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Onchocerciasis is a leading cause of blindness in the world. It may be seen in temperate climates of the United States and Europe in immigrants and travelers from endemic regions, often linked to poverty and war. One should be aware of an incubation period that can be up to 15 months. In its early stage and throughout its course, onchocerciasis has noteworthy skin findings, facilitating diagnosis, as onchodermatitis resembles common eczema with variable degrees of papular, lichenoid, atrophic, and pigmentary alterations, features not suggestive if one is unaware of an individual's immigration and travel history. The same concept applies for the encysted worms (onchocercomas), as they tend to appear as common skin cysts and benign neoplasms. New methods can be employed to increase diagnostic sensitivity and specificity. Ivermectin is the gold standard of therapy, the use of which has almost miraculously eliminated this disease from large areas of the earth. However, its effect remains isolated to microfilariae and can be devastating in those coinfected with Loa loa. Recently, the symbiotic relationship between adult worms and Wolbachia bacteria has been discovered and, with it, the possibility of adding doxycycline as a treatment option. We also discuss coinfection with HIV and other diseases., (© 2019 The International Society of Dermatology.)

Yemen is a country that has been treating severe cases of oncho-dermatitis since 1992 and is now moving to a program aimed at the elimination of the transmission of Onchocerca volvulus . It is important to ensure that the currently acceptable tools used in epidemiological assessment of onchocerciasis in Africa and Latin America also apply to Yemen. Five hundred and ten blood samples from three known O. volvulus -endemic areas, locations that have never been under a mass treatment program, were tested for the presence of antibodies against a panel of O. volvulus -specific antigens using enzyme-linked immunosorbent assay (Ov16) and luciferase immunoprecipitation system (Ov-FAR-1 and Ov-MSA-1) assays. Overall, 31.4% of the samples tested were positive, with positivity increasing with age. Positivity was seen in 76.5% of those presenting with clinical onchocerciasis but importantly also in more than 28.5% of those defined as free of oncho-dermatitis; these latter individuals are likely to be serving as a source for persistent reinfection. This study supports the use of the current O. volvulus -specific serologic methodology in Yemen.

The onchocerciasis focus in Yemen has been known for many years as an endemic area with unique characteristics, notably the atypical and most severe form of onchodermatitis, known as sowda or reactive onchodermatitis (ROD). The national effort to control the disease began in 1992 as an individual case treatment program by administering ivermectin to those presenting with ROD. The challenging geography of the endemic area and the current political and military unrest both underscore a need for special approaches when attempting to eliminate onchocerciasis from this country. An assessment of the national situation regarding this disease was carried out in 2011-2013 aimed at defining the best approach for moving from individual clinical case treatment to elimination of transmission. The history of the control efforts and the current status of the disease are reviewed and the essential changes needed to a mass drug administration (MDA) approach are identified as the national program addresses elimination. Yemen, despite the current troubles, has shown that it can successfully implement MDA programs despite many difficulties and therefore should be supported in its efforts towards countrywide elimination of this infection; however, success will need renewed national and international efforts.

Leprosy is a chronic human disease caused by the yet-uncultured pathogen Mycobacterium leprae. Although readily curable with multidrug therapy (MDT), over 200,000 new cases are still reported annually. Here, we obtain M. leprae genome sequences from DNA extracted directly from patients' skin biopsies using a customized protocol. Comparative and phylogenetic analysis of 154 genomes from 25 countries provides insight into evolution and antimicrobial resistance, uncovering lineages and phylogeographic trends, with the most ancestral strains linked to the Far East. In addition to known MDT-resistance mutations, we detect other mutations associated with antibiotic resistance, and retrace a potential stepwise emergence of extensive drug resistance in the pre-MDT era. Some of the previously undescribed mutations occur in genes that are apparently subject to positive selection, and two of these (ribD, fadD9) are restricted to drug-resistant strains. Finally, nonsense mutations in the nth excision repair gene are associated with greater sequence diversity and drug resistance.

The diagnosis of leishmaniasis can be challenging because it mimics both infectious and malignant conditions. A misdiagnosis may lead to an unfavorable outcome. Using culture, histologic, and/or polymerase chain reaction study results, a diagnosis of leishmaniasis can be established and treatment initiated. Appropriate management requires an accurate diagnosis, which often includes identification of the specific etiologic species. Different endemic areas have varying sensitivities to the same medication, even within individual species. Species identification may be of practical value, because infections with select species have a substantial risk of visceral involvement. In addition, HIV and otherwise immunocompromised patients with leishmaniasis have a propensity for diffuse cutaneous leishmaniasis. For most New World Leishmania species, parenteral antimonial drugs remain the first line of therapy, while Old World species are easily treated with physical modalities. Historically, live organism vaccination has been used and is effective in preventing leishmaniasis, but results in an inoculation scar and an incubation period that may last for years. A more effective method of vaccination would be welcome., (Copyright © 2014 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.)

Leishmaniasis is endemic in 98 countries and territories, with 1.2 million new cases per year, making it a worldwide concern. The deadly visceral form is a leading cause of death from tropical parasitic infections, second only to malaria. Leishmaniasis appears to be increasing in many countries because of extended urbanization. The disease reservoir includes small mammals; parasite transmission occurs via bite of the female phlebotomine sandfly. Disease manifestations vary and largely depend upon the Leishmania species acquired. It may be first evident with a range of findings-from a localized cutaneous ulcer to diffuse painless dermal nodules-or, in the mucocutaneous form, ulceration of the oropharynx. In the potentially deadly visceral form, the internal organs and bone marrow are affected., (Copyright © 2014 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.)

Leishmaniasis is a widespread parasitic disease seen most often in children and young adults, although it may occur at any age. In Yemen, up until now, specific treatment for cutaneous leishmaniasis (CL) has been challenging. Available chemotherapy is expensive and replete with significant side effects. Standard cryosurgery with liquid nitrogen is prohibitively expensive and often unavailable. The objective of this paper is to highlight the importance of cryosurgery with carbon dioxide slush in the treatment of CL in an economically underdeveloped region as a cost-effective, simple, successful, and affordable option., (© 2012 The International Society of Dermatology.)

Lymphatic filariasis (LF) is targeted for worldwide elimination. In Yemen, all mainland implementation units met the WHO criteria for stopping mass drug administration (MDA) after 5 rounds. However, in Socotra Island these criteria were not met. Our study evaluated the efficacy of applying expanded polystyrene beads (EPBs) on the Culex population and the effect on LF transmission. Human and mosquito surveys were conducted in 40 randomly selected households in Hadibo (capital of Socotra) before and after application of EPBs. The EPBs intervention resulted in a reduction in mosquito density of 80% and a 64.3% reduction in microfilaria prevalence. The majority of interviewed households (98%) thought EPBs considerably reduced the mosquito population. After the intervention all collected pools tested negative. Application of EPBs is an effective supplement to MDA for achieving the goal of LF elimination.

Although the prevalence rate of leprosy in the Republic of Yemen has dropped below the WHO elimination level of less than one case per 10,000 of the population, it is still regarded as a serious public health problem calling for continued vigilance, notably in the detection and treatment of hidden and undiagnosed cases. In the past, religious misinterpretation has generated adverse behaviour patterns towards people affected by leprosy, characterized by aggression, negligence and isolation. Until about 1982, following a visit of a leprologist (Dr S. K. Noordeen) from the World Health Organization, there was no leprosy control programme and attempts to establish one remained ineffective until in 1989, when an agreement was signed between the Ministry of Public Health and Population and the German Leprosy Relief Association. This led to the development of a leprosy control programme in four governorates, later extended to the rest of the country. This paper describes the progress made in the control of leprosy in the Yemen, 1989-2003, by the Ministry of Health and Population and the GLRA, in association with two local societies.

The geophysics of the north Yemen, associating a north-south directed mountainous fish bone (rising in more of 2,000 meters), to numerous rivers or "wadis" is convenient to the development of simulium shelters, main vectors for cutaneous filariasis to Onchocerca sp. Following several missions of bio-clinical and epidemiological evaluations in neighbouring villages of wadis, it has been possible to study different clinical aspects: one reminding the classical african onchocerciasis with generalized and diffused dermatitis, and, on an other hand, a hyperreactive dermatitis on one side of the body and associated with a collateral lymphatic ganglion. This disease is well known for local populations as "aswad" meaning "black" or "sowda". Clinically whatever the studied focus, coexists the two types of onchodermatitis (uni or bilateral). Yhe sowda patients are proportionally less numerous than those touched by the generalized type. Frequent eye lesions of the West African onchocerciasis are not found in sowda cases. In classical optical microscopy, microfilaria is morphologically indifferenciable between sowda and onchocerciasis clinical aspects. Skin snips were carried out on patients of both groups. Identification of microfilaria by molecular biology through the study of the DNA genome was done out of 5 skin snips. Microfilaria was kept dry between laminas and the DNA extracted from rehydrated microfilaria. DNA was intensified with specific primers of Onchocerca type (O150PCR). This phase was followed by hybridisation of amplification products by PCR to specific stains: OVS-2 for Onchocerca volvulus species, OCH for Onchocerca ochengi, PFS1 and PSS1-BT respectively for the forest strain and the savannah strain of Onchocerca volvulus as described previously. We can distinguish 2 kinds of answers based on the clinical origin of the snip-tests: the first one concern 3 patients with numerous dermal microfilariae but without any clinical sowda and corresponding to microfilaria O. volvulus type but different from the forest or savannah strains found in sub-Saharan Africa. The second one corresponds to 2 patients with less than 5 microfilaria in their snip-test. They show the typical clinical picture of sowda. They are identified as microfilaria type Onchocerca but they do not belong to species volvulus, or to species ochengi. It seems quite probable that the clinical picture of sowda be the result of developing onchocerciasis of animal origin and not identified as to day. The ivermectin, therapeutic of choice for African onchocerciasis in annual unique cure seems less effective in the coverage of sowda. In that case rehearsal of cures every 3 months would be necessary for mass campaigns to limit the transmission of this filariasis.

Introduction of dapsone therapy paved the way for better and more humanitarian way of dealing with the leprosy victims who, prior to 1943, were simply rejected and segregated from society. Emergence of dapsone-resistant M. leprae and mycobacterial persistence provoked our quest for another solution. More drugs were discovered for treatment of leprosy. But the real breakthrough was the recommendation of regimens of multidrug therapy (MDT) for the treatment of leprosy by the WHO Study Group on Chemotherapy of Leprosy in October 1981. Subsequent world wide development of leprosy control activities was phenomenal. The impact of MDT has led to the cure of over eight million leprosy sufferers and the saving of one million patients from becoming crippled. Leprosy prevalence has decreased by 80% in ten years. By the end of May 1999 the leprosy burden remained concentrated in only 12 countries of the world. These achievements are mainly attributed to the development and worldwide adoption of the MDT programme.

Leprosy control activities in Yemen are reviewed historically and up to the present time. Since 1983 the World Health Organization's multidrug therapy has been used in the National Leprosy Control Programme. Current activities are carried out in 63 leprosy clinics distributed all over the country and staffed by trained primary health care workers and medical assistants. In Yemen leprosy prevalence has declined from 1400 per 10,000 population in 1990 to 647 in 1997. Over the same period, new case detection rates per 10,000 population increased from 185 to 517. A backlog of leprosy cases continues to transmit the disease in Yemen.

Background: Leprosy has been prevalent in Yemen for many years. The ostracization and stigmatization of leprosy patients are well documented in the yemeni literature. No control activities were carried out until 1980., Aim: To document the development of leprosy control activities in the Republic of Yemen during the period from 1982 to 1996., Materials and Methods: The dermatologists in Yemen used various methods, including the media, to fight the stigma of leprosy and thus to mobilize the community for the reintegration of leprosy patients. They sought support from international non-governmental organizations (NGOs) to start mobile teams all over the country., Results: The support of the German Leprosy Relief Association (GLRA) and the World Health Organization (WHO) enabled the National Leprosy Control Program (NLCP) to reach people in remote areas. The prevalence of leprosy has declined from 1.9 per 10,000 population in 1989 to 0.5 per 10,000 population in 1996., Conclusions: The stigma associated with leprosy also extends to other skin diseases. To combat this stigma, various methods, such as health education, training of medical personnel, and mass treatment for skin diseases, have been used.

Sowda skin lesions are of medical and social importance in Yemen. Ivermectin (Mectizan) chose as a control strategy plan in onchocerciasis is active during 3 months for the less on clinical and histological data. After a short increase of itching and oedematous skin aspects clinical signs decrease. Some patients notice an itching rebound after 90 days. Histologically, localized ingratiates, presence of mononuclear cells and melenin loaded histiocytes and eosinophils decreased. The rythm cure has to be studied on a longer period but 3 to 6 months repetition between oral treatment with 200 micrograms/kg dose during two years could be effective.

A review of the case files of 194 leprosy patients registered at a representative skin and venereal diseases out-patient clinic was done to assess the epidemiological and clinical patterns of the disease in Yemen. Almost all patients came from the poorer social groups and there was clustering of patients around some families. About 55% of the patients were aged 20 to 39 years and about 35% were aged over 40 years at the time of detection. Males were affected about three times as females; in males MB cases occurred about twice as often as PB cases and 12% of the cases presented as pure neuritic leprosy. Reactions were noticed in 39 cases (20%), six having type 1 and 27 having type 2 reaction. Bacterial index (BI) among 123 positive cases ranged from 0.1 to 6, about 70% of these cases showing mean BI of more than 2.0. Patients' response to treatment (MDT) was very good and BI decreased by about 1.55 (+/-0.05) logs per year. About 50% of the patients had some disability (14% grade 1), and the disability rate among PB cases was about 70%. Our findings indicate the need for earlier diagnosis and better disability preventive measures.