INTERVIEW WITH THE EDITOR OF TROPICAL PARASITOLOGY

This is the e-mail interview of mine by the Editor of Tropical Parasitology where I have been able to express my views on Parasitic Diseases in India

FACE TO FACE WITH DR MC AGRAWAL

Dr Mahesh Chandra Agrawal , born on 2^nd January,19943 at Firozabad,UP ,obtained university Gold Medals in BVSc & AH, MVSc (Parasitology) being stood first in Jawaharlal Nehru Krishi Vishwa Vidyalaya ,Jabalpur ,MP .He completed his Ph.D. program from JNKVV under ICAR senior fellowship. His main research interests have been schistosomes and schistosomiasis and has been awarded Gold Medals etc by various societies for his outstanding achievements. He was awarded National Fellowship by ICAR, New Delhi (1995-2000) to work on schistosomiasis which happened first in JNKVV and first in Parasitology and after retirement in 2005 he was awarded Emeritus Scientist award of ICAR to work on control of schistosomiasis under field conditions . He is elected fellow of National Academy of Veterinary Sciences, Indian Association for Advancement of Veterinary Parasitology ,Zoological Society of India. Recently his book “Schistosomes and schistosomiasis in South Asia (ISBN 9788132205388) has been published by Springer India Pvt Ltd, New Delhi. Presently, he is busy in writing  a book “Research As Career” for research scholars in Parasitology. In 2012, Prof MC Agrawal has delivered Dr SC Parija oration award of Indian Academy of Tropical Parasitology at Shri Auribindo Medical Institute ,Indore.

1.Parasitic diseases have long been branded as the diseases of developing and the under-developed countries .You have been one of the pioneers in parasitic research in India. Over the period of your long career ,have you noticed  any gross change in trend of these diseases ?

Yes! A great change in trend of these diseases is observed over the time. I think there are two reasons for this. One is the spread of our knowledge on the subject hence we become more aware about existence of diseases  in our location. Second might be the change in environment , irrigation facilities, deforestation ,husbandry practices ,change in vector population etc  that might have contributed in spreading these diseases to new locations .

 2.How has research in microbiology and Parasitology changed in past years in terms of technicality and quality? Are the current studies better designed and better funded than those of yester years ?

There is a tremendous change observed in research pattern of yester year and of present day. When I joined my research career in Parasitology, that was the era dominated by reporting of occurrence or  morphology description  or  life cycle of the parasite. It was fascinating to record a parasite in any unusual host or at unusual location.  However, this was also the period of realization that time is changing and persons were shifting to fields like epidemiology, environment, pathology, biochemistry, immunology, chemotherapy of parasitic diseases (till that time biotechnology has not emerged). Present research is better designed and funded than yester years.

3.How would you assess the present scenario in tropical Parasitology research in India ? Are the Indian laboratories well equipped in performing newer molecular, genomic and proteomic studies in par with the west ?

In my opinion, the present scenario of research in tropical Parasitology in India is not good . We have failed to attract talents in Parasitology and as such research on parasites in zoology departments is diminishing or rather finished  ; neither there is any Master’s program in Parasitology in any zoology department in India nor there is any demand from students. So is the case with Medical faculty .This is all because we have failed to create job opportunities for our young talents in this field.

The contrast to west may be assessed by the fact that many European colleges, where parasitic diseases is not the problem, are running successfully Master’s and Doctorate programs in Parasitology with international research projects . Our laboratories are not as equipped as west for research on tropical Parasitology. But this will be a costly proposition hence I will suggest to have more national and international collaborations for obtaining better results at lower costs .

4. Which parasitic diseases in India you think would benefit most from research and which of the diseases need more attention on research ?

Obviously , the parasitic diseases which are affecting larger population or more animal species need our attention most. We may give our priority to those parasitic diseases which are affecting our tribal population, below poverty line persons ; or parasitic diseases of swine ,sheep ,goat as they are maintained by most poor people.

However, one fact should always be remembered while dealing parasites. They are having complex life cycle , having greatest capacity of modifications as per circumstances ( inheriting sexual life cycle passes this quality due to cross transfer of genes) and its difficult to eliminate them without studying their complexities ; mosquito is the best example which is surviving from thousands of years and have withstood well to all our insecticides and other scientific efforts to eliminate this enemy of human life.

Again change of environmental conditions , local fauna and human activities are leading to emergence of new parasitic problems or some old one may emerge as more problematic hence we should continuously remain watch full on emerging parasitic diseases as well.

5. Are the diseases which are branded as neglected tropical diseases really neglected in India ?

To get the answer of this question, it’s better to examine what the government has done to control these neglected diseases?  There are three fronts- education ,policy decisions and execution side. The education of parasitology is imparted in three faculties-zoology, veterinary and medical . Parasitology has completely been ignored now in zoology departments and no zoology department in India is offering MSc or Ph.D in Parasitology. No state medical colleges are having separate department of Parasitology but it’s a small and neglected part of department of Pathology .Veterinary colleges are having separate departments of Parasitology but the faculty positions are curtailed. No job opportunity is created in this discipline in any of three faculties to attract the talents.

I am not aware if important policy decisions either by planning commission or at government level  have been made along with implementation program to control parasitic diseases in the country ,leaving aside malaria. There is no scientific panel  who may advise the government/departments on important parasitic diseases and how they may be dealt in the country. Neither public health department nor animal husbandry department  has created subject specialist posts on parasitic diseases to control the infections. The parasitic diseases are tackled by either a veterinarian or medical officer with no superior post of  parasitologist in either department.

These facts reflect how parasitic diseases are neglected in the tropical country like India. To avert the situation there is a need of a National Institute of Parasitology (more details given in “The Para Sight issue 2 of IAAVP or see my blog )  which can monitory parasitic diseases of the country.

6. Veterinary Parasitology is a highly neglected field in our country. Considering the large zoonotic reservoir in India, what do you think on the effectiveness of control of parasitic zoonosis in India ?

You are right in saying that parasitic diseases of animals in India have completely been neglected.  Perhaps this is on the notion that they do not cause animal death hence harm to animal industry is minimum. However, sincere  efforts of Parasitologists have conclusively demonstrated that parasitic diseases are not only causing debility or production losses but are also responsible for causing slow ,steady death of animals, one by one, without confirming diagnosis hence specific treatment resulting in wiping of almost whole flock within a short period ; this has been demonstrated well in ovine haemonchosis as well as in ovine schistosomiasis . This neglect is again despite that parasitic diseases neither have any vaccine to control nor have specific drugs like antibiotics for effective cure.

Parasitic zoonosis has two main components- medical and veterinary. How we can effectively control them when both are working wide apart . There is no body which can collaborate  the efforts of the two or any organization which may formulate working plan and combine the work for more efficient results. Earlier, attempts were made to start degrees in Veterinary Public Health but absence of creating posts and a common strategy distracted the concerned persons.

As zoonotic diseases, viral ,bacterial, fungal, protozoan ,helminths make a large part of infectious diseases, it may be better to formulate a separate entity at government level which may deal all these zoonotic diseases by incorporating subject matter specialists of each discipline.

7. Can you share some of your interesting observations of animal infections rarely infesting humans ?

During teaching course of parasitic zoonosis to postgraduate students, I asked the PG students to examine stools of  hostel students for parasitic infections. These hostellers  were found positive for Hymenolepis eggs ; it was later observed that the flour is mixed with positive rat faeces resulting in such infections. Some students ,having rural back ground, were positive for hookworm infection. This simple work showed how parasitic infections may reflect back ground history of any one .  

8.Commending your authorship in various literary materials on helminthes in India, kindly shed some light on the burden of helminthes in our country, comparing the urban ,rural and the tribal population.

As parasitic disease is the cumulative effect of social status , economic activities, nutritional status, behavioral differences and environment  of human population ,so it will naturally differ as per these parameters. Urban group is in advantage stage as it has created conditions where exposure to parasitic stages become minimum hence malaria has remained ,perhaps, the only main problem of this elite group . However, urban population ,particularly, slum dwellers are facing some more problems like amoebiasis. Another problem arising is because of street dogs and their scattering faecal material which is responsible for serious zoonotic diseases like hydotidosis ,cysticercosis, toxocariasis or visceral larval migrans (not mentioning rabies as being a viral problem).

Rural population facing great problems and you may encounter all the parasitic problems ,referred in our text books but severity of problem may differ as per above factors. Thus hookworms ,causative agent for anaemia, are causing havoc to rural pregnant woman and malnourished children . Filariasis, visceral larva migranes , cercarial dermatitis, hydatidosis, cysticercosis, are increasing health problems of rural population and its difficult to escape from these infections due to existing environmental conditions.

Though we have started talking separately about tribal health, it appears ,in my opinion, of little value. Are we knowledgeable about their health problems or infectious diseases common in them ? How many books/publications have come out dealing with tribal health in India ?   .Can be make a generalized statement for the infections for all the tribes , existing in the country, with so much diversity ? ; have we started accumulating data about tribal diseases ? ; have we made epidemiological studies comparing tribal differences ,responsible for particular ailment ?. When we talk about tribes, we have to separate them in various  categories (e.g education ,food habits, occupation, environment ,living in isolation ) to draw fruitful results.

I am aware about the Regional Medical Research Center on Tribal Health, operating at Jabalpur ,Madhya Pradesh. They are working on malaria, tuberculosis, florosis etc but not sure if they are collecting data on general tribal infections and all the details , thereof . As my state, Madhya Pradesh, is possessing large tribal population, I am aware that our remote tribal populace is averse of contacting modern Allopathic doctors and still depend on their home healer or “Ojha” or Gunnia”. Therefore, we have to work much more for knowing their specific  health problems and solutions which may be accepted by them. Their close association with their animals like swine ,dog ,poultry  exposes them more to zoonotic diseases. Moreover, they are still more close to forest ,therefore, infections like schistosomiasis, paragonimiasis, trichinellosis , angiostrongylosis etc can attack them with more probability.

Though I am not loaded with the data, I presume that our tribal population is more severely affected with parasitic infections, looking to their social behavior ,education,  economic conditions, nutritional status, bad surroundings;  moreover, a simple ailment, curable with the help of modern medicine (e.g. hookworm infection) may be dangerous to them due to ignorance and their no reach to the modern medicine.

9. We applaud you for your extensive contribution to research in schistosomiasis. Can you brief us on the magnitude of this problem in India ?

The infection appears a great problem in rural population throughout India but more so where rain fall is high and persons are still depended on tanks, water ponds for their domestic requirements. However, if you will follow western style by searching positive snails in the rivers ,streams , searching egg positive human samples by routine faecal and urine examination, you will ,in all probability, get negative results. This is because the intermediate hosts of Indian schistosomes are present in ponds ,tanks and not in rivers and eggs are extremely difficult to detect in human excreta due to very low egg production. Moreover, the sufferers are generally persons below poverty line like washer man ,fisherman ,cultivators, laborers ,shepherds ,  children, young girls who are most neglected strata of the society. There is another category of possible positive persons- immune-deficient, tuberculosis positive ,malnourished  and alike groups.

The real magnitude of the problem can be judged only when we include above category of persons in our study and start examining them not for schistosome eggs but schistosome antigens in their excreta.

A surveillance work in Assam, Chattisgarh, Madhya Pradesh revealed about 70 % rural population were either showing lesions of cercarial dermatitis or had its history with four passing schistosome antigen in their urine. As cercarial dermatitis is the first stage of human schistosomiasis ,further studies are necessary to assess its full public health impact.

The magnitude is more sever in our domestic animals but here again it depends on rain fall, temperature ,geography,  species , breed, age of animal and husbandry practices ,followed in the places.

Very young animals generally do not suffer because of stall feeding practice while old animals  do not excrete eggs in sufficient number due to thickening of intestinal wall. Cattle is main reservoir host for S.indicum and S.spindale while swine is main reservoir for S.incognitum. Nasal schistosomiasis appears more widely prevalent in India than hitherto considered. This assumption got support by finding Jabalpur like nasal schistosomiasis at other places also where the infection exists symptomless in buffaloes while local cattle appear resistant to the entity.

Schistosomiasis is prevalent in all the states of the country ,affecting mainly ruminants .The infection is not causing only production losses but also outbreaks and heavy mortality ,especially in sheep , but the disturbing fact is that the causative agent is not identified as schistosomes due to faulty diagnostic methods and ailment is wrongly attributed to PPR or alike viral infections. The space is limited for speaking ; all my thoughts and discussions on the topic has been documented in my book “Schistosomes and schistosomiasis in South Asia (ISBN 978-81-322-05388)” which you may follow on the website < www.Springer.com>

10. What are your suggestions and advice to young scientists pursuing their career in Parasitology ?

While doing your Master’s degree , please do not confine only on your thesis problem but imbibe a holistic view of the subject by studying all the aspects of Parasitology. Get mastery at least of the Parasitology text book which is being taught – learn all the important techniques of Parasitology and do not limit only to those related to your thesis work.

When you are doing your doctorate program , critically analyze the research papers , particularly of your research problem , and find out the lacunae in designing their research program. Read critically review articles and advances of Parasitology and see why the author is reaching to particular conclusion and what may be the other possibilities.

While you are starting your research career, restrict yourself only to one topic and devote your whole life to it only as life is very short while problems are fathomless. Be a voracious reader and read more and more about the Parasitologists (e.g. www.drscdutt.com )  and how they worked , may read “After fifty years of research (of Dr SC Dutt)” on my blog www.indianschistosomiasis.blogspot.com .

If you have joined research as a career , please do remember that sky is the limit and this is the field where knowledge is worshiped and you may be remembered years after, for your work , which is not possible in other profession. Do not forget that human civilization has evolved only on the basis of knowledge or research.  

AFTER FIFTY YEARS OF RESEARCH-of Dr S C Dutt

                                         DR MC AGRAWAL 

                FORMER Prof and Head, ICAR  EMERITUS SCIENTIST,
                                   Department of Parasitology

                             

                                          

         

I have read a couplet in recent past, which describes futility of life in following words

bina libas aaye the es  jahan mai, Bas ek kafan kee khatir etna  safar karna pada

(We entered in this world without clothes and traveled  a long journey only for a coffin)

This may be true for most of us who pass their life with no cause but certainly it is not true for persons like late Prof SC Dutt who devoted his whole life for scientific cause. The best testimony  of this is to check ,in present time, the relevance of his research work that was  carried out about fifty years back and his passing away in August,1980. There are two ways to assess, posthumously, the  scientific contributions of a scientist, - first, whether his research work is still cited in research papers and second if further research have supported or nullified his theories or observations; on both accounts he is a winner. I wish to extend the argument with some scientific achievements of Dr Dutt.

The nematode Filariids are known to utilize a mosquito or other blood sucking arthropod as its intermediate host. The filariids, belonging to the family Stephanofilariidae are prevalent in USA, Canada, and South East Asia including India and were first identified in 1933 as an agent for causing dermatitis- mainly in bovines. In India ,Hump-sore is a common skin disease of north-eastern cattle and its etiological agent ,Stephanofilaria assamensis , was identified and described ,first time, by Dr PG Pande  ,IVRI ,Izatnagar in 1936.Nevertheless , life cycle of any Stephanofilaria species remained obscured, though scientists were suspecting various blood sucking arthropods acting as intermediate host for this filariid. To the surprise of all, Dr SC Dutt discovered in 1963 its intermediate host being a Musca species- so far never suspected as an intermediate host for any filariid worm. Scientists were skeptical to this discovery and reluctant to accept the findings; as per general norms, the intermediate host for a filariid must be a blood sucker and Musca does not possess mouthparts enabling the fly to suck blood of the host –rather it is having lapping type mouth parts suitable to lap food material. Dr Dutt incriminated Musca conducens and put a satisfactory explanation for the fly acting as intermediate host. First the filariid is present not beneath the skin but in the skin and its microfilariae are not found in peripheral blood but remains in the skin. The fly has an enlarged chitinized mentum with a pre-stomal tooth and interdental armature (quite different from lapping type mouth parts of Musca domestica, the common house fly) with which it is able to scratch and tear the skin to feed on the serous blood mixed fluid which also contains microfilariae (infective stage for fly) thereby enabling the fly to play its vector role; blood is found an essential prerequisite for oviposition of these flies. This finding was confirmed subsequently by transmission experiments of other workers. Later, in 1970, Dr Dutt incriminated Musca planiceps as the vector for another species of the filariid i.e. Stephanofilaria zaheeri, the causative agent of ear-sore in buffaloes. Even after lapse of so many years of this unique discovery, no worker disputed the finding of M.conducens as intermediate host for S.assamensis or M.planiceps for S.zaheeri nor came out with the results showing any other insect as main intermediate host for the filariid.

The schistosomes or blood-flukes or Bilharzia have been the main field of research for Dr Dutt and he has made many new discoveries on this parasite. In the beginning of his career itself, he made an important discovery that contradicted the than existing hypothesis. As is well known, unlike to other trematodes, the schistosomes are unisexual where male and females are separate individuals, each developing from a single cercaria. While working on life cycle of the blood flukes, scientists found that the snails, the intermediate host where a single miracidium is developing into many cercariae, are regulating sex of the blood flukes by allowing development only of a particular miracidium. In 1930 and onwards, the scientists were working on life cycle of Schistosoma spindale and trying to develop the fluke in experimental animals. However, the animals developed only male S.spindale ; Fairley and associates used good number of guinea pigs  to develop S.spindale but neither its eggs nor females could be observed in any guinea pig prompting Fairley to hypothesize that there are some ‘host factors’ which are preventing development of female S.spindale. This led to  great interest in this discovery and may be visualized by the fact that the prestigious scientific magazine “Lancet” commanded this work in its editorial.

In late fifties, Dr SC Dutt meticulously planned his experiment to check this hypothesis by infecting 24 guinea pigs with different number of S.spindale cercariae (8,000 to 50,000/animal) and sacrificing the animals between 33-153 days post exposure. He provided conclusive evidence of developing females with production of eggs and pseudo-tubercles in the guinea pigs thereby negating the existing hypothesis.  His observations were correct was further proved when in 1990, Dr Anjana Mishra, in her Ph. D. research program  infected albino mouse, albino rats, rabbits and guinea pigs with different doses of S.spindale cercariae and killed them at different time intervals. Interestingly, in these comparative studies, guinea pig emerged as most suitable host for development of S.spindale with highest percentage of fluke development and presence of hundred percent viable eggs, at a time. Therefore, claim of Dr Dutt that guinea pig is developing both sexes has further been strengthened by later research work.

I will like to attract attention on another important problem in late 1960. The etiological agent for nasal granuloma was discovered by Dr Rao MAN in 1933 being a new schistosome species i.e. S.nasale. Though the blood fluke exists  both in cattle and buffalo, it is causing lesions only in cattle while buffalo is maintaining the parasite without any lesions. This led to the possibility of existing two strains or subspecies – one in cattle causing lesions and other in buffaloes without any lesions. Therefore, Dr Dutt decided to solve this problem and conducted cross-transmission experiments in 1968 where cattle were infected with S.nasale of buffalo origin and vice versa. By his experiments, Dr Dutt proved non-existence of two sub-species or strains and its only host species which is responsible for this difference. Subsequent workers confirmed experimentally this finding paving the way to investigate host factors responsible for these differences. The present knowledge also supports the hypothesis of Dr Dutt but with a difference i.e. there appears different geographical strains of S.nasale which is behaving differently – there is one strain in Tamilnadu for which sheep and goats are also susceptible, another strain in Maharashtra where goat is resistant, yet another strain in Jabalpur for which local cattle (but not cross bred cattle) are resistant. All these speculations have been made on epidemiological grounds and biological and biochemical confirmations are still awaited.

There are many other land mark contributions of Dr SC Dutt to the biological sciences and it’s difficult to narrate all of them,here. However, I may mention few of them briefly. Till late fifties, very little was known about Schistosoma indicum though the blood fluke was in lime light because of its resemblance  with Schistosoma haematobium which was found existing in Gimvi village of Ratnagiri district by Gadgil and Shah in 1952. Dr Dutt thoroughly investigated the parasite in association with Dr HD Srivastava including its morphology, life cycle, host susceptibilities that culminated in to publication of an ICAR technical bulletin (34) on Schistosoma indicum. Dr Dutt discovered a new blood fluke (Orientobilharzia dattai) where male was containing many testes ; first the parasite was put ,by them, in the genus Ornithobilharzia but subsequently they created a new genus Orientobilharzia making O.dattai, its type species. The argument put forward was that while Ornithobilharzia contains both avian and mammalian blood flukes, Orientobilharzia possesses exclusively mammalian schistosomes. It may be clarified that the name dattai in the new blood fluke species does not represent Dr SC Dutt  but it was christened in the name of Dr SCA Datta who was the then Director of IVRI, Izatnagar. Interestingly, this new species, unlike to its sister species Orientobilharzia bomfordi ( created by Dr RE Montgomery in 1906 in honor of Dr Bomford but its existence is disputed) , is accepted as a  valid species and occurring in many parts of India. Ironically, there is no further discovery of new schistosome species in India since O.dattai in 1955 and  Dr Dutt’s work remained last taxonomic work for Indian schistosomes though there is dire need of solving many taxonomic problems related to Indian schistosomes.   Another land mark contribution of Dr SC Dutt is about determining intermediate hosts for schistosome species. Prior to his studies, both Indoplanorbis exustus and Lymnaea luteola were incriminated intermediate hosts for S.nasale, S.spindale and S.indicum . By his analytical work , he proved that it is only I.exustus which is intermediate host for all these three Schistosomes exhibiting most restricted host specificity at intermediate level which is in contrast to their final host range. The claim of Dr Dutt still holds true and has been accepted by all scientific fraternity without any exception .

Certainly, this is not a small achievement that even after fifty years there is no one who disputed his findings- further research only supported his observations. A serious thought in this direction should to be given to analyze the reasons responsible for such high quality of research work from late Dr Dutt as it will be  important for our young or emerging scientists . I have witnessed his research persuasions (1970-1974) in the department of Parasitology as his post graduate as well as a Senior Research Assistant  and I have seen this eminent scientist sitting on a steel stool making microscopic studies for hours together which is difficult to follow by most of us. Secondly, he had no hurry to publish his observations , rather he continued to verify his observations by different angles and submitted his research papers only after being satisfied with his observations.

  

Need of National institute of Parasitology

While delivering Dr SC Parija oration award lecture in the 6^th national conference of Indian Academy of Tropical Parasitology ( TROPACON-2012 ) on 13^th Oct,2012 at Shri Auribindo Medical College and post graduate institute , Indore , I , Dr MC Agrawal, advocated the need of opening a national institute of Parasitology in India . Below is a more detailed write up for the proposed  National institute of Parasitology (NIP) .

Name of the institute is proposed to be National Institute of Parasitology and not national institute of parasitic diseases as the former encompasses all aspects of the parasites while latter reflects a narrow  aim of the institute –to deal parasitic diseases. Ironically, there are all sorts of institutes in India like National institute of immunology, national institute of nutrition , national institute of communicable diseases ,national institute of malaria ,national institute of tuberculosis (UNDER ICMR) or national  research centers for equine, camel, goat, pigs, mithun (UNDER ICAR) but  there is no national institute of Parasitology though it’s a must for a tropical country like India. This is because tropical climate of India allow all sorts of parasites to propagate which are responsible for important parasitic diseases in man and his animals including wild animals and fishes. There are many parasitic diseases like malaria, trypanosomiasis, leishmaniasis, toxoplasmosis, amoebiasis, coccidiosis, theileriosis, babesiosis, fascioliasis, schistosomiasis, amphistomiasis, cysticercosis, hydatitosis, haemonchosis, gastrointestinal nematodiasis, filariasis, paragonimiasis and emerging diseases  like cryptosporidiosis, trichinellosis etc which are affecting our animals and human beings; there are important vectors like mosquito, sand fly, ticks, mites which are responsible for transmission of many important diseases (parasites ,virus, bacteria ) and also causing damage to their host in form of allergies and blood loss.

In spite of wide spread prevalence of these and other parasitic diseases throughout Indian continent, there is no National institute of Parasitology that may deal the subject in a holistic way to control the damage and economic losses by these infections. Our negligence on this important issue becomes more pronounced by the fact that other Asian countries like China and Japan etc have national institutes on parasitic diseases which are dealing the subject more efficiently . Even many European countries like Britain, Denmark etc where many of above parasitic diseases are absent due to temperate climate are paying more attention than that of India. These countries are having institutes which are providing specialized training in Parasitology (MSc, Ph.D) to all those who are holding basic degree in life sciences, veterinary or medical sciences and also having international collaborative research projects with endemic countries to deal the parasitic diseases. In India, in contrast, there is no  academic university  of pure science including, BHU, AMU,JNU, which is providing any degree in Parasitology (they are providing degrees in life sciences, zoology, botany, biotechnology). Likewise no Indian medical institute, including AIIMS, New Delhi , JIPMER, Pondicherry, SGPI Lucknow , is imparting MSc or MD or Ph.D in Parasitology  ;here , the subject is studied under department of Microbiology. The only exception is the PGI of Chandigarh which has a separate department of Parasitology  but do not confer MSc in Parasitology though provides Ph.D in Parasitology . Therefore , it is only Veterinary colleges which are having separate department of Parasitology and imparting MVSc and Ph.D  in Parasitology. Here, admissions are given only to those holding BVSc degree and the subject deals with parasites causing infection to the animals only; again  there is less attention on basic aspects of parasites.

Therefore, there is an urgent need of a National Institute of Parasitology that may deal the subject in more holistic way  encompassing all three important faculties- pure science, veterinary and medical and will be a nodal agency to deal parasitic problems of the country. A short outline of the institute may be as given below : 

Name : National Institute of Parasitology

It should be an autonomous body with powers of conferring degrees in Parasitology which should be recognized by all government and private organizations. Its mandate will include dealing all parasitic diseases of Indian continent and having collaboration with national and international organizations for solving parasitic problems.

Faculty

·         Principal Scientist ; Senior Scientist, Junior Scientist  having basic qualifications from all three faculties – pure science, veterinary , medical.

·         There should be provision of taking scientists on deputation from different institutes for short durations.

·         International Parasitologists should be encouraged to join the faculty for a short duration for specific purposes.

·         Even the retired Parasitologists should be taken as Consultants/Advisors for specific projects/topics

Degrees

·         The institute will impart degrees in MSc  in Parasitology and Ph.D. in Helminthology/Protozoology / Entomology .

·         The eligibility for admission will be BVSc &AH/MBBS/ BSc (Hons) Biology or MSc zoology/life science for MSc and Master’s degree in Parasitology for Ph.D.. Admissions should be through an All India entrance examination system.

·         Some seats should also be reserved for international  students .

·         The duration of MSc will be for two/three years and for Ph.D. , three/four years .

·         Both the degrees will include course work as well as a research problem resulting in submission of a thesis. External examination system will be followed for examining the students in their course work as well as for thesis approval .  At least two research papers must be accepted/published in peer reviewed journals prior awarding the degree.

·         The students should be encouraged to take collaborative research projects with other national and international organizations for their thesis problems.

·         The degrees of the institute will make eligible its students to be recruited in all veterinary, medical colleges as well as in the departments of life sciences ;zoology of academic universities .

Parasitic Problems

·         The institute will act as a nodal agency to deal the parasitic problems of the country and will frame rules and regulations to deal them more accurately. As there is a separate National institute of Malaria, the proposed institute will exclude dealing Malaria from its domain , but may join Malaria institute where its effect on other parasitic diseases is to be ascertained.

·         The institute will collaborate with other institutes, including international institutes for solving parasitic problems ,affecting the nation or future problems which may affect the country.

Subjects of study :

·         Traditionally , the subject of Parasitology is divided in three main subjects- Helminthology, Protozoology and Entomology. The study incorporates  Morphology of parasite, its life cycle, diagnosis or key for identifying the parasite, treatment and control.

·         Now the teaching of the subject has changed ,to  identifying the parasite, epidemiology, parasitological and immunological diagnosis , chemotherapy and control measures including biological control.

·         New fields of research have emerged which will need attention . These are identifying strains, hybrids of parasites, molecular studies of the parasites which include PCR studies, isoenzymic studies, biochemical, hormonal changes in the host beside anatomical pathology, clinical Parasitology , phylogenetics and paleo-parasitology, application of remote sensing system in studying epidemiology, molecular epidemiology , nutritional Parasitology, economic losses, monoclonal antibodies, recombinant technology, vaccinology, malacology , parasite genom ,  drug resistance, hyper-parasitism ,molecular diagnosis and other emerging areas of studies.

Finances :

·         The funds will be provided by the Government of India for running the institute. It may be at proportion basis from Ministry of Health (ICMR) and Ministry of Agriculture (ICAR) OR a single ministry may be given responsibility.

·         The institute will also try to fund its projects from international organizations like WHO and FAO

Obviously above is the basic idea for the National Institute of Parasitology and may be fine tuned further by taking suggestions from other organizations/Parasitologists . The only aim of this write up is to emphasize the need for such an  institute in India where parasitic problems of the country may be solved ,incorporating all the present and future knowledge of the subject. 

(Part of this write up was published by "THE PARA-SIGHT-2" volume 2 issue 1 of IAAVP ) 

WHY SCHISTOSOMIASIS SHOULD STILL BE STUDIED IN INDIAN CONTINENT

M. C . AGRAWAL

Former Emeritus Scientist , and ICAR National Fellow

Department of Parasitology , College of Veterinary Science and AH

Jabalpur 482001 MP

(E.mail mcagrawal@yahoo.com : www.indianschistosomiasis.blogspot.com )

I feel privileged that the selection committee of Indian Academy of Tropical Parasitology considered me suitable for Dr SC Parija oration award for the year 2012 and express my gratitude for this kind gesture. I have selected the topic schistosomiasis for my discussion not only because I have worked over the subject throughout my life but also as I consider that it has the capacity to cover all the fields of life sciences where all three faculties zoology, veterinary and medical may work together to solve the problem and is a good model for teaching Parasitology. Another reason for selecting this topic is as I am witnessing standstill of research work on schistosomiasis in India after my retirement and termination of ICAR NATP scheme on Diagnosis of parasitic diseases where Jabalpur and Hisar centers were working on schistosomiasis. With the help of my colleagues, I have compiled almost all the research on schistosomes and schistosomiasis carried out in the country in last 100 years in a book form (Agrawal, 2012) but this must be considered not a stop but a comma , to start the research with a new perspective ,new vigor and with new design to handle the problem . In this lecture, I will touch a few topics where research is needed in schistosomiasis with regards to India or South Asia.

ZOOLOGY FACULTY : This is a pure science discipline where Parasitology is supposed to deal basic problems of a parasite like taxonomy , evolution , life cycle etc.

Species identification : The first species of Schistosoma namely Schistosoma haematobium was identified in 1852 in an Egyptian boy and other species ,S.mansoni , was recognized as a separate species ,due to different egg morphology in 1903. India was not far behind in this research as in the year 1886, Bomford could record presence of schistosomes in two bullocks in Calcutta (Agrawal 2012) and in 1906 , Montgomery was able to describe three schistosome species (S.indicum,S.spindale S.bomfordi ) ,simultaneously , from India. Further, Chandler (1926) described a new species ,S.incognitum, from West Bengal on the grounds of recovering morphologically different eggs from human excreta while Rao (1933) created a new species, S.nasalis, on the basis of different location (nasal cavity ) causing nasal schistosomiasis in bovines. It’s a different story that both the new Indian species (S.incognitum and S.nasalis) did not get reference in the monograph written by Bhalerao in the year 1935 who accepted existence of S.haematobium, S.indicum,S.spindale,S.bomfordi ,S.japonicum and S.bovis in India.

In the year 1952, Gadgil and Shah recorded urinary schistosomiasis in village Gimvi of Ratnagiri district, Maharashtra and as per host and location specification of the parasite, they identified it as S.haematobium though later work revealed that Ferrissia tenuis and not Bulinus snails were acting its intermediate host extending the possibility of considering it a new Schistosoma species. Since then no new species under genus Schistosoma has been discovered from India although Orientobilharzia dattai (Ornithobilharzia dattai ) is the last mammalian blood fluke that was discovered by Dutt and Srivastava in 1952  . Does it mean that we have ---------------------------------------------------------------------------------------------------

Present address : ¾,Datt Arcade Phase Three, South Civil Lines, Jabalpur 482001 MP

identified all the Schistosoma species existing in the country ? Contrarily,  the number of Schistosoma species is continuing to swell day by day internationally and at present there are 22 valid Schistosoma species without any new contribution from this country (Agrawal,2012) .

It is not that there is no probability of existing of any new schistosome species in India but the fact is that no serious attention is paid on the topic by Indian taxonomists. Mammalian schistosome cercariae have been recovered from Lymnaea aurricularia whose adults are still not confirmed. We have reported S.bovis like eggs in the albino mice ,experimentally infected with cercariae recovered from Indoplanorbis exustus with male flukes of disputed morphology (Agrawal 2012) . There is also a report of finding oval shaped, spined schistosome eggs from two human stools from Andhra Pradesh whose species have yet not be identified (Bidinger and Crompton, 1989 ) . Rajkhowa et al ( 2005 ) claimed recovering S.bovis eggs from the faecal samples of Mithun from NorthEastern states ; as S.bovis is not existing in this part of geography , it is a case of miss-identity and the eggs might be belonging either to S.spindale or to a new blood fluke species.

Thus, it appears that new mammalian schistosome species are existing in the country and awaiting their discovery. However, any future research should not be carried out exclusively on traditional morphological ground but some more new parameters should be incorporated in such studies. These may be electron microscopy to study minute morphological details, some biochemical parameters like iso-enzymic studies and biological studies to know the differences in patent period ,both in intermediate and final hosts and differences in host susceptibilities . Inclusion of more than one parameter in any future study is essential to confirm any new schistosome species as the differences between known and new species may be overlapping and may not remain beyond controversy if only morphological data are depended on . It may not be out of place to mention that since long S.japonicum was considered a single Schistosoma species , than a species complex and now it has ramifications with identification of separate new species like S.mekongi, S.malayalensis, S.sinensium when detailed studies were carried out on S.japonicum species complex.

Life –Cycle : In fact , we know details only of five schistosome species that are existing in India i.e. S.indicum,S.spindale,S.nasale,S.incognitum and Orientobilharzia dattai. We do not know details of other blood flukes which are discovered from the country , long back. These are Orientobilharzia bomfordi (syn S.bomfordi), Orientobilharzia harinasutai, Bivitellobilharzia nairi, and S.haematobium (?) from Gimvi village . Even intermediate host of none of these blood flukes are known from India though Lymnaea gibsoni is the intermediate host for O.harinasutai in Thailand and Bulinus species are the snails for S.haematobium in other countries . As O.bomfordi and B.nairi have been discovered from India itself with no report of their occurrence in any other country , we are completely ignorant which snail species is acting as intermediate host for these two schistosomes .

Among these blood flukes, B.nairi is exclusively occurring in the elephants and on evolution consideration , blood flukes of proboscides i.e. elephants, should be considered as oldest blood flukes of the mammals . It is amazing how this blood fluke is maintaining itself in nature for thousand years , surviving exclusively in elephant and whose intermediate host is yet elusive from catch suggesting that not many snails are being infected with the fluke at a given period of time. The case of Gimvi fluke is again interesting which confirms its existence in the country but with affirmation of absence of Bulinus species from the continent. For this reason, Ferrissia tenuis was suggested its intermediate host by providing experimental proof but un- answering some questions. An important question is that this snail species is existing in many other parts of the country than why other regions have not been surveyed for positivity of the snail with this blood fluke species or why snails of other regions were considered resistant to this or any other schistosome species(Agrawal 2012).

When we are not aware about the snail species of these blood flukes , there is no question of knowing other details which are important to understand epidemiology of the infection. Once the intermediate host is known for these blood fluke species, further studies are to be undertaken to know susceptible age of snails , mortality of infected snail, pre-incubation period , shedding period of the cercariae , infectivity of cercariae to final host species ,biology of the snail species, etc. In fact, a detailed study on the life cycle of the blood fluke will be possible once intermediate host is identified for these blood flukes.

MEDICAL FACULTY : It appears that ICMR has never involved itself seriously in tackling the problem of schistosomiasis in India. In the start of twentieth century , when first and second world wars caused influx of troops from endemic countries , this was the Indian Army which requested Indian scientists to investigate the chances of spread of schistosomiasis in the country because of returning of soldiers from endemic countries . When the scientists confirmed no chance of spread of the infection in man because of absence of desired snail species in India, a complacent view was created considering man safe from this menace in India . But not much later, Gadgil and Shah (1952) confirmed an endemic focus of urinary schistosomiasis in Gimvi village of Maharashtra state where almost one third population showed signs of the infection. It was also confirmed that a local snail species is responsible for maintaining the infection in the village ; neither there was any restriction on migration of human population to other parts of the country nor the snail species (Ferrissia tenuis ), suspected for existence of the schistosome , are existing exclusively in and around Gimvi village . Even then, it’s surprising why Indian scientists considered the incidence as an isolated one with no probability of its spreading or occurring in any other part of the country. If it’s true that S.haematobium (?) was confined only in Gimvi village , it will be an unique example in the history where a new schistosome species could exist only in a very small geographical area otherwise schistosomes are notorious in engulfing large part of the geography .

Even in post independence period , reports appeared where human stools were shown positive for schistosome eggs . We may mention here at least two reports –one of Dhanda (1956) from Northern India and other from Andhra Pradesh. The former report considered, eggs belonging to S.haematobium, perhaps a miss identity while second report , prepared with the help of British expert on schistosomes (Crompton), abstained itself in naming the schistosome species . Further, it’s difficult to ignore some reports of pre-independent India where positive men have never left the country suggesting acquiring the infection from Indian soil itself ((Baugh,1978). All these evidences strongly support existence of foci of human schistosomiasis in the country which are awaiting investigations from our scientists.

Perhaps a more direct proof of human suffering has come in recent years when scientists (Narain et al 2000, Agrawal et al 2000 a,2000b Rao et al 2007) reported wide prevalence of cercarial dermatitis in rural population. This malady is prevalent in almost all the villages in Madhya Pradesh, Chhattisgarh, Assam , where surveys were made, and whose population is dependent on local ponds for their domestic needs . It is also widely prevalent in rural professionals like fisherman, boatman ,water chest nut growers or laborers etc. No further studies have been made in this direction. Whether , cercarial dermatitis is first or last stage of schistosomiasis in these cases is not known i.e. if schistosomulae are killed in skin itself or are able to migrate to lung , liver and mesentery of human beings with possibility of their survival for long time in certain hosts specially immuno -deficient human beings. It may be emphasized that cercarial dermatitis is caused not only by avian schistosome cercariae but mammalian schistosome cercariae are also responsible for causing it. Therefore ,there is all the possibility of survival of schistosomes in human body in many such cases as some cases showed presence of humoral antibody by CHR test (Agrawal et al 2006) and a single step kit, imported from Netherland, revealed schistosome antigens in the urine of five human beings having history of cercarial dermatitis raising question if active schistosomiasis is existing in India (Agrawal et al 2007) . Again , avian schistosome cercariae may not always be least pathogenic as cercariae of Trichobilharzia rhahnati are not only responsible for cercarial dermatitis but possess the character of migrating to nervous system , including brain, leading to nervous symptoms; we are completely ignorant about this phenomenon in India. Therefore, it is not wise to ignore the cases of cercarial dermatitis in rural population and a more concrete plan should be formulated to investigate these cases employing all modern techniques.

VETERINARY FACULTY: As a maximum number of mammalian schistosome species, reported from any single country, are occurring in India , infecting domestic as well as wild animals, it is obvious that ICAR has more responsibility of solving the problem and should pay more attention on the infection ,particularly when it is causing considerable mortality and animal production losses not because of a single host species but many domestic animal species. However, ICAR has not paid desired attention to contain the infection and I am not aware if any research scheme of ICAR on schistosomiasis is under operation at present . I may mention a few problems in present day discussion .

Our domestic animals (sheep ,goat ,cattle ,buffalo ,dog) are susceptible to more than one schistosome species , but it is our domestic pig which is susceptible only to S.incognitum and no other schistosome species has been recovered from it from India. The pig during its scavenging visits all local ponds, sewage areas , stagnant water sources hence its natural of its exposure to all types of schistosome cercariae , prevalent in that area . But the animal has an innate resistance to all schistosome species except that of S.incognitum . Study of this phenomenon may lead to identification of some host factors responsible for making pig resistant to all schistosome species except that of one species.

Another interesting case relates to Camel which appears quite resistant to schistosome infections as there appears no report of schistosomiasis (with one exception) in this host species. Whether it is because of different grazing habit of the camel which keeps it away from schistosomiasis or it is resistant to all species of the schistosomes will be worth investigating subject.

There are reports of outbreaks of schistosomiasis in sheep ( Lodha et al 1981, Chandra et al 2003 ) and cattle ( Kulkarni et al 1954 ,Singh et al 2000) from different parts of the country. These outbreaks have revealed a high morbidity as well as a high mortality leading to heavy economic losses to the country. Yet no detailed studies have been undertaken to understand these out breaks and how they can be controlled.

A perturbing fact is about failure of diagnosing schistosomiasis in our domestic animals even when intensity of the infection is causing production losses and mortality (Agrawal,1999) .This is further substantiated by a research paper of Chandra et al (2003) who examined some serum samples of sheep , dispatched from Karnataka and Andhra Pradesh ,suspecting death due to Rinder pest . All the samples were negative for this or any other viral or bacterial infection and further scrutiny of the cases led to diagnosis of schistosomiasis in all the sheep flocks of these two states but exhibiting symptoms simulating to Rinder pest. Even in an old outbreak of schistosomiasis in cattle due to S.spindale, the symptoms were resembling those of Rinder pest ( Kulkarni et al 1954) suggesting how diagnosis is being confused ; it further warns that schistosomiasis should be taken seriously by our veterinarians and all attention should be paid to develop efficient diagnostic methods for schistosomiasis in our domestic animals considering the low egg output by the Indian schistosomes.

Nasal schistosomiasis or snoring disease is affecting cattle in whole of the country but nothing substantive has been done to control this ailment . Neither any effective molluscicide to control snail population nor any vaccine has been tried even on a pilot basis. The only methodology ,followed in the field, is treating individual cases with Anthiomaline or Praziquantel which suppresses the symptoms temporarily with their recurrence after 3-4 months of time.

However, none of these drugs and also the recently tried Triclabendazole (Singh and Agrawal 2005) are able to kill any Indian schistosome species to a significant level. It must be emphasized that both Anthiomaline and triclabendazole are being used in bovines extensively in Indian continent ; the former for treating nasal schistosomiasis and latter for fascioliasis . As both the drugs have some killing effect on schistosome species, the extensive field use of these two drugs is leading slow exclusion of susceptible schistosome population from the nature and what will left after some time will be a resistant population of schistosomes to any of these drugs. To this can be added the misery that even the most effective schistosomicide Praziquantel , is not effective in killing any Indian schistosome species to the significant level ,even in present day scenario . Thus , this is a future warning of the things which may come in our way , if immediate attention is not paid on this topic.

NATIONAL INSTITUTE OF PARASITOLOGY : What may be the way to solve above and many other problems ,related to parasitic diseases of man and animals in the Indian continent. In my opinion, there is an urgent need to start an autonomous central government sponsored national institute of Parasitology . It will be important to have persons from all three faculties (zoology, medical and veterinary ) in its staff with mandate of dealing the problems of parasitic diseases of man and animals and asking deputation of imminent scientists from all where to solve the problem of parasitosis . It may sound odd that India does not have any national institute to deal with parasitic diseases although confronted with so many parasitic diseases whereas some European countries, like Britain , Denmark etc have international institutes of Parasitology though these countries do not face big problems on parasitic diseases.

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