Emerging and Ebbing Threats

“Just like people in California await the next big earthquake, we in the infectious disease field are waiting for the next influenza outbreak,” says UCSF professor of medicine and infectious disease specialist Peter Chin-Hong, MD.

Influenza, commonly known as the flu, is a viral infection of the human respiratory tract. Seasonal virus strains spread around the world annually, doing minimal harm to the average healthy adult. But a few times a century, a new strain jumps to humans from another animal species, such as chickens or pigs, and can trigger a pandemic.

Such cross-species outbreaks are especially contagious and deadly because they can introduce traits against which humans have no defense. Previous flu pandemics have resulted in millions of deaths worldwide. But there’s reason to think we may be able to thwart the next one, says Charles Chiu, MD, PhD, director of the UCSF Center for Next-Gen Precision Diagnostics. Here are a couple of promising approaches:

Improving Surveillance

Vigilant, real-time surveillance and reporting are today’s best hope for stopping an influenza outbreak, Chiu says. His team uses rapid DNA sequencing to identify and diagnose cross-species diseases in remote regions of the world in order to understand, track, and – hopefully – prevent another pandemic. 

Pursuing a Universal Vaccine

Seasonal flu vaccines are ineffective against an influenza pandemic. But a vaccine that can fight off any flu – even novel, cross-species strains – might be within reach, Chiu says. “If a universal vaccine becomes available,” he says, “mass global vaccination efforts could nearly or completely control influenza by 2050, just as was done for poliovirus more than 50 years ago.”

HIV/AIDS

An HIV diagnosis in the 1980s was effectively a death sentence. The virus had hit San Francisco hard, and UCSF clinicians endeavored to care for its many victims. But their drive to overcome HIV/AIDS helped transform the disease from fatal to merely chronic. Research at UCSF spurred the development of antiretroviral therapies, and later, PrEP (pre-exposure prophylaxis), a preventive pill.

“We have the tools to stop the epidemic,” says Paul Volberding, MD, director of UCSF’s AIDS Research Institute and the Weiss Memorial Professor. But eradication by mid-century is unlikely, he predicts. Besides the sheer magnitude of the problem (about 40 million people currently live with HIV), stigma presents a formidable hurdle. “We will make a lot of progress,” he says, “but we still have much work to do on the societal and behavioral issues that perpetuate HIV.”

Tuberculosis

For a curable disease, tuberculosis (TB) still cuts an astonishing swath of destruction across the globe. The U.S. and most other developed countries have wrestled TB mostly into submission through concerted treatment, education, and prevention measures. But countries plagued with overcrowding, poor hygiene, lack of fresh water, and inadequate public health care systems have struggled to contain the pandemic.

A TB vaccine has been available since 1921, but it is not very effective. “We’ve known for a long time that a better vaccine that can prevent infection and progression to disease in those already infected will have the biggest epidemiologic impact,” says Payam Nahid, MD, MPH, a TB expert and professor of medicine. A recent candidate has shown unprecedented promise, stirring excitement among TB scientists. Meanwhile, researchers are working to improve treatments and diagnostic tests. With this confluence of advances, “the sky’s the limit for improving TB outcomes by 2050,” he says, except for one major stumbling block: “The funding is nowhere near where it needs to be.”