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Due to the high number of hosts, eradication of tungiasis is not feasible, at least not easily so. Public health and prevention strategies should then be done with elimination as the target. Better household hygiene, including having a cemented rather than a sand floor, and washing it often, would lower the rates of tungiasis significantly.
Though vaccines would be useful, due to the ectoparasitic nature of chigoe flea, they are neither a feasible nor an effective tool against tungiasis. Nevertheless, due to the high incidence of secondary infection, those at risk of tungiasis should get vaccinated against tetanus. A better approach is to use repellents that specifically target the chigoe flea. One very successful repellent is called Zanzarin, a derivative of coconut oil, jojoba oil, and aloe vera. In a recent study involving two cohorts, the infestation rates dropped 92% on average for the first one and 90% for the other. Likewise, the intensity of the cohorts dropped by 86% and 87% respectively. The non-toxic nature of Zanzarin, combined with its "remarkable regression of the clinical pathology" make this a tenable public health tool against tungiasis.
The use of pesticide, like DDT, has also led to elimination of the "Tunga penetrans", but this control/prevention strategy should be utilized very carefully, if at all, because of the possible side effects such pesticides can have on the greater biosphere. In the 1950s, there was a worldwide effort to eradicate malaria. As part of that effort, Mexico launched the Campaña Nacional para la Erradicación de Paludismo, or the National Campaign for the Eradication of Malaria. By spraying DDT in homes, the Anopheles a genus of mosquitoes known to carry the deadly Plasmodium falciparum was mostly eliminated. As a consequence of this national campaign, other arthropods were either eliminated or significantly reduced in number, including the reduviid bug responsible for Chagas disease (American Trypanosomiasis) and "T. penetrans". Controlled, in-home spraying of DDT is effective as it gives the home immunity against arthropods while not contaminating the local water supplies and doing as much ecological damage as was once the case when DDT was first introduced.
While other species gradually gained resistance to DDT and other insecticides that were used, "T. penetrans did" not; as a result, the incidence of tungiasis in Mexico is very low when compared to the rest of Latin America, especially Brazil, where rates in poor areas have been known to be as high or higher than 50%. There was a 40-year period with no tungiasis cases in Mexico. It was not until August 1989 that three Mexican patients presented with the disease. Though there were other cases of tungiasis reported thereafter, all were acquired in Africa.
Because of the relatively rapid onset of tungiasis, the incubation period tends to be short. Although some reddening around the site of penetration occurs, the first symptoms are perceived in stage 2 as itching and severe pain, usually a day after penetration.
Until recently humans and water fleas ("Cyclops") were regarded as the only animals this parasite infects. It has been shown that baboons, cats, dogs, frogs and catfish ("Synodontis") can also be infected naturally. Ferrets have been infected experimentally.
Dracunculiasis is caused by drinking water contaminated by water fleas that host the "D. medinensis" larvae. Dracunculiasis has a history of being very common in some of the world's poorest areas, particularly those with limited or no access to clean water. In these areas, stagnant water sources may still host copepods, which can carry the larvae of the guinea worm.
After ingestion, the copepods die and are digested, thus releasing the stage 3 larvae, which then penetrate the host's stomach or intestinal wall, and then enter into the abdominal cavity and retroperitoneal space. After maturation, which takes approximately three months, mating takes place; the male worm dies after mating and is absorbed by the host's body.
Approximately one year after mating, the fertilized females migrate in the subcutaneous tissues adjacent to long bones or joints of the extremities. They then move towards the surface, resulting in blisters on the skin, generally on the distal lower extremity (foot). Within 72 hours, the blister ruptures, exposing one end of the emergent worm. The blister causes a very painful burning sensation as the worm emerges, and the sufferer will often immerse the affected limb in water to relieve the burning sensation. When a blister or open sore is submerged in water, the adult female releases hundreds of thousands of stage 1 guinea worm larvae, thereby contaminating the water.
During the next few days, the female worm can release more larvae whenever it comes in contact with water, as it extends its posterior end through the hole in the host's skin. These larvae are eaten by copepods, and after two weeks (and two molts), the stage 3 larvae become infectious and, if not filtered from drinking water, will cause the cycle to repeat. Infected copepods can live in the water for up to four months.
The male guinea worm is typically much smaller () than the female, which, as an adult, can grow to long and be as thick as a spaghetti noodle.
Infection does not create immunity, so people can repeatedly experience Dracunculiasis throughout their lives. Several worms may emerge simultaneously; the average is 1.8. Up to 14 worms have been reported in one individual.
In drier areas just south of the Sahara desert, cases of the disease often emerge during the rainy season, which for many agricultural communities is also the planting or harvesting season. Elsewhere, the emerging worms are more prevalent during the dry season, when ponds and lakes are smaller and copepods are thus more concentrated in them. Guinea worm disease outbreaks can cause serious disruption to local food supplies and school attendance.
The infection can be acquired by eating a fish paratenic host, but this is rare. No reservoir hosts are known; that is, each generation of worms must pass through a human – or possibly a dog.
The hypothesis that pesticide use has contributed to declining amphibian populations has been suggested several times in the literature. Interactions between pesticides and chytridiomycosis were examined in 2007, and sublethal exposure to the pesticide carbaryl (a cholinesterase inhibitor) was shown to increase susceptibility of foothill yellow-legged frogs ("Rana boylii") to chytridiomycosis. In particular, the skin peptide defenses were significantly reduced after exposure to carbaryl, suggesting pesticides may inhibit this innate immune defence, and increase susceptibility to disease.
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.
Chiggers are commonly found on the tip of blades of grasses to catch a host, so keeping grass short, and removing brush and wood debris where potential mite hosts may live, can limit their impact on an area. Sunlight that penetrates the grass will make the lawn drier and make it less favorable for chigger survival.
Chiggers seem to affect warm covered areas of the body more than drier areas. Thus, the bites are often clustered behind the knees, or beneath tight undergarments such as socks, underwear, or brassieres. Areas higher in the body (chest, back, waist-band, and under-arms) are affected more easily in small children than in adults, since children are shorter and are more likely than adults to come in contact with low-lying vegetation and dry grass where chiggers thrive. An exceptional case has been described in the eye, producing conjunctivitis.
Application of repellent to the shoes, lower trousers and skin is also useful. Because they are found in grass, staying on trails, roads, or paths can prevent contact. Dusting sulfur is used commercially for mite control and can be used to control chiggers in yards. The dusting of shoes, socks and trouser legs with sulfur can be highly effective in repelling chiggers.
Another good strategy is to recognize the chigger habitat to avoid exposure in the first place. Chiggers in North America thrive late in summer, in dry tall grasses and other thick, unshaded vegetation. Insect repellents containing one of the following active ingredients are recommended: DEET, catnip oil extract (nepetalactone), citronella oil or eucalyptus oil extract. However, in 1993 issue a study reported on tests of two commercial repellents: DEET and citrus oil: "All chiggers exposed on the filter papers treated with DEET died and did not move off the treated papers. None of the chiggers that were placed on papers treated with citrus oil were killed." It was concluded that DEET was more effective than citrus oil.
Chiggers can also be treated using common household vinegar (5% acetic acid).
Trombiculosis, trombiculiasis, or trombiculidiasis is a rash caused by trombiculid mites which is often referred to as a chigger bite.
Pulicosis (also known as "flea bites") is a skin condition caused by several species of fleas, including the cat flea ("Ctenocephalides felis") and dog flea ("Ctenocephalides canis"). This condition can range from mild irritation to severe irritation. In some cases, 48 to 72 hours after being bitten, a more severe rash-like irritation may begin to spread across the body. Symptoms include swelling of the bitten area, erythema, ulcers of the mouth and throat, restlessness, and soreness of the areolae. In extreme cases, within 1 week after being bitten, the condition may spread through the lymph nodes and begin affecting the central nervous system. Permanent nerve damage can occur.
If they receive an excessive number of bites, pets can also develop flea allergy dermatitis, which can potentially be fatal if no actions are taken. However, dogs and cats are not the only ones that are at risk. Humans can suffer from flea bites and, depending on a variety of factors, the bites can cause much pain and discomfort.
Carrión's disease, or Oroya fever, or Peruvian wart is a rare infectious disease found only in Peru, Ecuador, and Colombia. It is endemic in some areas of Peru, is caused by infection with the bacterium "Bartonella bacilliformis", and transmitted by sandflies of genus "Lutzomyia".
Cat scratch disease occurs worldwide. Cats are the main reservoir of "Bartonella henselae", and the bacterium is transmitted to cats by the cat flea "Ctenocephalides felis". Infection in cats is very common with a prevalence estimated between 40-60%, younger cats being more commonly infective. Cats usually become immune to the infection, while dogs may be very symptomatic. Humans may also acquire it through flea or tick bites from infected dogs, cats, coyotes, and foxes.
Trench fever, produced by "Bartonella quintana" infection, is transmitted by the human body louse "Pediculus humanus corporis". Humans are the only known reservoir. Thorough washing of clothing may help to interrupt the transmission of infection.
A possible role for ticks in transmission of "Bartonella" species remains to be elucidated; in November 2011, "Bartonella rochalimae", "B. quintana", and "B. elizabethae" DNA was first reported in "Rhipicephalus sanguineus" and "Dermacentor nitens" ticks in Peru.
While curable, BA is potentially fatal if not treated. BA responds dramatically to several antibiotics. Usually, erythromycin will cause the skin lesions to gradually fade away in the next four weeks, resulting in complete recovery. Doxycycline may also be used. However, if the infection does not respond to either of these, the medication is usually changed to tetracycline. If the infection is serious, then a bactericidal medication may be coupled with the antibiotics
If a cat is carrying "Bartonella henselae", then it may not exhibit any symptoms. Cats may be bacteremic for weeks to years, but infection is more common in young cats. Transmission to humans is thought to occur via flea feces inoculated into a cat scratch or bite, and transmission between cats occurs only in the presence of fleas. Therefore, elimination and control of fleas in the cat's environment are key to prevention of infection in both cats and humans.
Bacillary angiomatosis (BA) is a form of angiomatosis associated with bacteria of the "Bartonella" genus.
Cat-scratch disease has a worldwide distribution, however it is a nonreportable disease in humans and therefore public health data on this disease is inadequate. Geographical location, present season and variables associated with cats (such as exposure and degree of flea infestation) all play a factor in the prevalence of Cat-scratch disease within a population. In warmer climates, the incidence of Cat-scratch disease is more prevalent during the fall and winter months. The higher rate of Cat-scratch disease during those months may be attributed to the breeding season for adult cats, which allows for the birth of kittens". B henselae," the bacterium responsible for causing Cat-scratch disease, is more prevalent in younger cats [less than one year old] than it is in adult cats.
To determine recent incidence of Cat-scratch disease in the United States, the Truven Health MarketScan Commercial Claims and Encounters database was analyzed in a case control study from 2005-2013. The database consisted of healthcare insurance claims for employees, their spouses, and their dependents. All participants were under 65 years of age, from all 50 states. The length of the study period was 9 years and was based off 280,522,578 person-years; factors such as year, length of insurance coverage, region, age, and sex were used to calculate the person-years incidence rate to eliminate confounding variables among the entire study population. 13,273 subjects were diagnosed with Cat-scratch disease, both in and outpatient cases were analyzed. The study revealed an incidence rate of 4.5/100,000 outpatient cases of Cat-scratch disease. For inpatient cases, the incidence rate was much lower at 0.19/100,000 population. Incidence of Cat-scratch disease was highest in 2005 among outpatient cases and then slowly declined. The Southern states saw the most significant decrease of incidence overtime. Mountain regions have the lowest incidence of this disease because fleas are not a common vector found in these areas.
Distribution of Cat-scratch disease among children aged 5-9 were of the highest incidence in the analyzed database, followed by woman aged 60-64. Incidence among female patients was higher than that among male patients in all age groups. According to data on social trends, women are more likely to own a cat over men; which supports higher incidence rates of this disease in women. Risk of contracting Cat-scratch disease increases as the number of cats residing in the home increases. The number of pet cats in the United States is estimated to be at 57 million. Due to the large population of cats residing in the United States, the ability of this disease to continue to infect humans is vast. Laboratory diagnosis of Cat-scratch disease has improved in recent years, which may support an increase in incidence of Cat-scratch disease in future populations.
Treatment of infections caused by "Bartonella" species include:
Some authorities recommend the use of azithromycin.
The diagnosis of flea allergy dermatitis is complicated by the grooming habits of pets. Cats in particular are very efficient at grooming out fleas, often removing any evidence of infestation. Fleas begin biting within 5 minutes of finding a host, and there are no flea treatments that kill fleas before biting occurs.
The cat should be taken to a veterinarian. The most suspected cause of skin problems in cats will be fleas. Other causes of over-grooming are not as easily ascertained. As household antiseptics are known to be toxic to cats, veterinary antiseptics for cats can be used to treat open sores, if they do occur. Sores can also be treated with cream, oral or injected anti-inflammatories, however if the problem continues to recur it may be more cost effective to subject the cat to laboratory testing early on. It may be difficult to keep a clean dressing on a cat's belly, and an anti-lick collar is adequate to let the wound heal. If an anti lick collar is used, a soft anti-lick collar is less cumbersome, although they are less durable. If the cat wears a plastic anti-lick collar, it may use the edge of the collar to grind against existing wounds, making them worse. A soft anti lick collar will become less effective as it is kicked out of the shape by the cat's hind leg, and will need prompt replacement. The cat can sanitize the wound if the collar is removed for daily short periods of time, also giving the cat an opportunity for an overall grooming. Scratches and wounds can heal completely using this method. When the cat stops wearing the collar, thinned hair, redness of skin or cracked nipples on the cat are early indicators that the cat has started to over-groom again.
Antidepressants for cats may be suggested by a vet.
Cat-scratch disease can be primarily prevented by taking flea control measures and washing hands after handling a cat or cat feces; since cats are mostly exposed to fleas when they are outside, keeping cats inside can prevent infestation.
The flea found most commonly on both dogs and cats with a flea infestation is the cat flea, "Ctenocephalides felis". Pets that develop FAD have an allergic response to flea saliva injected during flea feeding. The itch associated with just one flea bite persists long after that flea is gone and leads to significant self-trauma.
The most important infectious skin diseases of cats is ringworm or dermatophytosis. Other cat skin infections include parasitic diseases like mange and lice infestation.
Other ectoparasites, including flea and tick infestations are not considered directly contagious but are acquired from an environment where other infested hosts have established the parasite's life cycle.
Another common skin infection is cat bite abscess. A mixture of bacteria introduced by a bite wound cause infections in pockets under the skin and affected cats often show manic depression and fever.
Murine typhus (also called endemic typhus) is a form of typhus transmitted by fleas (Xenopsylla cheopis), usually on rats. (This is in contrast to epidemic typhus, which is usually transmitted by lice.) Murine typhus is an under-recognized entity, as it is often confused with viral illnesses. Most people who are infected do not realize that they have been bitten by fleas.
Grooming is a natural behavior for cats. Cats spend 5%-25% of their waking hours grooming. Grooming becomes excessive when it takes precedence over other activities or no longer seems functional. Excessive grooming, which can lead to hair loss, skin wounds, and ulceration, can result from chronic stress or develop in cats who already exhibit nervous temperaments. Even when the source of stress is resolved or removed, excessive grooming may continue. There may be some genetic basis for the behavior, and it predominantly affects purebred cats of oriental breeds, but can develop in any feline. Female cats appear more susceptible. Environmental factors suspected of causing over grooming include flea allergy, boredom, food allergy, dust or pollen causing an allergic reaction, constipation and/or urinary tract infection caused by avoidance of a dirty litter tray, dermatitis, anxiety caused by inconsistent meal times. Deprivation of sunlight could be the part of the problem for indoors only cats.
The following steps and precautions should be used to avoid infection of the septicemic plague:
- Caregivers of infected patients should wear masks, gloves, goggles and gowns
- Take antibiotics if close contact with infected patient has occurred
- Use insecticides throughout house
- Avoid contact with dead rodents or sick cats
- Set traps if mice or rats are present around the house
- Do not allow family pets to roam in areas where plague is common
- Flea control and treatment for animals (especially rodents)
The cat must have a supply of niacin, as cats cannot convert tryptophan into niacin like dogs. However, diets high in corn and low in protein can result in skin lesions and scaly, dry, greasy skin, with hair loss. Another B vitamin, biotin, if deficient causes hair loss around the eyes and face. A lack of B vitamins can be corrected by supplementing with a vitamin B complex, and brewers yeast.
Sylvatic plague is most commonly found in prairie dog colonies; the flea that feeds on prairie dogs (and other mammals) serves as the vector for transmission to the new host.
Sylvatic plague is primarily transmitted among wildlife through flea bites and contact with contaminated fluids or tissue, through predation or scavenging. Humans can contract plague from wildlife through flea bites and handling animal carcasses.