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HIV & Blood Safety

Unpaid, voluntary blood donors are essential

One of the primary routes of HIV transmission is through direct contact between your blood and HIV-infected blood. Although the majority of HIV infections via blood occur among people who inject drugs (PWID), medical settings still account for a significant number of new HIV infections. Across the world numerous cases of HIV transmission through blood transfusions, medical injections, medical waste and occupational exposure, are both reported and unreported.

There are an estimated 250,000 new infections per year as a result of the reuse of needles and syringes, 1 and in Africa 250 to 500 people are newly infected with HIV each day as a result of unsafe blood transfusions. 2 3Testing of blood is essential but remains absent in many low and middle-income countries.

Blood: Donations, transfusions and HIV

Blood transfusions are essential treatment for excessive blood loss and for diseases such as haemophilia. If a person receives a blood transfusion with HIV-infected blood, there is a 95 percent risk they will become infected with the virus. 4However the chance of acquiring HIV from a blood transfusion varies between countries depending on the level of blood screening and other safety precautions in place. There is a notable difference between high- and low-income countries; in the UK, the risk is extremely low at 1 in 6.5 million. 5

The first tests for HIV in donor blood were not implemented in countries until 1985, four years after the first case of AIDS was reported. Between 1985 and 1992, France and Romania had the highest number of AIDS diagnosis as a result of HIV infection through blood transfusion, and more than 8,000 people in the US were believed to have acquired HIV from blood transfusions during this period. 6

"HIV infection continues to be a risk associated with blood transfusions"

Haemophilia is a disease characterised by the deficiency of blood clotting factors in the blood. 7 This condition is treated through the frequent transfusion of blood products such as plasma, which contain platelets, and clotting factors, such as factor VIII. 8 Thousands of haemophiliacs contracted HIV through receiving these life saving blood products during the late 1970s and 1980s, a time when blood was pooled to extract the factor VIII and not screened or treated for HIV. 9 Plasma is a blood product which can be heat treated and since heat treatment was implemented in 1985, plasma is now completely safe where this method is used. 10

The World Health Organisation (WHO) outlines a number of recommendations which countries should follow to maintain a safe and constant blood supply. These steps prevent transfusion-transmissible infections (TTI), which include HIV-1, HIV-2, hepatitis B, hepatitis C and syphilis, passing from a blood donor to the recipient of a blood transfusion. 11 According to the recommendations countries need:

  • A nationally coordinated blood transfusion service
  • Voluntary unpaid donors
  • To test all donated blood
  • To use blood efficiently and appropriately
  • To ensure a safe transfusion practice
  • To have a quality systems check throughout the blood transfusion process.

The roll-out of widespread safety measures such as donor screening and selection guidelines makes the risk of HIV transmission today virtually non-existent in high-income countries. 12 However, despite more lower-income countries implementing these strategies and guidelines since 2004, HIV infection continues to be a risk associated with blood transfusions in many parts of the world.

  • 25 countries do not currently screen all donations for HIV, Hepatitis B & C and syphilis. 13

HIV and blood donors: Who can donate?

A key aspect of ensuring a safe blood supply is the screening and counselling of donors to limit the number of people infected with HIV from donating.

Voluntary, non-remunerated blood donors are those who donate on their own accord without coercion or incentives, such as money. In some countries, such as the UK, 100 percent of donations come from voluntary, non-remunerated donors. The recommendation by WHO to only use this type of donor was first made in 1975 in the form of the World Health Assembly resolution 28.72. 14 These donors are sought after because they are more likely to be donating for altruistic reasons rather than for any personal gain. 15 Injecting drug users are more at risk of HIV infection and often need money to fund their drug habit. If donating blood is seen as a source of income, high-risk individuals that would otherwise not donate, may do so and therefore risk the safety of blood supplies.

When an individual needs a donation and a family member steps forward to donate blood they are referred to as a 'family/replacement' donor. However, like paid donors, this type of donor often leads to higher number of HIV-infected blood donations. In many countries paid donors and family blood donors continue to make up a large percentage of blood donations. 16 For example, 70 percent of donations in Pakistan are from 'family and replacement' donors with a further 10 percent of donations from paid donors. 17 The risk posed by these donors is illustrated by 2008 figures, which show that 6.8 percent of PWID in Pakistan admit to selling blood in return for money and in some provinces HIV prevalence in blood donations is more than 5 percent. 18

The process of donor screening involves asking a series of questions about the donors' lifestyle to ensure individuals who may be infected with HIV do not donate blood. By evaluating whether a blood donor participates in risky behaviour, the risk of them unknowingly donating HIV-infected blood can be determined. 19 20

The most recent reported case in the US of HIV being transmitted through transfusion occurred in 2008. 21 This followed a six year period whereby there were no reported HIV transmissions through transfusion. HIV transmission occurred in this case, firstly because the routine donor (and therefore often considered the safest type of donor) answered incorrectly to questions about high-risk behaviour during the donor screening questionnaire. Secondly, due to being recently infected the donor was in the window period (can be up to 12 weeks when tests are unlikely to detect HIV) which resulted in the infected blood being used.

The importance of donors answering honestly to eligibility questionnaires is emphasised by this case. It was highlighted by the CDC that although the risk of HIV transmission through blood transfusion is extremely unlikely in the United States, it should not be ruled out as a possible route for HIV transmission. 22

Men who have sex with men (MSM) donating blood

The ban on MSM from donating blood is currently enforced in many countries, such as France and the United States. The United States' ban was enacted in 1983 before testing of donor blood for HIV began, as more MSM were infected with HIV than other donor groups. The United States policy bans any man who has had sex with a man since 1977 (which includes single encounters) from donating for life. However, the policy for heterosexuals is markedly different. For example, a heterosexual is deferred for only 12 months if they have sex with a man who has sex with men (if you are female), an injecting drug user, or a sex worker. 23

"the ban is outdated and unscientific"

In the summer of 2013, Canada's policy changed to allow blood to be donated by men who have not have sex with men in the last five years. Previously, there was a lifetime ban on MSM donating blood. Despite this positive move, many argue that the five year deferral period is still discriminatory. 24

Banning MSM from giving blood has been a controversial issue for some time. Many argue that the ban is outdated and unscientific as many MSM are in long term relationships and practice safe sex but are banned for life, whereas heterosexuals who engage in risky behaviour are only banned for a year. 25 26 27 28 29Organisations such as the American Red Cross support a deferral rather than a lifetime ban for MSM. 30 It is believed that a donor should be evaluated on the risk they pose by the behaviour they engage in, rather than the group they fall into. 31 On these grounds it is argued that eligibility questions should be reviewed. The availability of nucleic acid tests (NAT), which reduces the window period and makes testing much more accurate, helped to support the argument for a change in the ban against MSM donating. These tests have been found to almost eliminate the possibility that HIV infected blood will pass through the testing stage, even in countries with high HIV prevalence. 32

In support of upholding the current policy, the Centre for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) identify that in the US, HIV prevalence in those MSM who are likely to donate is 15 times higher than the general population. 33 34 FDA modelling illustrates the increase in risk by introducing a deferral period for MSM, like those used for individuals such as sex workers. A 12 month deferral will result in 1,600 more HIV infected units being donated, detection of which will rely on screening. 35

Following a review in June 2010 the U.S. Advisory committee on Blood Safety and Availability decided to uphold the ban against MSM donating. They claimed that further scientific research was needed on this topic. 36 Nevertheless, in 2011, following an evidence-based review the UK government decided to lift the lifetime ban on men-who-have-sex-with-men (MSM) donating blood. 37 38However, MSM remain banned for a year following their last sexual (anal or oral) encounter, protected or unprotected. 39

How is blood tested for HIV?

The WHO promotes the formulation and implementation of a national blood policy by a country's government. 40 Initial HIV testing uses antibody tests to detect antibodies to HIV in the blood. As the virus becomes established the body makes increasing amounts of antibodies. However, it can take between 2 weeks and 3 months after initial infection before an individual produces antibodies and HIV is detectable. This gap is known as the window period and blood donations infected with HIV screened with antibody tests at this time may not be detected. 41

However, other tests exist to further reduce this window period, such as p24 antigen tests, which screen for proteins attached to the HIV infected cell and nucleic acid testing (NAT), which screen for the genetic material of HIV. 42 These tests reduce the window period down to about 12 days. It is because these 12 days remain that donor screening and counselling is still important to further reduce the chance of a person infected with HIV giving blood.

The NAT test is particularly important where prevalence is high as the number of window period donations are more likely. However, HIV prevalence is often highest in poorer countries and unfortunately NAT tests are expensive and therefore these countries usually only have antibody tests. The chance that an HIV-infected donation will not be detected is therefore greater in these countries.

In 2009 blood screened for HIV in Greater Accra, Ghana amounted to 33,294 units of blood, of which 3.68 percent was found to be HIV positive. 43 Ghana tests 100 percent of its blood donations, however this is done using only antibody tests. Therefore the window period remains a significant interval, which suggests some units may continue to pass through screening undetected.

In October 2005, South Africa introduced NAT testing and as a result there were no cases of HIV transmission by blood transfusion reported to the haemovigilance programme, a transfusion surveillance system. 44 45

Do all countries test for HIV?

Each year, 107 million units of blood are donated, half in high-income and half in low- and middle-income countries. 46 In 2013, WHO reported that 25 countries lacked the resources to screen for transfusion-transmissible infections (TTIs), meaning 24 percent of blood donations in low-income countries are not screened. 47 Worryingly it is often countries with a high HIV prevalence that have inadequate screening programmes in place. For example, although the HIV epidemic in Tanzania is generalised (HIV prevalence is 5.7 percent), blood screening is extremely limited, with only 35.7 percent tested in 2007. 48 

The situation in China during the early years of the epidemic highlights the need not only for voluntary, non-remunerated donors but also safe procedures for blood collection, testing and transfusion. 49 Farmers from Henan province donated blood during the 1990s to collection sites where, to save money, the donors blood was pooled, the plasma extracted and then the remaining blood injected back into the donor. 50 51 More than 100,000 farmers were infected with HIV in this way and unknowingly continued to donate infected blood, which was passed on through blood transfusions.

In 2012, around 270 children tested positive for HIV after being infected in hospitals in Kyrgyzstan during the past decade. Untested blood transfusions, and the use of contaminated medical equipment caused these HIV transmissions, reflecting the urgent need to follow universal precautions in healthcare settings. 52

Blood shortages and HIV 

Around 1 percent of the population need to donate blood(or 10 donations per 1000 population) 53 for a country to have a sustainable blood supply. Some countries find it difficult to achieve this target, often relying on paid donors to avoid blood shortages.

Blood shortages can increase the risk of HIV transmission through blood transfusion as health authorities may become less stringent about the source of donated blood. 54 55 A lack of voluntary donors may lead to the use of paid or family replacement donors who may be more likely to be living with HIV (see: HIV and blood donors: Who can donate?). 

Blood donation rates (per 1000 population) vary considerably between high- and low-income countries: 56

High-income countries - 39.2 donations
Middle-income countries - 12.6 donations
Low-income countries - 4.0 donations

Globally, 75 countries collect less than 10 donations per 1000 population - the majority of these are African countries.

Sometimes cultural factors may inhibit the success of blood programmes. For example in China, cultural beliefs are often the cause of blood shortages. In traditional Chinese culture the loss of blood is not only detrimental to your health but also a disloyal act against your ancestors. 57 However, on the other hand it is also believed that receiving an unnecessary blood transfusion benefits your health and in many rural parts this practice is used as a 'health booster'. 58 59 Inappropriate clinical use of blood, such as this, not only contributes to blood shortages, but in countries which do not test blood appropriately, can increase the risk of HIV infection. 

Those most in need of safe blood and therefore most vulnerable from blood shortages and unscreened blood are pregnant women, children and haemophiliacs. 60 61 A lack of safe blood in southern Africa accounts for an estimated 15 percent of anemia related child deaths 62 63 and 44 percent of maternal deaths are due to hemorrhaging during pregnancy in sub-Saharan Africa. 64 65

Attempts globally to meet the Millennium Development Goals 4 (to reduce child mortality), 5 (Improve maternal health) and 6 (to combat HIV/AIDS, malaria and other diseases) 66 will not be achieved without persistent efforts by individual countries and the global community to develop safe and sustainable blood supplies.

The ' Global Database on Blood Safety' provides the latest blood safety statistics.

Medical injections and HIV

Medical injections are injections received as treatment, or to prevent illness (e.g. immunisation).

The Safe Injection Global Network defines a safe injection to be:

"Safe for the patient, the health worker and the environment" 67

Unsafe medical injections and HIV transmission

Unsafe procedures when administering medical injections have serious repercussions for the spread of HIV. However, despite the risks, un-sterilised needles and syringes continue to be re-used. Globally, up to 39 percent of injections are administered with equipment that has previously been used or is un-sterilised. 68

Estimates concerning the probability of becoming infected with HIV through unsafe medical injections differ markedly. Some studies claim that HIV transmission via medical injection is responsible for 20-40 percent of all new HIV infections in Sub-Saharan Africa. 69 In contrast, the WHO estimates a far more conservative 2.5 percent, emphasising that HIV transmission in healthcare settings (notably medical injections) is an area of concern, but that most infections are sexually transmitted. 70 71

The global trend over the past decade has been positive and progress is being made. In 2000, the WHO estimated that in developing countries, unsafe injections accounted for 5 percent of all new HIV infections. Since then, a number of safe injection campaigns have been launched worldwide. By 2010, the estimated number of HIV infections transmitted through unsafe injections fell by 87 percent. In fact, this dramatic progress has made the elimination of HIV transmission (as well as HBV (hepatitis B) and HCV (hepatitis C)) via this route, an achievable public health target in some regions. 72

Re-use of dirty and unsterilised needles and syringes

A number of studies have illustrated the parallel between the re-use of equipment and infection with blood borne viruses. 73 74 Once a person receives an injection a small amount of their blood can remain on the needle or syringe. If the person was infected with HIV and the same needle or syringe is used on another person, without correct sterilisation there is a risk they may be infected with HIV.

HIV infected blood on needles, syringes and other medical equipment can survive for up to two hours outside of the body 75 and it has been found that syringes containing HIV infected blood can still transmit HIV for up to 4 weeks, even after being rinsed. 76

Receiving injections in healthcare settings is very safe in developed countries. Healthcare workers in these countries have easy access to new equipment and have undertaken training in safe injection practices. By contrast, access to training, new equipment and resources to sterilise equipment is often lacking in developing countries and it is in these countries where the transmission of HIV infection in healthcare settings occurs. 77

For example in Gudamb, India, unsafe practices such as only rinsing needles between vaccinations have reportedly been carried out by rural health workers.

“For sterilisation we are supposed to carry kerosene and a cooking stove with us... but for six months there has been no kerosene supply... for me, immunising the children is a bigger priority" - Jayalakshmi Nair, a rural health worker 78

Disposable syringes can also be reused and generate large amounts of waste, which often fuels the demand for cheap injection equipment and has been associated with the transmission of HIV.

Healthcare systems must be strengthened to provide healthcare workers with training and resources in order to make medical injections safer. 79 80 Similarly, patients must be made aware that medical equipment should be new or sterilised before use.

Avoiding unsafe injecting practices

  • Auto-Disable Syringes

Technology such as single dose, pre-filled Auto-Disable (AD) injection devices (used for vaccinations) and AD syringes 81, which have a one-way valve making the syringe useless after one use, have the potential to make injections in developing countries safer. 82 83 84 Currently, AD syringes are used mainly for immunisation programmes where the potential for the reuse of injection equipment is high. A 2003 joint statement from WHO, UNICEF and UNFPA stated that AD syringes should be used for immunisations, particularly during immunising campaigns. 85 However, vaccinations only account for 10 percent of injections whereas 90 percent are for curative (or treatment) purposes. 86

Despite the phasing out of sterilisable and disposable syringes by some international organizations and governments, both continue to be used instead of AD syringes. 87 The most recent study found the percentage of non-industrialised countries using AD syringes for routine immunisation had increased since the previous study to 62 percent. However, exclusive use of AD syringes was still low at 38 percent. 88 Sterilisable syringes rely on the safe practice of the user, which can fluctuate in response to other factors. For example, sterilization may be overlooked during busy periods, such as mass vaccination campaigns, or when access to resources is limited, such as fuel to boil water.

  • Waste disposal

Waste disposal is a problem if the correct facilities are not in place (e.g. incinerators) - however AD syringes for example, cannot be collected and distributed for reuse. Access to AD devices in remote areas is also problematic. However, if governments accept the need for injection safety and AD syringes become readily available, it is likely that the disposal of and access to AD syringes will cease to be a problem - as will HIV transmission through medical injection.

Whereas the reuse of medical equipment occurs predominantly in developing countries, healthcare facilities in developed countries are still not 100 percent risk averse. In 2008, an Ambulatory Surgical Center (ASC) in Las Vegas in the United States was closed following evidence that syringes were being reused and equipment used for colonoscopies was not being cleaned between patients. 89 90 This resulted in 40,000 people requiring tests for HIV, and hepatitis C and B. 91 Following this, an inspection by the Nevada Board of Licensure and Certification found lapses of infection control in 28 of the states 51 ASCs. 92 The CDC campaign slogan "One Needle, One Syringe, Only One Time" is aimed at health workers in America to raise awareness of the importance of new equipment. 93 

Limiting the use of injections for medical purposes

In some countries the risk of HIV infection through medical injection can be limited by keeping the number of injections received to a minimum. Studies in sub-Saharan Africa indicate that individuals who receive 5 or more medical injections are 2.3 times more at risk of being infected with HIV than those who do not. 94 In Uganda, a correlation between HIV prevalence and having more than 5 medical injections was found. Of those who received 5 or more injections 10.8 percent of men and 11.4 percent of women were infected with HIV, whereas 4.0 percent of men and 6.3 percent of women, of those who had not received an injection, were infected with HIV. 95

WHO estimates that up to 70 percent of injections in some countries, were 'medically unnecessary'. 96 97 For example, in some countries injections are given unnecessarily to administer antibiotics or vitamins. 98 99 Oral medication is an alternative to injections and this treatment should be used wherever possible.

Occupational exposure and HIV

If HIV occupational health precautions are not followed healthcare workers may be at risk of HIV infection as a result of their work. Incidents of occupational exposure to HIV-infected blood are usually due to a percutaneous injury (i.e. from needles, instruments, bites which break the skin, etc.). The average risk for HIV transmission after such exposure to infected blood is low - about 3 per 1,000 injuries. Nevertheless, this is still understandably an area of considerable concern for many health care workers. 100

Certain specific factors may mean a percutaneous injury carries a higher risk, for example:

  • A deep injury
  • A high viral load in the patient (which means they will be more infectious)
  • Visible blood on the device that caused the injury
  • Injury with a needle that had been placed in a source patient's artery or vein.

If percutaneous exposure occurs then the site of exposure should be washed liberally with soap and water but without scrubbing. Bleeding should be encouraged by pressing gently around the site of the injury (but taking care not to press immediately on the injury site). It is best to do this under a running water tap.

"If intact skin is exposed to HIV infected blood then there is no risk of HIV transmission"

There are a small number of instances where HIV has been acquired through contact with non-intact skin or mucous membranes (i.e. splashes of infected blood in the eye). Research suggests that the risk of HIV infection after mucous membrane exposure is less than 1 in 1000. 101If mucocutaneous exposure occurs then the affected area should be washed thoroughly with soap and water. If the eye is affected, it should be irrigated thoroughly.

If intact skin is exposed to HIV infected blood then there is no risk of HIV transmission. 102

How many occupational infections have been reported?

Up until December 2006, health care workers in the USA reported 57 occupational HIV infections. Of these, 48 had percutaneous exposure; 5, mucocutaneous exposure; 2, both percutaneous and mucocutaneous exposure; and 2, an unknown route of exposure. In addition, 140 possible occupational transmissions have occurred among healthcare personnel. These are cases in which a worker is infected with HIV and has a history of occupational exposure, but did not have a test immediately before and after the possible exposure. As no other risk factors are reported, it is most likely that the infection has occurred as a result of that occupational exposure. 103

It should be noted that because of the voluntary nature of the reporting system, there might be some under-reporting of cases. In addition, the U.S. Centers for Disease Control and Prevention emphasise that over 90 percent of health care workers infected with HIV also have non-occupational risk factors for acquiring their infection. 104

In the UK, as of November 2008, the Health Protection Agency (HPA) has reported that there have been five documented cases of HIV infection after occupational exposure in the healthcare setting, the last being in 1999. 105

What are Universal Precautions?

Universal precautions ensure health and safety at work and are intended to protect healthcare workers, patients and the environment.

In a healthcare setting workers should take precautions with every patient to eliminate the need to make assumptions about people's lifestyles and how much of a risk they present. 106 Health care workers should have the right to be able to protect themselves against infection, whether it is HIV, Hepatitis or other TTIs.

The following universal infection control precautions are advised by the World Health Organization 107 to ensure occupational health. These help protect health care workers from blood-borne infections including HIV:

  • Hand washing after direct contact with patients.
  • Use of protective barriers such as gloves, gowns aprons, masks, goggles for direct contact with blood and other body fluids.
  • Safe collection and disposal of needles and sharps, with required puncture- and liquid- proof boxes in each patient care area.
  • Preventing two-handed recapping of needles.
  • Covering all cuts and abrasions with a waterproof dressing.
  • Promptly and carefully cleaning up spills of blood and other body fluids.
  • Using a safe system for health care waste management and disposal.

Appropriate medical waste disposal is essential to prevent used and potentially contaminated medical equipment being recycled. However, this is reliant on the necessary disposal facilities being in place. 108 Safe sharps disposal can be achieved by placing used sharps into purpose-built boxes; this prevents accidents in the workplace and the re-use of equipment. It also protects members of the public from exposure to needles, which can easily occur if medical waste is disposed of alongside normal refuse.

Post-exposure Prophylaxis

Research has shown that the use of antiretroviral drugs if given soon after an injury may reduce the risk of transmission. Such treatment is referred to as Post-exposure Prophylaxis (PEP). PEP is recommended for health care workers if they have had a significant occupational exposure to blood or another high-risk body fluid that is likely to be infected with HIV. 109

Although HIV exposure through a needlestick injury can usually be avoided by following good working practices, health care workers should consider the implications of taking PEP. This will help them to make a swift decision in the event of an accident where an injury occurs.

HIV-positive healthcare workers

There have been less than 10 reports worldwide of HIV-positive healthcare workers infecting their patients. 110 Following standard procedures, and taking antiretroviral treatment can vastly reduce the risk of HIV transmission from healthcare worker to patient. In 2013, the UK overturned a previous ban on HIV-positive healthcare workers undertaking certain medical procedures, reflecting the realisation that this type of transmission is extremely rare. 111

Medical waste and HIV

Men and women search for needles and syringes by hand, IndiaHIV-infected medical waste can be hazardous to healthcare workers and the general public if it is not disposed of safely and appropriately. If waste is not managed properly, there is an increased risk that a person will suffer an needlestick injury, potentially exposing them to HIV. This problem is most prominent in developing countries where efforts to stop medical waste being sorted and repackaged for future sale are essential.

Dhaka, Bangladesh, has particularly suffered from the lack of management for medical waste. A study in 2005 found an estimated 200 tons of waste came from Dhaka's 600 healthcare establishments per day. It found that in 60, out of 68 establishments surveyed, 22.6 percent of the daily waste was hazardous. 112 Very few establishments separated their waste into hazardous or non-hazardous waste to be disposed of separately and items such as needles, syringes, blood bags, and body parts were routinely disposed of as domestic waste.

Throughout developing countries the growing market for used needles and syringes has entrenched a process of recycling needles and syringes into communities. 113 This process involves sorting through rubbish sites to collect medical waste and is often carried out by children. These needles and syringes are then repackaged and sold. In India a batch of rinsed syringes collected in this way can be sold for up to 10 rupees or 14 pence. 114

The transmission of HIV among injecting drug users is a major route of transmission in many countries as a result of sharing needles and syringes. The need for harm reduction services such as needle and syringe exchanges prevents the sharing of equipment and limits the improper disposal of hazardous waste.


Boys collect used needles and syringes on a rubbish siteThe parallel between blood safety and HIV cannot be overlooked. This route of transmission should be the easiest to combat, especially with the development of new technologies aiding health workers to practice safely. Using a new needle and syringe every time not only saves lives but is also far more cost-effective in the long-term, when considering the life-time medical costs associated with HIV treatment and care. 115 116

Ending the use of unsafe blood and reuse of medical equipment requires an holistic approach, which should not only target healthcare workers, but also those who profit from the recycling of needles and syringes and those who profit from the collection and use of unsafe blood.

Countries who do not observe World Health Organisation recommendations must increase efforts to overcome the obstacles they face in the effort to make blood products and healthcare settings safe from HIV.



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