Note: This article is taken from Immunohaematology Bulletin with
the kind permission of Dr. Kate.
S. L. Kate
Ten percent of the total population of the State of Maharashtra belongs to tribal population groups. These groups remain isolated, living in remote forest and hilly areas far from civilization. Majority of them have poor health status, peculiar health needs and a wide prevalence of red blood cell genetic disorders that complicates their health problems further. Moreover, the inadequate health infrastructure in tribal areas to deal with such complicated health problems is a matter of grave concern.
As per the recent information available from the Govt. sources, Maharashtra State ranks second in population and area wise third in the country. As per the 1991 census, the total population of the State is 80 million and this is 9.33 percent of India's population. The total tribal population in the State is 7.4 million that accounts to about 9.3 percent of the total population of the State.
There are three mountain ranges in the State known as Sahyadri, Satpuda and Gondwan ranges. In total, there are 47 scheduled tribal population groups in the State and majority of them are inhabitants of these geographically difficult terrain. [Note: "Scheduled tribal populations" is a term applied by the British colonialists to groups in India who by and large successfully resisted their control in the 19th century. "Clans" might be a more appropriate term. -KRB]Out of these 47 groups, 17 are major tribal groups. In the Sahyadri ranges there are the Mahadeo Koli, Katkari, Warli, Malhar Koli and Kokana groups. Among Satpuda ranges, Bhil, Pawara, Korku and Tadvi are the major groups. The Madia, Gond, Pardhan, Halbi Otkar, and Andha are found in the Gondwan range.
These tribal groups differ from each other in various aspects. They
differ in the language they speak, in their cultural pattern and socio-economic
categories. As the majority of these tribals living in the remote forest
areas remain isolated, untouched by civilization, they are largely unaffected
by the developmental processes going on in the rest of the State. Therefore,
these groups remain backward, particularly in health, education and socio-economic
aspects. We are working in the field of tribal health for the last several
years and the health problems of the tribal population in the State can
be summarized as follows:
Table 1: Health Status Indicators in Tribes
|Infant mortality rate||
|Crude death rate||
|Maternal mortality rate||
|Delivery by TBA||
Among the genetic problems, we have conducted and in-depth study on sickle cell disorders. Best examples of genetic polymorphism clearly connected with disease are sickle cell anemia, thalassemia and glucose 6-phosphate dehydrogenase deficiency. These are single gene defects of the blood, totally confined to red blood cells. Sickle cell anaemia and thalassemia are the major public health problems in our country (1,2,4,6,9,10). Thalassemia is prevalent amongst all population groups irrespective of caste, religion and creed. However, sickle cell disorder is mostly confined to socio-economically backward groups, like scheduled castes (SC), scheduled tribes (ST) and nomadic tribes (NT).
Sickle Cell Disorder
This is a hereditary blood disorder due to defective hemoglobin structure. Hemoglobin is a tetramer consisting of two pairs of non-identical globin and polypeptide chains, each chain being associated with one heme group. The heme group is an iron containing pigment responsible for oxygen transport in red blood cells. There are four polypeptide chains (alpha, beta, gamma and delta) in the globin portion. HbA consists of 2 alpha and 2 beta chains; HbF consists of 2 alpha and 2 gamma chains and HbA2 consists of 2 alpha and 2 delta chains. The alpha chains consist of 141 amino acids with specific sequences, while beta, gamma and delta chains consist of 146 amino acids. The sequences of amino acids in the alpha, beta, gamma and delta chains are different from each other and very specific for that chain. Sickle cell hemoglobin sickling and hence the mutant hemoglobin is called sickle cell hemoglobin (HbS).
The Genetics of Sickle Cell Hemoglobin
It is well documented that the gene for sickle cell hemoglobin is located on the short arm of chromosome 11 and has an autosomal recessive inheritance. Hence, it can manifest in two forms viz. heterozygous (carrier) and homozygous (sufferer). When two carriers marry, the chance of having a homozygous child is 25% every pregnancy.
Diagnosis of sickle cell carriers and sufferers is possible by careful
clinical examination of the patient supported by laboratory investigations.
For developing countries like India, simple, rapid and inexpensive yet
reliable laboratory tests are necessary, particularly, when screening has
to be carried out on large populations located in geographically difficult
areas. Such techniques have been developed in our Dept. that are suitable
for field work and require minimum amount of blood (only a few drops).
The results are available within half an hour and the test is very cost
effective. The tests include:
Population genetic survey data from our Dept. indicates that the prevalence of sickle cell disorder in the overall population of Maharashtra is less than 0.1% while it is very high amongst the tribal population groups from Nandurbar and Gadchiroli districts of the State. The same tribal population groups residing in the neighboring states of Gujarat, Madhya Pradesh and Andhra Pradesh have a similar prevalence. Our epidemiological data suggests:
|Sr. No||Tribal Group||District||Sickle Cell
|4||Madia, Gond||Gadchiroli, Yeotmal||20.8|
|13||Katkari||Pune, Raigad, Ratnagiri||5.90|
|16||Mahadeo Koli||Pune, Nasik||0.81|
|17||Thakur||Pune, Thane, Raigad, Ahmednagar||0.00|
Sickle Cell Anemia
All the clinical complications recorded in the literature are found among patients from tribal population groups. The clinical, molecular and genetic aspects of sickle cell disease have been reviewed (7). Although some generalization about the genotype-phenotype correlation may be made, sickle cell patients sharing identical genotypes exhibit considerable heterogeneity in clinical symptoms. Some of the common symptoms seen in patients suffering from sickle cell anaemia include:
* Intermittent Jaundice
* Severe joint pains
* Recurrent infections
These symptoms usually appear between the ages of four and five and severity increases with age. Most of the patients do not require blood transfusion. Careful history, presence of the above mentioned symptoms and caste constitute basis for diagnosis of sickle cell anemia.
No genetic disease could be simpler than sickle cell anaemia. It is a simple disease but there is no cure. In the absence of any cure, majority of the sickle cell patients have a miserable and short life span. Instances of sudden death have also been reported in such cases. The available treatment strategies can be broadly divided into five categories: anti-sickling agents, vasoactive drugs, enhancing fetal hemoglobin production, bone marrow transplantation and gene therapy. Unfortunately neither the diagnostic nor the above mentioned treatment facilities are available in tribal areas and all these are beyond their reach. Although the tribal health problem is grave, the Health Department is unable to provide them with any health care for several reasons. Teachers and medical students who have sufficient knowledge about the subject are most unwilling to work in tribal areas. Ultimately, the patients approach traditional healers known as "Bhagat" in whom they have complete faith and confidence. Since there is no specific treatment available for the disease, the only alternative is prevention. Therefore, we can undertake such preventative measures like health education and genetic counseling. Studies carried out in Cyprus, Greece and the UK for similar types of diseases using such preventative strategies have shown promising results (5). A preliminary report on the prevention of sickle cell disorder in India is cited (3,8).
Sickle Cell Disorder and the State of Maharashtra
Studies carried out by our centre and other scientists from different institutions indicate that the overall prevalence of sickle cell disorder in different tribal populations is 10% for carrier state and 0.5% for the sufferer. The total tribal population from the State of Maharashtra as per the recent Govt. record is 90 lakhs at the end of the 20th century [Note: lakh equals 100,000. -KRB]. Based on this number, the expected carriers of sickle cell would be 9 lakhs and expected number of sickle cell homozygotes would be 45,000. The prevalence is very high among the Bhil and Pawara tribal groups from the Nandurbar District and the Madia, Pardhan, Otkar and Gond from the Gadchiroli District. It is estimated that there are more than 10,000 sickle cell patients in the Nandurbar District itself. The Gadchiroli District is expected to have more than 5,000. Taking into consideration the problem of sickle cell disorder, the Indian Council of Medical Research (ICMR) launched a preventative program on a trial basis among high risk tribal populations in the State of Maharashtra. We established two community control programme centres, one in the Nandurbar District and the other in the Gadchiroli District. The major activities of the Centres are:
|Total villages selected||8||6|
|Total population screened||4116||2912 (including SC/ST)|
|Total carriers detected||824||525|
|Total sufferers detected||44||37|
|Prevalence of sickle cell disorder||21%||20%|
|Total population of the district||1,00,000 only ST||47,000 SC/ST|
Even though prevalence is very high in the district, parents, patients and private medical practitioners have very limited information about the disease. We had detailed discussions with the parents of sickle homozygous children. About 50% of the parents showed keen interest in the subject. When provided with this information, they were surprised to know that they could have avoided such sufferings of their children. With this background, we organized several discussions, meetings and arranged demonstrations in villages on sickle cell disease.
Our survey showed that in every village there are at least one or two patients suffering from sickle cell disease. People of the village were aware of the suffering of these patients and had a deep sense of sympathy and compassion for them. We explained to them about the hereditary nature of sickle cell disease and that no curative treatment is available although it can be prevented. This had a good impact on the general population and was the major beginning for creating community awareness for the counselling programme.
We distributed identity cards giving the sickle cell status to every individual and explained the concept of marriage counselling to prevent the disease. They also readily accepted the concept of family planning to prevent the birth of further affected children. Some such parents have now become counsellors for sickle cell anemia in their villages.
We had also organized several lectures for school and college students living in the high risk areas, explaining to them the principles of genetics, mode of inheritance, high prevalence of sickle cell disease in tribal areas, giving them detailed information on sickle cell disease including control and treatment. The students were tested for their sickle cell status and we gave them counselling cards explaining to them that marriage counselling is the only solution for the disease. All male students collected the cards but about 20% of the female students did not turn up even to collect the cards, in fear that in case they were carriers or sufferers of sickle cell, it may become known to others. This was despite our promise to keep their sickle cell status confidential.
Simultaneously, we organized lectures on sickle cell disorder for the local Govt. and private medical practitioners, including paramedical workers, explaining to them about the prevalence, diagnostic methods, possible treatment, complications and prevention aspects of the disease. Although we carried out these activities for a limited period, our experience suggests that we have definitely created awareness among people about sickle cell disorders in the areas where we have established community control programmes. However, it is necessary to continue with such activities and with our experience we are hopeful that with devotion from medical scientists from multi-disciplinary fields, people will accept marriage-counselling programmes.