I am grateful to IAPSM for inviting me to deliver this prestigious oration. All of
you are familiar with the life and work of Dr. Harcharan Singh, who was a great teacher
of Preventive and Social Medicine. He also made significant contributions to Indian
public health while working with the Planning Commission of India. I have heard him
speak only once and that was when he came to my institution to address the faculty.
He was a very good orator. I still remember him emphasizing the role of knowledge
in changing attitudes and behaviors. That, to him, was the key approach in public
health.
I would like to elaborate on how this key public health approach has helped in controlling
HIV in India as well as in several other countries. HIV appeared as a new disease
in the early 1980s. In 1986, it was identified among some sex workers of Chennai.
By the 1990s it had spread to every nook and corner of India, threatening the socioeconomic
stability of the region. HIV posed a formidable challenge to public health. The use
of the traditional public health tools of epidemiological surveillance made it possible
to identify vulnerable population groups and geographical areas. AIDS case surveillance
provided valuable information. The heterosexual transmission route, and especially
sex work, was identified as the major mode of transmission in this country and this
paved the way for the launch of large-scale preventive efforts.
HIV spread rapidly in many countries of Africa in a short period of time. The first
victims were sex workers; from them it spread to their clients and, finally, to the
wives of these clients. Going by the experience in Africa, it was predicted that by
2015 there would be about 5-10 million cases of HIV in India. However, there were
a few people who disagreed with these figures; notable among them was Dr. N. S. Deodhar,
former Director of All India Institute of Hygiene and Public Health, Kolkata, who
predicted that HIV would never affect large populations in India as sexually transmitted
infections (STIs) never had a high incidence in this country. However, despite limited
information, the epidemiological projections provided the basis for advocacy that
generated unprecedented political will and financial resources.
The need for launching organized social action, the cornerstone of public health approach,
led to the establishment of the National AIDS Control Organization (NACO) in India
and UNAIDS at the United Nations for coordinating the actions not only in health ministries
but in all relevant sectors. As there was no drug or vaccine that could prevent or
treat the infection, prevention by behavior change, a key public health approach,
occupied central position in the National AIDS Control Program. Behavior change interventions
are still a major focus in this program. Adoption of the health promotion approach
provided an enabling environment to communities for behavior change; this was backed
by supportive policies recognizing human rights as a core value.
The sentinel surveillance system which came into being in the late 1990s provided
an excellent opportunity for tracking not only AIDS-related deaths, but also HIV infection
and sexual behaviors in different population groups and geographic areas. Multiple
sources of information–e.g., cause-specific mortality rates from the sample registration
system (SRS), sentinel surveillance of HIV infection and sexual behaviors, and household
surveys in representative populations–have helped in constructing a realistic picture
of the epidemic in India. The key question, however, is whether there is a change
in HIV or STI incidence. Can the change be explained by the presence of some unknown
bias or confounder? And if there is a change, what is causing the change? Is the change
in behavior due to mass media campaigns that are directed at the general population
or due to the targeting of the behavior change interventions to high-risk groups?
Biological and behavioral surveillance should be able to provide the answers to these
questions.
Epidemiological analysis of HIV sentinel surveillance provided the first indication
of the declining trend in HIV prevalence among young pregnant women in some of the
Southern states. A similar trend was observed among young male STI clinic attendees.
This observation was shared with the public health community by a publication in the
Lancet in 2006. However, eminent public health physicians and epidemiologists from
leading institutions of India attributed the observed declines to various biases or
confounders. Poor coverage of antenatal clinics in northern India, expansion of the
surveillance to rural areas, and nonrepresentation of older women were proposed as
alternate explanations. This constructive criticism led to further analysis, which
included analysis of surveillance data up to 2007; the results confirmed the earlier
observation. However, the search for bias and confounding continues in the true spirit
of epidemiological inquiry.
Stratified analysis revealed similar HIV declines when analysis was restricted to
sites that were consistently sampled throughout the last 8 years. Illiterates and
rural residents showed a similar trend. HIV decline was also seen among male STI clinic
attendees. Syphilis prevalence among young pregnant women and young men attending
STI clinics also showed a similar trend. The decline in HIV and STIs seems to be real
and cannot be explained by bias or confounding or change in the characteristics of
host or agent. The most likely reason for the decline is a change in the sexual behavior
of key population groups, i.e., sex workers and their clients. Analysis of causes
of death from 2001-2003 by verbal autopsy and the third National Family Health Survey
also support the low HIV prevalence estimates in India.
Behavior surveillance surveys provide valuable information. It is well known that
due to the social desirability bias in face-to-face interviews, females tend to underreport
sex with a male other than their regular partner and, similarly, males also underreport
having sex with another male. Nevertheless, trends in sexual behaviors can be assessed
using less-than-perfect interview methods. Analysis of behavior surveillance surveys
for the high- and low-HIV-prevalence states indicate that the prevalence of multi-partner
sex has declined to some extent and safe sex practices have improved in the high-
as well as low-prevalence states. This is also corroborated by sex behavior surveys
of female sex workers and their clients. The number of sexual partners has declined
in the general population for both males and females, though those in the upper tail
of the distribution may not have changed that much. Similarly, the number of paying
sex partners of female sex workers shows a decline. The clients of female sex workers
have also reported a decline in the number of paid sex partners though, again, the
change is less pronounced in the upper end of the distribution. This indicates that
a small minority still engages in unsafe sexual behavior, which still provides a niche
for propagation of HIV. Overall, safe sexual practices have become a norm in both
high- as well as low-HIV prevalence states. A decline in the prevalence of HIV has
also been noted among female sex workers. Small cross-sectional and cohort studies
in Kolkata and Pune, respectively, confirm this trend. However, the epidemic continues
to rage among men having sex with men and in injecting drug users–the risk groups
that were neglected in the past.
Knowledge of local HIV epidemiology is essential for choosing the appropriate response.
HIV epidemiology varies a lot in the country, not only between states but also between
districts and even within the district. The size of HIV sentinel surveillance data
at the district level is not sufficiently large to guide local action; hence, program
data from the Integrated Counseling and Testing Centers from STI patients, pregnant
women, voluntary blood donors, and antiretroviral therapy (ART) clinic attendees should
be analyzed. Recently, we found that HIV prevalence from the Prevention of Parent
to Child Transmission (PPTCT) sites is not significantly different from that of sentinel
surveillance sites. PPTCT data is of sufficient size to measure trends in smaller
geographic areas and population groups provided biases are carefully evaluated.
Essentially, in India the HIV epidemic remains concentrated in high-risk groups such
as injecting drug users and male and female sex workers. To contain the epidemic,
it is essential to map high-risk groups so as to target preventive interventions using
the health promotion strategy. So far, the response to the HIV epidemic had been a
population-wide biomedical-oriented preventive approach and this has paid off. However,
to root out the causes of HIV spread, the social determinants need to be tackled.
No one knows better than us that the origin of disease lies in the socioeconomic conditions
in which people live and work; therefore, social structures and systems need to be
challenged if we are to have policies that favor health and wellbeing. A society that
generates a large number of single male migrant workers will give rise to a demand
for sex work. Therefore, social action is needed to create a just and humane social
system that will generate less disease.
The health promotion approach as described in the Ottawa Charter combines health education
and healthy public policies. Health is not only an individual responsibility but also
a social one. Asking people to change without, at the same time, bringing about a
change in social policies, is not ethical. Success depends on individual and community
empowerment. Building healthy policies requires creation of a supportive environment
for community action, including development of skills for behavior change. Public
health professionals need to acquire skills for advocating changes in the policies
that support behavior change by making healthy choices the easier choices. Rudolf
Virchow, the father of social medicine, once said ‘epidemics are a reflection of the
disturbances in the social system,’ ‘medicine is a social science,’ and ‘politics
is nothing but medicine on large scale.’ This explains the importance of the work
that needs to be done at the policy level; unfortunately, at present, it is not getting
due emphasis in our work.
HIV is down, but not yet out. All those who are infected will continue to need care
for a number of years. According to current estimates about 25 lakh people are infected
with HIV and about 2.2 lakh are on ART. As the number of persons needing treatment
increase in the near future, it will be difficult to run the testing and treatment
service as a vertical activity; hence, steps must be initiated to integrate care and
support activities within the general health services. For sustaining the gains achieved
so far, the AIDS control program should focus its attention on the social determinants
of HIV, while continuing to target primary prevention in vulnerable communities and
geographic areas.