“Can someone give me a good reason why all TB suspects should not have access to drug susceptibility testing (DST)? I want a good reason to stop me from doing what we think we ought to do,” Dr Ken Castro, Director of the Division of Tuberculosis Elimination at the Centers for Disease Control and Prevention (CDC) told an audience at the 37th Union World Conference on Lung Health, held from October 31st to November 4th in Paris.

Over the course of the conference, Dr Castro argued passionately for an emergency scale-up of laboratories in resource-limited settings in order to respond to the threat of extensively drug resistant TB — which could cause the death of millions of people with HIV in Africa (and possibly the world) and undermine the recent progress in tackling HIV/AIDS (see more below).

“There is an urgent need for enlarged budget plan for lab capacity — buildings, hardware, software and all the components,” Dr Castro said.

The stance won him praise from treatment activists like Mark Harrington of the Treatment Activist Group. “[Dr Castro]’s turned into the biggest proponent of universal access to culture and DST and universal treatment for all,” said Harrington. In fact, when he sensed a less than enthusiastic response to Dr Castro’s appeal from TB community in the audience, Harrington urged them all to become “activists like Ken Castro.”

But if the response from other TB experts at the meeting had seemed muted, it wasn’t because they disagreed with the call for universal access to improved diagnostics — it was because they know that introducing the laboratory capacity to do mycobacterial culturing and DST (or possibly even the new emerging TB diagnostic technologies) into resource constrained settings will truly be a daunting challenge.

“Setting up culture facilities requires a particular investment of resources and expertise, and [Medecins sans Frontieres’] field experience has shown that this is often more complicated and difficult to realize in the field than is widely appreciated,” says a just released MSF report on the current TB diagnostic pipeline (which can be downloaded at http://www.accessmed-msf.org/documents/Diagnostics%20Pipeline%20Report.pdf).

“It’s been said over and over that laboratory services really represents the weak link in the chain of TB control. This weakness is now accentuated within the context of XDR-TB,” said Dr Karin Weyer, the Director of Unit for Tuberculosis Operational and Policy Research at the South African Medical Research Council (MRC), and who is also with the WHO/International Union Against Tuberculosis and Lung Disease’s (IUATLD) Supranational Reference Laboratory in South Africa.

Dr Weyer presented an overview at the conference on the challenges involved in scaling up laboratory networks, what will be needed for DST and an overview of rapid diagnostics that are currently in the pipeline.

The current state of TB diagnostics in high burden countries

But, first, a look at what sort of laboratory services are currently available for people with TB in the resource limited settings that have the highest burden of TB (and often HIV as well):

No point-of-care test at the primary health care level

Most people at risk of TB live in areas with little access to quality laboratory services. The best place to diagnose them would clearly be when they first present at the health post/primary care level, but so far there are no simple point-of-care “dipstick”-like tests available (although some, such as the LAM urine test, are being developed). But for the time being, suspected cases of TB are can only be assessed clinically at this level and then referred for diagnosis by smear microscopy at a facility with access to a peripheral laboratory. 

Smear microscopy at peripheral laboratories

Conditions at these peripheral laboratories can vary dramatically. The MSF report describes the peripheral laboratory setting as potentially having:

• Only basic laboratory facilities (in other words, no equipment such as a working centrifuge or biosafety hood that should be standard in most modern laboratory settings): usually just a single room, often lacking electricity and water, understaffed, and performing only sputum smear microscopy
• Widely variable levels of staff training and quality control
• No facilities for culture-based tests (except in a very few urban labs that may have rudimentary facilities for solid culture, and limited training)
• Little capacity to handle high workloads — each laboratory technician can only process a limited number of slides each day
• Sometimes no laboratory staff at all — with the lab just used for sputum collection with testing done at central laboratory

But what’s worse is that smear microcopy performed in these laboratories just isn’t very good at recognising TB. On average, smear microscopy detects less than half of the cases with TB (Dye); and when someone also has HIV the sensitivity can fall to as low as 20%, according to a recent report from the Foundation for Innovative New Diagnostics (FIND) and WHO’s Special Programme for Research and Training in Tropical Diseases (TDR)  - see http://www.who.int/tdr/publications/publications/pdf/tbdi/tbdi.pdf

The poor sensitivity of smear microscopy in people with HIV has been a primary impetus behind the search for new diagnostic technologies.

Culture at the district hospital or reference laboratory

The inadequacy of smear microscopy also has led HIV activists to call for universal access to culture for any person with HIV suspected of having TB. In fact, in the opening address at last year’s Union World Conference, Zachie Achmat of the Treatment Action Campaign (TAC) had called for universal access to bacteriological culture - see http://www.aidsmap.com/cms1037490.asp

Culture, where it is available, is much more sensitive than smear microscopy, yielding a diagnosis in most TB cases; and it can be used for drug susceptibility testing. Even so, the TB diagnosis is significantly delayed since growing mycobacteria in culture takes time, usually between two to six weeks  (although new methods such as rapid liquid culture and microscopic-observation drug-susceptibility (MODS) shorten this period considerably).

Culturing is also considerably more expensive than smear microscopy, and requires specialized equipment, highly trained personnel as well as a reliable supply of water and electricity. Thus, culturing is typically only performed at the district hospital or reference laboratory — and, as the MSF report notes, “the same conditions described for a peripheral laboratory may be encountered in poorly supported district hospitals or in urban areas.”

In her talk at the Union World Conference, Dr Weyer stressed that the current laboratory services system often lacks adequate infrastructure, frequently has inadequate or outdated equipment, poor biosafety measures, and a scarcity of human resources and financial resources. One point that came up repeatedly during the conference was that there is little local capacity in most of Africa to service biosafety hoods or other laboratory equipment — with technicians sometimes having to be flown in from South Africa to keep laboratories running smoothly.

So what this really means is that there are a severely limited number of facilities that can integrate culturing into patient management in any meaningful way.

According to Dr Paul Nunn, coordinator of the TB/HIV and Drug Resistance unit of WHO’s Stop TB Department, outside of South Africa, there are just 13 laboratories in all of Africa that can truly perform culture and only eleven of these laboratories can do DST. (South Africa has 16 labs capable of performing culture and fourteen capable of doing DST).

As a result, the FIND/TDR report says that “the use of culture in the public sector is generally restricted to smear-negative TB and to cases of suspected drug resistance” (subsequent treatment failure). And given the capacity constraints, the current infrastructure can’t even keep up with the MDR-TB cases. According to a FIND press release, “of the 22 countries with the highest burden of TB (accounting for 85% of the global caseload), fewer than half have more than three laboratories in the entire national laboratory network with the capacity to do drug susceptibility testing (DST).

According to Dr Weyer, only about 5% of the MDR-TB cases that occur are diagnosed as such.

But TB can be rapidly fatal, so, as Achmat pointed out at last year’s conference, people with HIV and smear-negative TB often have little time to be processed through a diagnostic algorithm. Culturing, or some improved method for diagnosis, is needed for routine patient management — as soon as a person with HIV and a suspected case of TB presents to the clinic.

Empiric Treatment

But some of the TB experts at last year’s meeting were sceptical about the suggestion — saying, for all the reasons discussed above, that it would be impossible to scale-up the capacity to provide universal culturing in Africa. Furthermore, there might be an easier way to manage people with HIV and smear negative TB. As per the recent WHO recommendations for the diagnosis of smear negative TB in people with or suspected of having HIV, (see http://www.who.int/entity/tb/publications/2006/tbhiv_recommendations.pdf) anyone who is seriously ill (with danger signs) should immediately be treated with a broad spectrum antibiotic (though not a fluoroquinolone because those drugs could delay TB diagnosis), and possibly PCP treatment, at a higher level health facility if possible. During this time, all available lab tests (including an HIV test if necessary) should be conducted. If the patient is indeed HIV-positive and there is no clinical improvement on the antibiotics within 3 to 5 days, he or she should be put on tuberculosis treatment.

If followed faithfully, this algorithm should save many lives. There is only one problem: It won’t work for MDR or XDR-TB.

The threat of MDR- and XDR-TB

With each passing day, the news regarding the XDR-TB outbreak in South Africa seems to grow worse. A few days ago, the Health Department reported that 303 cases of XDR-TB have now been identified nationwide, (see http://www.int.iol.co.za/index.php?set_id=1&click_id=125&art_id=qw1164315604818B243). While according to November 12^th’s South Africa’s Sunday Tribune, 267 new cases of XDR-TB have been detected in KwaZulu Natal — (and no, these numbers don’t seem to really add up). (see http://www.sundaytribune.co.za/index.php?fArticleId=3532602).

The article attributes some of the new cases to a “softening” of the definition of XDR-TB— however, the definition was changed only to make it more reproducible across laboratories since second line DST is not standardised; and the revised definition is actually more clinically useful since it is more consistently associated with a poor prognosis (see http://www.aidsmap.com/en/news/618C4802-2F77-4BEF-982D-A9A53B032298.asp).

A survey to determine the precise contribution of XDR-TB to the TB caseload in KwaZulu Natal is only just getting under way. It is unclear when exactly a similar nationwide survey to determine the prevalence of XDR-TB will be conducted— or who exactly will be in charge of it, the MRC or the Health Department.

But even though the burden and geographical dispersion of the XDR-TB outbreak in Southern Africa still needs to be delineated, there are indications that it has probably already spread to most of South Africa’s immediate neighbours. At least ten cases have been found in the Northwest Province of South Africa, and given that province’s cultural ties to neighbouring Botswana, it seems likely that it has crossed that border. It has been detected in at least one individual from Lesotho. And at the conference, caregivers from Namibia told this reporter that they have seen a dramatic increase in the past twelve months over the previous one-year period in treatment failures and mortality in their patients with TB. They suspected that this could be due to XDR-TB, but they had only just sent specimens off to the Supranational Reference Laboratory in South Africa for DST.

Meanwhile, as early as May of this year, documented cases of XDR-TB had occurred independently in at least 17 countries across the globe — demonstrating that XDR-TB is not an isolated phenomenon.

“Inadequate treatment of MDR-TB will, predictably, result in the emergence of TB strains with resistance to second line drugs,” Dr Sarita Shah of the Albert Einstein College of Medicine in New York told an audience at the world conference. Indeed, several TB experts expressed the conviction that XDR-TB is the inevitable result of the global failure to provide timely diagnosis and adequately treat people with MDR-TB — although some saw it more as a failure of TB programmes while others attributed the blame to the inadequacy of the tools (diagnostic techniques and drugs) used to manage TB.

How MDR can easily become XDR: A case in Abkhazia

Dr Francis Varaine, the TB Coordinator for MSF, described a number of cases from a project in Abkhazia in the Caucasus where treatment-adherent patients with MDR-TB went on to develop XDR-TB. Patients in the programme have cultures sent out to Rome or Antwerp for DST, and depending upon their drug resistance profile, they are given a regimen of at least five active drugs (with the assistance of the WHO Green Light Committee which helps procure drugs for approved DOTS plus programmes).

For example, one patient, Alexei, was resistant to streptomycin, isoniazid and rifampicin at baseline. He was put on an appropriate MDR TB treatment with five effective drugs, and after four months his culture became negative and remained so for at about a year.

“So of course Alexei and the whole medical team thought he was going to be cured,” said Dr Varaine. But after 13 months, he became culture positive again and was now resistant to the fluoroquinolone class of drugs. The medical team thought the TB could be due to reinfection, and started with a new regimen with additional drugs. For the next ten months, his culture went back and forth between being positive and negative. Then the culture became permanently positive and had developed resistance to a number of the drugs he was on; in other words, it was XDR-TB. Finally he was declared a treatment failure; treatment was stopped and he died three months later.

Afterwards, DNA fingerprinting of the TB cultures showed that Alexei was not reinfected but that he continued to be infected with the same strain of TB even after he became culture negative. The strain just acquired more resistance over time. And lest the audience conclude that this was due to a failure to continue taking the medications, Dr Variane said;

“Alexei was very compliant. As he was homeless, he was kept in the hospital even during the continuation phase and the treatment was really given under strict duty. And during the treatment, he suffered from nausea and vomiting, depression, insomnia, and skin discoloration due to clofazamine.”

“Patients like Alexei are not uncommon in our projects. Indeed, if XDR TB is quite rare at admission in our projects…[at about 1%-4%] about 10% of our patients develop XDR TB at one stage during the follow up,” Dr Varaine continued.

And this was is a model programme. In most programmes, negative outcomes in patients with MDR-TB range from 30 to 40%. Even in the US, a recent study reported treatment success rates of only 57% (Narita).

“This should not be a surprise because we all know that the MDR TB treatment we have is weak… and the MDR TB treatment we have is also toxic. In at least one third of the patients, at least one drug has to be removed from the regimen because of serious side effects,” said Dr Variane. 

It should also be pointed out that the second-line TB drugs are expensive — MDR-TB cost up to 100 times more to treat.

Dr Variane described several other troubling cases in which XDR-TB developed and one where it was transmitted within a family before it could be diagnosed.

“We have a delayed diagnosis [up to three months for DST in some cases] that's leading to delayed initiation of adequate treatment and makes adequate infection control almost impossible…So, my message from the field is that we definitely cannot survive with the current tools that we have.”

The MSF experience would seem to have stark implications for XDR in Africa. Even if the global “emergency response” is able to contain the current XDR-TB outbreak in South Africa, which seems unlikely, the problem could re-emerge there at anytime because underlying the XDR-TB outbreak is a firmly established epidemic of MDR-TB. 41%of the culture positive cases (221 out of 544 cases) were MDR-TB in the KZN survey that identified the first 53 cases of XDR-TB.

Meanwhile, even though the lack of access to second-line drugs (other than the fluoroquinolones) makes the evolution of XDR-TB in the rest of Africa more difficult — for thousands of people with HIV who develop active MDR-TB, when there is no adequate treatment, death is just as likely.

Globally, the burden of MDR-TB is almost half a million new cases a year, although 62% of these cases are in Russia, China and India (Zignol). MDR-TB is becoming more common in sub-Saharan Africa as well. For example, in one study from Kampala, Uganda, almost 10% of the TB patients screened had MDR-TB (Worodria), and during a discussion session one specialist from Uganda said that the prevalence there has been increasing recently. In Kenya, meanwhile data from 2002, suggested that less than 1% (8 total) of about 1022 cases sent to the UK for DST were MDR (Githui) but within the past nine months, 48 new MDR cases have been identified in the slums around Nairobi alone (see http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/11/10/wtb10.xml )

As Dr Weyer said, because of the lack of DST capacity, 95% of MDR-TB cases go undiagnosed so these cases are probably just the tip of the iceberg.

Dr Kevin de Cock, Director of the WHO Department of HIV/AIDS believes that MDR-TB is probably on the increase wherever people with HIV are living longer due to antiretroviral treatment — because people with HIV still tend to be at greater risk of TB even on ART. But because of the lack of laboratory capacity, he believes most of these cases fail to be recognised; noting that: “If the KwaZulu Natal outbreak had happened anywhere else in Africa, it would probably have gone unnoticed.”

“We cannot make progress on this issue of drug resistant TB without labs,” said Dr de Cock.

Since it is impossible to effectively treat an unrecognised case of MDR- or XDR-TB, drug-resistant TB is only likely to become more resistant and more prevalent in the population. Thus both MDR- and XDR-TB seem poised to be persistent and growing problems in countries with a high burden of coinfection and overstretched health systems.

So what can be done to control it? Without improved access to diagnostics — nothing. DST is not only required for diagnosis, it is needed in order to put together a regimen of effective drugs to cure that individual’s TB. And if this isn’t done, it means that person’s death, and — without effective infection control measures — the spread of the drug-resistant strain to the medical staff and the community. Laboratory capacity must be scaled up to improve the detection and management of both drug susceptible and resistant TB.

Plans to introduce more laboratory capacity into Africa have been in the works for some time. For example, the Global Plan to Stop TB 2006-2015 calls for an aggressive development of lab capacity.  “Expansion of laboratory services would have to be almost exponential to reach the 2015 targets and needs to happen very rapidly,” said Dr Weyer.

But the XDR-TB outbreak has provided additional impetus to development partners in the industrialized world to deliver the necessary funding and support for those targets to be met.

Still as the MSF report points out, this is easier said than done.

“Trying to scale up laboratories is complicated… and … requires much more than just transfer of modern technology,” said Dr Weyer.

Clinically useful laboratory services require a transportation system to rapidly get specimens to the lab; a reliable electrical power and water supply; a proper plan of maintenance and supply management; staff specifically trained (and retained) on DST and culture techniques, and quality assurance and control programmes would have to be implemented. Finally, there has to be a system to get the results to the healthcare team as soon as they are ready. “It doesn’t make such sense trying to accelerate the diagnosis of patients if we can’t also provide adequate treatment for these cases,” she said.

New TB diagnostics may facilitate scale-up

However the transfer of modern technologies is also part of what may make the impending TB laboratory scale-up possible — at least at the referral/district hospital level. In fact, one of the reasons why there hasn’t been greater pressure to scale up DST in resource limited settings is that the results take too long (sometimes up to 18 weeks) to be useful for patient management.

But the TB diagnostic pipeline is extremely full — and some of these technologies dramatically speed the time to confirmation of TB and detection of resistance, as well as increase throughput capacity (and thus the number of specimens that can be screened at a site).

“New tools are coming. The diagnostics are around the corner,” said Dr Vinand Nantulya of FIND and the STOP TB Partnership Task Force on Re-tooling. He told an audience attending the Stop TB Working Group Annual Meeting on New Diagnostics that several diagnostic tests are to be introduced into national programmes at the referral/district hospital level by next year. Because of the MDR- and XDR-TB crisis, he said “there is an urgency to roll some of these tests for drug resistance into the demonstration phase a year ahead of schedule.”

The demonstration phase means that the efficacy studies have been completed. These tests have been shown to work in controlled studies, but their usefulness when integrated into a programme setting must still be demonstrated before WHO recommends their routine use in TB programmes.

These diagnostics include the Capilia TB test; Becton Dickinson’s liquid culture-based tests: the Mycobacterial Growth Indicator Tube-TB (MGIT-TB) and MGIT-DST; the FastPlaque TB-Rif (phage-based DST); and the GenoType MTBDR from Hain LifeSciences. In addition, at the conference, FIND announced that, in response to the urgency surrounding MDR- and XDR-TB, they are now exploring the feasibility of implementing the non-commercial MODS method for culturing and DST.

The Capilia TB test confirms that what is growing in a culture is TB and not some other common mycobacteria such as BCG — which may be important when using only culture for DST since some other mycobacteria are not susceptible to TB drugs. However, other rapid molecular-based tests (see below) may be necessary to differentiate between TB and other mycobacteria that can infect people with HIV (Richter).

The MGIT system is a culturing system that has already been approved for use in industrialised countries for years. The MGIT-TB and DST tests can culture TB within as little as seven days (though it can take longer, and up to 42 days to be certain of a negative result). Once cultured, MGIT-DST can take another eight to twelve days to detect first-line TB drug resistance, and there is growing clinical experience using it for second-line drug resistance (O’Brien). 

The automated system can process 960 samples at a time, but requires an extremely expensive machine (which according to the recent MSF report costs Euro 40,000 and up to Euro 100,000 in Africa). How much assistance FIND and or development partners are going to provide resource-limited countries to install this system is unclear, however, in light of the international response to the XDR-TB emergency, the cost of the equipment may no longer be so much of an impediment for its introduction into high risk countries.  FIND has begun to launch demonstration projects involving about 100,000 patients in eight countries (including South Africa, Zambia, Kenya and Tanzania — although not DST, yet).

The FastPlaque TB-Rif tests use a rapid biological amplification method to culture mycobacteria within two days, and when the test includes rifampicin, it can detect resistance to that drug. The FastPlaque technique does not appear to be as sensitive as conventional culture, however, some of the negative reports on the utility of the method are related to its use at the peripheral laboratory level where contamination is more likely.

Laboratories with culturing capacity can use the test to quickly and directly detect resistance to the rifampicin, which generally goes hand in hand with resistance to isoniazid. Thus rifampicin resistance can be used as a surrogate for MDR-TB. Results from the test can be incorporated into algorithms to determine whether further DST needs to be performed on a specimen.

The MODS method is a freely useable and adaptable liquid “microcolony” detection method that recent reports (see http://www.aidsmap.com/en/news/D34B367A-8A20-4C6A-8E25-B4400168E920.asp) suggest may be even more sensitive than conventional culture, and fast — with a positive result in a median 6 or 7 days regardless of whether the specimen was smear positive or negative; and a negative result can be determined within 15 days. DST results so far seem to correlate well with results obtained with conventional methods. However, the method requires the medium to be handled frequently and there are concerns about the health risk to laboratory staff.

FIND’s involvement is a welcome development. It is hoped that with FIND’s expertise, the method will be packaged into a simpler, safer and easier to implement format which could make it possible to safely introduce into a much larger number of district level hospitals.

The GenoType MTBDR from Hain LifeSciences is a commercialised test that uses conventional PCR to amplify genes responsible for rifampicin and isoniazid resistance (and potentially others) (Østergaard Thomsen). Another GenoType line probe could also be included for speciation, or differentiating between TB and other mycobacteria. The test can provide next day results but can only be used on smear positive specimens. One plus, however, is that the mycobacteria in the specimen are killed, so this technique poses much less of a safety risk to laboratory personnel.

A similar commercialised test, the Inno-LiPA Rif TB assay from Innogenetics is not in the FIND portfolio, however, it has been extensively used in Latvia. It only tests for rifampicin resistance but again, this may be a surrogate for MDR-TB. Dr Weyer described it as potentially a point-of-care test but “unfortunately, so very expensive.”

She also noted that a recent FIND/TDR study compared the fast plaque against the Inno-LiPA test in Lima, Peru, to gold standard of conventional (but slow) indirect culture-based DST using Löwenstein-Jensen medium. “The negative predictive values of all… of these tests are really promising, meaning that we can quickly screen out MDR-TB,” she said.

PCR is of course a very specialised technology — usually with a dedicated staff with different skills than those trained to perform TB culture. PCR also must be housed separately from areas where culturing is conducted in order to prevent contamination. Thus it isn’t really clear how these tests will fit into the typical TB referral laboratory workflow.

However, according to Dr. Ruth McNerney of the London School of Hygiene and Tropical Medicine, the “reluctance to invest in the new technology has already been largely overcome in HIV/AIDS treatment programmes where tests for assessing viral load are widely available.” She believes that it may be possible to set up “a tiered network of NAT laboratories to perform testing for TB, HIV and other diseases and conditions as appropriate.”

In other words, this technology might be more easily incorporated into the HIV laboratory infrastructure that is being put in place in Africa. “It will require HIV/TB programmes to work together with other health specialties and investment from international donors,” said Dr. McNerney.

This would mean coordination and integration of TB and HIV programmes at an entirely new operational level (and in South Africa and its neighbours, this needs to be an emergency response).

MSF’s take on the diagnostic pipeline

But none of these diagnostics technologies are really the simple, safe, fast and extremely sensitive lab test that is still so desperately needed. The MSF report concludes that, for now at least, most of the existing or emerging diagnostic tests are of little practical use where they are needed most, in the peripheral laboratory settings where most suspected TB cases present for diagnosis and treatment.

And the MSF report cautions against trying to force-fit “high-tech strategies…into low tech settings” — saying that they have too many examples of how this is not an appropriate approach.

For now, the peripheral laboratories will have to make the most of smear microscopy — and try to improve how they network with the referral levels where the rapid culturing or PCR technology is supported.

Involving the HIV community and treating team in the scale up of TB laboratory capacity

So as these new diagnostic tests and laboratory capacity is integrated into resource limited settings, it is vital that the HIV treatment community get engaged to be certain that the systems and strategies that are put in place meet the needs of people with HIV and with, or at risk of TB. There has to be a paradigm shift in HIV programmes – namely that access to accurate and timely TB diagnosis (and even DST in Southern Africa) MUST be part of the basic package of care for people with HIV. 

This looks increasingly possible. The TB world is mobilising around XDR-TB. Now. And the HIV programmes must seize the opportunity before it passes.

“I think the mindset is going to have to be more like the scale-up of antiretrovirals mindset,” said Mark Harrington. “Ok, they went from zero to thousands of patients within a year. It might even be within some of the same facilities, although the infection control issues are scary.”

The HIV community in Africa must pressure their governments to request adequate assistance in scaling-up TB laboratories — while the opportunity is still there.

“We need community scrutiny of what are going to be those [laboratory] plans just like we do with HIV,” said Harrington.

The HIV community should make sure that these new initiatives contribute to, rather than detracts from HIV management capacity. The HIV community can make sure that the wheel isn’t reinvented with parallel laboratory infrastructures, and parallel specimen transfer mechanisms. For example, we have a wealth of experience in utilising “off-site lab tests,” and setting up systems such as the USAID-sponsored motorcycle couriers used for CD4 and viral load, which could be mobilised for TB as well.

As already noted, some of the TB laboratory scale up could even be piggy-backed on the HIV laboratory infrastructure — how and whether this occurs is something that the HIV community needs to be invested in to be sure that this capacity is used and expanded in the way that is most beneficial to people with HIV.

But so far, it isn’t clear how engaged the HIV community has really become with TB.

 
“I think the TB community has done a great deal to change and accommodate to the needs of HIV and yet, unfortunately, I think we still remain two communities divided by two common infections,” said Dr de Cock.

“I think the TB community still has to reach out more to the HIV community. But I also want to comment and to acknowledge I think the TB community has changed more than the HIV community has and that actually the balance, more effort needs to come from the HIV side. From the HIV perspective we have to remember that in high burden countries and high burden settings TB intervention is actually going to have to be delivered through HIV services and TB needs to be at the center of AIDS care in high burden developing countries.”

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