Infrastructure is usually what we notice when it fails. A collapsed bridge stops traffic. A power failure disrupts businesses. A broken water system can put entire communities at risk.

There is another form of infrastructure whose failure can be just as consequential, even though most people never see it: the systems that tell us when a disease threat is emerging.

Disease surveillance is often treated as a technical public health function. It should be treated as essential infrastructure.

Surveillance is the organised collection, analysis and interpretation of health information so that unusual patterns can be detected and acted upon. It connects community reports, health facilities, laboratories, epidemiologists, data systems and decision-makers.

When these parts work together, a cluster of unusual illnesses can become a signal rather than a surprise. When they do not, authorities may only recognise a threat after transmission has already expanded.

The World Health Organizationâs International Health Regulations require countries to maintain capacities to prevent, detect, assess, report and respond to public health risks. That makes surveillance more than a technical exercise. It is part of the basic architecture of health security.

Yet surveillance is rarely discussed with the same language used for roads, electricity, telecommunications or water. It is often funded as a programme, attached to a particular disease or strengthened temporarily when an emergency arrives.

That approach is backwards.

A surveillance system cannot be assembled effectively after an outbreak has started. Epidemiologists need training before they are needed. Laboratories need equipment and quality systems before specimens arrive. Data platforms need to be functional before the first unusual cluster appears. Community reporting channels need trust before people are asked to use them.

Africa CDC making progress

Africa has made important progress, but the remaining gaps show why surveillance needs to be viewed as long-term infrastructure. The Africa Centres for Disease Control and Preventionâs (Africa CDC) Health Knowledge Hub on surveillance and reporting describes disease surveillance and reporting as an important component of public health systems, while work across the continent continues to address infrastructure, workforce, governance and technology.

This is not simply a question of buying better software. A sophisticated digital platform cannot compensate for laboratories that lack capacity, health workers who are overstretched, weak reporting channels or data that cannot move between institutions.

The same principle applies to event-based surveillance. Traditional systems often depend on people presenting to health facilities and cases being formally recorded. But early warning can also come from less conventional signals: reports from communities, media monitoring, hotlines or unusual events noticed by frontline workers.

Africa CDCâs work on event-based surveillance highlights the growing role of these approaches across the continent. Their value is simple: they can help public health authorities notice something unusual before it becomes a large dataset.

Disease knows no borders

Surveillance also has to extend beyond national borders. Pathogens do not stop at immigration checkpoints, and neither should public health intelligence.

People move across African countries for trade, employment, education, tourism and in response to conflict and displacement. A disease signal detected in one country may therefore have implications for its neighbours.

The infrastructure argument becomes even stronger when we consider laboratories and genomic surveillance. Detecting a suspected outbreak is one thing. Determining what pathogen is responsible, whether it is changing and how cases may be related requires laboratory and genomic capacity.

Africa has been expanding this capacity. In November 2025, Africa CDC launched Agari, a continent-wide genomic data platform intended to enable countries to share and analyse sequencing information for faster public health decision-making. Africa CDCâs Africa Pathogen Genomics Initiative also aims to strengthen molecular diagnostics, genomic surveillance and epidemiology across the continent.

These investments are not useful only during one outbreak. As with roads or telecommunications networks, their value comes from being available before the emergency and remaining useful afterwards.

There is also a financial argument for changing how we think about surveillance. Emergency response is expensive. Once transmission has accelerated, governments may need to mobilise personnel, establish treatment centres, procure supplies, conduct mass vaccination or testing campaigns and manage wider social and economic disruption.

Early detection does not guarantee that an outbreak will be contained. But it creates something extremely valuable: time.

Time to investigate. Time to confirm. Time to communicate. Time to deploy resources. Time to protect health workers. Time to intervene before a manageable event becomes a much larger emergency.

Treating surveillance as infrastructure therefore means more than increasing a budget line. It means building systems that are sustained between emergencies.

Laboratories as national assets

Governments should invest in the public health workforce that runs surveillance. Laboratories should be maintained as permanent national assets rather than emergency facilities. Digital systems should be interoperable rather than isolated by programme or donor. Community reporting should be strengthened rather than treated as an afterthought. Cross-border mechanisms should be tested before they are needed.

It also means measuring success differently. A surveillance system should not be judged only by how many cases it reports. It should also be judged by how quickly signals are detected, investigated, shared and translated into action.

âA bridge is not considered unnecessary because it prevents people from falling into a river. A water system is not a luxury because it prevents contamination before people become ill. In the same way, surveillance should not be considered optional because it helps prevent crises that never become visible.â

The politics of prevention are difficult because success can be invisible. If surveillance detects a threat early and an outbreak never becomes a crisis, there may be no dramatic headline to demonstrate what the investment achieved.

But that is precisely the point.

A bridge is not considered unnecessary because it prevents people from falling into a river. A water system is not a luxury because it prevents contamination before people become ill. In the same way, surveillance should not be considered optional because it helps prevent crises that never become visible.

Africa does not need to wait for the next major outbreak to discover the weaknesses in its surveillance systems.

The continent already has institutions, expertise and experience to build stronger systems. What is needed is a shift in mindset: from surveillance as a project to surveillance as infrastructure; from emergency spending to sustained investment; from isolated national systems to connected regional intelligence.

The next public health threat may begin with a single unusual case, a laboratory result or a report from a community that does not yet look important.

Whether Africa notices that signal early enough will depend not only on the people watching for it, but on whether we have built the infrastructure that allows them to see it. DM