The HIV/AIDS epidemic threatening so many countries has not yet hit Pakistan, but the risk of transmission remains high, experts say.
Doctors and officials told IRIN that male and female sex workers, truck drivers, unscreened blood transfusions and needle sharing were the biggest dangers.
"Right now the prevalence of HIV is low, but there are a lot of risk factors which can contribute to a high prevalence rate," Syed Sharaf Ali Shah, director of the government's AIDS control programme in the southern province of Sindh, told IRIN. "It is an opportunity for us to act and prevent it now."
The official estimate of HIV/AIDS cases in Pakistan, which has a population of about 145 million, is about 2,000. However, Shah said the World Health Organisation (WHO) believed it to be as high as between 80,000 and 100,000 across the country.
He said neighbouring countries - including India and Nepal - had missed the opportunity to halt the HIV/AIDS epidemic. "Even if they make efforts now, they cannot prevent it, but in Pakistan, we still have time, so this opportunity should be utilised," Shah emphasised.
Shah's programme is at the forefront of the government's efforts to prevent an epidemic of the deadly disease, but most doctors and nongovernmental organisations (NGOs) working in the sector believe that its spread is inevitable.
"AIDS is very much under-reported. If they say prevalence is limited, it does not mean that we should relax about it. In our country the prerequisites are there for an explosion," Saleem Azam, a medical doctor and the president of the Pakistan Society - an NGO working with drug addicts and AIDS - told IRIN.
Shah said very little blood was screened before transfusion across Pakistan. In Sindh alone there was a need for up to 35,000 units of blood each month, and only 20 percent of it was being screened. "Seventy percent of the total blood is used in seven to eight major hospitals, which means if you fix these centres, 80 percent of your blood will be screened," he said.
Shah said screening was important to ensure that blood was free of hepatitis B and C, both sexually transmitted infections (STDs), and HIV/AIDS.
Another potential catalyst to the spread of HIV was the large number of drug users sharing needles, Azam said. "Injecting drug users were first discovered in Karachi. Seventy percent of them share needles, so the HIV threat is much bigger here than in other areas of the country."
Most of Karachi's population of about 14 million people live in extremely squalid conditions. Although no official estimates exist on the number of drug users in the sprawling metropolis, Azam said there were several thousand people sharing needles. According to the United Nations Drug Control Programme (UNDCP), almost half a million people in Pakistan are drug addicts.
"Different studies have found different rates of HIV prevalence in drug users. In one study of 100 people, only one case was reported. In another study, only two cases were discovered, but in our own centre we did not find a single case," Shah said.
Shah is also running a pilot project on HIV/AIDS prevention in the poor Essa Nagri district of Karachi with the help of the Joint United Nations Programme on HIV/AIDS and the UNDCP.
"This is Sindh's first drop-in centre for street addicts. We raise awareness and work here to prevent blood-related infections like HIV/AIDS," he said. They also carry out a needle exchange programme.
Another major source of concern for doctors and officials trying to fight HIV/AIDS are commercial sex workers and truck drivers. Both groups are considered to be particularly high-risk in that they could spread the virus widely and quickly.
Richard Harrison, a coordinator for Greenstar Social Marketing, told IRIN that although there were no reported cases of HIV/AIDS among the two groups so far, there were several cases of other STDs.
"We are concerned because they have a very serious risk of spreading such diseases. In other words, it is a very dry wood out there, and a match could light a very big fire," he said. Greenstar Social Marketing is a non-profit organisation which provides poor Pakistanis with cheaper medical care.
Male and female sex workers operate illegally in Pakistan, where is it banned, so they are not compelled to take regular heath examinations.
"I go home every six months, but last year I went just once," said Tariq Khan, a truck driver in the Moripur Truck Station of Karachi, one of the biggest truck stops in Asia. He told IRIN that he had had sex with a commercial sex worker once, but that he was careful and used a condom.
Shah said a high incidence of syphilis - an ulcerating STD, which showed that AIDS could easily spread in the group - was found in truck drivers and prostitutes.
"We found 12 percent syphilis, which is very high, and it is a marker for the HIV infection," Shah said. "Looking at the behaviour, more than 70 percent of the truckers admitted having commercial sex," he added.
He noted that only five percent said they used condoms. "Ninety percent did not use condoms at all, and even the five percent said they do not always use condoms."
Shah was referring to patients checked at one of the health clinics jointly run by the truckers' association, Greenstar Social Marketing, NGOs and Sindh's provincial government. "Many gave a history of anal sex or homosexuality, and their knowledge of sexually transmitted diseases was very low," he said.
An estimated 20,000 truck drivers and their assistants pass through Moripur every day, transporting oil or other goods all over Pakistan. Tariq Khan, a resident of a frontier town near Islamabad, is married with three children and earns US $84 a month.
"Yes, I have heard of AIDS. It is a punishment from God for our sins," he told IRIN, adding that he would not be "tempted again by the devil", and would avoid sex workers.
Shah said the core group - male and female sex workers - were considered to be the main source of infection, and truckers the link between them and the population in general. "They can catch the infection and go home and infect their wives, and they in turn will bear children with the HIV infection," he explained.
"The indications are that it [HIV] has not established itself in our commercial sex workers. That is why there are so few reported cases in Pakistan. But once that happens it will be very difficult to control it, and it will also be too late," he warned.
HIV/AIDS was first reported in Pakistan in 1986 in a migrant worker who had returned from the Middle East to his home town in the North West Frontier Province (NWFP). Its spread has remained limited, but Shah said the situation could dramatically change. "There are about three million Pakistanis working abroad, and our first infection came from them, to their families, and their children."
Harrison said no models had been prepared to see how many people in Pakistan were at risk of being infected by the virus.
Aid workers, at any rate, say more health clinics and awareness campaigns are needed across Pakistan. Harrison said his group, supported, among others, by the United States, Germany and Britain's Department for International Development, was providing subsidised condoms to prevent the spread of STDs. It was also planning new health centres, primarily for HIV/AIDS prevention.
"We are focusing on getting people to use condoms to protect against disease," said Harrison about his organisation, which has been providing family planning services for about 10 years.
Adrian McGee, project coordinator for a German-assisted NGO, Orphans Refugees and Aid International, told IRIN that his organisation had been working with the truck drivers since 1998, making them aware about AIDS and other STDs.
"We talk about their [drivers'] sexual activities," he said from Peshawar, the capital of the NWFP. "They have little knowledge about HIV, and we tell them about it by starting a conversation and chatting at the tea-stalls or benches where they are sitting," he said, adding that they also distributed leaflets.
Whereas most of the truck and bus drivers were "receptive" to their message, there were a few people who were uncomfortable with such candid discussions of sex and sexual matters, and their impact on health, McGee added. This could in part be due to traditional norms in this strict Islamic society of Pakistan, where discussion of sex is taboo. But "usually they are very interested to know more about it", he added.
Harrison said he favoured a soft approach towards increasing people's awareness of such a deadly disease. "We cannot scare people away. We have tried that in other countries, and it did not work," Harrison said. "However, we can tell them that if you are going to indulge in such activities, at least be safe."