An excerpt from Disease Detectives: True Stories of NYC Outbreaks.

Dr. Westyn Branch-Elliman contributed to this chapter.

There exist within NYC, communities that feel more like a small town than a perspiring slab of metropolis. People know and speak to their neighbors, greet each other warmly on the street, and watch over each other’s children. Single- and two-family brick homes with small, manicured lawns line quiet streets. There is usually one small community hospital, the kind of place where you’d likely run into someone you know, an employee, patient, or visitor. Dr. Anthony Quinlan was a board-certified gastroenterologist in just such an enclave. He specialized in endoscopy, procedures to detect ulcers and troublesome growths in the intestinal tract and remove them before they became troublesome. In January of 2000, he moved into a brand-new, state-of-the-art gastroenterology and endoscopy center in Brooklyn, the borough where he had gone to medical school and done residency training. It was home. His practice was rapidly growing as was his family. At fifty-two years old, he was a newly blessed father. Home was hectic and work demanding, but life was good.

It was in Dr. Quinlan’s tranquil community, on a breezy day at the end of April 2001, that he was asked to consult on a patient at the hospital where he was on staff as a gastroenterologist. The seventy-year-old woman happened to be known to Dr. Quinlan; in fact, she had recently been to see him for an endoscopy procedure. The woman now had fatigue, vomiting, abdominal pain, dark urine, and jaundice—classic symptoms of hepatitis. She had already tested negative for the most common types of viral hepatitis—types A and B. A review of her medications and recent activities made drug- or toxin-mediated hepatitis unlikely. She hadn’t been tested for hepatitis C (HCV) because she didn’t have any of the risk factors, such as drug use or a transfusion before blood was routinely tested. For completeness, Dr. Quinlan suggested they perform an HCV test. When the test returned positive the hospital physicians were puzzled by the results. Dr. Quinlan continued his busy medical practice but soon encountered a second, then a third patient with unexplained hepatitis. Like the first woman, both new patients were elderly, had abdominal pain, malaise, dark urine, and jaundice, and had undergone procedures in his center in the weeks before becoming ill. Neither had risk factors to explain their diagnoses of HCV. Increasingly disturbed, Dr. Quinlan could not convince himself that there wasn’t a connection. He was a careful man and took his infection control training seriously. How could it have happened? He hoped there was another explanation. By the time he called the New York State Health Department to report his findings, there was a fourth case. The State referred the investigation to Dr. Layton but requested to be kept in the loop.

HCV is a virus that specifically attacks the liver. It is composed of ribonucleic acid (RNA) and is considered a blood-borne virus, transmitted by blood or body fluids, like hepatitis B and HIV. It was first recognized as a unique entity in the 1970s and was referred to as non-A, non-B hepatitis, until 1988, when it was identified as a new virus. Infection with HCV is often asymptomatic; only about a quarter of those who contract it have acute symptoms. But like hepatitis B, it can become chronic with long-term complications of liver cirrhosis and cancer. There is a lag between exposure and the onset of illness in those persons who develop acute infections. The lag, or incubation period when the virus is replicating but not causing any symptoms, is two to twelve weeks but can be as long as six months. Acute symptoms when they occur include fever, fatigue, loss of appetite, nausea, vomiting, abdominal pain, dark urine, and jaundice.

Testing for HCV at the time of the investigation occurred in two steps. First, the enzyme immunoassay (EIA) antibody test was performed to look for evidence that the body had mounted a response to the virus. The test isn’t specific, meaning other illnesses might cross-react giving a false positive result. So, if positive, the test is confirmed by a more specific test called recombinant immunoblot assay (RIBA). The RIBA tests for RNA sequences specific to HCV. Persons recently infected and still incubating HCV might be negative on the EIA. A third test using PCR can be performed to detect viral RNA in such patients. However, not all HCV patients will have circulating RNA in their blood. In fact, about one-third of persons infected with HCV will clear the infection within six months. Patients positive for RNA can have their HCV genotyped, a useful method for distinguishing possible sources.

Dr. Mike Phillips had made a career and life change. Married to a surgeon and living in New Hampshire, he applied and was accepted to the CDC Epidemic Intelligence Service (EIS). EIS is a two-year public health training program for medical and epidemiology practitioners wanting to advance their skills. EIS officers are stationed either in Atlanta at the CDC or in the field at a state or city health department. Tall with blond hair and family roots in Australia, the Baltimore native had trained in infectious disease and was looking for a change of career and venue. His marriage had dissolved so when he was accepted into the EIS program he chose NYC as his assignment. Affable, hard working with attention to detail, and affectionately nicknamed Big Bird, Mike arrived in NYC in August of 2000. He was fond of saying, “You know what’s interesting?” after which he would share something he had learned. He immediately fit in with the D✪Ds.

On a short-sleeved May morning, Mike and I took the R train to Southeast Brooklyn. We walked several long blocks and crossed over the Brooklyn Queens Expressway until we arrived at Dr. Quinlan’s endoscopy center, a single-story building painted beige and shaded by trees. Dr. Quinlan was cordial, concerned, yet anxious. He showed us around and introduced us to the staff which numbered eleven: Dr. Quinlan, a second gastroenterologist who worked part-time, one anesthesiologist, one medical assistant, six office staff, and one housekeeping staff. At the moment of our arrival, we knew of eight patients with suspected HCV. All eight patients had an endoscopy procedure at the center during a narrow window between March 28–31. For the initial investigation, we expanded the period of interest to eight days by adding two days before and two days after the implicated procedure dates to capture any additional cases. One of our first tasks was to confirm the diagnoses and explore all explanations for the illness. We obtained appointment books, reviewed medical charts, interviewed each staff member alone, and examined the center’s infection control practices.

The prevalence of HCV in New York City was estimated in 2013 to be between 1.5 and 5 percent in a study performed by Sharon Balter and Katherine Bornschlegel. Higher rates were found in poorer communities. Worldwide the prevalence was estimated in 2016 to be 2.5 percent. Genotype 1 is the most common at 49 percent and has a worldwide distribution while genotype 3 is the second most common genotype at 18 percent, and is found mostly in India, Scandinavia, and parts of Southeast Asia. Genotype 4 ranks just behind at 17 percent and is found in Central Africa, Egypt, and Saudi Arabia. Genotype 2 accounts for 11 percent of cases and maps to West Africa. Genotypes 5 and 6 account for less than 5 percent and are found in South Africa and Vietnam, respectively.

HCV is primarily transmitted by the blood of infected individuals but risk factors for contracting HCV have changed over time. The ability to screen blood for HCV in the United States began in 1992, so persons who received a transfusion prior might have been exposed, particularly in countries with high HCV prevalence rates. Persons undergoing hemodialysis are at an increased risk. Sharing needles by persons using intravenous drugs is currently the primary way the disease is transmitted. Tattooing and sexual intercourse have also been implicated. HCV is not transmissible through casual contact, not through the respiratory route, nor by food.

Nosocomial transmission, which occurs in a hospital or other medical facility, of HCV has been uncommon but perplexing when it has been documented. In the early 1990s, a cardiac surgeon in Spain who was chronically infected with HCV was found to have transmitted the infection to five patients during open-heart surgery. In 1998 an anesthesiology assistant in Germany contracted HCV from a patient, and while incubating the disease, then transmitted it to five patients. The anesthesiologist had a wound on his finger before becoming infected, however, neither of these episodes have been adequately explained.

Don Weiss is an epidemiologist and author of Disease Detectives: True Stories of NYC Outbreaks.