Essay: Skin diseases

Introduction: Skin diseases relating to travel are common and there are different types of microbial agents and vectors which may lead to infections. Knowing the type of infections in different geographical regions may help to prevent the appearance of infection. Vaccines, repellents, bed nets and clothes are recommended for preventing the infections.
Purpose: The main purpose of this review is to introduce common skin disorders and the prevalence of diseases in different regions, clinical protests, prevention, clinical diagnosis and treatment.
Conclusion: Informing and advising travelers are the best way to prevent infectious diseases.
Keywords: Skin Infection, Infections in traveler, Soft tissue infection, Review
Introduction
Skin is the largest organ of body that acts as a barrier against pathogenic microorganisms. The type and amount of the skin micro flora are directly in association with the level of skin moisture, temperature, pH etc. [1]. Diarrhea, fever and the skin diseases are respectively first, second and third most common infectious diseases among travelers [2]. Previously, skin diseases were limited in specific geographical regions, but in recent decades the progression of transport technology has led to increase the number of travelers in global level [3]. There is a diversity of reported skin disorders among travelers including insect bites, cutaneous larva migrans (CLM), skin abscesses, infectious insect bite reaction, allergic rashes, dog bite, super facial fungal infection, dengue, scabies, cutaneous leishmaniasis, rickettsia spotted fever, viral chikungunya [4].
Patients with skin infections must be evaluated throughout a series of questions and travelling history involving the region and place of travel, the economic level of the travel, the individual behavior and the use of aboriginal cosmetic materials etc. to have an accurate diagnosis.
The types of clinical samples including direct microscopic observation, biopsy, culture, serologic investigations are related to the specific clinical manifestations [4].
Epidemiology
In a study, the most common skin disorders among American travelers were related to insects’ bites and stings [5].
The result of a British investigation indicated that the skin diseases are the third most common disease in developing countries right after systemic febrile disease and acute diarrhea. The type and number of skin diseases varies in patients who have traveled; however, the geographical area is considerably important. According to previous reports, the South Africa and Caribbean regions travelers are more in risk for skin infections diseases [3].
In an international study the skin infections were the most common disease after fever and diarrhea among travelers. The most common risk factors for skin infections involve insect bite, skin abscess, allergic reaction and CLM [5, 6].
Common skin Infections
Bacterial skin infections
Bacterial skin infections are the most common skin disorders among travelers. The clinical manifestations include: necrotizing cellulitis, abscesses, ecthyma, erysipelas, impetigo. The signs of skin disorders appear right after infection in the length of travel [6].
In an investigation impetigo, ecthyma or erysipelas were recognized as the most common bacterial cutaneous infections with the total percentage of 75%. The predominant causative bacterial agents of impetigo are recorded as Staphylococcus aureus and Streptococcus species [5]. Insects’ bites are common causes of skin lesions, which are pertaining to secondary infections or hypersensitivity reactions [7].
Staphylococcus aureus and Streptococcus beta haemolytic group including Lancefield groups of A, C, G are known as the common bacterial causes of skin and soft tissue infection in diabetic and the elderly patients [1].
For treating skin infections caused by staphylococcus aureus and streptococcus spp. the use of effective antibiotics such as penicillinase-resistant penicillins, cephalosporins, clindamycin, or vancomysin (for penicillin sensitive patients) is recommended. The skin wounds must be cleaned with disinfection agents in parallel with antibiotic therapy [5, 8, 9].
Hookworm related CLM (HRCLM)
The HRLCM is recognized as the most common skin disease among travelers of tropical and subtropical regions [6, 10]. HRCLM is caused by animal nematode larvae entering throughout the skin host in contaminated places. The symptom appearance varies from several days to several months. In some surveys, the developing time of HRCLM is reported in different ranges of 10-15 days and more than 7 months [5, 10-13]. Localized itching is a common HRCLM symptom at the erupted area of the skin, which has been reported in 98 to 100% of the patients [11]. The most predominant and common HRCLM symptom is creeping dermatitis as a differentiate clinical demonstration including red skin lines or tracks which have a thickness of about 3 mm and a length of 15 to 20 mm. The main numbers of the lesions are usually 1 to 3 in an individual [5, 11].
The two considerable clinical symptoms in patients with HRCLM on the larvae period of the causative infectious agent are known as edema and vesiculobullous lesions. The percentage of local swelling and vesiculobullous soreness manifestations are respectively reported in ranges of 6-17% and 4-40% in patients. People whose skins are in exposure with contaminated soil are in highest risk of the infection [5, 13, 14].
The disease demonstrations in association with HRCLM are mostly seen in feet (>50%), tights and buttocks. The eruption usually disappears between 2 to 8 weeks as a sign of self limitation [5, 7, 10, 13].
HRCLM clinical diagnostics are based on clinical manifestations and the recent history of travel to tropical regions and beaches. The additional differential diagnosis other than general skin diseases is creeping dermatitis [5].
The first choice antibiotics for HRCLM treatment are recommended as albendazole and oral ivermectin. One dose of ivermectin is effective with an efficacy of 94 to 100%. For treating hookworm folliculitis, a repeated course of aforementioned oral antibiotics is preferred [10].
By the appearance of sensitivity to oral consumption of the antibiotics in patients, it is possible to replace them with albendazole or thiabendazole ointments [5].
Insects’ bites and stings
Different types of insects with a wide range of bites and stings are seen worldwide. They belong to a special geographical region for the most with their specific life cycles and hosts. The most considered insects with bites are including fleas, mosquitoes, bedbugs, midges, tsetse and sand flies. Depending on the ability of the host immune system, severity or sensitivity may be seen via the lack or the presence of allergic reactions. The skin reactions are resulted from immunological or chemical answers to the entrance of the insect’s saliva into the host’s skin. The insect’s bite may lead to transitional or long-term infectious disease in the host [4].
The most insects’ bites are not painful excluding tsetse and midge bites. People usually are bitten in rural areas and tourism camps. Any contact with animals during the travel may lead to skin infections due to insects’ bites. Rapid inflations are seen in individuals with severe allergic reaction which is in association with local release of histamine; where the skin is bitten by an insect. Bare ankle, elbow and foot in travelers are preferred places to be bitten by the insects. According to previous studies, the cluster pattern of the bites are relating to flying insects while, reptiles’ bites possess a linear pattern.
The immune system reactions against an insect bite get resolved in future days or weeks. The manifestation of the skin reaction against an insect bite is normally circular (1-5 cm in diameter) with a reddened center and pinkish surrounding with itching [4].
The clinical history symptoms together with histological examination are known as a qualified diagnostic method for recognizing skin infectious diseases [4].
The use of insect repellent materials, mosquito nets, and wearing suitable clothes are best choices to prevent being bitten by the insects.
For treating bitten skins, topical ointments such as betamethasone and oral consumption of antihistamine are recommended [4].
Tsetse fly bite
Tsetse flies (Glossina spp.) as large and medically important insects are observed in Africa. They feed different hosts including domestic and wild animals and humans. The adult male and female flies transmit the protozoan pathogen of Trypanosoma brucei. T.brucei protozoan cells are transmitted into the bloodstream of the bitten human host which may cause the African trypanosomiasis or sleeping sickness. Global travels from different parts of the world into the African continent have increased the number of infected travelers. The clinical demonstrations of the bite involving a small sore with hardened lymph nodes in the bitten skin area resemble syphilis symptoms. The spread of the pathogenic protozoa in bloodstream and cerebrospinal fluid (CSF) of the human host may lead to death [4].
Abscesses
Several studies show that the individual hygiene and the economy level of travelers are two important factors for being kept healthy. There are different causative physical agents for abscess including trauma and insect bites. Nowadays, the number of travelers with abscesses has noticeably increased. The most considerable bacterial agent which may lead to traveler’s abscesses is known as Staphylococcus aureus. According to previous investigations, abscesses caused by S.aureus strains which encompass the gene toxin of panton-valentine leucocidin may be managed and treated throughout abscess drainage. Antibiotic therapy is a suitable choice for people who are identified as carriers of S.aureus via their skin or nose [4].
Cutaneous leishmaniasis
Leishmania is the obligate intracellular protozoan agent of leishmaniasis. Cutaneous leishmaniasis is a common form of leismaniasis among travelers which is detectable in tropical and sub-tropical regions including the Middle East countries, Asia, southern Europe, and Latin America. Sandflies are the well-known transmitters of cutaneous leishmaniasis [5, 16]. The most cases of cutaneous leishmaniasis are reported from South America and the Middle East regions [16, 17].
The well-known symptoms of cutaneous leishmaniais are characterized by the wounds which may appear on the traveler’s skin between weeks to years. Although the skin lesions are often painless, they may be painful. The satellite lesions on the traveler’s skin are useful for clinical diagnosis. The wounds appeared on the skin may be disappeared via self limitation [16].
Sometimes, Leishmania contaminate both skin and mucosal tissues which may lead to cutaneous and mucosal leishmaniasis. The mucosal leishmaniasis is known as self limited infection [16].
Clinical demonstrations of cutaneous leishmaniasis in parallel with diagnostic methods including direct microscopy, culture media, and molecular approaches are useful to detect the infection [16].
Insect repellent ointments, mosquito nets, and wearing clothes are good choices for preventing the appearance of cutaneous leishmaniasis.
Treatment may be done via different antimicrobial agents amphotericin B, and miltefosine [16, 18].
Myiasis
Myiasis is a common disease between vertebrate animals and humans that is caused via larvae of diptera flies [19]. Faruncular myiasis is usually seen in infected travelers which is transmitted by two larvae flies of Cordylobia anthropophage (tumbu fly) and Dermatobia hominis (human botfly) in Africa and Latin America respectively [20]. The causative larvae are able to distribute in different parts of the host’s body. The tropical and subtropical areas are the original places for the infection. The economic and social behaviors of travelers are known as risk factors for myiasis. Myiasis ranks fifth among travelers’ skin diseases around the world [19].
The type of larva is determined factor for clinical symptoms and manifestations of the skin wounds. Generally, the clinical demonstrations are seen within 1-3 weeks on the traveler’s skin [5, 21, 20, 22].
The clinical detection of myiasis is done via detecting the causative larvae in the appeared wounds on the patient skin. To have a definite treatment, surgery is recommended. Also, the antibiotic of ivermectin is suitable for treatment. Disinfection of the myiasis lesions guarantees the prevention of bacterial tetanus [5, 20].
Tungiasis
Tungiasis is an infection which may be seen in the feet skin area of patients. It is caused by pregnant female sand fleas (chigoe fleas, jigger fleas) of Tanga panetrans. The fleas are feeding blood and producing eggs in warm blood hosts (human, dog and etc.). The individuals with bare feet are the most people in the risk for direct contact with fleas in contaminated soil and sand beaches. Tungiasis is a considerable skin infection among travelers who trip to tropical and subtropical regions including Africa, Asia, the Caribbean areas, India and Latin America [20].
The warty nodules and black centered papules with or without pain are usually seen on the skin of patients in a range of a week to 6 weeks after infection by fleas [5].
Clinical skin demonstrations and the morphological properties of the fleas are suitable approaches for laboratory diagnosis of tungiasis [5].
A definite treatment may be done via extraction of the fleas by sterile curettes. The antibiotic prophylaxis is needed for prevention of bacterial infections [5].
Tick bites
Tick as a giant gobbler feeds blood from humans and animals throughout biting. The people who work with animals are in high risk for being bitten by ticks. There are soft and hard ticks; but according to several studies, hard tick are the most important agents for transmitting microbial pathogens via their saliva during each bite. As the tick bites are not painful, there is no alert for notifying patients about disease transmission. Diseases like African tick fever, Rocky Mountain spotted fever, and Lyme are transmitted by tick bites [4].
Lyme disease
Lyme disease is a bacterial infection which is caused by Borrelia burgdorferi; the causative bacteria are transmitted into the human host via the bites of Ixodes. In the most cases, patients have no idea about the way of infection [23].
The areas involving the south of Scandinavian countries, the north of Mediterranean countries, the central and the east of Europe, North and Central America are well known endemic foci for Lyme disease. The rate of infection reports is limited among travelers who are back from their trips [23].
The clinical demonstrations are appeared between 3-30 days with predominant symptoms of rash and erythema migrans. The rash is usually seen with other clinical manifestations of fever, headache, some pain in joints and muscles. The progression of Lyme disease may lead to neurological disorders and cardiac malfunctions [23].
In similar to aforementioned skin infections, the use of repellent agents, wearing clothes and socks are suitable prevention choices for being infected.
The patient history, the clinical skin manifestations such as rashes and serological techniques of ELISA or IFA may help to infection diagnosis. The oral consumption of deoxycycline or the intravenous injection of ceftriaxone are recommended for a definite treatment [23].
Mite
Mite as a small arthropod is fed on different birds, insects, and mammals. The main hosts of mites are recognized as chicken, dog, rat, and mouse). Human is the occasional host for mites. The clinical symptoms of burring and itching are general manifestations in humans caused by mites’ bites as important vectors. For treating the symptoms, the use of antihistamines (oral consumption) and betamethasone ointment are recommended as proper choices [4].
Scabies
Human scabies is an infection caused by Sarcoptes scabiei mite. Scabies demonstrations involve a severe itching. The female mites may lead to infection in their hosts. The immune system in the host shows a hypersensitive allergic reaction on the skin which is due to deposition of the mite eggs’ and its feces. Intense itching appears almost at night [4].
Scabies is seen in infants, children and adults. The scabies symptoms may be observed on different part of the skin, particularly burrowed wounds on wrist, trunk and genitals areas. A severe form of scabies is crusted scabies. The crusted scabies is in association with skin infestation via hundreds of female mites. The clinical manifestation includes confluent crusted plaques on trunk area together with erythema and itching signs. Crusted scabies is generally observed in elder patients and people with defective immune system [4].
Clinical symptoms and direct microscopy of extracted mites from the skin burrows or crusts confirm the presence of scabies [4].
The cream of permethrin 5% or malathion 0.5% lotion are suitable choices for treatment. The topical use of aforementioned agents must be done by the family members and they must be exposed from the neck down [4].
In patients with crust scabies, the oral consumption of ivermectin is recommended. Ivermectin should not be used in young children (under 2 years) and pregnant women.
In parallel with treatment, bed covers and underclothes must be washed. The itchy skin is normally treated in a period of 4-6 weeks [4].
Skin disorders in association with usual systemic febrile illness
Arboviral infectious diseases
Arboviral infectious diseases have been increased throughout the raise up of dengue and chikungunya viruses’ infections among travelers. The both of viral infectious agents are transmitted to humans by arthropods [5].
Dengue virus
Mosquitoes are well known vectors for quick spread of dengue viruses. Today, the expansion of dengue viruses is seen in rural and urban areas of different countries worldwide including Africa, tropical climates of Asia, Latin America, and Mediterranean region [24].
Dengue can be found throughout Central America, the Caribbean and South American countries with large increase in countries with tropical climates. Aedes mosquitoes are vectors of dengue viruses. Dengue fever main symptoms involve a sudden appearance of fever, headache, myalgia, and macular erythema rash. The clinical symptoms are revealed between 2-4 days. Detection of infection must be performed immediately. The serological tests are used for confirming the viral detection [3].
Chikungunya virus
Chikungunya virus is the causative agent of a systemic febrile illness with some skin disorders. The virus vector is Aedes mosquitoes. Previous studies show that chikungunya virus has the same geographical distribution as dengue virus has [25].
There are some similarities between dengue fever and the chikungunya virus disease including sudden high fever and erythematous rash. Therefore, clinical manifestations of the both infections are near to each other. The particular demonstration relating to chikungunya virus infection is polyarthritis which may continue several months with some disability. In few cases, some abnormalities such as heart failure, variable hypertension, acute renal failure, hepatitis, etc. may happen. Complications relating to the infection are more usual in old patients [3].
Diagnostic methods for detecting the viral agent include cell culture, PCR and serological assays [25].
The use of non-steroid-anti-inflammatory and steroid drugs is recommended for treatment [3].
Rickettsiosis and scrub typhus
Rickettsiosis is known as a common zoonotic bacterial infection among travelers. The infection is transmitted to human hosts via arthropod vectors. Rickettsiosis is an urgent disease which is generally accompanied by main sign and symptoms of fever and diffused rash. In some reports, organ failures and mortality in infected people are recorded. A type of rickettsiasis is occurred due to African tick bite fever (ATBF) [26].
The disease is caused by bacterial agent of Rickettsia africae which its vector is the cattle tick of Amblyomma. The infection is endemic in some regions in Africa and the Caribbiean. The reported clinical manifestations involve fever, headache, neck myalgia, scars, and occurrence of maculopapular or vesicular rash [5, 26, 28].
Different types of rickettsiosis ininfected travelers
Rickettsia conorii, the agent of Mediterranean spotted fever is an endemic disease recognized in the Euro-Mediterranean region, Africa and Asia is transmitted via dog bites [5].
Rickettsia typhi, the bacterial agent of murine typhus infection is transmitted via fleas. The infection is distributed in tropical and sub-tropical regions [5].
Rickettsia rickettsii is recognized as the bacterial agent of Rocky Mountain spotted fever which is transmitted by dog bite. The infection is endemic in the American continent [5].
Orientia tsutsugamushi is the causative agent of Scrub typhus which is transmitted via the bites of trombiculid mite larvae. The disease is endemic and distributed in the western pacific and South Asia [5].
Clinical symptoms and serological assays are routine diagnostic approaches. However, PCR techniques are rapid diagnostic method for detecting the microbial agents within scars taken from skin biopsies [5].
Deoxycycline is an appropriate antibiotic for treating adults. The drug is not suitable for children [5].
Conclusion
Skin infections are a considerable health care problem among global travelers. The most reported data are provided from medical centers, which the doctors visit infected travelers turned back from the trips. In the following of detection of clinical manifestations relating to tropical infectious diseases in patients, some questions including the time of travel, visited regions, probable risk factors, and self medication must be asked from them. Travelers must be advised for the types of infectious diseases by medical health center before their trips.