Bull. Org. mond. Sante | 1954, 11, 679-723 Bull. Wld Hlth Org. MALARIA CONTROL IN SOUTH MALABAR, MADRAS STATE L. MARA, M.D. Senior Adviser and Team-leader, WHO Malaria-Control Demonstration Team, Suleimaniya, Iraq formerly, Senior Adviser and Team-leader, WHO Malaria-Control Demonstration Team, South Malabar Manuscript received in January 1954 SYNOPSIS The author describes the activities and achievements of a two- year malaria-control demonstration-organized by WHO, UNICEF, the Indian Government, and the Government of Madras State- in South Malabar. Widespread insecticidal work, using a dosage of 200 mg of DDT per square foot (2.2 g per m2), protected 52,500 people in 1950, and 115,500 in 1951, at a cost of about Rs 0/13/0 (US$0.16) per capita. The final results showed a considerable decrease in the size of the endemic areas; in the spleen- and parasite-rates of children; and in the number of malaria cases detected by the team or treated in local hospitals and dispensaries. During December 1949 a malaria-control project, undertaken jointly by WHO, the United Nations Children's Fund (UNICEF), the Govern- ment of India, and the Government of Madras State, started operations in the malarious areas among the foothills and tracts of Ernad and Walavanad taluks in South Malabar. During 1951 the operational area was extended to include almost all the malarious parts of Ernad and Walavanad as well as the northernmost part of Palghat taluk (see map 1 a). The staff of the international team provided by WHO consisted of a senior adviser and team-leader and a public-health nurse. This team was matched by a parallel Indian team consisting of a malariologist, a senior entomologist, two lady health-visitors, a sanitary engineer (provided by the Madras Government for a period of two months during the first year), and the following junior technical and administrative staff: 6 entomological assistants; 7 health inspectors; 2 lady health-visitors; 3 midwives; 22 field assistants; 6 laboratory assistants; 1 laboratory technician; 1 office a In this map, villages with numbers 1-4 and 24-37, and village no. 30, belong to Ernad taluk; villages with numbers 5-16 and village no. 38 belong to Walavanad taluk; and villages with numbers 17-23 belong to Palghat taluk. 337 - 679 12 680 L. MARA assistant; 1 upper division clerk; 5 lower division clerks; 1 draftsman; 1mechanic; 5 drivers; 3 cleaners; 2 chowdikars; 23 peons; 6 laboratory boys; and 3 ayahs. MAP 1. AREA UNDER JURISDICTION OF MALARIA-CONTROL DEMONSTRATION TEAM ______------ Taluk boundary Rivers and streams Vi Village boundary ^A ^ ^A Foothills Metalled road with milestones . .. Water edge Unmetalled road with milestones Equipment and supplies were received from UNICEF, which also- together with the Madras Government--provided transport facilities. The Madras Government, in addition, participated by supplying the team with some additional equipment and assuming responsibility for replacing the expendable supplies when they were used up. Since even the most fundamental information about malaria epidemiology was lacking in the areas where the teams were to operate, MALARIA CONTROL IN SOUTH MALABAR 681 a great deal of research had to be carried out in addition to the scheduled control work. It is calculated that two-fifths of the work was devoted to the study of the area during the first year, and one-third during the second year, when the project was extended to new areas. During the first operational year, the cost of the project to the Madras Government represented a total expenditure of Rs 1,16,592/11/-, and during the second year, Rs 1,69,755/5/1. The WHO team withdrew from the operational area at the beginning of December 1951, after handing over all activities and transferring all respon- sibility for their continuation to the parallel Indian team. Area of Operations (First and Second Operational Years) Description of the area (see map 1) Malabar, which with South Kanara District represents the westernmost part of Madras State, is divided administratively into two distinct parts North Malabar and South Malabar. Organizationally, Malabar District consists of several taluks (adminis- trative divisions) within which the villages (" amsoms " in the local idiom) are the first step of the administrative framework of the country. Only in a few cases is the village itself divided, for administrative purposes, into sub-villages (" desams "). The term " village " in South Malabar does not indicate merely a rural agglomeration more or less comparable to a hamlet, but refers to the paddy-fields, rivers, hills, jungle, forests, and all surveyed or unsurveyed land within an administrative boundary. The size of these villages is extremely variable, some covering only a few square miles, some as many as 40 square miles (104 kM2) and some even as many as 300 square miles (777 kM2), as in the case of Attappadi. The inhabitants of the villages are scattered throughout the entire area and show little tendency to congregate. The edges of the paddy-fields and the network of roads are the only natural gathering-places, and it is here that one finds the highest population density. The distribution of the houses in a village is always very irregular, especially when the geographical area is large and the population relatively small. Malaria in South Malabar is found chiefly along the narrow foothills strip running north and south which follows approximately the very winding contour line of 250 feet (76 m). Beyond the limits of that strip, malaria, as a general rule, does not exist. To the east is the western slope of the Western Ghats, a territory consisting entirely of dense jungle and solid virgin forest which is, in fact, completely uninhabited. To the west of the foothills line malaria decreases very rapidly as soon as the plain begins, and this can be considered a healthy area. However, some minor spots of autochthonous malaria can be found (exception confirming the rule) even within the 682 L. MARA healthy areas of the plain and in limited areas on the western slope of the Ghats. House-to-house visiting in the course of the preliminary surveys in the different sectors showed that of all the cases of sickness found, 27.8 % were due to malaria. The location of the malarious tracts of South Malabar in which the WHO team operated during its two-year stay is approximately between 10045'N. and 11032'N. and 75055'E. and 76050'E. The total surface of this area is more than 800 square miles (2,075 kM2), of which about 500 square miles (1,295 km2) are completely uninhabited and about which very little is known. During 1950 the demonstration was carried out in the malarious villages of Nilambur and all the others numbered from 2 to 16 in the list on map 1. This area under the jurisdiction of the team located along the foothills of the Western Ghats measured about 140 square miles (360 km2). During 1951 the area was expanded by the inclusion of an additional -175 square miles (455 kM2), incorporating the malarious tracts of 15 more villages in Ernad taluk (24-37 and 39), the village of Attappadi (38) in Walavanad taluk, and the malarious portion of seven other villages (17-23) in the taluk of Palghat. Thus, the total inhabited malarious areas brought under the jurisdiction of the team amounted to approximately 315 square miles (815 km2), representing five-sixths of all the malarious areas of South Malabar. This extension of the activities of the team to new sectors, how- ever, was followed by the loss of the physiographical uniformity throughout the whole scheme because of the differences existing either between the new sectors and those of the first year or between the new sectors themselves. Whereas during 1950 it was possible to claim considerable physiographical uniformity throughout the entire foothills area (which lies at a constant altitude of between 200 and 250 feet (61-76 m)), during the 1951 programme this uniformity disappeared with the inclusion in the scheme of areas such as Attappadi on the eastern slopes of the Western Ghats at an altitude of between 1,500 and 3,000 feet (457-914 m), and the isolated malarious spot around Arimbra and Uragam Melmuri which lies within the healthy area of the Ernad sub-coastal plain. The total extent of cultivated land within the project area at the end of 1949 was 50,547 acres (20,456 ha), which was increased to 52,631 acres (21,299 ha) by the end of 1950. To synthesize in a clear way the description of the physiographical features of the areas under the jurisdiction of the team, together with their most relevant aspects, it is necessary to divide the entire project into three well-defined sectors and to describe the ecology of each. These sectors are: (a) the sector of the highlands, within the Attappadi valley; (b) the foothills line, which is the very narrow strip separating the Malabar plain from the Ghat range; and (c) the isolated area of Arimbra-Uragam Melmuri. MALARIA CONTROL IN SOUTH MALABAR 683 (a) Attappadi (38). This valley, which is very wide and deep, is the beginning of the course of the Bhavani river. It consists of a single village, the largest in the entire project area within Walavanad taluk, and lies on the opposite side of the watershed of the Western Ghats with its open side towards Coimbatore District. Its surface is about 360 square miles (930 kM2), of which roughly only one-third is inhabited. The entire area is very wild, and the general economy of the valley is among the most undeveloped in the entire State of Madras.