage cutting can reduce economic losses of beech in a forest. In stands where beech bark disease is established, silvicultural best practice is to retain large overstory trees which show visual resistance (no scale, cankers or fungus), remove heavily infested/dying trees and then treat sprouts from infested trees with herbicides. The residual, resistant parent trees are future sources of resistant seed/sprouts. Resistance to beech bark disease in a stand may be 1%-5% of trees or more, with significant regional variation. A study of 35 sites in three Canadian provinces found resistance rates ranging from 2.2%-5.7%.
Armillaria root rot is a fungal root rot caused by several different members of the genus "Armillaria". The symptoms are variable depending on the host infected, ranging from stunted leaves to chlorotic needles and dieback of twigs and branches. However, all infected hosts display symptoms characteristic of being infected by a white rotting fungus. The most effective ways of management focus on limiting the spread of the fungus, planting resistant species, and removing infected material. This disease poses a threat to the lumber industry as well as affecting recreational areas.
Shot hole disease (also called Coryneum blight) is a serious fungal disease that creates BB-sized holes in leaves, rough areas on fruit, and concentric lesions on branches. The pathogen that causes shot hole disease is "Wilsonomyces carpophilus".
Bleeding canker of horse chestnut is a common canker of horse chestnut trees ("Aesculus hippocastanum", also known as conker trees) that is known to be caused by infection with several different pathogens.
Infections by the gram-negative fluorescent bacterium "Pseudomonas syringae" pathovar "aesculi" are a new phenomenon, and have caused most of the bleeding cankers on horse chestnut that are now frequently seen in Britain.
Black pod disease is caused by many different "Phytophthora spp." pathogens all expressing the same symptoms in cocoa trees ("Theobroma cacao"). This pathogen if left untreated can destroy all yields; annually the pathogen can cause a yield loss of up to 1/3 and up to 10% of total trees can be lost completely. With the value of the cocoa industry throughout the world being so large there are much research and control efforts that go into these "Phytophthora spp." pathogens.
This pathogen can be located anywhere on the cocoa trees but is most noted for the black mummified look it will give to the fruit of the cocoa tree. Staying ahead of the pathogen is the best means of control, the pathogen can be greatly reduced if leaf litter is not allowed to stay on the ground and if the pathogen gets out of hand chemical control can be used. This pathogen is mostly found in tropical areas where the cocoa trees are located and need rainfall in order to spread its spores.
"W. carpophilus" can remain viable for several months and spores are often airborne. Since the fungi thrive in wet conditions, overhead watering should be avoided. Remove and dispose of any infected buds, leaves, fruit and twigs. In fall, fixed copper or Bordeaux mixture can be applied.
Canker and anthracnose generally refer to many different plant diseases of such broadly similar symptoms as the appearance of small areas of dead tissue, which grow slowly, often over years. Some are of only minor consequence, but others are ultimately lethal and therefore of major economic importance in agriculture and horticulture. Their causes include such a wide range of organisms as fungi, bacteria, mycoplasmas and viruses. The majority of canker-causing organisms are bound to a unique host species or genus, but a few will attack other plants. Weather and animals can spread canker, thereby endangering areas that have only slight amount of canker.
Although fungicides or bactericides can treat some cankers, often the only available treatment is to destroy the infected plant to contain the disease.
It has been observed in spiny lobsters ("Panulirus ornatus") in Vietnam, where it is caused by a species of "Fusarium".
It has been observed in shrimp, where the agent is microscopic protozoan "Hyalophysa chattoni" or a close relative, in Galveston Bay, Texas and other locations.
With extra care taken to the health of the shrimp, it is possible to prevent cases of black gill disease. The water should have 10-20 parts per thousand parts salinity and filtered.
The application of copper fungicide has been shown to significantly reduce a great number of black pod incidences in Nigeria. Metalaxyl (Ridomil) and cuprous oxide (Perenox) were identified to be successful in increasing the number of harvested healthy pod compared to the application of fosetyl aluminium (Aliete) and control treatment. On top of that, the timing of fungicide application has some positive effect on the final pod yield where this plot produced greater yield than the unsprayed plot. The application was done before August, which is before the main disease epidemic that usually occurs in September and October.
The recommended standard for fungicide application to control black pod disease caused by "P. megakarya" for a season is 6 to 8 times of application in every 3–4 weeks. However, the adoption of recommended application was very low among farmers in Ghana. Therefore, an experiment with a reduced number of fungicide applications demonstrated that there was 25 to 45% reduction in disease incidence. In terms of disease control and yields, sanitation and three applications of Ridomil 72 plus (12% metalaxyl + 60% copper-1-oxide) fungicide showed a better control compared to sanitation alone and sanitation with one or two fungicide applications. However, reduced in fungicide application was shown to be significantly less effective than the recommended standard fungicide application.
It was suggested that the understanding regarding the source of inoculum, the amount of infective inoculum production and how the disease is disseminated is important in order to identify the appropriate and economical method in fungicide application as well as for an effective control of the disease. For example, the application of fungicide on the trunk will help farmers to control the spread of the disease up in the canopy, as it is difficult to reach the canopy during fungicide application. This will eventually save more time, labor and cost for disease management.
The use of antifungals and heat-induced therapy has been suggested as a treatment of "B. dendrobatidis." " "However, some of these antifungals may cause adverse skin effects on certain species of frogs. And although we do use them to treat species that are infected by chytridiomycosis, the infection never fully eradicates. A study done by Rollins-Smith and colleagues suggests that itraconazole is the antifungal of choice when it comes to treatment of "Bd." This is favored in comparison to amphotericin B and chloramphenicol because of their toxicity, specifically chloramphenicol as it is correlated with leukemia in toads. This becomes a difficult situation because without treatment, frogs will suffer from limb deformities and even death, but may also suffer skin abnormalities with treatment. Treatment of chytridiomycosis isn’t always successful, and some frogs are not able to handle the treatment process. It is important to consult with a veterinarian before treating frogs that suffer from chytridiomycosis"."
Individuals infected with "B. dendrobatidis" are bathed in intraconazole solutions, and within a few weeks, previously infected individuals test negative for "B. dendrobatidis" using PCR assays. Heat therapy is also used to neutralize "B. dendrobatidis" in infected individuals. Temperature-controlled laboratory experiments are used to increase the temperature of an individual past the optimal temperature range of "B. dendrobatidis". Experiments, where the temperature is increased beyond the upper bound of the "B. dendrobatidis" optimal range of 25 to 30 °C, show its presence will dissipate within a few weeks and individuals infected return to normal. Formalin/malachite green has also been used to successfully treat individuals infected with chytridiomycosis. An Archey's frog was successfully cured of chytridiomycosis by applying chloramphenicol topically. However, the potential risks of using antifungal drugs on individuals are high.
Chytridiomycosis is an infectious disease in amphibians, caused by the chytrid "Batrachochytrium dendrobatidis", a nonhyphal zoosporic fungus. Chytridiomycosis has been linked to dramatic population declines or even extinctions of amphibian species in western North America, Central America, South America, eastern Australia, East Africa (Tanzania) and Dominica and Montserrat in the Caribbean. Much of the New World is also at risk of the disease arriving within the coming years.
The fungus is capable of causing sporadic deaths in some amphibian populations and 100% mortality in others. No effective measure is known for control of the disease in wild populations. Various clinical signs are seen by individuals affected by the disease. A number of options are possible for controlling this disease-causing fungus, though none has proved to be feasible on a large scale. The disease has been proposed as a contributing factor to a global decline in amphibian populations that apparently has affected about 30% of the amphibian species of the world.
There are no tests required to diagnose widow spider bites, or latrodectism symptoms. The diagnosis is clinical and based on historic evidence of widow spider bites. Pathognomonic symptoms such as localized sweating and piloerection provide evidence of envenomation. Unlike the brown recluse, the widow species are easily identified by most people.
Diagnosis is obvious in most people reporting contact with a "Latrodectus" spider. However, without a spider, either through inability to communicate or unawareness, the diagnosis may be missed as symptoms overlap with a variety of other serious clinical syndromes such as tetanus or acute abdomen. Blood values are typically unimportant but may be needed to show myocarditis or dehydration from vomiting.
Diagnosis is made primarily through physical assessment of the skin, family history of Mongolian spots, and subjective data given by the care giver. No tests are currently available for diagnosing Mongolian spots.
The gold standard for diagnosis is visualization of the amastigotes in splenic aspirate or bone marrow aspirate. This is a technically challenging procedure that is frequently unavailable in areas of the world where visceral leishmaniasis is endemic.
Serological testing is much more frequently used in areas where leishmaniasis is endemic. A 2014 Cochrane review evaluated different rapid diagnostic tests. One of them (the rK39 immunochromatographic test) gave correct, positive results in 92% of the people with visceral leishmaniasis and it gave correct, negative results in 92% of the people who did not have the disease. A second rapid test (called latex agglutination test) gave correct, positive results in 64% of the people with the disease and it gave correct, negative results in 93% of the people without the disease. Other types of tests have not been studied thoroughly enough to ascertain their efficacy.
The K39 dipstick test is easy to perform, and village health workers can be easily trained to use it. The kit may be stored at ambient temperature and no additional equipment needs to be carried to remote areas. The DAT anti-leishmania antigen test, standard within MSF, is much more cumbersome to use and appears not to have any advantages over the K39 test.
There are a number of problems with serological testing: in highly endemic areas, not everyone who becomes infected will actually develop clinical disease or require treatment. Indeed, up to 32% of the healthy population may test positive, but not require treatment. Conversely, because serological tests look for an immune response and not for the organism itself, the test does not become negative after the patient is cured, it cannot be used as a check for cure, or to check for re-infection or relapse. Likewise, patients with abnormal immune systems (e.g., HIV infection) will have false-negative tests.
Other tests being developed include detects erythrosalicylic acid.
The vast majority of victims fully recover without significant lasting problems (sequelae). Death from latrodectism is reported as high as 5% to as low as 0.2%. In the United States, where antivenom is rarely used, there have been no deaths reported for decades.
Despite frequent reference to youth and old age being a predisposing factor it has been demonstrated that young children appear to be at lowest risk for a serious bite, perhaps owing to the rapid use of antivenom. Bite victims who are very young, old, hypotensive, pregnant or who have existing heart problems are reported to be the most likely to suffer complications. However, due to the low incidence of complications these generalizations simply refer to special complications (see Special circumstances).
There are no vaccines or preventive drugs for visceral leishmaniasis. The most effective method to prevent infection is to protect from sand fly bites. To decrease the risk of being bitten, these precautionary measures are suggested:
- Outdoors:
1. Avoid outdoor activities, especially from dusk to dawn, when sand flies generally are the most active.
2. When outdoors (or in unprotected quarters), minimize the amount of exposed (uncovered) skin to the extent that is tolerable in the climate. Wear long-sleeved shirts, long pants, and socks; and tuck your shirt into your pants.
3. Apply insect repellent to exposed skin and under the ends of sleeves and pant legs. Follow the instructions on the label of the repellent. The most effective repellents generally are those that contain the chemical DEET (N,N-diethylmetatoluamide).
- Indoors:
1. Stay in well-screened or air-conditioned areas.
2. Keep in mind that sand flies are much smaller than mosquitoes and therefore can get through smaller holes.
3. Spray living/sleeping areas with an insecticide to kill insects.
4. If you are not sleeping in a well-screened or air-conditioned area, use a bed net and tuck it under your mattress. If possible, use a bed net that has been soaked in or sprayed with a pyrethroid-containing insecticide. The same treatment can be applied to screens, curtains, sheets, and clothing (clothing should be retreated after five washings)."
On February 2012, the nonprofit Infectious Disease Research Institute launched a clinical trial of the visceral leishmaniasis vaccine. The vaccine is a recombinant form of two fused Leishmania parasite proteins with an adjuvant. Two phase 1 clinical trials with healthy volunteers are to be conducted. The first one takes place in Washington (state) and is followed by a trial in India.
Ainhum is an acquired and progressive condition, and thus differs from congenital annular constrictions. Ainhum has been much confused with similar constrictions caused by other diseases such as leprosy, diabetic gangrene, syringomyelia, scleroderma or Vohwinkel syndrome. In this case, it is called pseudo-ainhum, treatable with minor surgery or intralesional corticosteroids, as with ainhum. It has even been seen in psoriasis or it is acquired by the wrapping toes, penis or nipple with hairs, threads or fibers. Oral retinoids, such as tretinoin, and antifibrotic agents like tranilast have been tested for pseudo-ainhum. Impending amputation in Vohwinkel syndrome can sometimes be aborted by therapy with oral etretinate. It is rarely seen in the United States but often discussed in the international medical literature.