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EPIDEMIOLOGICAL REVIEW OF

LEPROSY IN THE WESTERN PACIFIC REGION

2007

(t!/~ ~ World Health ~~_!Jorganization ~-----r Western Pacific Region

EPIDEMIOLOGICAL REVIEW OF

LEPROSY IN THE WESTERN PACIFIC REGION

2007

WHO/W PRO LIBRARY MANILA. PIULIPPINES

1 6 JU L 2009

World Health Organization

Regional Office for the Western Pacific

Manila, Philippines

With data available as of December 2005

PREPARED BY

The Stop TB and Leprosy Elimination Unit in the WHO Regional Office for the Western Pacific,

Pieter van Maaren and Sumana Barna, in collaboration with Dr Arturo C. Cunanan, Jr., WHO Consultant

ACKNOWLEDGEMENTS

We would like to thank all national leprosy programme managers and statisticians from all the countries

and areas of the Western Pacific Region for providing appropriate data for this document.

WHO Library Cataloguing in Publication Data

Epidemiological review of leprosy in the WHO Western Pacific Region, 2007.

1. Leprosy- epidemiology. 2. Western Pacific.

ISBN 978 92 9061 315 2 (NLM Classification: WC 335)

© World Health Organization 2007

All rights reserved.

The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted lines on maps represent approximate border lines for which there may not yet be full agreement.

The mention of specific companies or of certain manufacturers' products does not imply that they are endorsed or recommended by the World Health Organization in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters.

The World Health Organization does not warrant that the information contained in this publication is complete and correct and shall not be liable for any damages incurred as a result of its use.

Publications of the World Health Organization can be obtained from Marketing and Dissemination, World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel: +41 22 791 2476; fax: +41 22 791 4857; email: [email protected]). Requests for permission to reproduce WHO publications, in part or in whole, or to translate them - whether for sale or for noncommercial distribution - should be addressed to Publications, at the above address (fax: +41 22 791 4806; email: [email protected]). For WHO Western Pacific Regional Publications, request for permission to reproduce should be addressed to Publications Office, World Health Organization, Regional Office for the Western Pacific, P.O. Box 2932, 1000, Manila, Philippines, Fax. No. (632) 521-1036, email: [email protected].

II

Updated information on leprosy in the Western Pacific Region is available at:

http://www.wpro.who.int

CONTENTS

2

3

4

5

6

7

8

SUMMARY ....... ... .... .. .... .. ..... ..... ..... ... .. ........ ..... .... ....... .... ... ... 1

INTRODUCTION ..... ... ... ... .. ·· ·~·· · ...... ...... .... .......... ......... .... ...... .

ACHIEVEMENTS ·· ·· ·~·· ·· ······ · ···· · ··· · · · ····· · ·· ·· ·· ··· · ·· · · ·· ·· · ··· ·· ·· · · · · ··· ·

EPIDEMIOLOGICAL SITUATION ..... ... .... . .............. ..... ... .... ... .

PROGRAMME ACTIVITIES ............. ... .... ... .. .. ....... ... ... ... .... ... .

ISSUES AND CHALLENGES ... .. ... ..... .. ..... ................. ............ .

FUTURE PRIORITIES AND ACTIVITIES ... ....... ........ ... .... ...... .

RESOURCE REQUIREMENTS .. ..... ..... ... .. ..... .. ... ... ..... ....... ..... .

5

6

7

15

18

20

22

FIGURES AND TABLES

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Table 1

Table 2

Table 3

Table 4

Leprosy prevalence rates and multidrug therapy

in the Western Pacific Region (1988-2005)

Distribution of new cases ofleprosy detected in 2005

New case detection rates per 100 000 population in 2005

Distribution of registered cases and the prevalence rates per 10 000 for eight countries in the Western Pacific Region (2005)

Trend of prevalence and new case detection rates (1991- 2005)

Trend of prevalence rates after elimination in some large countries and areas

Trend of new case detection rates after elimination in some large countries

Trend of prevalence rates after elimination in some small countries and areas

Trend of prevalence rates in two countries that have not yet achieved the elimination target in the Western Pacific Region

Latest notification of leprosy cases and monitoring indicators by countries and areas, 2005

Distribution of countries as to attainment of elimination target in 2005

Proportion of MB, disability grade 2, and children below 15 years among new cases (1994-2005)

Trend of the prevalence and new case detection, Western Pacific Region (1991-2005)

5

8

9

10

13

14

14

14

20

3

7

11

13

iii

ABBREVIATIONS

HEC Health education campaign

KAP Knowledge, attitudes and practices

LEC Leprosy elimination campaign

LEM Leprosy elimination monitoring

MB Multi bacillary

MDT Multidrug therapy

NGO Nongovernmental organization

P!D Prevalence/detection ratio

ROM Rifampicin-Ofloxacin-Minocycline

WHO World Health Organization

iv

SUMMARY

This epidemiological review of Leprosy 2005 in the Western Pacific Region of

WHO is based on information collected from 37 countries and areas ofthe

Region, as well as other sources. A total of 30 countries and areas have sent

annual leprosy data for 2005 (Table 1). The population, prevalent cases, and

new cases reported of the six countries and areas that did not send their data

was 20.8 million, 13 million, and 17 million, respectively.

The estimated population of the Region for the year 2005 was 1.74 billion. Of

the 33 countries and areas that eliminated leprosy as a public health problem

(defined as the prevalence of less than one case per 10 000 population) at

the end of 2004, all33 countries and areas have sustained elimination status

in 2005. Kiribati had lost its elimination status due to the detection of a large

number of new cases, following the launching of a leprosy awareness campaign

and active case detection activities in 2003, but reduced the prevalence rate

by 47% in 2005. Leprosy has continued to be a public health problem in the

Federated States of Micronesia and the Marshall Islands. Yet eight countries

and areas have reported zero prevalence and new case detection.

The registered cases at the end of 2005 were 9460, with a prevalence rate of

0.054 per 10 000 population. The prevalence rate continued to decline by

5.2% compared to that of 2004 and by 87.4% compared to that of 1991

when the Region attained the elimination goal. Ten countries and areas

reported less than 10 registered cases, while only two (China and the

Philippines) had more than 1000 registered cases.

There were 7201 new cases reported in 2005, with a new case detection rate

of 0.413 per 100 000 population. The new case detection rate has increased

by 14% compared to 2004. This increase is artificial and may be attributed to

the intensified case finding and awareness campaign activities in Kiribati,

the Federated State of Micronesia, the Philippines, and the Solomon Islands.

The prevalence/detection (P/D) ratio at 1.3 showed a marginal decrease in

2005. However, in countries and areas such as China, Malaysia, the Republic

of Korea, and Singapore, patients are being managed with multidrug

treatment regimens of longer duration than recommended by WHO.

During the year 2005, health education and leprosy awareness campaigns

and rapid surveys of endemic pockets were completed, in addition to

screenings of selected populations in Kiribati, the Federated States of

Micronesia, the Philippines, and Solomon Islands, resulting in the detection

of significant numbers of new cases.

Epidemiological Review of Leprosy 2007


2

The biregional strategy developed in 2004 to sustain leprosy services

following elimination was introduced in 2005 in Cambodia and VietNam by

organizing national level workshops. A plan of action was developed to further

reduce the disease burden by focusing on high endemic pockets at the sub

national levels and by addressing problems pertaining to physical, social,

and economic rehabilitation of leprosy-affected persons in the coming years.

The regional prevalence rate, which had reached elimination level in 1991,

has declined continuously thereafter. First and second level sub-national

elimination has been achieved in big countries like Cambodia, China, the Lao

People's Democratic Republic, the Philippines ( exceptfor a few provinces and

cities), and VietNam. The new case detection rate-which fluctuated soon

after elimination-has started to decline from 1998levels; however, the rate

of fall of both prevalence and case detection are slowing down since 2004,

with a marginal increase in the case detection rate in 2005. A similar picture is

also emerging in countries and areas such as Cambodia, the Lao People's

Democratic Republic, the Philippines, and Viet Nam after reaching the

elimination target. In China and in the Republic of Korea, elimination was

accomplished prior to 1991; with an initial fall after reaching elimination,

both prevalence and case detection rates have stagnated since 1997. As

such, quality leprosy control activities that are integrated into the general

health services, as outlined in the biregional strategy, would be pursued in

the aim of sustaining elimination and Leprosy services in the coming years to

further reduce the disease burden and prevent resurgence of the disease.


TABLE 1 Latest notification of leprosy· cases and monitoring indicators by countries and areas, 2005

Prevalence New Case Detection

Country

American Samoa (2004)

Australia (2004)

Brunei Darusalaam

Cambodia

China

Cook Islands

Fiji

French Polynesia

Guam

Hong Kong (China)

Japan

Kiribati

Republic of Korea

Lao P.D.R.

Macao (China) (2003)

Malaysia

N. Mariana Is. (2003)

Marshall Islands

Micronesia, F.S.

Mongolia

Nauru

New Caledonia (2003)

New Zealand

Niue

Palau

Papua New Guinea

Philippines

Pitcairn Islands (2004)

Samoa

Singapore

Solomon Islands

Tokelau

Torga

Tuvalu

Vanuatu

VietNam

Wallis and Futuna (2003)

Summary

Population X 1000

65

20155

374

14071

1315 844

18

848

251

170

7041

128085

99

47817

5924

460

25347

81

62

110

2646

14

237

4028

1

aJ

5887

83054

185

4326

478

1

102

10

211

84238

15

1752283

• Proportion of Multibacillary (MB) cases

No.

4

0

1

348

3171

0

5

16

9

32

3

19

4aJ

140

1

7':IJ

!l

37

158

0

0

0

0

0

2

536

lll6

0

5

25

21

0

0

0

2

642

0

9460

Ratex 10 000

0.62

0.00

0.03

0.25

0.02

0.00

0.06

0.62

0.53

0.05

0.0002

1.91

0.09

0.24

0.02

0.30

0.99

5.97

14.30

0.00

0.00

0.00

0.00

0.00

0.99£

0.91

0.37

0.00

0.27

0.06

0.44

0.00

0.00

0.00

0.09

0.08

0.00

0.054

•• Proportion of cases with grade 2 disability among new cases ••• Proportion of children younger than 15 years among new cases

No. Rate-x MB* 100 000 %

3 4.62 6(il.7

5 o.o2 ro 0.27 0.0

429 3.05 70

1658 0.13 89.1

01 0.00 0.0

4 0.47 75

10 3.90 00

6 3.54 100

4 0.06 100

6 0.00 83.3'

34 34.22 32..4

15 0.03 100

143 2.41 762

1 0.22 100

263 1.04 67.3

4 4.95 75

<14 11.01 ro 2&1 235.32 ll

0 0.00 0.0

1 7.33 100

4 1.69 0.0

2 0.05 liJ

0 0.00 0.0

2 10.03 100

381 6.47 54

3130 3.77 84.3

0 0.00 0.0

7 3.78 100

13 0.30 54

25 5.23 M

0 0.00 0.0

0 0.00 0.0

0 0.00 0.0

0 0.00 0.0

746· 0.89 61

0 0.00 0.0

7201 0.41 81.4

•••• Ratio between prevalent cases at the end of the year and the number of new cases detected during the year <Denominator is based on the exact population estimate 19 907

Figures in ( ) indicate year of latest available data

0.0

20.0

0.0

14.4

21.3

0.0

0.0

0.0

0.0

0.0

0.0

0.0

27.0

14.0

100

3.0

0.0

0.0

0.78

0.0

0.0

0.0

0.0

0.0

0.0

14.4

1.5

0.0

28.6

0.0

0.0

0.0

0.0

0.0

0.0

16.2

0.0

9.35

0.0

0.0

0.0

9.1

2.1

0.0

25

0.0

1{).7

0.0

0.0

32.4

6.7

5.6

0.0

6.1

0.0

25

32.3

0.0

0.0

25.0

liJ

0.0

0.0

2l

5.1

0.0

28.6

0.0

28

0.0

0.0

0.0

0.0

6.3

0.0

7.41

1.3

0.0

1.0

0.81

1.91

0.0

1.25

1.6

1.5

8

0.5

0.56

28

0.98

1.0

2.9

2.0

0.84

0.61

0.0

0.0

0.0

0.0

0.0

1.0

1.41

0.99

0.0

0.71

1.92

0.0

0.0

0.0

0.0

0.86

0.0

1.31

3

Legend

Uio Peoplt!s De1nocra!lt R;;~puL11ic

• 0-0.49 cases per 10 000 (28 countries)

• 0.5-0.99 cases per 10 000 (6 countries)

• 1 or more cases per 10 000 (3 countries)

Northern Mariana Islands • Guam t ..

Federated States of Micronesia

•Palau

Solomon Islands

.. Vanuatu

' .... New Caledonia

Republic of " Marshall Islands ..

.. ~

Nauru

Kiribati

• Tuvalu

• llf Fiji

Leprosy Situation in the Western Pacific Region

at the End of 2005

.. • Tokelau .. • Cook Islands

Wallis and Futuna .. American Samoa

• Samoa

Niue . .. Tonga

... .. . • French Polynes1a

. .. Pitcairn Islands

The designation on this map do not imply the expression of any opinion on the part of the Regional Director concerning the legal status of any country or territory of the delimitation of its frontiers .

PIC group of islands not to scale ,

Note: Shaded areas are outside the WHO Region for the Western Pacific


INTRODUCTION

The Western Pacific Region comprises 37 countries and areas, with an estimated

population of 1.74 billion in 2005. The Region contains both populous countries

such as China and Japan, representing 75% and 7% respectively of the total regional

population, and 22 very small countries and areas, representing 0.5% of the total

population.

Eight countries and areas have populations of more than 10 million and six have

populations between one and 10 million. Of the remaining 23 countries and areas

with populations of less than one million, seven have populations of more than

200 000 and 16 have populations of less than 200 000, of which seven have

20 000 or less. Countries and areas are scattered in the north, west, central, and

south Pacific.

The introduction of multidrug therapy (MDT) for treatment of leprosy in the 1980s

and the adoption of a resolution by the World Health Assembly in 1991 for

elimination of leprosy as a public health problem-considered to be a prevalence

rate of less than one case per 10 000 population-were important landmarks in

combating the disease. Although the elimination goal was achieved at the global

level by the end of2000, a few countries and areas have not reached the elimination

target at their national level. In 1999, the target date for reaching elimination was

extended to 2005, but six countries and areas still failed to attain the elimination

goal.

In the Western Pacific Region, MDTimplementation began in 1985. It reached 10%

coverage in 1988 and almost 100% by 1994, coinciding with a continuous decline

in prevalence rate (Figure 1).

FIGURE 1 Leprosy prevalence rates and multidrug therapy in the Western Pacific Region (1988-2005)

c 2.0 0 100 ~ :; Q. 0 1.5 Q.

0 0 0 0 ....

1.0 ... G> Q.

"! G> 0.5 u c G> 'ii > I!! 0.0 a.. I I I I I I I I I 0

co CD 0 .... N C') 'Of' on co co CD CD CD CD CD CD CD CD CD CD CD CD CD CD .... .... .... .... .... ....

CD ..... co CD 0 .... N C') 'Of' on CD CD CD CD C> C> C> C> C> C> CD CD CD CD C> C> C> C> C> C> .... .... .... ..... N N N N N N

Year

--+- Prevalence rate --o- MDT coverage

~ 0

G> g)

I! G> > 0 u >. Q.

I! G>

= g)

2 ~ :; ::Iii

5

6


ACHIEVEMENTS

The prevalence rate atthe regional level further declined by 5.2%, while the

new case detection rate increased by 14% compared to 2004.

Elimination status was sustained in 33 countries and areas that have attained

elimination, with only three countries and areas (Kiribati, the Marshalllslands,

and the Federated States of Micronesia) still to reach the elimination target in

2005.

National leprosy awareness campaigns launched in Kiribati, the

Marshall Islands, the Federated States of Micronesia, Papua New Guinea,

the Philippines, and Solomon Islands, were assisted and followed up.

• Special projects, such as the knowledge, awareness and practices (KAP} survey,

the health education campaign (HEC), and rapid surveys of endemic pockets,

were implemented in Cambodia, Kiribati, and the Federated States of

Micronesia; and a leprosy elimination campaign (LEC) was implemented in

the Philippines.

A geographic information system (GIS) has been established in VietNam and

Cambodia.

The implementation of the strategy to sustain leprosy services following

elimination, formulated in the 2004 biregional meeting of the WHO Regional

Office for the Western Pacific and the WHO Regional Office for South-East,

was started in Cambodia and VietNam.


EPIDEMIOLOGICAL SITUATION

Table 1 (see page 3) summarizes the latest available data on leprosy by countries

and areas, as of the end of 2005. Of 37 countries and areas, 30 sent data using the

annual statistics form of the WHO Regional Office for the Western Pacific or the

format communicated by WHO Headquarters.The seven countries and areas that did

not send data cover 20.8 million ofthe Region's population, 13 million prevalent

cases and 17 million new cases.

4.1 ELIMINATION AT REGIONAL, NATIONAL AND SUB-NATIONAL LEVELS

Elimination at the regional level was achieved in 1991 with only 15 countries and

areas reaching elimination at their national level, increasing to 35 by the end of

2000. Only two countries in the region, the Marshall Islands and the Federated

States of Micronesia, have yet to achieve elimination. One country, Kiribati, has

failed to sustain elimination since 2004 (up to the end of 2005) due to detection of

a large number of new cases following a leprosy awareness campaign and active

case detection by screening schoolchildren and populations in high endemic pockets.

A country or area with a small population (less than 100 000) that has fewer than

10 registered cases is considered to have achieved elimination (Table 2). To date,

99.98% oft he regional population lives in countries and areas that have eliminated

the disease as a public health problem.

TABLE 2 Distribution of countries as to attainment of elimination target in 2005

Thirty-four countries and areas achieved and sustained elimination, representing 99.9% of the Regional population:

American Samoa, Australia, Brunei, Cambodia, China, Cook Islands, Fiji, French Polynesia, Guam, Hong Kong (China), Japan, the Lao People's Democratic Republic, Macao (China), Malaysia, Mongolia, Nauru, New Caledonia, New Zealand, Niue, the Commonwealth of the Northern Mariana Islands, Palau, Papua New Guinea, the Philippines, the Pitcairn Islands, the Republic of Korea, Samoa, Singapore, Solomon Islands, Tokelau, Tonga, Tuvalu, Vanuatu, VietNam, and Wallis and Futuna

Two countries that did not yet achieved elimination and one country that failed to sustain elimination:

The Marshall Islands, the Federated States of Micronesia, and Kiribati

Sub-national elimination has been reached at the regional level in the Philippines,

at the provincial level in Cambodia, the Lao People's Democratic Republic, and

VietNam, and at the county level (except in a few counties) in China. However,

these five countries contributed 78% of the total prevalent cases in the region at

the end of 2005.

7


8

4.2 NEW CASE DETECTION

There were 7201 new cases detected in 2005, corresponding to a new case detection

rate of 0.413 per 100 000 population compared to 14 674 new cases detected in

1991 with a rate of 0.97 per 100 000 (Table 2); however, there is an increase by

14% as compared to the 2004 data. Four countries contributed 82% of all new

cases detected, with the highest proportion of 44% of all new cases detected in the

Philippines (Figure 2).

FIGURE 2 Distribution of new cases of leprosy detected in 2005

•••• Philippines

China

VietNam

t"~§'~, Cambodia

Papua New Guinea

•••• Other countries

The new case detection rate varied from 0 to 201.6 per 100 000 in 2005. Two

countries have reported case detection rates of more than 10 per 100 000,

with the highest in the Federated States of Micronesia. Another 11 countries

and areas reported case detection rates between 1 and 10 per 100 000. Of the

remaining 24 countries and areas, eight countries and areas reported case

detection rates between 0.01 and 0.99 per 100 000; six countries and areas

reported that no new cases were detected; and eight countries and areas have

not sent in their reports (Figure 3).


FIGURE 3 New case detection rates per 100 000 population in 2005

American Samoa I 4.62

Australia 0.02

Brunei Darussalam (~003) 0.27

Cambodia I 3.o5

China 0.13

Cook Islands 0.00

Fiji I o.47

French Polynesia (2002) I 3.9o

Guam (2001) I 3.54

Hong Kong (China) 0.06

Japan 0.00

Kiribati 34.22

Republic of Korea 0.03

LaosPDR I 2.41

Macao (China) (2003) I 0.22

Malaysia I 1.04

N. Mariana Is. (2003) • 4.95

Marshall Islands 71.01

Micronesia, (Federated States of) ••••••••••••••••••••••••••••• 235.32

Mongolia (2003) 0.00

Nauru (2002) . 7.33

New Caledonia (2003) 1 1.69

New Zealand 0.05

Niue 0.00

Palau - 10.03

Papua New Guinea . 6.47

Philippines I 3.77

Pitcairn Islands 0.00

Samoa I 3.78

Singapore 0.30

Solomon Islands (2003) . 5.23

Tokelau (2003) 0.00

Tonga 0.00

Tuvalu 0.00

Vanuatu 0.00

VietNam 0.89

Wallis and Futuna (2003) o.oo -,

0 I

50 I

100 I

150 I

200 I

250

Note: No cases were detected In Cook Islands, Mongolia, Niue, the Pitcairn Islands, Tokelau , Tonga, Tuvalu, Vanuatu . and Wallis and Futuna.

Since 1991, when the region attained the elimination goaL there was a continuous

decline in the new case detection rate up to 2004; however, a 14% increase was

noted in 2005 (Figure 5 and Table 4). This increase was mostly due to an increased

number of detected new cases in Kiribati, the Federated States of Micronesia, the

Philippines, and Solomon Islands, following intensification of case detection

activities.

9


New case detection includes patients who showed the onset ofthe disease during

2005 (incident cases) as well as in previous years (backlog cases that remained

undetected). The exact proportion of the backlog cases among the new cases is not

known. Case detection is also influenced bytheintensity of programmed activities,

service coverage, and the reporting system, as well as sensitivity and specificity of

the diagnosis. Therefore, the new case detection rate may not represent the true

incidence and degree of transmission of infection in the community.

4.3 PREVALENCE

The prevalent cases decreased from 67 593 in 1991 to 9460 in 2005 and the

prevalence rate dropped continuously from 0.45 per 10 000 to 0.054 per 10 000

in the same period, representing a decrease of 87.4%. The Lao People's Democratic

Republic, Malaysia, and VietNam contributed largely to this latest reduction in the

prevalence rate. Only two countries, China and The Philippines have reported more

than 1000 registered cases in the region.

When comparing rates, as in previous years, some small countries and areas (Kiribati,

the Marshall Islands, and the Federated States of Micronesia) showed serious leprosy

problems (Figure 4 ), though in absolute numbers their contribution to the regional

disease burden was negligible.

FIGURE 4 Distribution of reg istered cases and the prevalence rates per 10 000 for eight countries in the Western Pacific Region (2005)

Cambodia

China

Kiribati

Marshall Islands

Micronesia, (Federated States of)

Papua New Guinea

Philippines

VietNam

10

..., 15

I

10 ' 5

I -I T

0

Registered cases (OOOs)

I

5 I

10 15

Prevalence rate per 10 000 population


4.4 OTHER INDICATORS

4.4.1 MB, CHILD, AND DISABILITY GRADE 2 PROPORTIONS AMONG

NEW CASES

Among new cases detected in 2005, the proportion of Multibacillary (MB), disability

grade 2, and those children younger than 15 years, showed only marginal changes

from 2004.

The proportion of MB cases among new cases detected has an average of 73%,

reaching a peak of81% in 2005. The Philippines, with 94.3%, registered the highest

MB proportion among new cases detected in 2005. This proportion indicates the

magnitude of the potential source of transmission and risk for complications such

as reactions and neuritis which, if nottreated adequately, could lead to disabilities.

China and the Philippines reported the highest number of new cases in 2005.

Visible disability, expressed as grade 2, represented, on average, 13% with a range

of 9% to 15%, between 1994 and 2005, with the lowest rate noted in 2005. The

proportion was high in Cambodia, China, the Lao People's Democratic Republic, the

Republic of Korea, VietNam, and a few other island countries and areas, indicating

delay in detection or self-reporting of cases.

The percentage of new cases involving children younger than 15 years was 7%,

compared to a range of 3%-9% between 1994 and 2005 (Table 3). This perhaps

indicates that recent transmission of infection was in genera lata low level. However,

Kiribati, the Marshall Islands, the Federated States of Micronesia, and Papua New

Guinea have reported high proportions of children among new cases, due to active

case findings, specifically a school survey conducted in 2005, and also may reflect

high level oftransmission, as these are still the countries and areas that have yet to

attain the elimination goal.

TABLE 3 Proportion of MB, disability grade 2, and children below 15 years among new cases (1994-2005)

Year

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

New cases*

No.

10 697 11 906 13 070 13 583 10 587

9482 8360 7409 7187 6165 6195 7201

111 842

Multlbacillary

No. % 8545 80 8027 67 8650 66 9385 69 7216 68 6714 71 6300 75 5708 77 5549 77 4871 79 4902 79 5815 81

81 682 73

Disability grade 2 Children <15

No. % No. % 1232 12 372 3 1822 15 582 5 1637 13 1132 7 2064 15 1076 8 1518 14 887 8 1172 12 882 9 1036 12 647 8 890 12 519 7 867 12 505 7

701 11 430 7 748 12 520 8 673 9 520 7

14 360 13 8072 7

*The numbers are those reported by the countries and areas in the year considered; countries that did not report were not included .

11


12

4.4.2 CASES CURED

Information was not available for cases cured. The proportion of patients who

complete their prescribed treatment regimen on time is a proxy indicator for cure

rates based on cohort analysis, which is not incorporated in the annual report

forms.

4.4.3 PREVALENCE/DETECTION RATIO

On average, the ratio between prevalence and detection was 1.3 with a marginal

decrease as compared to 2004. Twelve-month fixed duration MDTfor MB cases

was introduced in 1997-98, so the ratio should not exceed 1.5 for the countries

and areas that introduced the one-year policy. The ratio was very high in the

Republic of Korea (28.0) and high in Hong Kong (China) (8.0), Malaysia (2.9),

China (1.9) and Singapore (1.9) (Table 1). This indicates that, in these countries

and areas, patients are treated longer than necessary; registers are not updated or

cleaned; patients are irregular in taking their treatment; or a combination of these

factors.

4.5 POST-ELIMINATION TRENDS OF PREVALENCE AND NEW CASE DETECTION RATES

4.5.1 REGIONAL TRENDS

The new case detection rate has varied from 0.97 in 1991 to 0.413 per 100 000 in

2005. The rate has generally remained stable up to 1997 with only small variations

between years. A marked reduction of 23% occurred in 1998 and declined

continuously until2004. Analysis of data from 1991 to 2004 revealed a significant

declining trend in the new case detection rate, reflecting interruption oftransmission

and effective programme coverage and implementation. In 2005, a 14% increase

was recorded as compared to 2004, brought about by increasing detection activities

and a leprosy awareness campaign in the Lao People's Democratic Republic, the

Federated States of Micronesia, the Philippines, and Solomon Islands. Such increase

in case detection rate is temporary or artificial and will taper down in succeeding

years.

The prevalence rate has varied from 0.45 per 10 000 in 1991 to 0.054 in 2005.

The rate has declined continuously following elimination. The rate of decline

has slowed down during the last six years.

With the introduction of a single dose treatment regimen for single lesion and

one-year duration for MB, the duration of the disease has been reduced to

between 1 day and 12 months. As a result, prevalence is converging with

detection.


TABLE 4 Trend of the prevalence and new case detection, Western Pacific Region (1991-2005)

Newly detected cases

Number Rate per 10 000 Number Rate per 1 00 000

1991 1 515 579 67 593 (0.45) 14 674

1992 1 537 199 42 254 (0.28) 13 594

1993 1 560 521 35 145 (0.23) 11 034

1994 1 580 357 38 733 (0.24) 12 643

1995 1 610 291 30 556 (0.19) 11 907

1996 1 628 600 26 275 (0.16) 13 070

1997 1 634 465 23 370 (0.15) 13 583

1998 1 652 781 19 076 (0.12) 10 600

1999 1 672 418 14 195 (0.09) 9494

2000 1 706 434 12 731 (0.07) 8360

2001 1 694 691 11 764 (0.069) 7409

2002 1 706 168 11 035 (0.065) 7187

2003 1 729 924 10 449 (0 .06) 6165

2004 1 743 620 10 000 (0.057) 6195

2005 1 752 283 9460 (0 .054) 7201

FIGURE 5 Trend of prevalence and new case detection rates (1991-2005)

1.2

1

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4.5.2 TRENDS IN SOME COUNTRIES AND AREAS

The prevalence and new cases detection trends in countries and areas with large

populations showed a consistent and continuous decline after reaching the

elimination target of prevalence rate of less than 1 per 10 000 (Figure 6 and

Figure 7).

However, there were wide fluctuations in countries and areas with small populations,

sometime even crossing over the elimination level, espedallyin countries and areas

with populations of less than 500 000 (Figure 8). These trends will be closely

monitored and appropriate actions will be initiated to sustain elimination where

necessary.

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05

PROGRAMME ACTIVITIES

5 .1 STRENGTHENING NATIONAL PROGRAMMES

The 11 countries and areas of Cambodia, China, Kiribati, the Lao People's

Democratic Republic, the Marshalllslands, the Federated States of Micronesia,

Papua New Guinea, the Philippines, Samoa, Solomon Islands, and Viet Nam,

were provided with technical assistance to strengthen programme capability in

planning and implementing special projects, programme review, and planning,

training, and evaluation, between 1996 and 2005. They were the countries

and areas that most benefited from special projects, especially Cambodia and

the Philippines, which achieved elimination in 1998.

Implementing the biregional strategy of sub-national approaches, integration

into general health services, monitoring supervision and surveillance, and

sustaining political commitment and partnership has started this year in

Cambodia and VietNam, and plans were coordinated with the national programme

managers for wider implantation in the coming years.

5.2 SPECIAL PROJECTS

LEC AND SAPEL

In 2005, the WHO Regional Office for the Western Pacific focused its efforts on

health education campaigns and rapid surveys of endemic pockets and screening

of selected populations in Cambodia, Kiribati, the Federated States of Micronesia,

the Philippines, and Solomon Islands that resulted in the detection of 330 new

cases. These countries and areas, with the assistance of WHO and

nongovernmental organizations (NGOs). and through their own resources,

developed and implemented LECs and SAPELs.

The first such projects were implemented in 1996; by 2004, 86 projects have

been completed, covering 42 million people and detecting 5208 new cases.

The figures represented 7% ofthe cumulative new cases detected in the region

during these nine years. The countries and areas that most benefited from

these projects were Cambodia and the Philippines, giving coverage of 97% and

26%, respectively, of their total populations.


15

16


5.3 OTHER SPECIAL PROJECTS

Kiribati, the Marshall Islands, and the Federated States of Micronesia, which had

high prevalence rates, implemented special projects between 1996 and 2000 to

accelerate and achieve the elimination goal. The projects consisted oftotalor selected

population surveys and administration of preventive therapy, consisting of

Rifampicin-Ofloxacin-Minocycline (ROM) combination for adults and rifampicin alone

for children younger than 15 years once or twice at yearly intervals to all healthy

people during screening in Kiribati and in the Federated States of Micronesia, and

family contacts of cases in the Marshall Islands. During screening, a large number of

new cases were detected and treated with MDT. After an initial rise, both prevalence

and case detection rates declined following implementation of the projects in all

three countries and areas.

In addition to conducting orientation training workshops on the elimination of

leprosy, and case detection in endemic pockets, information, education, and

communication activities (IEC) were intensified in all the three countries and areas

in 2002 and followed up with the launching of national leprosy awareness

campaigns.

In the Federated States of Micronesia, screening of 16 123 children in schools,

448 family contacts of cases, and 5344 populations in high endemic villages have

resulted in detection of 44 new cases in 2005.

5.4 POST-ELIMINATION SURVEILLANCE SYSTEM

The guidelines for the post-elimination surveillance system were developed in 1991

in the WHO Regional Office for the Western Pacific. The system was based on

establishment referral centres for case diagnosis and management, referral of

suspected cases from the periphery, notification of individual cases to the central

level, mapping of the notified cases, integration of leprosy information into the

general health information system, sustaining leprosy awareness in the community,

and general health staff and evaluation. A pilot project of post-elimination

surveillance system was started in selected provinces of Cambodia in 2000 and

extended to cover all provinces by 2004 following periodic evaluation.

The pilot projects that were started in 2001 in selected provinces of the Lao People's

Democratic Republic and Viet Nam were continued. The geographic information

system (GIS) developed in Cambodia and VietNam is being utilized in identification

of endemic pockets at the peripheral level.

The concept, guidelines, and activities of the post-elimination surveillance are

included as strong pillars in the biregionalstrategy, which is now being implemented.

5.5 COLLABORATION WITH OTHER PARTNERS

Continuous collaboration has been maintained with Sasakawa Memorial Health

Foundation (SMHF), which funded the activities implemented in Cambodia, the

Federated States of Micronesia, and Papua New Guinea. Likewise, a partnership

programme with the Pacific Leprosy Foundation has been strengthened, assisting

south Pacific countries and areas, especially Kiribati, Samoa, Solomon Islands,

Tonga, and Vanuatu. Coordination meetings with governments and NGOs for leprosy

elimination were held ih Cambodia, China, the Lao People's Democratic Republic,

the Philippines and VietNam.


17


ISSUES AND CHALLENGES

18

(a) Achieving the goal of elimination of leprosy as a public health problem

in the remaining countries of Kiribati, the Marshall Islands, and the

Federated States of Micronesia in the coming years.

(b) In some countries and areas, accessibility is restricted because of the

poor communications and vast distances (small islands countries and

areas, for instance). In others (such as Papua New Guinea and the

Philippines), some places are inaccessible because of security concerns.

Therefore, patients living in difficult-to-reach places now represent

an important proportion of the total caseload and it will be harder to

detect these patients.

(c) Few countries and areas (China, Hong Kong [China], Malaysia, the

Republic of Korea, and Singapore) still have a prevalence and detection

ratio higher than 1.5, indicating that patients are treated longer than

necessary and that they are inflating the prevalence. Moreover, the

implementation of the 12-month duration regimen for MB is progressing

slowly in certain areas.

(d) Countries and areas such as Cambodia and the Lao People's Democratic

Republic, which reached elimination by 1998, are still dependent to a

large extent on external resources in running their programmes to

sustain elimination.

(e) There are a large number of patients who were declared cured but

require care after cure for the treatment of complications such as

reactions and plantar ulcers. Similarly, there is a large number of cured

cases who need physical and socio-economic rehabilitation because of

disabilities developed from the disease. The recognition and

management of post-MOT reactions and the progressions of leprosy

disabilities affects the quality of life and social re-integration of

patients.

(f) The epidemiology of the disease itself is still a challenge. To date, there

is no effective way to measure the level of infection and incidence of

the disease in the community. This is complicated by very long

incubation period of the disease and the process of self-healing of

many single lesions, as well as the tendency for the patients to hide

the disease because of social stigma.

(g) There is a fast-turnover of skilled or trained staff at the peripheral level,

which poses difficulties in ensuring wider coverage of leprosy services in

currently underserved population groups and in continuing and sustaining

quality leprosy services in some countries and areas.

(h) Strengthening integration of leprosy services into the general health

services through capability building is needed to ensure quality diagnosis,

treatment, and management of complications, particularly in previously

endemic countries and areas.

(i) Sustained political commitment and adequate resources from national

gove~nments is needed; partnerships and collaboration with NGOS are

needed to pursue quality leprosy control activities, further reduce the

disease burden, and support sodo-economic rehabilitation .

U) Continuing public awareness is needed through sustained advocacy and

IEC activities. Early self-reporting of cases in the community can be

promoted by spreading awareness that leprosy is a curable disease with

MDT drugs that are available safe and free at health centres; further, IEC

activities should emphasizethatsodalstigma and discrimination of people

affected with leprosy has no place in the sodety today.


19


FUTURE PRIORITIES AND ACTIVITIES

7.1 COUNTRIES AND AREAS IN WHICH LEPROSY HAS NOT BEEN ELIMINATED (0.01 °/o OF THE REGIONAL POPULATION)

The trend of the prevalence rates for the last 10 years in the Marshall Islands

and in the Federated States of Micronesia has declined after an initial rise due

to special projects implementation (Figure 9). However, it stagnated for the last

few years. Due to high baseline endemicity, the long incubation period ofthe

disease, and other environ mental and socio-economic factors, the disease may

have persisted, and needs more time for reaching elimination, as compared to

other countries and areas.

These two countries and areas will be further supported to continue elimination

activities, including screening of high-endemic pockets, training, IEC, and

strengthening of technical and managerial skills, particularly on integration

and research. The progress towards attaining the elimination goal will be closely

monitored and supervised.

FIGURE 9 Trend of prevalence rates in two countries that have not yet achieved the elimination target in the Western Pacific Region

20

0 0 0 0 .... ... Cll c. .! ~

50 -

40 -

30 -

20 -

10 -

o.., 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Year

- Marshall Islands -+- Micronesia

7.2 COUNTRIES AND AREAS THAT ACHIEVED ELIMINATION AT THE NATIONAL LEVEL

7 .2.1 IMPLEMENTATION OF THE BIREGIONAL STRATEGY TO SUSTAIN

LEPROSY SERVICES FOLLOWING ELIMINATION

The strategy document was sent to the national governments for their adoption,

followed by an extension of technical support for development of country-specific

action plans for implementation of the strategy, focusing on total integration of

leprosy services with general health services. Countries and areas will be prioritized

based on situation analysis with reference to elements of the strategy and the

number of cases being reported. Strategy implementation was piloted initially in

two countries and areas (Cambodia and Viet Nam) in 2005 and preparation is

underway to implement it in China, Papua New Guinea, and the Philippines. Advocacy

to sustain political commitment and partner support was pursued vigorously for

the required resources.

7.2 .2 VALIDATION OF LEPROSY ELIMINATION

Validation or certification of elimination is not done, since cost-effective and

practical tools are not readily available. However, periodic independent external

assessment using Leprosy Elimination Monitoring (LEM) protocol will help to

evaluate the programme performance. Efforts will be made to review the LEM

document for its adaptation to suit low and very low prevalent situations and

apply the same to validate programme achievements, particularly identifying

main indicators for monitoring progress and status of leprosy control activities

under low endemicity.


21


RESOURCE REQUIREMENTS

22

To carry out the leprosy strategic plan, US$ 300 000 in external assistance is

required annually for the coming few years. Furthermore, assistance provided by

NGOs to national governments should be kept at current levels, particularly as the

newly-developed strategy to sustain quality leprosy services is introduced and

implemented in all countries and areas, toward a functional and complete integration

of leprosy control activities into general health services.

This publication can also be downloaded at:

http:/ fwpro.who.int

United Nations Avenue, 1000 Manila, Philippines Tel. No. (632) 528-8001 • Fax No. (632) 521-1036 • Email: [email protected]

Website: http://www.wpro.who.int •

ISBN 978 92 9061 315 2

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