Recombinomics: Suspect Swine H1N1 Toddler Death in NY Raises Concerns

Commentary

Recombinomics Commentary 17:02
May 19, 2009

A medical examiner will determine if the 16-month-old boy who died shortly after arriving at Elmhurst Hospital in Queens is the second death from swine flu in New York City.

Family members say the boy was turning blue as they rushed him to the hospital.

The above comments on a suspect swine flu fatality in Queens, New York raise additional pandemic concerns. The number of confirmed and suspect cases in Queens has been high (see updated map), leading to more the a dozen school closings, due in part to the high number of students with flu like symptoms, as well as the confirmed swine H1N1 death of an assistant principal.

Yesterday, the suspect toddler developed a fever in the morning, was eating in the afternoon, and was unresponsive by evening, when he was rushed to the hospital and died. The sudden death, coupled with rapid development of cyanosis, are classic symptoms associated with fatal influenza cases in 1918.

In 1918 an H1N1 swine flu recombined with an H1N1 seasonal flu that led to 20-50 million fatalities, as the virus spread world wide and affected approximately 1/3 of the population. That outbreak began as mild disease in the spring and most of the fatalities were associated with outbreaks in the fall of 1918 and 1919. There were multiple waves during the outbreak, raising concerns of a similar scenario in 2009.

An efficiently transmitted swine H1N1 in the human population has not been reported since 1918, Although WHO has not yet raised the pandemic phase from 5 to 6, the sustained transmission in North America, combined with reports of community spread in Europe and Asia leaves little doubt that the 2009 pandemic has begun.

The evolution of the H1N1 is being closely monitored by sequencing labs across the world, and most isolates to date are closely related. However, the presence of avian PB2 raises concerns that the frequency of cases will not decline in the summer in the northern hemisphere, because the avian PB2 is optimal at 41 C, which would lead to efficient transmission in the summer. Moreover, the seasonal flu has the mammalian version of PB2, which has optimal activity at 34 C. However, the swine H1N1 transmitting in the summer hemisphere may acquire E627K, leading to a virus efficiently transmitting in the winter aso.

Similarly, swine H1N1 in the southern hemisphere may acquire H274Y, leading to Tamflu resistance, which could complicate treatment of the more severe cases, which may involve previously healthy young adults. Another H1N1 death (44M) was just reported in St. Louis, MO.

The strong parallels between 1918 and 2009 continue to cause concern.