Surveillance for Emerging Infectious Diseases: A Global Partnership

Of the many lessons that have emerged from the COVID-19 pandemic, the biggest is the importance of constant surveillance for new infectious diseases throughout the world. Capacity for that surveillance has grown through collaboration between government, academic, and private institutions to identify potential new pathogens and develop strategies to contain and treat them. In a recent Diagnostics Dialogues podcast, Quest experts Hema Kapoor, MD, and Robert Jones, DO, discussed how the global surveillance community responded to COVID-19, and what the future of infectious disease surveillance holds. Dr. Kapoor is senior medical director, Infectious Disease and Immunology and the leader of the Quest Global Diagnostic Network. Dr. Jones is the medical director, Research and Development, Infectious Disease and Immunology, and associate medical director, Quest Diagnostics Nichols Institute.

As tragic as the COVID-19 pandemic has been, the response to it, from a scientific and public health point of view, has been rapid and successful. “If we compare COVID-19 to the 1918 influenza epidemic,” Dr. Kapoor said, “it is clear we have come a long way.” In the 1918 epidemic, 500 million people became infected worldwide, at least 10% of whom died. While the number of infections is larger for COVID-19, the fatality rate is closer to 1%.

“We have much better tools today,” Dr. Kapoor said, with the ability to rapidly isolate and sequence the virus, and to use that to rationally develop vaccines based on the key structural elements of the virus.

But significant challenges remain, owing to the genetic nature of the SARS-CoV-2 virus. Its genetic material is RNA, Dr. Jones explained, without significant quality control during replication, meaning it accumulates mutations faster than a DNA virus would. This is one reason that the hopes for “herd immunity” in the general population were frustrated, since neither infection nor vaccination completely protects against reinfection.

“This is the third time since 2013 that a coronavirus has jumped from animals to people, so it shouldn’t be a surprise that it can happen again,” Dr. Jones noted. “This is why global surveillance is so important.”

Quest has led the development of the Global Diagnostic Network, an alliance of 9 commercial laboratories that collectively serve two-thirds of the world’s population. Members meet regularly to share insights about potential emerging diseases. Deidentified test results can be combined with data from government and other sources to determine key characteristics of emerging pathogens.

“We see reports coming in every day,” Dr. Kapoor explained. Expertise is needed to separate the signal from the noise. Some viruses emerge seasonally, then die out again as the weather changes. A virus that shows up in multiple regions in a short period may be of concern, especially if the genotype is very similar or identical between regions, as this suggests rapid spread from a concentrated source. “We need to keep our ears to the ground to differentiate between the smaller and the bigger problems,” she said. 

“Sometimes an infection will be driven by spread within a certain subpopulation,” Dr. Jones said. For the moment, that is true of monkeypox, which is spreading largely through close and intimate contact. “I don't think any of us expect the spread of monkeypox to be anywhere near the size of COVID-19, but at the same time, it's a significant illness,” with a longer period of potential spread.

But the infectious disease community is on the case, he added. “Most of us are a little geeky, in terms of being fascinated by new diseases. I would guarantee you that 90% or more of infectious disease doctors, once monkeypox hit the news, were already reading up on it, well in advance of ever seeing a case.”