HIV epidemic, a formidable challenge to public health

The global HIV epidemic has emerged as a formidable challenge to public health, development and human rights. In most of the countries affected by HIV, it has eroded improvements in life expectancy and mortality. In just 27 years, HIV has spread relentlessly from a few widely scattered "hot spots" to virtually every country in the world. Nearly twenty-seven years of experience with HIV prevention and more than ten years of experience with effective antiretroviral therapy have produced mountains of evidence about how to prevent and treat HIV.

At the end of 2010, an estimated 34 million people [31.6 million-35.2 million] were living with HIV worldwide, up 17% from 2001. This reflects the continued large number of new HIV infections and a significant expansion of access to antiretroviral therapy, which has helped reduce AIDS-related deaths, especially in more recent years.

The number of people dying of AIDS-related causes fell to 1.8 million [1.6 million-1.9 million] in 2010, down from a peak of 2.2 million [2.1 million-2.5 million] in the mid-2000s. A total of 2.5 million deaths have been averted in low- and middle-income countries since 1995 due to antiretroviral therapy being introduced, according to new calculations by UNAIDS. Much of that success has come in the past two years when rapid scale-up of access to treatment occurred; in 2010 alone, 700 000 AIDS related deaths were averted.

The proportion of women living with HIV has remained stable at 50% globally, although women are more affected in sub-Saharan Africa (59% of all people living with HIV) and the Caribbean (53%).

There were 2.7 million [2.4 million-2.9 million] new HIV infections in 2010, including an estimated 390 000 [340 000^50 000] among children. This was 15% less than in 2001, and 21% below the number of new infections at the peak of the epidemic in 1997.

The number of people becoming infected with HIV is continuing to fall, in some countries more rapidly than others. HIV incidence has fallen in 33 countries, 22 of them in sub-Saharan Africa, the region most affected by the AIDS epidemic.

Regional variations
Sub-Saharan Africa remains the region most heavily affected by HIV. In 2010, about 68% of all people living with HIV resided in sub-Saharan Africa, a region with only 12% of the global population. Sub-Saharan Africa also accounted for 70% of new HIV infections in 2010, although there was a notable decline in the regional rate of new infections. The epidemic continues to be most severe in southern Africa, with South Africa having more people living with HIV (an estimated 5.6 million) than any other country in the world. Almost half of the deaths from AIDS-related illnesses in 2010 occurred in southern Africa. AIDS has claimed at least one million lives annually in sub-Saharan Africa since 1998. Since then, however, AIDS-related deaths have steadily decreased, as free antiretroviral therapy has become more widely available in the region.

The total number of new HIV infections in sub-Saharan Africa has dropped by more than 26%, down to 1.9 million [1.7 million-2.1 million] from the estimated 2.6 million [2.4 million-2.8 million] at the height of the epidemic in 1997. In 22 sub-Saharan countries, research shows HIV incidence declined by more than 25% between 2001 and 2009. This includes some of the world's largest epidemics in Ethiopia, Nigeria, South Africa, Zambia and Zimbabwe. The annual HIV incidence in South Africa, though still high, dropped by a third between 2001 and 2009 from 2.4% [2.1%-2.6%] to 1.5% [1.3%-1.8%]. Similarly, the epidemics in Botswana, Namibia and Zambia appear to be declining. The epidemics in Lesotho, Mozambique and Swaziland seem to be leveling off, albeit at unacceptably high levels.

HIV and AIDS in Asia
In Asia, the rate of HIV transmission appears to be slowing down: the estimated 360 000 [300 000-450 000] people who were newly infected with HIV in Asia in 2010 were considerably fewer than the 450 000 [410 000-500 000] estimated for 2001. Although the rate of HIV prevalence is substantially lower in Asia than in some other regions, the absolute size of the Asian population means it is the second largest grouping of people living with HIV. The incidence of HIV infection in South and South-East Asia appears to have peaked in the mid-1990s (at 440 000^65 000 people newly infected annually) and decreased markedly since then to about 270 000 [230 000-340 000] people acquiring HIV infection in 2010. In India, the country with the largest number of people living with HIV in the region, new HIV infections fell by 56%. About 4.8 million [4 300 000-5 300 000] people were living with HIV in Asia in 2010, 11% more than the 4.2 million [3 800 0001 600 000] in 2001.

The prevalence of HIV among key populations at higher risk of infection - notably sex workers, people who inject drugs and men who have sex with men - is high in several Asian countries although over time, the virus is spreading to other populations. The overall trends in this region hide important variations in the epidemics, both between and within countries. In many Asian countries, national epidemics are concentrated in relatively few provinces. In China, for example, five provinces account for 53% of the people living with HIV, while a disproportionately large share of Indonesia's burden is found in its Papua and West Papua provinces.

An estimated 310 000 [260 000-340 000] people died from AIDS-related causes in 2010 - the largest death toll outside sub- Saharan Africa.

Although still low (under 1%), the percentages of female sex workers living with HIV have increased in Afghanistan, Indonesia and Pakistan, as HIV transmission in these countries expands among and beyond people who inject drugs. Many people who inject drugs also buy or sell sex, thus compounding the risk of HIV transmission.

But there is also increasing evidence that intensive HIV prevention programmes among female sex workers can be highly effective. A prevention programme in Karnataka (India) was associated with a drop in HIV prevalence from 25% to 13% among female sex workers in three selected districts between 2004 and 2009 and from 1.4% to 0.8% among young antenatal clinic attendees between 2004 and 2008 in 18 districts.

In Mumbai and Thane, a similar programme was accompanied by a decline in HIV prevalence from 45% in 2004 to 13% in 2010 among brothel-based sex workers. Clients of sex workers make up the largest key population at higher risk in Asia: depending on the country, between 0.5% and 15% of adult men in the region are believed to buy sex.

In recent local studies, between 11% and 24% of people who inject drugs in Thailand tested HIV-positive, as did between 23% and 58% of those in various provinces in Viet Nam, more than 50% in parts of Indonesia and 23% in Rawalpindi and 52% in Mandi Bahauddin, cities in Punjab (Pakistan). Most countries in the region have been slow to introduce and expand harm reduction programmes. In such a context, the HIV prevalence tends to rise drastically, as it has in Pakistan (from 11% in 2005 to 21% in 2008).

However, evidence also indicates that harm reduction efforts are working in Asia. In Bangladesh's capital, Dhaka, harm reduction programmes have been credited with slowing the spread of HIV among people who inject drugs. Prevalence in that key population at higher risk rose from 1.4% in 2000 to 7% in 2007, but modeling suggests it could have exceeded 40% in the absence of those programmes. There are signs that the HIV epidemic is slowing down in Asia Region as depicted in the following figures.

Decline in TB mortality
Without treatment and prophylaxis, people living with HIV have a 20-30 times higher lifetime risk of developing active tuberculosis, compared with people without HIV. In 2010, people living with HIV accounted for about 13% of all new tuberculosis cases worldwide, and about 360 000 people died from HIV-related tuberculosis The number of tuberculosis deaths among people living with HIV has been declining since 2004. Close collaboration between HIV and tuberculosis programmes can accelerate this decline further to meet the global goal of halving the number of HIV-related tuberculosis deaths by 2015.

Tuberculosis care, cure and prevention should increase among people living with HIV. Less than a third of people living with HIV sought care for tuberculosis at a clinic in 2010. Halving HIV-related tuberculosis deaths requires this rate to double, together with an increase in tuberculosis cure rates from 70% to 85%, detection of at least 80% of tuberculosis cases among people living with HIV, and isoniazid preventive therapy reaching at least 30% of people living with HIV who do not have active tuberculosis.

Regular screening and testing should be offered in countries with high prevalence of HIV and tuberculosis, and more sensitive and specific diagnostic tools and algorithms should be used. An inexpensive daily dose of isoniazid significantly reduces the risk that latent tuberculosis will progress to active disease. At least 30% of people living with HIV who do not have active tuberculosis should receive isoniazid preventive therapy. Antiretroviral therapy should be initiated in a timely manner, because earlier treatment substantially reduces the odds of HIV-related tuberculosis illness and death. Meeting the global goal on halving the number of HIV related tuberculosis deaths by 2015 will also require the goal of universal access to HIV treatment to be met.

Key findings of global HIV epidemic
Globally, there were 2.7 million [2 400 000- 2 900 000] new HIV infections in 2010, including an estimated 390 000 [340 000-450 000] among children less than 15 years.

Globally, the annual number of people newly infected with HIV continues to decline. In sub-Saharan Africa, an estimated 1.9 million [1 700 000-2 100 000] people became infected in 2010. This was 16% fewer than the estimated 2.2 million [2 100 000 2 400 000] people newly infected with HIV in 2001.

The annual number of people dying from AIDS related causes worldwide is steadily decreasing from a peak of 2.2 million [2100 000-2 500 000] in 2005 to an estimated 1.8 million [1600 000-1900 000] in 2010. The number of people dying from AIDS related causes began to decline in 2005-2006 in sub Saharan Africa, South and South East Asia and the Caribbean and has continued subsequently.

In 2010, an estimated 250 000 [220 000-290 000] children less than 15 died from AIDS related causes 20% fewer than in 2005.

Not all regions and countries fit the overall trends, however. The annual number of people newly infected with HIV has risen in the Middle East and North Africa from 43 000 [31 000-57 000] in 2001 to 59 000 [40 000-73 000] in 2010. After slowing drastically in the early 2000, the incidence of HIV infection in Eastern Europe and Central Asia has been accelerating again since 2008.

The trends in AIDS related deaths also differ. In Eastern Europe and Central Asia, the number of people dying from AIDS related causes increased more than 10 fold between 2001 and 2010 (from about 7800[6000-11000] to 90 000 [74 000-110 000]. In the same period, the number of people dying from AIDS related caused increases by 60% in the Middle East and North Africa (from 22000 [9700-38000] to 35 000 [25 000-42 000] and more than double in East Asia (from 24 000 [16 000-45 000] to 56 000 [40 000- 76 000]).

Introducing antiretroviral therapy has averted 2.5 million deaths in low and middle income countries globally since 1995. Sub Saharan Africa accounts for the vast majority of the averted deaths about 1.8 million.

Providing antiretroviral prophylaxis to pregnant women living with HIV has prevented more than 350 000 children from acquiring HIV infection since 1995. Eighty-six percent of the children who avoided infection live in sub-Saharan Africa, the region with the highest prevalence of HIV infection among women of reproductive age.

The Indian scenario
India is one of the largest countries in southern Asia. Geographically it is the seventh largest and second most populous nation in the world. Its estimated total population in 2010 was 1,192,000,000 (RNTCP report, 2011) with over half a billion in the 15-49 year-old age group. India shares land borders with Bangladesh, Bhutan, China, Nepal, and Pakistan. The shift of population from rural to urban areas is slower in India than in most developing countries, but one-fourth of the total population is in urban areas.

Status of HIV/AIDS
HIV epidemic in India is concentrated in Most at Risk Populations (MARPs). The HIV prevalence among the High Risk Groups, i.e., Female Sex Workers, Injecting Drug Users, Men who have Sex with Men and Transgenders is about 20 times higher than the general population. Based on HIV Sentinel Surveillance 2008-09, it is estimated that India has an adult prevalence of 0.31 percent with 23.9 lakh people infected with HIV, of which, 39 percent are female and 3.5 percent are children. The estimates highlight an overall reduction in adult HIV prevalence, HIV incidence (new infections) as well as AIDS related mortality in India.

One of the key characteristics of the recent round of estimations is that it allowed for generating estimates of the HIV incidence (number of new HIV infections per year). Analysis of epidemic projections revealed that the number of new annual HIV infections has declined by more than 50 percent during the last decade. It is estimated that India had approximately 1.2 lakh new HIV infections in 2009, as against 2.7 lakh in 2000. This is one of the most important evidence on the impact of the various interventions under NACP and scaled-up prevention strategies.

Adult HIV prevalence and declining trends of adult HIV prevalence
The estimated adult HIV prevalence in India was 0.32 percent (0.26% - 0.41%) in 2008 and 0.31 percent (0.25% - 0.39%) in 2009. The adult prevalence was 0.26 percent among women and 0.38 percent among men in 2008, and 0.25 percent among women and 0.36 percent among men in 2009.

The adult HIV prevalence at national level has continued its steady decline from estimated level of 0.41 percent in 2000 through 0.36 percent in 2006 to 0.31 percent in 2009. All the high prevalence states show a clear declining trend in adult HIV prevalence. HIV has declined notably in Tamil Nadu to reach 0.33 percent in 2009. A clear decline is also evident in HIV prevalence among the young population (15-24 yrs) at national level, both among men and women. Stable to declining trends in HIV prevalence among the young population (15-24 yrs) are also noted in most of the states. However, rising trends are noted in some states including Odisha, Assam, Chandigarh, Kerala, Jharkhand and Meghalaya.

People Living with HIVjAIDS (PLHA)
The total number of people living with HIV/AIDS (PLHA) in India is estimated at 23.9 lakh (19.3 - 30.4 lakh) in 2009. Children under 15 yrs account for 3.5 percent of all infections, while 83 percent are the in age group 15-49 years. Of all HIV infections, 39 percent (9.3 lakhs) are among women. The four high prevalence states of South India (Andhra Pradesh-5 lakhs, Maharashtra^l.2 lakhs, Karnataka-2.5 lakhs, Tamil Nadu-1.5 lakhs) account for 55 percent of all HIV infections in the country. West Bengal, Gujarat, Bihar and Uttar Pradesh are estimated to have more than one lakh PLHA each and together account for another 22 percent of HIV infections in India.

AIDS related deaths
It is estimated that about 1.72 lakh people died of AIDS related causes in 2009 in India. Wider access to ART has resulted in a decline of the number of people dying due to AIDS related causes. The trend of annual AIDS deaths is showing a steady decline since the roll out of free ART programme in India in 2004.

Routes of transmission
Based on Programme data, unprotected sex (87.4% heterosexual and 1.3% homosexual) is the major route of HIV transmission, followed by transmission from Parent to Child (5.4%) and use of infected blood and blood products (1.0%). While Injecting Drug Use is the predominant route of transmission in north eastern states, it accounts for 1.6 percent of HIV infections.

Integrated counseling and testing centre
Integrated Counseling and Testing Centre (ICTC) is a place where a person is counseled and tested for HIV on his/her own volition (Client Initiated) or as advised by a health service provider (Provider Initiated). People who are found HIV-negative are supported with information and counseling to reduce risks and remain HIV-negative. People, who are found HIV-positive, are provided psychosocial support and linked to treatment and care.

There are several contexts for providing HIV testing services; voluntary counseling and testing, prevention of parent to child transmission, screening of TB patients and diagnostic testing among symptomatic patients. In the year 2010-11, guidelines have been issued for ICTC Laboratory Technicians to conduct Syphilis Screening of the clients referred by STI Clinics to ensure comprehensive testing services under one roof.

Mobile ICTCs
Mobile ICTCs are one way of taking a package of health services into the community. A mobile ICTC consists of a van with a room to conduct a general examination and counseling, and a space for the collection and processing of blood samples. A team of paramedical health-care providers (a health educator/ANM, Counselor and Lab Technician) can set up this temporary clinic with flexible working hours in hard-to-reach areas, where services are provided ranging from regular health check-up, syndromic treatment for STI/Reproductive Tract Infection (RTI) and other minor ailments, antenatal care, immunization, as well as HIV counseling and testing services. Mobile ICTCs can, thus, cater to a larger audience and be a more effective preventive intervention by ensuring the reach of services.

In addition to 5,233 stand alone ICTCs, 1,632 Facility Integrated ICTCs, 668 Public Private Partnership model ICTCs and 84 Mobile ICTCs are currently functional.

HIV-TB collaborative activities
TB being, a major public health problem, in India accounts for 20-25 percent of deaths among PLHA. It is also noted that nationally about five percent TB patients registered under RNTCP also have HIV infection. This HIV positivity among TB patients varies across the states and districts in the country between one and 13%, and is related to HIV prevalence in the general population. As prevalence of TB infection in India is more than 40%, a large proportion of PLHA also is likely to be already infected with TB bacteria. Moreover, it is known that HIV makes an individual more prone to acquire TB infection as well as progress rapidly to TB disease.

The country is dealing effectively with HIV burden, TB associated HIV epidemic is posing an important challenge. This becomes even more critical in the presence of MDRTB/ X-DR TB in the community. The existence of HIV and TB together, greatly amplifies harmful effects of each other at individual level and contribute substantially to mortality among PLHIV.

Therefore, HIV-TB programme level collaboration is a key strategy adopted by the Department of AIDS Control and Central TB division. The Department takes the lead in strengthening this coordination between the National AIDS Control Programme (NACP) and the Revised National TB Control Programme (RNTCP) at all levels.

Strategy of the NACP-III
NACP-III has placed the highest priority on preventive efforts. At the same time, it seeks to integrate prevention with care, support and treatment through a four pronged strategy:

• Preventing new infections in high risk groups and general population through saturation of coverage of high risk groups with targeted interventions and scaled up interventions in the general population;
• Providing greater care, support and treatment to larger number of PLHA;
• Strengthening the infrastructure, systems and human resources in prevention, care, support and treatment programmes at the district, state and national levels;
• Strengthening the nationwide Strategic Information Management System.

HIV/AIDS situation in  SAARC region
HIV epidemic in SAARC region is also a collection of diverse epidemics in countries, provinces & districts. HIV/AIDS continues to be a major public health problem in the SAARC Region. All eight Member States of the SAARC region are designated as low prevalence countries. On the basis of latest available information this region is home for an estimated number of 2.56 million HIV infected people in 2010. Table 02 shows the estimated number of PLHA in eight Member States of the SAARC Region in the year 2010. Three countries, namely India, Nepal and Pakistan account for majority of the regional burden.

The overall adult HIV prevalence in SAARC region remains below 1%. However, there are important variations existing between countries. Bangladesh, India, Nepal and Pakistan have reported concentrated epidemics among most at risk populations. Of the estimated number of PLHA in SAARC region, 2.39 million were living in India alone in 2010.

The first HIV/AIDS infected persons were diagnosed in 1986 in India and Pakistan. By 1993, all SAARC Member States had reported the existence of HIV infection in their countries. The cumulative numbers of reported HIV/AIDS infected persons by Member States of the SAARC Region at the end of the year 2010 are given in Table 03.

Sexual Transmission drives the HIV epidemic throughout most parts of India, accounting for nearly 90% of prevalence nationwide. The brothel based sex workers are more likely than home based sex workers to be infected with HIV and the risk is also more for currently unmarried sex workers in India. HIV transmission during injecting drug use is the primary mode of transmission in north-eastern parts of the country.

HIV epidemic in India is highly heterogeneous and appears to be stable or diminishing in some parts of the country while growing in others. HIV epidemic of Nepal is concentrated among most at risk populations and diverse in various regions/zones and districts.

HIV epidemic in Pakistan is a concentrated epidemic among IDUs and Hijra sex workers. IDU group is the core group which drives HIV epidemic in Pakistan and having the highest prevalence of 20.8%. The HIV prevalence among female sex workers in Pakistan is 01%. However, there is evidence of sexual networking between female sex workers and IDUs. The geographic trend of the epidemic is expanding from major urban cities and provincial capitals to smaller cities and towns.

Migration itself is not a high risk factor for HIV transmission. However, the circumstances in which migration occurs may increase vulnerability to infection. Cross-border migration of the sexual and drug-using networks along the India-Nepal border appears to be contributing to a two-way flow of HIV. Migrants are considerably more likely than non-migrants to delay seeking medical treatment for infectious diseases due to various factors which are held responsible for exclusion of them from basic health services in the settings to which they have migrated.

Women account for a significant proportion of people living with HIV in SAARC region. A large proportion of women appear to have acquired the virus from regular partners who acquired HIV infection during paid sex. In the region as a whole, HIV prevalence is low among general population, however, significantly higher among Most at Risk Populations [MARPs]. The low prevalence of HIV among the general population poses a significant threat as it undermines the gravity of the situation. When the infection gets established in the bridging groups such as clients of sex workers through them, HIV may spread to the low risk groups in the general population such as housewives at an exponential pace. As a result, generalized epidemics may arise in many parts of the region unless the responsible authorities take the timely decisions for implementation of appropriate timely prevention approaches to contain the HIV in the region. All the Member States have high levels of high risk factors to fuel the HIV epidemic further and faster. The identified prevailing high risk factors in the SAARC region are:

• Low level of literacy
• Poverty
• Rapid and unplanned urbanization
• Low status of women
• Discrimination and stigmatization
• High prevalence of Sexually Transmitted Infections High rates of internal and international migration
• Trafficking of women and children
• Low level of health care seeking behavior
• Social marginalization of population groups
• Low levels of condom use
• Unsafe injection practices in formal and informal health care settings Porous borders between some countries Growing numbers of Most At Risk Populations
• Civil war situations creating a huge group of internally displaced people

These identified risk factors create favorable conditions for the spread of virus across the SAARC region. In order to implement an effective prevention package for the region of SAARC, the diversity is to be considered. The factors responsible for diversity should be identified and addressed during designing as well as implementation phase.

The wide disparity between the estimated numbers of people living with HIV/AIDS and reported numbers of people living with HIV/AIDS is to be considered by both regional authorities responsible for the HIV prevention and care as well as by the National AIDS Control Programmes in prioritizing, designing and implementation of activities in HIV prevention and care continuum.