In the summer of 2000, public health experts and activists convened in Durban, South Africa for the 13th International AIDS Conference. Although South Africa was home to the world’s largest HIV positive population, most of the infected were far too poor to afford the anti-retroviral therapy that can transform HIV into a manageable chronic illness.

By that point, the impact of the disease seemed undeniable: With 25 percent of South Africa’s national population infected and 600 deaths each day, South Africa’s AIDS epidemic had already decimated communities. Yet because the disease remained a death sentence primarily for South Africa’s poor, its fearful name was rarely spoken. And for those brave enough to break the silence that exacerbated misunderstanding and perpetuated inaction, the price could be dear. In late 1998, a woman named Gugu Dlamini publicly announced that she was HIV-positive on radio and television stations; soon after, she was stoned to death by her own neighbors.

But by the time of the International AIDS Conference in 2000, thousands of South Africans were no longer willing to accept the paralyzing silence. Huge crowds filled the streets of Durban demanding that the public, their government, and the nations of the developed world open their eyes to the gruesome toll that the pandemic was taking. Besides the sheer number of people rallying for change, the most striking thing about these demonstrators was the T-shirts they wore, which read “HIV POSITIVE” in bold, purple lettering.

At first sight, these shirts were shocking and even discomforting, and they still are. Is the wearer, you wonder, living with the virus? If so, why would he or she want to broadcast this painful truth to complete strangers? If not, what could possibly be the impetus to draw attention in such a way? Does he or she purport to understand experiences that he or she cannot fathom living?

In fact, the T-shirt compels us to ponder why, 25 years after the disease was first publicized and 11 years after the discovery of life-saving treatment, millions the world over still bear the burden of infection alone and without hope. It forces us to consider how the global response to one of the greatest crises of our time has remained so tepid that each year the pandemic continues to claim five million new infections and three million more lives.

The “HIV POSITIVE” T-shirt, then, is an intentionally provocative rebuke to inaction. It battles the silence, apathy, and stigma that impede awareness, prevention, and treatment measures. Today, it is an internationally recognized symbol worn by people who are HIV-positive and HIV-negative alike, including renowned figures such as Nelson Mandela. In a bold display of solidarity, the wearer proclaims the need for each of us to act “positively” to fight the pandemic regardless of our HIV status.

Yet from here on campus, what it means to act “positively” to fight a global scourge is not immediately obvious. For most undergraduates at the College, the gravity of the HIV/AIDS pandemic is not in question; instead, we wonder if it is possible to make a meaningful contribution as students. After all, most of the 40 million infected reside not in Cambridge, but in sub-Saharan Africa, Asia, and the Caribbean. To compound the feeling of helplessness, we see ourselves as only undergraduates, not yet equipped with the tools of physicians or policymakers.

But in fact, Harvard is one of the best places for undergraduates interested in AIDS and other global health challenges. Here, cutting-edge research labs race to develop effective vaccines; student groups engage in political advocacy to increase political will among our elected officials; and non-governmental organizations that work in some of the world’s hardest-hit regions hire undergraduate summer interns and graduating seniors. The answer to the once-vexing question, “What can I do?” becomes clear quickly enough if you know where to look.

This week, each of us has the opportunity to take “positive” action against HIV/AIDS. Over the next few days, you may spot classmates and friends wearing an “HIV POSITIVE” shirt as part of a fundraising and awareness effort titled “Step it Up.” We wear these shirts for the same reason as our compatriots in South Africa: We feel positive about our ability to make a tangible impact in the fight against the pandemic. We realize, in the words of Dr. Martin Luther King, Jr., “the fierce urgency of now.” We can turn the tide against HIV/AIDS if and when we are all truly united against it.

Bryan C. Barnhill II ’08 is a social studies concentrator in Pforzheimer House. He is president of the Harvard Black men’s Forum. Luke M. Messac ’08 is a social studies concentrator in Mather House. He is a member of the Harvard AIDS Coalition. Tanuj Parikh ’09 is a government concentrator in Pforzheimer House. He is the chair of the South Asian Men’s Collective.