Recombinomics: Pandemic H1N1 Cluster in Buffalo New York Raises Concerns

Commentary

Pandemic H1N1 Cluster in Buffalo New York Raises Concerns
Recombinomics Commentary 12:44
June 22, 2009

Davis was an eighth grader at Harvey Austin School 97 on Sycamore Street.
News 4 talked to the 15-year-old's mother Lucretia Belton. Matthew attended Harvey Austin School 97.
His mother said complications from swine flu included pneumonia and MRSA.
She said his kidneys were failing, and he was being kept alive by machines.
A nine-year-old girl is also at Women and Children's Hospital with the H1N1 virus.
She's a fourth grader at Charles Drew Science Magnet School 59's museum campus.

The above comments describe two students of magnet schools in Buffalo, NY that are a mile apart (see updated map). Both students were on life support yesterday, and the middle school student (15) died after life support was withdrawn. The elementary school student (9F) remains on life support. The clustering of two critically ill students raises concerns about the emergence of a more lethal strain of Pandemic H1N1.

The two serious cases may simply reflect the high level of H1N1 infections in the area. 37 Buffalo area zip codes have registered at least one confirmed H1N1 case (see map and list below). Moreover adjacent Niagara County announced clusters of cases in two elementary schools, and clusters were also described for Hamilton Ontario, just across the border from Buffalo and Niagara county (see map). Moreover, H1N1 has been widespread in the Halton area, where infections have been confirmed in more than 30 schools in Oakville.

However, the state agency and media reports do not describe any pre-existing conditions for either student and these two cases follow two announcements by the city of New York of 14 deaths in May. Seven were announced on Tuesday, and seven more were announce on Friday, but these announcements lacked detail. All had died in May and all were between the ages of 25-64. However, there was no additional information and no mention of pre-existing conditions.

The significance of the failure to mention pre-existing remains unclear. Many of the prior death were said to have pre-existing conditions, but there was little evidence pointing to a strong role of these conditions in the deaths. In Mexico, most of the fatalities were in young adults who did not have pre-existing conditions. Although reports of US cases have stated that 70% of fatalities had pre-existing conditions, it remains unclear if such figures include the 14 cases announced by NYC or other cases that have been confirmed but not announced.

Recent comments in press conferences by WHO and the CDC have added to the uncertainty. At the WHO press release introductory remarks by Kieji Fukuda cited 249 deaths worldwide, which raised questions, since the official tally at the time was only 140 deaths. Last week at the CDC press conference, opening remarks by Dan Jerrnigan indicated that 40% of the fatal cases had pre-existing conditions, which was much lower than the 70% cited for the released cases. In both instances the press conference transcript was edited to reflect the numbers for the released cases. However, the delay in the acknowledgement of the cases in New York raises concerns that the higher number of fatal cases and the lower percentage of cases with pre-existing condition reflects the current number of confirmed cases, which includes a high percentage of fatal cases without pre-existing conditions.

The clustering of the critical cases in Buffalo raises concerns of a Pandemic strain that is evolving and becoming more lethal. The 2009 Pandemic is tracking with the 1918 Pandemic, which produce mild disease in the spring, and was more lethal in the fall when previously healthy young adults.

One such change that could increase lethality is PB2 E627K. This polymorphism is present in seasonal influenza A, including the 1918 pandemic strain. It allows for optimal replication at lower temperatures, which may lead to a more transmissible and lethal Pandemic strain. This change has been reported for an isolate from Shanghai from a patient (22F) who recovered. The collection date, location, age and gender, suggests that the isolate came from a Chinese national who was a student in the US and flew to Shanghai on a flight that originated in New York with a lay-over in Hong Kong. Thus, the virus could have originated in New York, Hong Kong, or Shanghai, since the student developed symptoms shortly after arriving in Shanghai. The sequencers in China promptly released full sequences on all eight gene segments, and sequenced a clone to confirm that the E627K was not a sequencing error. The sequence of the clone exactly matched the original sequence.

However, this change may not offer much advantage at this time of the year in the northern hemisphere, but the change could appear in the southern hemisphere or could signal a change that is more widespread and circulating in the Hong Kong area. In any event, the presence of E627K in pandemic H1N1 strongly suggests that it will emerge in the fall, which is cause for concern.

The Buffalo cluster however raises concerns of additional changes, so sequencing of the isolate from the fatally infected middle school student would be useful.

Buffalo Area Zip Codes with at least 1 confirmed H1N1 case

14031
14032
14043
14051
14059
14068
14072
14075
14086
14127
14150
14201
14203
14204
14206
14207
14208
14209
14210
14211
14212
14213
14214
14215
14216
14217
14218
14219
14220
14221
14222
14223
14224
14225
14226
14227
14228

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