Call it bad luck, a medical mystery, or simply some sort of convoluted destiny, but just as the world inched closer towards an HIV vaccine, researchers have identified a new disease with Aids-like symptoms.
The discovery is unlike anything the medical field has seen before, says Dr Sarah Browne of the US National Institute of Allergy and Infectious Diseases, and who led a team of scientists in identifying the new condition.
“What we know is that this is not HIV, is not transmitted from one person to the other, but weakens the body’s capacity to fight infections just like HIV does,” Dr Browne told DN2 from the US in an e-mail conversation last week.
Researchers are puzzled by one large study in Thailand and Taiwan, where adults at the age of around 50 were found to have little immunity against infections. These people did not have HIV and their CD4 (a group of white blood cells that gives the body immunity against infections) counts were normal.
The team has named the disease Adult-Onset Immunodeficiency, which has also been found in Americans of Asian descent. It has not yet been confirmed whether the new disease has spread to Africa, but researchers do not rule out that possibility.
“We know there are many others out there, including many cases mistaken for tuberculosis in some countries,” Dr Browne had told CBS in an earlier interview, pointing to a likelihood of a misdiagnosis that could help the disease spread undetected.
That the condition was found in people aged about 50, Dr Browne explains, indicates that the condition is not acquired at birth but later in life.
The team also explained that the Aids-like symptoms were not confined within family groups, suggesting that this was not a hereditary problem.
Because it is not inherited, doctors have ruled out the idea that a single gene could be responsible for the condition.
A normal body produces chemical signals that tell it when to start fighting germs or other infections.
However, in people with this new condition, the body produces another substance that switches off this disease-fighting capacity.
This is exactly what happens in HIV, even though there is an absence of such a virus in the new discovery, which also does not affect the body’s white cells (CD4).
Researchers are not sure why the condition is developing, but they know that people suffering from it are vulnerable to a multiple of other infections such as pneumonia, tuberculosis, and fungal infections.
The condition, according to a study published last week in the New England Journal, was first discovered in 2004 in Asia. The team later enrolled 204 HIV-negative people for a six-month study. The participants had various opportunistic infections.
Among other things, the investigators examined participants’ blood for the chemical which tells the body to start fighting an infection, but in a significant number of participants they found their bodies to be making a protein which blocked this signal.
Most of the people (88 per cent) who had a certain bacterium closely related to tuberculosis and/or even other infections were found to be producing this signal-blocking chemical.
Cautious not to cause a panic, Dr Browne emphasises that this condition is not passed from one person to the other and, unlike HIV, is not caused by a virus.
While HIV attacks and destroys T-cells — the body’s main defence system against germs — the new condition does not affect these cells but fails to give the order to fight the intruders.
When this chemical signal is blocked, the body fails to fight viruses, fungal infections, and other bacteria, just as happens in an Aids patient.
This is like a police commander who fails to order his juniors to return fire against criminals firing at his team. In such a situation, the policemen (T-cells) would stand by as the robbers loot and plunder property (the body).
Describing one case last week, the Associated Press told of a 62-year-old woman from Vietnam who works and lives in the US. In 2009, she sought medical help for consistent attacks of fever and other infections.
She visited Vietnam several times in the course of these attacks and in between medication. Her doctor first thought she was suffering from tuberculosis but later realised that she had a different kind of infection that had wasted away her body from 41 kilogrammes to 31 kilogrammes.
The woman was referred to specialists at the US National Institute of Health (NIH) who, AP says, had been tracking similar cases. The woman has spent more than a year at the facility as doctors closely monitor her progress.
A statement released by the journal ProMed last week indicated that doctors at NIH, where the Vietnamese woman is admitted, are trying a variety of treatments on the new disease, including a cancer drug that stops the production of some harmful chemicals in the body.
They say antibiotics have not been found to be effective and that this new disease has the hallmarks of becoming a life-long condition.
“The fact that almost all the identified cases so far have been Asian or Asian-born people living elsewhere suggests that genetic factors and something in the environment such as infection may trigger the disease,” says the statement.
In her communication with DN2, Dr Browne said the condition was new and had no relationship with another once called ICL (Idiopathic CD4 lymphopenia, or non-HIV Aids).
ICL is a rare syndrome defined by low levels of CD4 cells in a person having no HIV. People with this syndrome are also vulnerable to opportunistic infections.
“Our patients have normal CD4 counts and a different explanation for their low immunity,” explained Dr Browne, adding that such patients produce chemicals that block a protein called interferon-gamma, which is critical for normal immune function. “This is the most likely explanation for their increased susceptibility to infection.”
Despite new threat, medics remain optimistic of HIV breakthrough
EVEN AS the new disease threatens to dampen the spirits of medical researchers, there is still optimism as a combination of old and new tricks dares the world to think of an Aids-free future.
The latest such development is a new pill that combines four medicines and will only be taken once a day, replacing the need to take multiple drugs daily and improving adherence.
The drug, Stribild by Glead Sciences, has already been approved in the US, hot on the heels of the first approval for a drug said to protect users from HIV infection.
The World Health Organisation is developing guidelines which, for the first time, will allow the use of a daily pill to prevent HIV infection.
These prescription drugs, Tenofovir and Truvada, are available in the country for use as anti-retrovirals in combination with others, but not as drugs medically called Pre-exposure Prophylaxis or PreP.
Studies carried out in Kenya, South Africa, Tanzania, Uganda, and elsewhere showed that taking a daily dose of Tenofovir or Truvada significantly protected one from HIV infection.
WHO is considering that such a preventive drug would remain under strong regulation and should first be targeted at high risk groups such as commercial sex workers, homosexuals, drug injectors, and prisoners.
Gilead Sciences have said they are prepared to work with the Global Fund and the WHO to make the drugs available to poor countries at a discounted price.
These conclusions we arrived at following two studies carried out in Kenya and Uganda and released last year.
“This is a major breakthrough, especially for discordant couples, and even for women with wandering partners who refuse to use condoms,” one of the study researchers, Dr Nelly Mugo of Kenyatta National Hospital, told DN2.
Dr Mugo described this as an incredible achievement. “It is excellent news. It simply means taking a once-a-day pill reduces the risk of acquiring HIV infection.”
The study, carried out among 4,758 HIV discordant couples — where one partner is HIV positive — was done by KNH, Kenya Medical Research Institute, Moi Teaching and Referral Hospital, and the University of Washington, US.
It proved that the two antiretrovirals, which are already in use in Kenya for management of HIV among infected people, can reduce the risk of HIV infection by up to 73 per cent.
In Kenya, the studies were carried out at KNH, Thika, Kisumu, and Eldoret. “This could fundamentally change how HIV prevention is done in Africa,” said Dr Mugo.
Home testing the new frontier in Aids war
IN EARLY July this year, the first HIV home testing kit was approved. Until then, testing had been done all over the world almost exclusively in medical settings. The saliva test provides a result in 20 to 40 minutes from a quick swab of the upper and lower gums in the mouth.
Kenya has just completed a pilot trial on the acceptability of HIV home testing among health workers. The study, led by medical consultant William M Muraah, concludes that 85 per cent of workers who took the kit home tested themselves and concluded that this should be made more accessible to all health workers.
“Approximately nine out of 10 health workers who attended an information session on the kit took the test with them after the session, and of those who took the test kits, the majority tested themselves,” says Dr Muraah.
In a new approach in the management of HIV called Treatment for Prevention, the World Health Organisation has issued new guidelines which, among others, recommend that married HIV-positive people whose partners are not infected be put on antiretrovirals irrespective of their viral loads.
The world body is working on what it says is strong scientific evidence supporting the fact that antiretroviral therapy, by lowering a person’s viral load and restoring the immune system, significantly reduces HIV transmission and TB.
Based on this, the government plans to put all people infected with HIV on medication regardless of their CD4 count after evaluating an ongoing pilot study.
This would mean that about 1.6 million people in Kenya living with HIV would be put on the programme, which would almost triple the current number of patients on this medication. Currently, 540,000 people are on antiretroviral treatment in the country.
Director of Public Health Shahnaz Sharif says the roll-out of medication to all HIV patients will begin after the completion of a test study to confirm the positive effects of beginning ARVs in the early stages of infection.
“We hope to move to a situation where all those infected will be able to enrol for the ARVs because there are indications that there are benefits that come with the ‘strategic use’ of HIV medicines that could help end transmission,” says Dr Sharif.
Other prevention measures include male circumcision, safe sex practices, and, of course, abstinence.