About seventy thousand years ago our species, Homo sapiens sapiens, left Africa to colonize the world but coming with us on our journey was Mycobacterium tuberculosis or TB; we have lived and evolved with TB for as long as we have been on this earth (1) and have developed an uneasy relationship with the pathogen.

TB can be fatal. At the end of the 19th century TB was the single biggest killer of people in Europe and remains one of the greatest causes of mortality worldwide. But TB persists because we have developed a degree of immunity which enables TB to remain in a latent state in otherwise healthy people for decades before it is passed on and there are populations in the Western Cape where close to everyone aged 20 years or more has a latent TB infection. So the eradication of TB is difficult. Incidence rates even in quite badly affected populations may only be of the order of a few hundred cases per hundred thousand people per year; to find one case you may need to test a thousand people. And detecting active TB is still difficult. Using microscopes we can look for bacteria in a sputum sample. We can grow the bacteria in culture and then test for resistance. Molecular tests are becoming more widely available but we still do not have a simple, cheap, point-of-care test for TB disease. To make matters worse, treatment requires at least six months and even then a cure is not certain. In South Africa the risk of TB is increased even further. The millions of migrant men who worked on the mines are very likely to have silicosis by breathing in the silica in the dust when they dig and drill for gold which increases their risk of developing TB. The migrant labour in our region then ensures that the infection will spread. To add to that, South Africa has the worst epidemic of HIV in world and being HIV-positive further increases a person’s risk of developing TB.

Controlling and eliminating TB is never going to be easy and this issue of the SACEMA Quarterly is devoted to some of the recent developments that have been made in our attempts to manage TB. Alex Welte, Elisabetta Walters and Robert Gie discuss some of the reasons that make the diagnosis of TB so difficult using the old, established diagnostic tools. They consider the potential of the new molecular test, gene-Xpert, which offers great promise but still faces significant problems and they discuss the further problem of knowing when a person is truly cured.

Cari van Schalkwyk and Mareli Claassen consider the critical problem of improving case finding for TB. Given the low prevalence and incidence of TB one needs to be strategic in the search strategies. Traditionally various signs and symptoms that are suggestive of TB have been used including persistent cough, sudden weight loss, night sweats and so on, but many people who have these symptoms might well ignore them until it is too late. Van Schalkwyk and Claassen stress the need for developing much more efficient case finding techniques and suggest ways in which this might be done.

Florian Marx and Grant Theron continue the discussion and focus on four main categories of interventions. First, enhancing TB case finding in people who have not yet accessed health care and secondly in people who are actively seeking health care. The third strategy involves active TB case finding in high-risk groups and then with a focus on anyone who is infected with HIV. Finally, they discuss the critical need to develop and implement better TB diagnostic tests and algorithms.

People infected with HIV are at much greater risk of developing TB than people who are not. Between 1995 and 2004 the epidemic of HIV in South Africa led to an increase in the incidence of TB from 100 to 500 cases per 100 000 (100k) people per year. Fortunately, anti-retroviral therapy (ART) for HIV also reduces the risk of developing TB by about 60% and this has bought the rate down to about 250 cases per 100k people per year. Elizabeth Corbett was the first to show that the dramatic rise in incidence has not been matched with a rise in prevalence because people with HIV who are not on ART will either die from TB or seek treatment much earlier in the course of their infection. This means that the epidemic of TB in HIV-positive people does not significantly affect the epidemic in HIV-negative people. Brian Williams uses this to show how the joint epidemics of HIV and TB can most easily be modelled. While the challenge of managing TB in HIV-negative people remains is is unaffected by the epidemic in HIV-positive people, and to manage TB in HIV-positive people it is of the greatest importance to start ART as soon as possible after infection with HIV.

Health-related research tends to look at single issues at a time, due to the complexities of what is involved. Indeed, formal scientific experimental investigations tend to rely on comparing situations where differences are to some extend directly controlled, or at least known. Especially when the differences are small in number – possibly one key factor only, such as a choice of treatment – the comparisons can lead to insights into the direct effects of the relevant factors.

Having said that, it is clearly impossible to investigate, in such a manner, every detail of life, or even a slightly narrower aspect like ‘healthcare’ – by examining each choice and evaluating its role in a ‘total package’ of ‘lifestyle’, ‘care’ or ‘policy’. So, is discussion about the bigger picture to be based on political machinations underpinned by naked narrow self-interest? Or is it ultimately a matter of faith or at least shared ‘values’? Or is there in fact something resembling a scientific thread that can be maintained throughout discourse?

The current edition of the SACEMA Quarterly features several pieces grappling explicitly with this challenge of understanding a bigger picture than any particular ‘scientific investigation’ can formally take on.

The theme of treating HIV with lifelong antiretroviral therapy (ART) has featured many times in these pages, and is unfortunately not one that is likely to become irrelevant and uninteresting any time soon, given how deep in the HIV hole much of Africa and other regions find themselves. Brian Williams and Reuben Granich take stock of current ambitions to ‘end’ the HIV/AIDS epidemic, reflecting on some key historical milestones and recent trends – with both of which they are very familiar. In short, we appear to be at a crucial juncture where real lasting success may be reachable, or great opportunities may be created by much effort and investment. On a closely related thread, in a separate short piece, Nathan Geffen reviews the tortuous path to consensus on the current view that anyone diagnosed with HIV should be offered immediate ART.

Matthew Chersich et al. take one step further back from the specifics of HIV management, to consider the role of sexually transmitted infections (STIs) more generally, in the context of the international framework of the ‘Sustainable Development Goals’ (SDCs). They note that health per se features explicitly in fewer of the SDGs than of their predecessor framework, the ‘Millennium Development Goals’ (MDGs), but that the overall structure of the new framework is deliberately less compartmental, and intended to foster holistic approaches to raising a tide that floats all boats. A short item by SACEMA colleague Cari van Schalkwyk sheds light on the association between the burden of HIV and human papillomavirus (HPV), two heavy hitting STIs, by using a model that includes sexual-network factors, something that is difficult to look at in observational studies.

A particular angle on the question of disentangling HIV and related ills is showcased by Simon Rigby, who reviews progress in understanding the role of ‘Intimate Partner Violence’ (IPV) in the transmission of HIV. He reviews recent attempts to model the interactions of the various behavioural factors that lead to transmission, and finds that there is no convincing case that IPV ‘directly’ contributes to elevation of transmission, although it is almost certainly associated with a total context of high risk in which some (mainly women) find themselves. Be that as it may, he concludes by reminding us that relevance to HIV epidemiology should not be the litmus test for whether a social ill is accorded importance and attracts serious attempts to address it.

In a similar vein, Roxy Beauclair considers the discourse around ‘age-disparate’ relationships – i.e. sexual relationships between people of significantly different age. Crudely put, there has been much debate about the role of ‘sugar-daddies’ in exposing young women to unreasonable risk of acquiring HIV from older men, but indeed, the formal evidence is mixed, and the interpretation is not uncontroversial. Her take away messages are about the importance of nuance and context, the need to broaden the debate to encompass all aspects of the empowerment of women, and a call not to neglect opportunities to reduce acquisition risk amongst men.

Finally, stepping furthest back and showing us the broadest view in this issue, is George Lueddeke, outlining the One Health Education Task Force (OHETF) and his forthcoming book (entitled Survival: One Health, One Planet, One Future). He offers potent reminders that most of the big challenges we current face are interlinked, and that unless a more fundamentally caring paradigm underpins key decisions about development in general, it will be difficult to make much progress on any particular goal. The process behind the sustainable development goals seems to embrace this point, but it is still far from clear whether actual developments will automatically be driven by such a broad view, given the inevitably grubby details of particular lines of evidence, varying priorities, and political constraints.

We hope you enjoy these thoughtful pieces and that they take your own engagement with the issues up a notch or two.

The concept of Open Science is that scientific discovery must be open to the scientific community and society as a whole, in the sense that anybody who so wishes, can interrogate how the scientific data were collected and analysed, and how the results of the analyses were presented and contextualised. In academic circles, this overarching aim has been translated into the four pillars of open science: 1. open data, 2. open code, 3. open access (i.e. open papers) and 4. open evaluation (i.e. open peer review)) (1). However, the focus of most Open Science initiatives has been on making data, code and scientific papers freely available. Comparatively less attention has gone to ensuring that these scientific products are also comprehensible and digestible for experts and non-experts alike.

Open communication, the practice of communicating science via freely accessible media to a diverse audience, has always been at the heart of the SACEMA Quarterly. Ever since the first issue of the magazine, in March 2009, the aim of the Quarterly has been to provide regular updates, articles, and reviews of developments in the world of quantitative epidemiology – with particular reference to challenges and solutions relevant for South Africa. The intention of the magazine was always to present work that is typically highly technical in nature, in a way that makes it accessible to interested health professionals and policy-makers.

Still, over the years, we realised that many other interest groups not part of in this initial target audience also had a strong desire to access and understand epidemiological modelling and analysis work. These include not-for-profit organisations, funders and programme implementers in the health space, as well as funders and programme implementers in the area of science, technology and innovation. In addition, there is a growing recognition that for science is to serve society optimally, more and better quality communication is needed between scientists and the general public.

After careful consideration of the evolving Science Communication landscape in South Africa and globally, we concluded that maintaining our own online magazine was no longer the most efficient way of reaching a large, general audience. Instead, we have decided to partner with The Conversation to bring articles from SACEMA researchers to a wider audience, both within South Africa and abroad. We believe this change will allow us to spend more time and effort on writing high-quality articles for a general audience, while sparing us the time and effort that goes into soliciting andWhile saddened at the realisation that this issue will be the SACEMA Quarterly’s last, we are thankful for your interest in our work through the years, and trust that we will count you among the readership of future SACEMA-led articles in The Conversation. reviewing articles.

Leveraging the role of open communication in science is not only about publishing science communication articles efficiently, however. It is also about integrating continuous input and feedback from the communities in which the research takes place, and who are affected by its findings. Open communication means making a concerted effort to listen to the questions that the community has, and allowing the design of models and analyses to be guided and informed by voices from the relevant communities. It involves finding out which channels and modes of communication (e.g. social media, drama, mass events, newspaper articles, cartoons or slots on radio talk shows) are most suitable for the audience and the purpose of the communication. Importantly, open communication is not effortless nor free. It requires dedicated training, and there is a zero-sum game between time invested in open communication and time invested in the actual research and the production of peer-reviewed, scientific journal articles. Therefore, funders and academic institutions should provide appropriate budget lines to match the explicit expectations from researchers to become good open communicators and dedicate a fraction of their time to open communication. Furthermore, the process of evaluating and rating scientists should include measurable, relevant benchmarks of their efforts and successes in open science communication and knowledge transfer to society.

While saddened at the realisation that this issue will be the SACEMA Quarterly’s last, we are thankful for your interest in our work through the years, and trust that we will count you among the readership of future SACEMA-led articles in The Conversation.