Alan Sipress - The Fatal Strain

Tuan’s fever had lasted for about two days and then subsided, his father recounted. Tuan took some aspirin, had a bath, and felt better. But the fever soon returned and spiked at 104 degrees. His head throbbed. His chest ached. He started coughing and had trouble breathing. A village medic was summoned, and Tuan was taken to the local health center, where X-rays showed a white smudge in his left lung. The center’s deputy director suspected it was severe pneumonia. Because bird flu had previously been identified in the area, Tuan was transferred to a larger hospital in the provincial capital after less than a day. There the doctors concluded he had indeed contracted bird flu and immediately rushed him to the tropical disease institute at Bach Mai Hospital.

By the time he made it to Hanoi, the X-rays showed the white smudge had clouded the entire lung. Soon it consumed the other one also. “Just from the morning to the evening and from one day to the next day, it spread very quickly,” recalled Dr. Nguyen Thi Tuong Van, deputy director of the Bach Mai Hospital ICU. The doctors gave him oxygen to ease his breathing, but it continued to grow more labored. After ten days they inserted a tube down Tuan’s throat and hooked him to a mechanical ventilator. The infection marched on, damaging his kidneys and liver. The pain was excruciating. “We thought it was very likely the bird flu would kill him. We were very pessimistic,” Van continued. “Then, when it seemed the situation couldn’t get much worse, it started to get better. Two weeks later, when he didn’t die, I thought maybe we could cure him.”

Tuan’s kid sister, Ngoan, helped care for him during the early days of his sickness. Researchers who later studied the genetic signature of the pathogen concluded that Ngoan may have caught the bug from her brother, noting that some genes in her virus were practically identical to his. By the time I met Ngoan at her home, she was fully recovered. A tall, somewhat gangly teen with a mane of black hair falling to the small of her back, she bubbled over with nervous energy. She told me she loved badminton, chess, and drawing. Her eyes were narrow, but in rascally moments or when feigning surprise, she’d open them wide, big and black. When her father hesitated in retelling the tale, she’d prod him with a playful slap on the leg or she’d interject with details of her own.

Ngoan said she fell ill several days after her brother. “I felt some pain in my legs and some chills,” she recounted. “I started coughing a little.” At the district health center, X-rays revealed her lungs were clear but a subsequent test came back positive for bird flu. She was quickly transferred to the Hanoi hospital, where her fever ascended to searing levels. “I felt so tired because I had so many injections and I couldn’t sleep much,” she recalled. Hospital staff moved her to the same room as her brother and the pair bantered as always to keep up their spirits, until Tuan could no longer speak. Ngoan’s older sister brought her a pad and a pen. Ngoan, who would always draw people when she was feeling down, sketched the doctors and nurses to ease her mind.

After four days, her fever broke. It returned to normal within two weeks. Barely a month after she got sick, she was back in school as something of a local celebrity.

Though the grandfather also contracted the virus, he objected that he had never felt sick and indeed had shown no symptoms. Vietnamese health officials happened across the old man’s infection while testing all the family members. To flu specialists, this was more evidence that the virus was experimenting with new, deceptive paths of infection. Though the man might not feel sick, he could possibly be contagious and, if so, how would anyone know to steer clear of him?

The nurse was the most disquieting case of all. Nguyen Duc Tinh was a tall, skinny twenty-six-year-old with an earnest manner and a whisper of a mustache. He was on duty at the local health center when Tuan was brought in. During the brief, overnight stay, Tinh took Tuan’s blood and temperature, gave him injections, and helped him walk. Within a week, Tinh had developed severe muscle aches, eye pain, and a high fever, symptoms of what he believed was ordinary flu. But when the fever subsided only to return two days later, he grew alarmed.

“Then I suspected I had bird flu,” he recalled, his brown eyes widening. “I was really, really afraid of dying.” But just two weeks after being reunited with Tuan in the Hanoi hospital, Tinh was discharged. “I had lost hope when the fever came a second time. When I returned to my hometown, I felt as if I were born again.”

Vietnamese officials were loath to admit he might have caught the disease by caring for Tuan. This could be an admission that a more dangerous strain was taking hold. They offered a raft of possible explanations for how Tinh got sick: He had sick chickens in his village. There were sick chickens at his girlfriend’s home. He’d eaten a sick chicken. He had eaten it at his girlfriend’s home.

Tinh dismissed them all with a snicker. “I haven’t had any direct contact with poultry or eaten chicken or duck in a long time,” he countered. Nor had he dined at his girlfriend’s house for weeks before he fell ill, and, thank you very much, all her chickens were healthy. “But,” he added, “I was the one in the health center who had the closest contact with Mr. Tuan.”

A rare voice of candor among Vietnamese officials was Dr. Nguyen Tran Hien, the astute and able head of the National Institute of Hygiene and Epidemiology (NIHE), the country’s CDC. He told me in April of that year that his researchers had identified a significant number of mild and even asymptomatic cases, like Tuan’s grandfather. “The symptoms are not as severe as before. Also, the transmission may be faster and easier,” he reported. “We are concerned that if the virus is changing, maybe a new virus is coming in the future.” Hien wanted more data. And he wanted outside expertise.

Keiji Fukuda returned to Hanoi in mid-April 2005 as part of a special WHO mission. Fukuda was still with the CDC in Atlanta and would not officially transfer to WHO for several more months. But his standing and experience in Vietnam made him a natural for the assignment. Joining him was Dr. Aileen Plant, a fellow epidemiologist from Curtin University of Technology in western Australia known for her passion and wicked sense of humor. Plant had headed WHO’s highly successful response to SARS in Vietnam two years earlier. The third member was Dr. Lance Jennings, a virologist from the Canterbury Health Laboratories in New Zealand and his country’s acknowledged authority on flu.

For about a week, they shuttled from the WHO offices on Tran Hung Dao Street in downtown Hanoi to the handsome French colonial edifice that houses NIHE about a mile away. That grand old building, with its warm, mustard-colored facade and gray shuttered windows, is located on a street named for a foreign disease detective, Alexandre Yersin, the French-Swiss bacteriologist who discovered the pathogen causing bubonic plague a century ago and later adopted Vietnam as his home. There, down the elegant, high-ceilinged corridors of NIHE, Fukuda and his team huddled with their Vietnamese counterparts, reviewing their findings.

“We were looking at everything we could look at,” Fukuda recalled. “Was there an increase in cases? Any differences of patterns in cases? Anything different about the people who were getting infected themselves, and so on.” The evidence wasn’t conclusive. “But on the other hand, it began to appear there were some differences from earlier patterns in Vietnam.”

During the previous year, bird flu had killed nearly three-quarters of those Vietnamese it infected. Yet over the first few months of 2005, the mortality rate had dropped by more than half, suggesting that the virus was edging closer to a pandemic strain. The shift was especially conspicuous because it took place only in the north of the country. The cases were also increasingly coming in family clusters, and often the time that elapsed between cases within the clusters was growing, making it ever more likely that relatives were passing the disease to one another rather than all catching it from the same source. Nine cases were from Thai Binh alone, including Tuan’s cluster.