Camper to Camper Transmission of Tamiflu Resistant H1N1
Recombinomics Commentary 22:21
September 10, 2009
http://www.recombinomics.com/News/09100902/H274Y_Camper_H2H.html
On July 8, she experienced cough and headache without fever, and on July 9 she experienced chills, worsening headache, and loose stools. Despite these symptoms, her oseltamivir dose was not increased to a therapeutic treatment dose. On July 10, the last day of the first camp session, she traveled away from camp with three family members while ill, returning on July 12, afebrile and with a cough, to attend the second session. On July 12, a rapid influenza detection test was positive for influenza A.
A second previously healthy adolescent girl, who resided in the same cabin as patient A, began oseltamivir chemoprophylaxis at a dose of 75 mg daily on July 7 after exposure to patient C. On July 10, patient B left camp for a home visit during the break between camp sessions. The next day, while at home, she experienced onset of fever (101.9ºF [38.8ºC]), sore throat, and cough. She continued to engage in normal activities while ill, including visiting a shopping mall and movie theater. She returned to camp for the second session on July 12 with fever, headache, cough, malaise, and myalgias. On July 12, a rapid influenza detection test was positive for influenza A.
On August 14, CDC testing of viral RNA detected H275Y and I223V mutations
The above comments are from tomorrow’s MMWR and describe two summer campers who were infected with oseltamivir (Tamiflu resistant) pandemic H1N1 while on prophylactic Tamiflu. Since the campers shared the same cabin, and developed symptoms four days apart, it is likely that one camper infected the other. The scenario is also supported by the detection of the same rare marker, I223V, which has not been reported in other human or swine pandemic H1N1 isolates, but is present in two avian H1N 1isoaltes (see list here).
The report of this human to human transmission follows a similar report in Hong Kong, reported yesterday. In that case a younger (32M) brother was treated with Tamiflu, and his older brother (38M) developed symptoms and was positive for Tamiflu resistant pandemic H1N1 even though he had no Tamiflu exposure. Other family members were also infected, and like the younger brother, were Tamiflu sensitive, suggesting the index case was infected with a mixture and the brother was infected by the H274Y positive version, while other family members were infected with wild type H1N1.
These resistant sequences are most easily detected in patients taking prophylactic Tamiflu, because they are being monitored and symptoms while on Tamiflu raises suspicions of resistance. The Hong Kong case was discovered because of an aggressive surveillance program, which detected H274Y in an earlier traveler from San Francisco , who also had no Tamiflu exposure increasing concerns of transmission by evolutionarily fit H1N1 with H274Y.
These repeated outbreaks of H274Y on multiple genetic backgrounds of pandemic H1N1 raise concerns that the fixing of H274Y in seasonal flu, which was driven by recombination and genetic hitchhiking, will be repeated in pandemic H1N1 in the near future.
New Wisconsin swineflu article
UW-Madison takes steps to prevent massive outbreak of swine flu
http://www.lacrossetribune.com/news/local/article_ee352a7a-9ec7-11de-8bce-001cc4c002e0.html
DEBORAH ZIFF September 11, 2009
The entryway to the basement of Carson Gulley Commons on the University of Wisconsin-Madison campus isn’t blocked off with hazard tape, but visitors might want to enter at their own risk.
The Lakeshore lounge area has been transformed into an “isolation room,” as officials call it, or a space where students with flu-like symptoms can stay to avoid infecting other students.
Furnished spartanly, but stocked with thermometers, cable TV and water bottles, UW-Madison has designated a handful of such rooms across campus in an attempt to avoid a massive outbreak of swine flu, or H1N1.
College campuses are especially susceptible to such an outbreak. Like petri dishes for disease, the close quarters of dormitories create an environment where viruses are easily passed from one student to the next.
Universities across the country are creating these facilities for students to “self isolate,” as recommended by the Centers for Disease Control and Prevention, with some schools reportedly setting aside whole buildings to quarantine the sick.
Already, officials at UW-Madison’s University Health Services (UHS) are seeing more flu cases than usual for this time of year. The campus clinic reported this week roughly 200 students with flu-like symptoms since the start of school, with more than 80 percent testing positive for swine flu.
Even members of the Badgers football team missed practice because they felt ill.
Craig Roberts, an epidemiologist at UHS, said the 200 cases likely only represent a portion of the total cases on campus, because many people don’t call or visit the clinic.
And although the university has been preparing for an outbreak of the flu all summer, Roberts said the timing and number of cases was surprising.
“Across the country, most of us are quite shocked at how suddenly it started,” Roberts said. “There was nothing gradual about it.”
Students who begin to have symptoms - a fever greater than 100 degrees and a sore throat or cough - are encouraged to go home to recuperate if they live close enough to do so without taking public transportation.
But if they can’t, UW-Madison has 23 beds in six rooms across campus where contagious students can get better without coughing on healthy ones.
“The idea with isolation is you want sick people to be separated from well people, which is difficult to do in a residence hall,” Roberts said.
Only a handful of students have stayed in the isolation rooms so far, said Paul Evans, director of university housing.
The rooms have private bathrooms, and students who stay there don’t go to class and get food delivered to them. The downside, Evans said, is students tend to get bored.
UHS officials said the university is planning to hold swine flu vaccine clinics at the union, recreation centers and dorms likely beginning in October.
Amber Cook, a 19-year-old sophomore at UW-Madison, spent the second week of classes on her mother’s couch in Oregon, Wis.
After she started getting a scratchy throat and a fever on Monday, she called UHS, where a doctor told her over the phone that she had the flu and should go home. Her mom came to pick her up at her room in Tripp Hall.
“It’s really frustrating for me to sit here and know I can’t go to classes,” she said. “It’s hard enough to keep up.”
But Cook said she e-mailed her professors about her absence. Faculty and staff have been instructed in a memo from Provost Paul DeLuca not to pressure sick students into going to class.
Leniency in the face of swine flu applies to faculty and staff, too.
The University of Wisconsin System is scheduled to vote today to suspend a rule that requires sick employees to turn in doctors’ notes if they’re out for at least five consecutive days. The exemption would only apply to employees with flu-like symptoms.