South-East Asia Regional Conference on Epidemiology

The use of epidemiological data to monitor
and evaluate programme performance
James Chin
A basic public health question is: how effective or successful are infectious disease prevention and
control programmes in reducing infection, disease and death rates? The answer to this question
depends on: (1) how well a prevention/control programme implements the programme’s preventive
measures (i.e. programme performance), and (2) how effective preventive measures and/or treatment
for a specific infectious disease agent may be. Programme performance is measured by how timely,
competently and completely preventive measures or interventions are implemented. On the other
hand, programme effectiveness or success is measured by reductions in infection, disease or death
rates that can be specifically attributed to programme efforts.
The effectiveness of preventive measures for any specific infectious disease agent can range from
being marginally effective to highly effective. In addition, the epidemiology and natural history of
infectious disease agents are all uniquely different and the effectiveness of preventive measures for
each agent can also vary greatly depending on when these are implemented, i.e. during the early part
of an epidemic, peak epidemic, post-epidemic, or the endemic phase of transmission. It needs to be
recognized that even perfect programme performance will not significantly reduce infection, disease
and/or death rates unless available preventive measures and/or treatment are effective.
Evaluating the effectiveness or success of infectious disease prevention/control programmes
therefore requires: (1) evaluating programme performance; (2) knowing the epidemiology of each
infectious disease agent, including whether the incidence of new infections is increasing, decreasing
or is stable; and (3) having effective preventive measures and/or treatment. This paper evaluates the
effectiveness of global prevention/control programmes for measles, tuberculosis (TB), HIV/AIDS
and influenza.
Measles
The effectiveness of a measles programme can be simply monitored and evaluated by routine
surveillance data (measles disease and death rates) and routine programme data (measles vaccine
coverage rates). The United Nations goal of reducing the number of global measles deaths that
occurred in 2000 by 90% within a decade (i.e. by 2010) has almost been reached in 2009 by the
immunization of nearly 700 million children through large-scale vaccine campaigns and increased
routine immunization coverages. The only WHO region that may not reach this goal is the <strong>South</strong>-
<strong>East</strong> <strong>Asia</strong> Region, primarily because of poor programme performance in India where less than half of
annual birth cohorts have received measles vaccine(1).