|FACE TO FACE
|Year : 2013 | Volume
| Issue : 2 | Page : 170-174
An interview with Dr. Magda Azab
|Date of Web Publication||26-Nov-2013|
|How to cite this article:|
. An interview with Dr. Magda Azab. Trop Parasitol 2013;3:170-4
Tropical Parasitology (TP): Egypt is a country famous for its ancient civilization. The country also has some interesting history on parasitic diseases. Can you shed some light on the historical aspects of the parasitic diseases of Egypt?
Dr. Magda Azab: Evidence of the existence of parasitic infections in Egypt since Pharaonic times has been extensively documented. Successful amplification of Leishmania donovani deoxyribonucleic acid (DNA) in bone tissue samples of ancient Egyptian and Nubian mummies dating back 4000 years, proved the presence of visceral leishmaniasis. The prevalence of infection in Egyptian mummies was recorded in the Pre- to early dynastic site of Abydos (3500-2800 BC) and in Thebes West from tombs built between the middle and new kingdom until the late period (2050-500 BC). Samples from Nubian mummies were from earlier burial sites at Kulubnarti, from an island in the Nile dating from 550 to 750 AD and from the western bank of the Nile that was in use from ca. 750 to 1500 AD. Transmission to Egypt probably occurred as a result of close trading contacts with Nubia, during the Middle Kingdom.
- Human malaria in Egypt also dates back to the Pharaonic times as shown by:
aDNA analysis, which identified Plasmodium falciparum in ancient Egyptian mummy tissue samples, from about 4000 years ago. Paleopathology of soft-tissue biopsies, of 16 mummifies recovered from the necropolis of Abusir el Meleq (Fayum) dating from the 3 rd Intermediate Period (1064-656 BC) to the Roman period (30 BC-300 AD), substantiated the endemicity of malaria in this area due to the presence of the lake Quarun and to the particular nature of its irrigation system. The presence of malaria antigens was also confirmed in samples from the Marro's Egyptian collection of predynastic mummies (3200 BC) collected from the archeological sites of Assiut and Gebelen (located in Upper Egypt) and maintained at the anthropological and ethnographic Museum of Turin, Italy. Also ancient P. falciparum DNA was identified in mummified skeletons from Thebes-West dating from the new kingdom to the late period (1500-500 BC) and in 18 th Dynasty royal mummies. In addition, the parasite surface protein antigen MSP1 allele was successfully genotyped in three of six malaria-positive mummies. Malaria endemicity in ancient Egypt was related to its proximity to the Nile valley and river flooding producing perfect breeding sites for mosquitoes. Some texts noted the presence of mosquitoes and the use of bed-nets as protection by Sneferu, the founder of the Fourth dynasty of Egypt, who reigned from around 2613 to 2589 BCE and Cleopatra VII, the last Pharaoh of Ancient Egypt, who also slept under a mosquito net. The historian Herodotus (484-425 BCE) wrote that the builders of the Egyptian pyramids were given the large amount of garlic, radishes and onions due to their anti-oxidant qualities, to protect them against malaria and other infections. Although there was no clear description of malaria or leishmaniasis in Ebers Papyrus (20 feet long document dating from the time of Pharaoh Hor-Den, the 1 st dynasty and discovered in 1875, at Thebes) symptoms of enlarged spleen and fever have been mentioned.
- In pharaonic times Egyptians suffered from schistosomiasis despite the lack of perennial irrigation and consequent lack of suitable sites for transmission. Convincing paleopathological evidence for the presence of this disease in mummies, confirmed that schistosomiasis has existed continuously in Egypt for at least 5000 years. Infection revealed in test samples from the skin of a naturally desiccated body of an adolescent (3200 BC) was substantiated by the discovery of calcified ova in bladder, kidney and bowel of the unembalmed 21 st dynasty mummy a 16-year-old Egyptian boy (known as Nakht, the weaver of the funerary temple of the Pharaoh Setnakht" 1184-1181 BC) and who also had taeniid ova in the intestinal tract. A large number of Schistosoma haematobium eggs were demonstrated in microscopic sections of kidneys of two mummies of the 20 th Dynasty; and radiologically in a mummy of a 14-year-old boy from the same archeological period, that was naturally preserved by desiccation. From later periods calcified schistosome ova were identified radiologically in several mummies as well as calcified bladders in two other mummies. The classic symptom of blood in the urine was described in the Ebers papyrus as the aaa disease and mentioned 50 times in various other medical papyri that contain prescriptions against hematuria. Although there is still no evidence that Schistosoma mansoni existed in ancient Egypt there are records of enlarged livers in some mummies; and some tomb paintings of peasants, boatmen, papyrus carriers and other rural people in the Sakkara necropolis show distended abdomens that may be related to schistosomiasis. Later evidence of schistosomiasis in medieval Egypt was in 15 mummies from 35 to 550 AD in the Wadi Halfa riverine area near the Egypt-Sudan border.
- Other worm infections have been documented in Ancient Egypt. The first mention of hydatid disease was in the year 1534 BC, in Ebers' papyrus. This was later authenticated by the discovery of a hydatid cyst in the lung of a mummy belonging to a lady known as Asru who was a chantress at the Karnak temple (dedicated to the god Amun, at Thebes) during the 3 rd intermediate period (1000-700 BC). X-ray images of her bladder revealed clear calcifications indicating that she also suffered from schistosomiasis. Evidence of Strongyloides stercoralis infection was found in the Asru mummy. In a mummy from ptolemaic period (second to first centuries BC) a cystic lesion in the stomach wall proved to be cysticercus cellulosae, the larval stage of Taenia solium. The use of pomegranate was mentioned in Ebers medical papyrus for the eradication of tapeworms. There is a record of Ascaris lumbricoides in a Middle Kingdom Egyptian mummy dating from 1938 to 1600 BC. Pinworms were also recognized and correctly described in the papyri. The earliest descriptions of Dracunculus (Guinea worm disease) from the Ebers Papyrus include instructions for treating aat swelling in the limbs. The discovery of a well-preserved female worm and a calcified worm in Egyptian mummies confirms the presence of this worm in ancient Egypt. One particular disease that attracted the attention of the Ancient Egyptians is elephantiasis due to lymphatic filariasis. The characteristic grotesque swellings of the limbs, breasts and genitals were described and depicted in ancient drawings. The swollen limbs of a statue of the Egyptian Pharaoh Mentuhotep II from about 2000 BC suggest that he was suffering from elephantiasis. An autopsy on the 3000-year-old mummified body of Natsef-Amun, a priest during the time of Ramses XI, revealed the presence of filarial worms. Another interesting record is in a relief on one of the walls of the mortuary temple at Deir el-Bahri (Djeser Djeseru) across the Nile west of Thebes, showing scenes of a seaborne trading expedition to the land of Punt (probably nowadays Somalia) ordered by Queen Hatshepsut (ca. 1508-1458 BC), the fifth pharaoh of the 18 th dynasty of Ancient Egypt. In the relief is a realistic depiction of the Queen Iti of Punt, with what I personally recognized as elephantiasis of one leg. Due to folds of fat hanging over her knees and elbows and a crooked back some researchers believed that she suffered from a genetic trait called steatopygia.
- A huge variety of insects was recorded by the ancient Egyptians. Those of medical importance included mosquitoes, fleas and bed bugs. A blood sucking louse (transmitter of typhus) was found in a sample of human hair from Abydos (3000 BC). Some insects were given names as py (flea), aff (fly), xmy (sandfly) and others were depicted in hieroglyph design as the bee () and fly ().
TP: How would you assess the present scenario of parasitic diseases in your country?
Dr. Magda Azab: Of the disease previously mentioned malaria has been practically eradicated from Egypt and since 1998 there have been no officially reported autochtonous cases in the Fayum Governatorate or elsewhere in Egypt. Prevalence of schistosomiasis has declined in Middle and Upper Egypt and in the Nile Delta. Though controlled due to large-scale chemotherapy and effective early treatment, prevalence of schistosomiasis today is about 20% in the Egyptian population and up to 85% in some of the small villages. Although consequential in Fayoum, S. mansoni is rare in Upper Egypt and has almost totally replaced S. haematobium in lower Egypt; a situation possibly related to the introduction of Biomphalaria glabrata in the south of the Nile Delta and in the north-central Nile Delta. This was complicated by the appearance and spread of hybrids between B. glabrata and the indigenous Biomphalaria alexandrina throughout the Nile Delta. Lymphatic filariasis was endemic in certain localities in Egypt with focal distribution in clusters of villages especially in the governorates of Qalyubiya, Monufiya, Dakhaliya and Giza. Interruption of transmission with drugs that target microfilariae was attempted. A mass drug administration program based on World Health Organization's (WHO's) strategy of repeated rounds of administration with diethylcarbamazine and albendazole (target population, 2.5 million in 181 localities) completed five rounds in Egypt. As a result lymphatic filariasis has been eliminated from most areas of Egypt. Strongyloidiasis is endemic in some foci of Menoufiya governorate. It is frequently underdiagnosed because many cases are asymptomatic except in occasional susceptible immunocompromised and handicapped individuals. An outbreak of trichinosis in the 1990's was quickly aborted by the implementation of successful control measures at the reservoir hosts level. Since most other parasitic helminthic and/or protozoan diseases are not notifiable diseases in Egypt epidemiological information is sporadic and comes from individual research efforts. Accurate epidemiological information concerning hydatidosis, fascioliasis, ascariasis, amebiasis, giardiasis and coccidial parasites in human is lacking, but sporadic cases are continuously encountered. While cutaneous leishmaniasis caused by Leishmania major is endemic in the Sinai region, transferred to humans from infected rodent reservoir hosts (Meriones crassus and Gerbillus pyramidum) by the bite of the sand fly vector Phlebotomus papatasi, Egypt is not a known focus for Leishmania tropica. Infantile visceral leishmaniasis was documented in the outbreak in Egypt mainly in Al Agamy, Alexandria during the early 1990s.
TP: In what way the epidemiology of parasitic diseases of Egypt different from that of Sub-Saharan Africa?
Dr. Magda Azab: The difference in epidemiology lies in the endemicity of malaria, African trypanosomiasis and leishmaniasis among the people of Sub-Saharan Africa causing many deaths. Suitable factors of abundant breeding areas for specific vectors (Anopheles spp., Glossina spp. and Phlebotomus spp. respectively), absence of sophisticated water and sanitation systems and the digging of canals or ditches for irrigation contribute to making the burden of these diseases and mortality highest in some of the poorest areas of sub-Saharan Africa. This continent bears over 90% of the global P. falciparum burden, accounting for almost all malaria mortality. According to the WHO's 2011 World Malaria Report, the countries with the five highest numbers of reported malaria deaths for 2010 are: Kenya (26,017), Democratic Republic of Congo (23,476), Tanzania (15,867), Burkina Faso (9,024) and Uganda (8,431).
Human African trypanosomiasis, also known as 'sleeping sickness, occurs in 36 countries of Sub-Saharan Africa with over 60 million people at risk, due to the exclusive presence of tsetse flies-transmitters of the disease. Populations mostly exposed to the tsetse fly and therefore the disease, are those living in rural areas and depend on agriculture, fishing, animal husbandry or hunting. Trypanosoma brucei, Trypanosoma gambiense found in 24 countries in west and central Africa, accounts for over 98% of reported cases of sleeping sickness and causes a chronic infection. T. brucei, Trypanosoma rhodesiense found in 13 countries of Eastern and Southern Africa, represents under 2% of reported cases and causes an acute infection. Visceral leishmaniasis occurs in Sudan, South Sudan and Ethiopia while cutaneous leishmaniasis is in Ethiopia and North Sudan.
TP: What are the current priorities of parasitic research in Egypt? Which parasitic diseases in Egypt do you think would need more attention on research?
Dr. Magda Azab: Research efforts are directed to dealing mostly with indigenous parasitic infections covering different aspects of epidemiology, pathogenesis, immunology, updated diagnostic techniques concerned with emerging and re-emerging parasitic disease and their bioinformatics, food and waterborne parasitic diseases, as well as novel therapeutics. The general trend is for molecular mechanisms, genotyping, proteomics and lately the application of nanotechnology and stem research.
Schistosomiasis still requires more research especially in relation to search for herbal or biochemical cysteine protease inhibitors substitutes for established therapies presenting some resistance as praziquantel. As well as proteomic approaches to identify and characterize the major glycoproteins of schistosome worms and cercariae, that may represent novel targets for pharmacologic intervention of cercarial invasion and possible vaccine candidates.
TP: How are the research activities in parasitic diseases in Egypt in terms of technicality and quality in comparison to the developed countries of the West?
Dr. Magda Azab: Although molecular biology research is now applied in many specialized laboratories in most Universities and Institutes, applied sequencing, proteomic and stem cells studies are still deficient.
TP: As one of the founders of the Egyptian Parasitologists United (EPU) association, can you brief us about the motives of the EPU?
Dr. Magda: Basically, EPU was founded in 2007 with the aim of uniting Egyptian Parasitologists efforts as regards their biography, education, research and training, achieved by the organization of scientific conferences, seminars and workshops.
EPU supports research efforts in the different fields of Parasitology dealing mostly with indigenous parasitic infections covering different aspects of epidemiology, pathogenesis, immunology, updated diagnostic techniques concerned with emerging and re-emerging parasitic disease and their bioinformatics, food and waterborne parasitic diseases, as well as novel therapeutics. Nanotechnology and its impact on Parasitology, Parasitic Diseases in "Omics" Era and evidence-based medicine are supported. Because EPU is constantly examining ways to improve the fulfillment of its mission and challenge all obstacles to set new standards of excellence and ever striving for improvement of quality the 3 rd conference of EPU on 11-12 October 2012 advocated: (1) An outline for the classification of parasites affecting humans titled " toward a unified taxonomy of parasites", acceptable to all Medical Parasitology Teaching Universities and Institutes in Egypt. It was decided to follow the classical classification for helminthes and the "super groups classification" approach for protozoa. (2) Prophylaxis against side-effects and complications of eating Fasciola infected animal livers even when well-cooked to avoid hazardous toxemic effects. (3) The encouragement of future research on the effect of global warming on the epidemiology of parasitic infections in our environment. (4) The encouragement of future research on the validity of nanoparticles as vehicles for treatment regimens.
TP: What are the current national policies in Egypt for the prevention and control of parasitic diseases? How efficient are these policies and what are your suggestions for their improval?
- Dr. Magda Azab: As reported by WHO-tropical disease research (report no. 15) a schistosomiasis vaccine development program, based in Egypt and supported by United States agency for international development, focused on two S. mansoni antigens as possible vaccines candidates: Paramyosin and a synthetic peptide construct containing multiple antigen epitopes from the triose phosphate isomerase (Bachem Company, Los Angeles, USA). However, results obtained indicated that these candidate vaccines only provided partial reduction in challenge-derived worm burdens relative to non-immunized controls. It is hoped that better success can be achieved using cocktails of recombinant antigens.
- A follow-up epidemiological assessment to determine whether the large-scale mass treatment pioneering campaign has been successful in finally eliminating the disease.
TP: What initiatives have the medical council taken in expanding / improving research in parasitology in Egypt?
Researchers apply to the Egyptian Science and Technology Development (STDF) that offers funding for different projects: STDF Technology Incubator Program; Faculty for Factory Program-Industry Call for Proposals; Innovation Grants ; STDF Short Term Fellowship; Young Researcher Grants; Reintegration Grants .
TP: What are the long term goals of your association in eliminating the parasitic burden in your country?
The promotion of a campaign for prophylaxis against toxoplasmosis since despite being a readily diagnosed and treated disease, toxoplasmosis is not a reportable infection and its control has received no emphasis from public health zoonotically transmitted diseases control programs. It was thus suggested to grasp the opportunity and target undergraduate and postgraduate students in all faculties and institutes, for the implementation of a campaign to control transmission of toxoplasmosis. By stressing upon these medically aware students the importance of serological screening, especially antenatal for females, would be one way of serving the purpose of control. All male and female students should be encouraged to start by themselves and their female relatives, to be tested for seropositivity in order to avoid the possibility of acquiring the infection during pregnancy; and if negative then they should be counseled on how to protect themselves if and when they should become pregnant. This promotion of awareness among medical students would be like producing ripple waves of knowledge in the community emphasizing on the importance of controlling toxoplasmosis in a campaign of no cost.
TP: What are your recommendations for implementation in National programs for eradication of parasitic diseases?
- Dr. Magda Azab: To lay the foundation for future epidemiological studies in Egypt there is an urgent need to establish a local database to include and compare data pertaining to the different aspects of research on prevalence, treatment and resistance to treatment and the development of better methods of prevention and diagnosis of parasitic diseases. Any available Egyptian recordings of prevalence and/or incidence are due to individual personal efforts by researchers in the different governorates or areas.
- Global warming and host-parasite interaction is an important epidemiologic issue to face in the coming years. Parasites will undergo adaptive changes and host populations and their ability to overcome disease transmission will accordingly change. Estimation of the affect of long-term warming on the distribution of the different parasites is a challenging task that requires the preliminary determination and quantification of present data and future expectations. To attain detailed analyses, basic mathematical models of factors affecting population dynamics of parasites are needed. Programs are needed for mapping the local distribution of parasites in the Egyptian environment, in order to monitor their tolerance to climatic change, which will lead to areas in which parasites will persist and areas in which they will infect new hosts. Proper seasonal studies of parasites distributions are needed to record baseline data related to seasonal temperature changes in order to attain quantitative parameters of the expected affect of climate change on the distribution of parasites in our Egypt. Through established models, the statistical distribution of parasites within the host population can be determined. The basic outlines of examination should include: Modes and routes of infection; life cycles (monoxenic with infective stages that directly infect other susceptible definitive hosts and heteroxenic involving a number of intermediate hosts or vectors); hosts (definitive, intermediate, reservoir); endemic areas and other areas prone to parasites spread into new hosts.
- A follow-up epidemiological assessment will reveal whether the large-scale pioneering campaign of mass drug administration program has been successful in finally eliminating lymphatic filariasis.
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