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Integrated Program for the
Eradication of Poliomyelitis in Macau

= Certification of the Eradication =

It is better to report
A case that is not polio
Than to risk missing
A case that could be polio

World Health Organization

summary

 

Propounder

Epidemiological Surveillance Technical Unit,  Medical and Health Department

Coordination

Committee for Certification of the Eradication of Poliomyelitis,  Epidemiological Surveillance Technical Unit

Development

Health Centres,  Government Hospital (Centro Hospitalar Conde S. Januário)  and  Kiang Wu Hospital

Assessment

Committee for Certification of the Eradication of Poliomyelitis,  Epidemiological Surveillance Technical Unit

Consultancy

World Health Organization (Regional Office for the Western Pacific Region)

Generic principles

The program should be considered (1) an elementary, effectively integrated and permanent component of the Macau health system including public and private health care providers and institutions, and (2) a contribution for the continuous improvement of communicable disease surveillance system, either passive or active, including the desirable timeliness, completeness and accuracy of the reporting of notifiable diseases. It should be assessed periodically and readjusted according to its development / evolution.

Certification of eradication

The Epidemiological Surveillance Technical Unit, as management structure, has overall responsibility for certification of poliomyelitis eradication. Staff of this unit carry out the duties of the secretariat for the Committee for Certification of Poliomyelitis Eradication.

Temporal horizon

Three complete years, starting on the 1st of November 1997, with yearly assessment and reporting to the World Health Organization.

Aim

To contribute for the elimination of the clinical disease (poliomyelitis) and the eradication of wild poliovirus in the world (certification: year 2003).

Regional goal

To certify the eradication of poliomyelitis in the Western Pacific Region by the end of the year 2000. To reach this goal, there must be three consecutive years free of poliomyelitis in all countries and territories of the region.

Territorial goal

To warrant the interruption of indigenous transmission of wild poliovirus in Macau, and reduce the risk of its importation. To reach this goal, there must be, at least, three consecutive years free of indigenous wild poliovirus (1998,1999 and 2000).

Target population

The program target population comprises (1) all children up to age of 15 years, and (2) all health care providers in public and private institutions, mainly general practitioners from health centres and pediatricians from hospitals (emergency, external consultation and infirmary).

Structure

The specific program is divided in two operational stages and includes five main components, as stated in the global Plan of Action approved by the Macau Committee for Certification of the Eradication of Poliomyelitis and the Director of the Medical and Health Department:

Information campaign and educational sessions for the medical community, with audio-visual materials on (1) general topics concerning the prevention, control, elimination and eradication of poliomyelitis, and (2) specific topics related with the active surveillance and investigation of "acute flaccid paralysis" (AFP). These activities are complemented with the preparation and distribution of relevant bibliography;

Five year retrospective record review to search for paralyzed children and cases of suspected poliomyelitis/AFP (hospital based);

Key physician reporting in all health centres, including the prompt reporting of all suspected cases of poliomyelitis/AFP, as well as reporting "zero cases of AFP" on a weekly basis;

"Active surveillance of AFP" in public and private hospitals, respectively in Centro Hospitalar Conde S. Januário (CHCSJ) and Kiang Wu (KW). This project refers to the rapid AFP case investigation, including the collection and analysis of adequate stool samples;

Management of the poliomyelitis immunization program, within the context of the Macau Immunization Program, including (1) routine immunization activities with oral trivalent poliovirus vaccine (OPV), (2) monitoring vaccination coverage levels in all districts and counties, and (3) aggressive outbreak response immunization with OPV, on a territorial scale, whenever necessary (for example, if any case of wild poliovirus associated poliomyelitis, imported or indigenous, is detected).

Eradication strategies

The program considers two main strategies and a supplemental one, based on the global eradication initiative launched by the World Health Organization (WHO).

The main strategies are:

improving routine vaccination coverage. High primary vaccination coverage (>95%) with three doses of OPV should be achieved for infants in every county. High vaccination coverage with four doses of OPV (>90%) should be achieved for children less than 2 years of age in all districts; and

improving surveillance of suspected polio cases through the effective implementation of active surveillance for Acute Flaccid Paralysis. Timely and accurate reporting is a primary objective on disease surveillance. Reliable active surveillance is essential for polio eradication and active surveillance of suspected poliomyelitis aims to detect all cases of AFP, so that they can be investigated immediately. With effective active surveillance, areas can be identified where wild poliovirus continues to circulate and the progress of eradication activities can be monitored.

The supplemental strategy comprises a prompt outbreak response through the administration of a supplementary dose of OPV to all children under the age of 15 years. Mass vaccination or high risk vaccination strategies can be implemented, if justified.

Operational objectives

The program consider intercalate (yearly) and global assessments, including the monitoring of the quality of AFP surveillance and laboratory services. The indicators and performance targets are as follows:

 

Indicators

1998

1999

2000

1.

Non-polio AFP cases per 100,000 population aged less than 15 years

>1

>1

>1

2.

Percentage of routine surveillance sites that provide routine reports (including "zero cases" weekly reports) on time

>80%

>85%

>90%

3.

Percentage of AFP cases that are correctly investigated

>80%

>85%

>90%

4.

Percentage of AFP cases that are investigated within 48 hours of notification

>80%

>85%

>90%

5.

Percentage of AFP cases with a follow-up examination for residual paralysis, at 60 days after the onset of paralysis/weakness

>80%

>85%

>90%

6.

Percentage of AFP cases with 2 "adequate" stool samples collected 24-48 hours apart, but within 14 days after onset of paralysis

>80%

>85%

>90%

7.

Percentage of specimen results sent from the WHO-accredited poliovirus laboratory, within 28 days of receipt of the specimen in the lab

>80%

>85%

>85%

8.

Percentage of intratypic differentiation results available within 90 days of the collection of the stool specimens

>80%

(wc)

>85%

(wc)

>85%

(wc)

9.

Percentage of stool specimens from which a non-polio enterovirus (v.g. coxackie, ECHO, EV 71) is isolated in the WHO-accredited laboratory

>10%

>10%

>10%

10.

OPV primary vaccination coverage (3 doses) in children less than 12 months old

>90%

>95%

>98%

11.

OPV coverage with the 1st booster (4th dose) in children aged less than 2 years

>88%

>92%

>95%

12.

OPV coverage with the 2nd booster (5th dose) in children aged less than 6 years

>88%

>92%

>95%

13.

OPV coverage with the 2nd booster (5th dose) in children aged less than 12 years

>85%

>88%

>90%

14.

Screening and investigation of AFP cases found in S. Januário and Kiang Wu hospitals (admission records), between January 1993 and December 1997

EA

---

---

15.

Information and educational campaigns for the medical community (public and private clinics)

EA

EA

EA

16.

Aggressive outbreak response immunization with OPV, whenever necessary, either through population based or high-risk strategies

EAwc

EAwc

EAwc

 

EA: effective accomplishment;  wc: whenever convenient

 

Human resources

Considering the unquestionable benefits resulting from the successful implementation of the program and the full achievement of its goals, the necessary human resources are meaningless in terms of costs (only opportunity costs can be considered). The human resources and their generic tasks are summarized as follows.

Besides the professionals of the Macau Committee for the Eradication of Poliomyelitis (CEP), and the collaborating physicians (theoretically all Macau practitioners should be involved), eight key physicians are to be designated for the screening and reporting of AFP in health centres (one key physician in each health center). The key physicians are also responsible for the prompt reference of AFP cases to the hospital pediatric units.

During the first stage of the program, one or two additional doctors in each hospital are necessary to help the "five year retrospective review", searching for records of AFP/suspected poliomyelitis cases. These doctors may be residency and/or general internship fellows.

The full investigation of AFP cases is carried out under the supervision of the hospital CEP coordinators (one in each hospital). Whenever necessary, the expert advice and orientation of a neurologist is expected. The virus isolation and characterization are performed by a virologist in the WHO-accredited laboratory in Hong Kong (Queen Mary Hospital). The transport of samples to Hong Kong, via jetfoil, is made by the staff of the Public Health Laboratory (one person) under the supervision of its director.

As the immunization activities are scheduled to be routinely performed in hospitals and health centres (eleven units), including the school vaccination mobile teams, no additional human resources are necessary. Considering the unlikely occurrence on an outbreak, eight mobile teams (one per health center), each with two nurses and one car driver, will carry out the vaccination of the community or its high risk groups (mass vaccination or mopping-up).

Constraints

All possible constraints should be considered relative and mainly resulting from the lack of motivation and will of the medical community, to co-operate with the WHO eradication initiative.

The lack of an effective political commitment and the insufficient sensibility of the medical community to recognize the importance and benefits resulting from the effective control of poliomyelitis in Macau, as well as its elimination in the WHO-WPR and eradication in the world, are also possible constraints.

The transportation of stool samples to the laboratory in Hong Kong can also rise some problems related with stool desiccation and the strength of the cold chain; non-timely sending of laboratory results is another potential constraint.

The non-attainment of the desirable vaccination coverage, as stated in the operational objectives section, and a non-prompt outbreak response are also potential constraints to the success of the program.

Considering the structure of the program itself and some specific tasks related with the motivation of health professionals, the widespread of relevant information and the educational campaigns to guarantee an adequate performance, most major constraints are expected to be overcome.

Estimation of costs

Regarding the necessary human resources, only opportunity costs may be considered. As the stool samples are to be analyzed free of charge by the WHO-accredited laboratory in Hong Kong, up to twenty samples per year, only direct and some additional costs can be estimated.

For the immunization program, and bearing in mind the previous specific vaccination coverage objectives, the total direct costs for the acquisition of OPV (MOP1.30 per dose) are expected to not exceed MOP221,000.00 (less then MOP74,000.00 per year).

Considering (1) the average unit price of flasks for the collection and transport of one pair of stool samples per AFP case detected, (2) the estimated number of trips to Hong Kong (up to twenty per year), (3) the printed informational materials and audio-visuals for the educational campaigns, and (4) the specific forms for reporting and investigation of AFP cases, the global costs for the three year program are expected to not exceed MOP30,000.00 (average of MOP10,000.00 per year):

flasks for the collection and transport of stool samples: MOP60.00 per year (unit price: MOP1.50);

isothermal containers with icepacks for the transport of stool samples flasks: MOP1,040.00 for the program total length (unit price: MOP130.00);

trips to Hong Kong including the jet-foil tickets and taxi fees: MOP8,400.00 per year (one two-way jet-foil ticket: MOP320.00; each taxi fee: MOP100.00);

printed informational materials and audio-visuals: MOP1,000.00 for the full length of the program; and

reporting and investigation forms: MOP600.00 per year.

The total direct and additional costs related with the implementation and fulfilment of the overall program are estimated in MOP251,000.00 (less then MOP83,700.00 per year).

Major benefits

The medium and long-term major benefits resulting from the effective implementation and success of the program, and translated by the elimination of clinical disease and eradication of wild poliovirus, are:

strengthening Primary Health Care services by developing effective and efficient preventive services;

greater reduction in avoidable death, illness and long-term disability, than with routine immunization;

savings in the cost of treatment and rehabilitation as well as in intangible costs, suffering and economic loss to families; and

savings by eventually stopping polio vaccination in the future.

The primary aim of this Poliomyelitis Eradication Program is to provide a guide to medical doctors and other health personnel involved in polio eradication efforts, for setting up and carrying out polio control and eradication activities, including its certification, at all levels of the Macau health system.

As a complement of the Plan of Action, approved by the Macau Committee for the Eradication of Poliomyelitis (CEP), the director of the Medical and Health Department, and the World Health Organization Regional Office for the Western Pacific, it particularly emphasizes issues related to enhanced/active surveillance. Immunization activities are not described in detail, but health care providers are requested to follow the «Macau Immunization Program: Normatives and Guidelines» (published in chinese and portuguese – Programa de Vacinação de Macau: Normas de Vacinação e Orientações Técnicas)

The surveillance case definitions, diagnostic aids and protocols on the following pages should be used for the (1) reporting of all AFP cases (health centers and hospitals), (2) five year retrospective review of potential AFP cases (hospitals), and (3) screening and investigation of AFP cases in all children and adolescents less than 15 years old, even when poliomyelitis is not suspected.

Health personnel should always bear in mind that "it is better to report a case that is not polio, than to risk missing a case that could be polio". All AFP cases should be reported and investigated according to the procedures outlined.

Surveillance case definitions

Diagnostic aids

Classification schemes

Protocol 1: Retrospective Record Review for Acute Flaccid Paralysis

Protocol 2: Active Surveillance of Acute Flaccid Paralysis

Protocol 3: Other Program Components:

Key physician reporting in health centers
Use of the poliovirus laboratory network
Immunization

Bibliography

© Fernando Costa Silva, 1999