4. MALARIA PROBLEM AS EVIDENT FROM THE RESULTS OF …shodhganga.inflibnet.ac.in/bitstream/10603/915/8/08_chapter 4.pdf · 4.2.2. Comparison of malaria situation between four physiographic

4. MALARIA PROBLEM AS EVIDENT FROM THE RESULTS OF ANALYSES OF AVAILABLE DATA

Page. .61

4. ANALYSES OF A V A I M L E WTA ON M I A .

The history of malaria and the gravity of the situation in the

district in the first half of this century have been reviewed in the

prtlvious chapter. This chapter deals with the analyses of data

available for Koraput district. A ccinparison h:s also been made with

the situation in the two neighbouring districts of Andhra Pradesh.

4.1. MTA SOURCE AND MEINIDS OF AVALYSES:

For the present analyses, data were collected from published [data

on India: Kondrashin and Rashid, 1987: Orissa state and districts:

Anonpus, 1987c ) and unpublished sources. The unpublished sources

include the following:

i). PtC and district malaria authorities n f Koraput district,

Orissa.

ii). M and district ~mlaria authorities of Vishakhapatnam and East

Godavari districts, Andhra Pradesh.

iii]. State malaria authorities and regional director at^ of health,

Ht~ub@neswar, Ori ssa.

A computer database was created and data were analyzed for

malarimtric indices, such as annual parasite incidence per 1,000

Page. .62

population [API), slide positivity rate [proportion positivity of blood

smear slides collected expressed as percentage: SPR), annual blood

examination rate (proport ion of population covered by blood smear

examination annually expressed as percentage: ABWI and proportion

positivity for g. falciparm to total positives expressed as percentage

(Pf % ) . Fqhasis was given to the spatial and temporal distribution of

malaria. For studying seasonality, monthly incidence of parasitaemia

per 1,000 population was calculated. Age and gender specific analyses

could not be carried out due to non-availability of suitable data. No

data on spleen examination was available from the above sources.

Regression analysis was used to study the relationship between API and

ABER. Since only two parasite specles (11, falciparm and P, viva) were

recorded in the above data, the figures, for falciparum only are shown

in the tables in this chapter. The period between 1976 and 1988 was

covered depending on the availability of data from individual sources.

4.2. RESULTS:

4.2.1. Contribution of Koraput to malaria cases in Urissa and India:

The total number of srnear proven lr~alaria cases and scme

malarianetric indices for India, Orissa and Koraput for the period

1981-86 are shown in Table: 3. While the national API ranged between

2.40 to 4 .11 in different years (Kondrashin and Rashid, 19871, the

figures for Koraput were about 6 to 7 times higher (API ranging between

'Table: 3

Malaria situation in Koraput compared with that in Orissa state and India.

- ---

Number of malaria cases

INDIA 2701141 2182302 2018605 2184446 1864380 1765631 ORISSA 303471 296478 252152 283927 246703 316138 KORAPUT 65528 61225 50169 57542 43395 39447

Annual parasite incidence per 1000 population

INDIA 4.11 3.22 2.93 3.08 2.57 2.40 OR1 SSA 11.55 11.08 9.26 10.00 10.00 11.29 KORAPUT 26.37 24.12 19.35 21.72 16.04 14.27

Nunher of P. fnlciparun cases

INDIA 589591 551057 600964 655454 545005 621235 CUISSA 238832 239761 200234 226188 195800 259011 KORAPUT 56346 54804 45190 52064 38653 38525

Percentage of P.falciparum to total cases

INDIA 21.8J 25.25 29.77 iU., i1 2Y.UU 35.18 CUI SSA 78.70 80.87 79.41 80.00 79.00 80.03 KORAPUT 85.99 89.51 90.07 90.48 89.07 97.66

(Source: Kondrashin and Rashid, 1987: State and district malaria authorities).

14.3 to 26.4). The API in the district was about one and half to twice

that of the figures for the whole of Grissa state. While P. falciparm accounted for 22-358 of cases in India, i t accounted for about 80% of

cases in Orissa and between 86-98% of cases in Koraput.

Though Orissa state contributed to about 11-18% of all malaria

cases of India, its contribution to P. falciparm cases was highest and

ranged between 33% and 44%. Koraput district with a population

measuring a fraction of less than 1 percent (0.36%) contributed between

2.23% to 2.81% of all cases and 6.20% to 9.95% of P. falciparun cases

of the nation (Table: 4). The official records indicate that 80 deaths

due to malaria had occurred in this district between 1981 and 1986

[Table: 5).

4.2.2. Comparison of malaria situation between four physiographic

regions in Orissa state:

Orissa has been divided into 4 physiographic regions [Dash 2 g.,

1984), of which Koraput district comes under the eastern ghat zone (for

details, see chapter: 2.1). Comparison of the malaria situation in the

four zones (Table: 6) showed that highest API was recorded in the

northern plateau followed by the eastern ghat region. The proportion

[ % ) of 1. falciparlul~ cases howcvcr was the highest In Ihc latter. While

the national figures have shown a declining trend, all the zones in

Grissa recorded higher API in 1986 ccmpared to 1985. When analysis

Page. .65

Table: 4

Contribution of Orissa state to national. Koraput district to state and national malaria situation.

YEAR

1 9 8 1 1982 1983 1984 1985 1986

ORISSA COMPARED TO INDlA

% of all cases 11.23 1 3 . 5 9 12 .49 1 3 . 0 0 13.23 1 7 . 9 1 % off. falciparm cases 40 .51 43 .51 33.32 34 .51 35.93 40.73

KORAPUT m m m TO ORISSA

% of all cases 21.59 20 .65 1 9 . 9 0 20.27 17 .59 12 .48 % of P. falciparum cases 23.59 22.86 22.57 23.02 19.74 15.23

KORAPUT COMPARED TO INDIA

% of all cases 2 .43 2 .81 2.49 2.63 2.33 2.23 % , O f P . falciparwncases 9.56 9.95 7.52 7.94 7.09 G.20

(Source: coopliled from data available from Kondrashin and Rashid. 1987: State and district malaria authorities).

Table: 5

Malaria si tuatir~n in Ko~.~lpul district.

No. +ve - P. falciparwn Nu. of Year ESC ABM for SPH API malaria

malaria No. +ve 8 deaths

I3SC : Blood smears collected and examined ABM: Annual blood examination rate ( 8 1 SPR : Slide positivity rate ( 8 1 API : Annual parasite incidence per1.000 population. N"i: No1 Abailable (Source: District nnlaria authorities)

Table: 6

Comparison of malarianetric indices between four physiographic zones of Orissa state.

YEAR

ZONE INDEX 1984 1985 1986 84-866

COASTAL API 5 .00 3.90 4.75 4.55 PLAINS pf rb 48.38 46.80 60.73 51.97

W m N AP I 22.33 16.27 21.84 20.15 GHATS p f % 87.53 84.91 83.32 85.25

NORTHEEN API 20.00 22.24 27.17 23.14 PLATCAU Pf % 76.64 79.21 83.26 79.70

API: Annual lJarasi te lncitlence per 1,000 [~opulatiorl P f % : P. falciparum as proportion of all malaria cases ( 8 )

* Average of 1984 to 1986.

(SOURCE: State malaria authorities).

was done for individual districts (Table: 71, Phulbani, adjacent to

Koraput in the sane zone recorded the highest API, while Koraput ranked

fourth.

When the data for Koraput district [Table: 5) was examined, both

API and SPR showed a declining trend over tht: ys~lrs. c. lalciparwn was the predominant parasite in the locality and its prevalence showed an

increasing trend until 1986, when about 98% of the cases reported were

due to this species. The prevalence of this parasite, however,

decreased marginally in the last two years (1987-88).

4 . 2 . 3 . Comparison of malaria situation between the physiographic zones

within the district:

'he malarimtric indices for the four zones in the district are

shown in Table: 8. Malkangiri zone was the worst affected recording

highest API throughout the period. Jeypore zone recorded the lowest API

each year. The year to year variations between 1981 and 1988 in the

four zones are shown in Figure: 7. ?he declining trend in API (Figure:

7C] and SPR [Figure: 7B) was qualitatively similar in all zones,

excluding in Koraput zone where the API has clearly increased during

1987-88 canpared to the previous years. The pattern of API and SPR

mimicked the pattern of ABER in general [Figure: 7A) . A significant

correlation was observed between ABER and API (r = 0.78; P (0.0011

irrespective of the zones. The prevalence of 11. lalciparum over the

Page. .69

Table: 7

Ccmparison of malaria situation between different districts of Orissa state (Average of 1984 to 1986) .

ZONE DISTRICT API Pf %

COASTAL G A N J W 12.75 78.61 PLAINS PURI 3.24 54.32

CU?TPCK 0.84 44.35 &4LASORE 1 . 3 6 30.60

CENTRAL S-PUR 8.13 82.27 TABLE LAND BOLANGIR 7.01 75.00

WEM(ANAL 12.03 49.91

W T E R N KDRAPUT 17.87 88.90 GHAT HiU1HANI 34.17 87.05

KALAHANDI 8.47 79.81

NORTHERN M4YUREltiAN.l 16.08 68.48 PLATE4U KEDNJHAR 26.58 82.88

SUNDERGARH 26.76 07.75

API: Annual parasite incidence per 1.000 population Pf%: Proportion of p. falciparum cases to total

malaria cases ( % I

(Source: State malaria authorities)

Table: 8

Carparison of Malaria situation in different physiographic zones of Koraput district.

Koraput Jeypore Rayagada Malkangiri (46001 ) * (989956) (523135) (290805)

Year API Pf% API Pf% APT Pf% API Pf%

API: Annual parasite incidence per 1000 population Pf%: P. falci arum as proportion of all rnalarla cases (81 * ~i~iires in Earentheses show the population of 1981: NMEP census

Page. .71

- 20

E 15 RAYAGADA MALKANGIRI KORAPUT JEYPORE

30 - E 20 UALKANGIRI KORAPUT

a 10 a 0 JEYPORE RAYAGMA

60

40 MALKANGIRI KORAPUT RAYAGADA JEY PORE

100

90 KORAPUT

" 80 RAYAGWA HALKANGIRI 2 70 JEY PORE

FIGURE: 7. Comparison of year to year variations in Annual Blood Examination Rate (ABER), Slide Positivity Rate (SPR). Annual Parasite Incidence/l,OOO Population (API) and proportion of P. falciparun out of total parasite carriers (PI 2 ) in four different zones of Koraput. (order of zones arranged differently for clarity)

years did not show any uniform trend (Figure: 70). While proportion of

P, falciparun cases to total malaria cases was highest in Koraput zone - betwen 1981 and 1984, i t was highest in Jeypore zone in 1985 and ih

Malkangiri zone between 1986 and 1988 (Table: 8) .

4.2.4. Comparison of malaria situation between primary health

centres within the district:

The district has 42 Primary Health Centres (PHCs). All the PHCs

have recorded malaria cases throughout the period between 1981 and

1988. The average annual malariometric indices for the period 1981 to

88 are shown in Tat~le: I). The average API rangetl between 2.52 in

Kosomaguda PHC (in Jeypore zone) to 50.74 in Chandrapur PHC [in

Rayagada zone). API as high and 102 and 162 were recorded in Chandrapur

(in 1982) and in Mathalput RIC (in 1987) respectively. To have an idea

of the spatial distrikution 01 malaria, the PHCs were classified into 4

groups based on the average API (Map: 4 ) . It was observed that areas of

high, moderate and low API were distributed throughout the four zones.

b s t areas recording API of over 30 appeared to lie on roughly a

straight line f r m southern tip of the district towards middle of

northeastern side near Bism Cuttack, which actually corresponds to the

chain of hills in eastern ghat ranges. There were 6 PHCs n'ith . P I less

than or equal to 10 , 1 8 R1Cs recorded API between 1 0 and 20, 8 PHCs

between 20 and 30 and 1 0 PHCs above 30 (the lower limits are not

included). The year to year variation in API in 42 R1Cs do not show any

Page. .73 Table: 9

Caparison of malaria situation between the different R1Cs of Koraput district (Average between 1981-88).

- -

RIC W POPULATION ABER API SPR ~ f %

Chandrapur Narayanapatna Khairput Kalimla Hamanaguda Malkangiri Lamp taput Laksbipur Kolnara Mathalput Bori gmna Boipariguda Jaganathpur Korukunda Kundura Gudari Kotpad Podia Dabugon Kalyan Singhpur Bandhugaon Kashipur Sarmosigam Jharigaon Ha tbharandi Chandahandi Kudunu lugma Pottangi B.Cut tack Nandahandi Muniguda Kundul i Rabanguda Puj ari guda Jemadipetho Dasamnthpur Mathili Packnapur Tentulikhunti Papadahandi Nandapur Kosagmda

ABER: Annual blood examination rate ( % ) SPR : Slide positivity rate ( P i ) : API : Annual parasite incidence per 1000 population. Pf% : Proportion of P. falciparum cases to total positives ( % I

(SOURCFi: District malaria authorities, Koraputl

Page. . 7 4

HAP: 9 Malaria situation in Koraput district:

Classification of Primary Health Centres (PHCs) according to average Annual Parasite Incidence (API) per 1,000 population (1981-1988).

--

Lower limits of API not included.

uniform pattern in any zone (Figure: 8; data for some randomly chosen

IllCs U ~ O SIICJWII 111 1110 Ilgu~u). AS in 1110 cilso ul zullcs, lliu N'l ul~d

ABER in the W C s showed a significant correlation (r = 0.63; P<O.001).

lhis is also evident from the similarity in patterns of the two

parmters in different RiCs (Figure: 8 ) .

4 . 2 . 5 . Comparison of malaria situation between sections within WCs of

the district:

For operational purposes the 42 PHC areas are divided into 502

sections. For the implementation of control programne, sect ions are

considered as the smallest unit of population. The population in each

section is to be covered by one surveillance worker in the fortnightly

fever surveys. Though the average population for each section would

workout l o 4,015, Lllo ;rc:t11,11 [ ~ c ~ l ~ ~ ~ l a t ior~ i l l Lhi!sn st:ct Ions varicd

between 1,197 and 26,638, Data for the sections were available only

for the 3 year period (1983-85). lhe data revealed that the API varied

widely between these sections. 'he lowest API of 0.1 was recorded both

in Ramgiri section (Boipariguda PHC) in 1983 and in Maligam

(Rabanaguda PHC) in 1985. Highest API of 314.3 was recorded in

Narayanpatna-A section (Narayanpatna MIC] in 1984. Ihe wide variations

in the malaria situation is also evident from the data for the sections

of 2 PHC areas presented in Table: 10.

Page. . 7 6

80 80

40 API 40

ABER 0 0

Y U

100 APl

50 ABER

0

81 82 83 84 85 86 87 88 [Year)

8 API

4 ABER

o ; , , , 81 82 83 84 d5 06 $7 QB

(Year)

PICURE: 8. patterns of year to year variation in APl and ABER in 6 randomly chosen primar, Health Centre areas in KoraPut district.

Page. .77

Table: 10

Canparison of annual parasite incidence ( A P I ) in different sections of two PHC areas in Koraput district.

SECTION YFA? SECTION E A R

1983 1984 1985 AVERAGE 1983 1984 1985 AVET(AGE

- - - -

A P I . Annual Paras~te lncldence per 1,OII~l pupulatlon

(SOURCE: District malaria authorities)

Page. .78

4.2.6. Caparison between villages:

There are 5,683 villages and on an average, each section covers

about 10 to 11 villages. To study the village to village variations in

API, the data from 22 villages from 7 sections of Borigm R1C were

analyzed [since data were available only for these villages). It was

observed that the average API [between 1984 and 1988) varied widely

between 24 and 245/1,000 population in these villages (Table: 11)

4.2.7. Seasonal pattern of malaria:

Data on soasoliai pallcrn of ni,iiaria in Ihc ri15trlr.l WCIS iivoilahl~:

for a period of 6 years (1981-86). Malaria cases were recorded

throughout the year and the average monthly lncldence of malaria per

1,000 population (1981-86) peaked during rainy season between July and

Scpterrber (Figure. ' 3 ) . Tl~c int:~rir:nc.c In i~ year [lc:r~riri shr~wod a

declining trend over the years (Figure: 10). But this declining trend

was also acc~npanied by corresponding decline ~n year to year AQER

(Table: 5 1 .

Canparison of seasonal variations in incidence of malaria between

the four zones was done by calculating the nmber of malaria

cases/1,000 ppulation for each month [average of ii years data

1981-1986; Figure: 11). Two peaks of parasite incidence were observed

in Koraput and Jeypore zones, one in July - August and the other in

Page. .79

Table: 11

Comparison of Annual parasite incidence (APII between 22 villages in Lhrigcrma tW, Jeypora zone.

API in the year Village Section Popul-

nmber ation 1984 1985 1986 1!)87 1988 - /"''r"6t!

Bsinghpur 431 1389 28.8 29.5 32.4 33.8 33.8 31.68 Benagam 423 925 22.7 22.7 33.5 22.7 24.9 25.30 mnasur 431 691 50.7 243.1 62.2 42.0 47 .8 89.15 Bi j apur 425 202 267.3 203.0 1 6 3 . 4 158.4 148.5 188.12 Bondhuguda 425 656 36.6 45.7 44.2 39.6 30.5 39.33 Deulaguda 424 146 205.5 287.7 356.2 191.8 184 .9 245.21 Dul laguda 424 555 39.6 64.9 68 .5 39.6 41.4 50.81 Jhilimili 424 415 50.6 50.6 53 .0 67.5 69.9 58.31 Kadaliguda 423 271 81.2 73 .8 77.5 62.7 55.4 70.11 Kanagam 426 614 34.2 48.9 42.3 70.0 65 .1 52.12 Kenduguda 424 305 75.4 154 .1 150 .8 65.6 49.2 99.02 Keraput 431 429 86.2 79 .3 83.9 53.6 60.6 72.73 Kunduraguda 426 619 24.2 33.9 35.5 30.7 35.5 31.99 Mndaguda 431 1061 33.0 30.2 16 .0 54.7 37.7 34.31 Nuaguda 431 595 45.4 47.1 47.1 H.4 20 .2 33.61 P . B o r i g m 424 952 34.7 36.8 33.6 13 .7 11.6 26.05 Podapadar 431 1500 24.0 30 .7 33.3 27.3 25.3 28.13 Porli 428 761 32.9 31.5 31 .5 1H.4 15.8 26.02 Ranaspur 432 799 86.4 42.6 53.8 33.8 30.0 49.31 Sargiguda 423 750 34.7 36.0 38.7 20.0 20.0 29.87 Seamalaguda 431 1139 29.9 28.1 29.9 19 .3 4 24.41 jontoshpur 423 529 58.6 104.0 62.4 51.0 51.0 65 .41

API: Annual parasite incidence per 1 , 0 0 0 population

(SOURCE: FHC authorities. Borigunnal.

Page. .80

J P M A I J J A S O N D (Months)

PICURE: 9. Seasonal change8 in average (1981-86) parasite (1) and P. falciparum (2 ) incidence in Koraput diatrict in re- - - lation to the rainfall pattern.

Page. .81

PICURE: 10. Year to year variations in parasite incidence in Koraput district in relation to the rainfall pattern.

J P M A l J J A S O N D (Month)

J P M A M J J A S O N D (Month)

PIGURE: 11. Seasonal variations in average (1981-861 parasite (11 and P. falciparum (2) incidence in relation to rainfall pattern - - in 4 zonea of Koraput.

Noventwr. However, the peeks were less conspicuous in Jeypore zone. ?he

seasonal fluctuations in the Rayagada zone were not well marked,

though the highest incidence was in July - August. In Malkangiri zone, there was only one peak during Septenber - Decerrber in the post monsoon season. The incidence was low in the month of May which gradually

increased to reach a peak in Septmer, following which i t declined.

4.2.8. Malaria situation in the two adjoining districts of Andhra

Pradesh:

Vishakhapatnam and East Godavari districts of Andhra Pradesh, lie

to southeast and south of Koraput district respectively (Map: 1).

Physiographically both the districts are divided into plain areas and

agency tracts. The hills on south eastern parts of Koraput are

continuous with those in north western parts of these districts in the

agency tracts. In fact, all these were part of the 'Agency area' of

erstwhile Madras Presidency. The population and its distribution in

these areas are similar. Tribals constitute 94% and 68% of population

of agency areas in Vishakhapatnam and East Godavari districts

respectively. The density of population is also low I68 and 34 per

sq.lan, in Vishakhapatnam and East Godavari respectively) .

?he malaria situation in these two districts are shown in Tables:

12 and 13. The data for Vishakhapatnam city and the steel plant area

are not included in the district figures, since these areas have a

Page. .84

Table: 12

Malaria situation in Vishakhapatnam district. Andhra Pradesh (excluding the Steel Plant Township).

No. +ve - P. falciparm Year BSC for ABER SPR API

malaria No. +ve %

BSC : Blood smears collected and examined ABEX: Annual blood examination rate ( % ) SF3 : Slide positivity rate ( % I API : Annual parasite incidence per 1000 population (Source: District malaria authorities)

Page. .85

Table: 13

Malaria situation in East Godavari district, Andhra Pradesh.

No. +ve P. falciparum Year BSC for SPR API

malaria No. +ve %

BSC : Blood smears collected and examined ABER: Annual blood examination rate ( % I SPR : Slide positivity rate ( % ) API : Annual parasite incidence per 1.000 population

(SOURCE: District malaria authorities)

different problem altogether not related to any other part of the

district: in 1985 a total of 5,222 malaria cases were detected in these

areas as against 4,203 cases in rest of the district. 'he data indicate

that these two districts recorded lower API compared to Koraput

[compare Tables: 1 2 6 1 3 with Table: 51 . Approximately 80 and 60 % of

all reported malaria cafiefi wore frim thrl iq:onr:y ;I~O;IH 1 1 1

Vishakhapatnam and East Godavari districts respectively. However, the

data from the agency areas indicate that API in Vishakhapatnam declined

from 29.3 in 1976 to 19.3 in 1981 and to 5.0 in 1986 (year to year

details for agency areas of Vishakhapatnam were not ava~lablel, and in

East Godavari f r m 30.1 in 1981 to 12 .6 in 1985 (Table: 1 4 ) . The

decline was marked in the f o m r when compared to the latter. Though

the PHCs bordering Koraput recorded higher malaria compared to other

parts of agency area in both districts, a declining trend over the

years was observed here also. In Dmuriguda PHC in Arraku area of

Vishakhapatnam district the API had declined from 42.5 in 1976 to 5.7

in 1986 (Table: 1 5 ) . In Maredmalli PHC in East Godavari, i t had

declined from 188.3 in 1977 to 16 .9 in 1986 [Table: 16). The sections

bordering Koraput in hnriguda PHC in Vishakhapatnam recorded high API

in late 70s, following which there was a decline (Table: 1 7 ) . In 1986,

the Donkarai and Mangapadu sections in East Godavari district bordering

Koraput , recorded API of 39.6 and 22.8 respectively [ABER of 52.75% and

34.72% respectively). The ABER in agency areas of both the districts

was much higher ccmpared to Koraput (Tables: 14 to 171. Relationship

between API and ABER was also studied. 'he data for the district as a

Page. .87

Table: 14

Malaria situation in the agency areas of East Codavari district, Andhra Pradesh.

No. +ve P. falciparm Year BSC for ABER SPR API

malaria No. +ve %

BSC : Blood smears collected and examined ABER: Annual blood examination rate ( % ) SPR : Slide positivity rate ( % I API : Annual parasite incidence per 1000 population

Page. .88

Table: 15

Malaria situation in Dunriguda R1C (Arakku subunit), Vishakhapatnam district. Andhra Pradesh.

No. +ve P. falciparun Year BSC for ABW SPR API

malaria No. +ve %

BSC : Blood smears collected and examined ABER: Annual blood examination rate (8) SPR : Slide positivity rate (8) API : Annual parasite incidence per 1000 population

(SOURCE: District malaria authorities)

Page. .89

Table: 16

Malaria situation in Maredunalli PHC. East Godavari district. Andhra Pradesh.

No. rvo c. falciparun Year BSC for ABER SPR API

malaria No. +ve %

BSC : Blood smears collected and examined ABER: Annual blood examination rate 1 % ) SPR : Slide positivity rate ( $ 1 API : Annual parasite incidence per 1.000 populatirln

(SOURCE: District malaria authorities)

* Includes collections under IGvR scheme

Page. .90

Table: 17

Annual parasite incidence (API) in different sections of Vishakha- patnam district, Andhra Pradesh, bordering Koraput district.

API: Annual parasite incidence per 1,000 population.

whole showad that there was a significant correlation between the two

parmters [Vishakhapatnam: r = 0.70, P = 0.04, Table: 12: East

Godavari: r = 0.78, P = 0.04, Table: 13). But the data did not show any

correlation between the two parameters in the Agency areas of East

Godavari (r = 0.78, P = 0.06, Table: 14). Dunuriguda R1C (r = 0.50, P =

0.12, Table: 15) and Maredunalli FlK [r = 0.01, P = 0.97, Table: 1 6 ) ,

which are very close to Koraput and where the ABER was high.

Analysis of the data on seasonality of malaria indicated that the

patterns in these two districts were similar to that in Koraput

district: the peak monthly incidence of parasitaemia was between June

and August, during rains (Figures: 12 and 13). However, quantitatively

the levels of parasi taemia were much lower compared to Koraput [conpare

Figures: 12 and 13 with Figures: 9 and 10). For the above comparison,

data from 1977 to 1985 were available for entire Vishakhapatnarn

district, while for East Godavari district data only for 1985 and 1986

that too for Maredunalli PHC alone were available.

4.3. DISCUSSION:

The present analyses indicated that the Koraput district continued

to remain highly malarious. P. falciparm was the predominant parasite

species and its prevalence was high from the early part of the century

(Perry, 1914; Senior White, 1937a; Senior White, 1938; Viswanathan,

1951). P. ~ l a r i a e which was prevalent in the early part of the! century

Page. .92

0.6-

a 3 0 . 5 - a

J F l A M J J A S O N D (Month)

FIGURE: 12. Seasonal changes i n average (1977-85) Paras i t e ( 1 ) P. falciparum ( 2 ) and P. ( 3 ) inc idence i n - - Vishakhapatnam d i e t r i c t .

J P M A M J J A S O N D (Month)

FIGURE: 13. Seasona l changes i n average (1985-861 P a r a s i t e (1 ) . P. falciparum ( 2 ) and P. =x ( 3 ) inc idence i n - - Waredurnalli PHC area of Bast Codavart d t u t r l c l .

Page, ,93

(Perry. 1914) was conspicuous by its absence in these records.

Analysis on spatial distribution indicated that malaria problem

was not homogenous in different parts of the district. Tht?re were

variations between physiographic zones, W s within the zones, sections

within the PHCs and villages within the sections. The seasonality of

malaria also differed betwen the zones. These findings confirm the

fact that malaria is essentially a local problem as emphasized earlier

[Covell, 1949; Downs, 1981). Therefore the feasibility of malaria

control by application of an uniform strategy throughout the district

is debatable. This in turn justifies the ntxd for detailed

epidemiological investigation of the local malaria problem for

replanning control measures IWn, 1974; Kondrashin anrl Rash~d. 1987;

Beales etg. , 1908; Kondrashln and Kalra, 1988a; Kondrashln and Kalra,

1988b: Kondrashin and Kalra, 1989a; Kondrashln and Kal ra, 198Sb;

Rajagopalan, 1989).

Comparison of malaria problem in the two neighbouring districts of

Andhra Pradesh intiicatod that thore has bct?n a cons~dt:rablc: Improverent

in these districts unlike in Koraput. Further, the malaria problem in

these districts is primarily limited to the agency tract and areas

bordering Koraput. The reasons for improverent in the situation in

Andhra Pradesh and persistence of the problem in Koraput have been

dealt in detail elsewhere [chapter: 10 ) .

There were certain difficulties in the assessment of malaria

situation with the available data. Since spleen surveys were not

carried out (as this is not done under present programne: S h a m ,

1984a), classification of areas under degrees of endemicity (Pampana,

1969; Bruce-Chwatt. 1985) was not possible. Age (and sex) specific

anfllyfils cnulri riot 11u rl11m1 111111 1 1 1 nl~rl-ilv~ll l c ~ l l l l l l y 1 1 1 h111 1,111111

infomtion. The usefulness of age specific patterns of prevalence in

understanding the disease epidemiology is well known. While the level

of infant parasitaemia indicates transmission, data on child

parasitaemia is useful for endemicity classification of areas (Pampana,

1969; Bruce-Chwatt, 1985; bblineaux. 1988). Differentlation of

symptmtic and asymptomatic parasite load in the popl~lation was not

possible. This is not only important for deciding the level of imnunity

in the population, but also in designing control strategy (Greenwood,

1987).

Under the present programne. API forms the basis for deciding the

type of control measure (Pattanayak and Roy, 1980; S h a m , 19114a). In

an ideal situation. API and ABER are expected to show a positive linear

relationship initially, but as the malaria control becomes effective,

API should decline even when ABER remains high (hblineawt. 1988). m e

fact that API in Koraput district continued to remain as a function of

ABER, shaved that effective control has not been achieved. In the agency

areas of Andhra Pradesh, on the other hand API continued to be low even

when ABW was high (Compare Tables: 14. 15. lfi with Table: 5 ) . Tne use

of API however, may not be suitable in situations where there are large

nunber of asymptamtic parasite carriers. mere have been several other

limitations in the use of API (WH3, 1964: Najera, 1989) .

No doubt that the present analyses could reveal the tenporal and

spatial variations in the distribution of malaria in the district, the

gravity of the situation may be worse than h a t is apparent. Studies

carried out in other parts of the country had shown that the actual

prevalence of malaria was higher than reported under the national

programne ( S h a m g z.. 1983; Choudhury. 1984). I t is well known that

due to several reasons the estimates of malaria deaths under the

national programne is far f rorn sat isfactory IAnonjm~us, 1985a). A1 1

these necessitated a detailed study of the lrlalarla problem tor

understanding the causes of persistence in the locality.