Tuesday, April 6, 2010

H1N1 Outbreaks in US, Abroad Carefully Monitored

H1N1 Outbreaks in US, Abroad Carefully Monitored PDF Print E-mail
by Anthony L. Kimery
Tuesday, 06 April 2010

'We are not seeing any significant evidence of a resurgent ‘third wave’

As the deadly H1N1 flu is making a comeback in places around the world, including in the southwest United States – Georgia in particular, which has been hit particularly hard – authorities are wondering whether these new outbreaks of the influenza virus represent a worrisome “third wave,” a new mutation, or whether something else is in play that’s responsible.

Alabama and North Carolina also have reported outbreaks, Centers for Disease Control and Prevention (CDC) officials reported in their latest update on the spread of the virus. CDC warned Georgians to get vaccinated for the H1N1 flu. Georgia has one of the lowest rates of vaccination among its population, which some experts believe is likely contributing to the increase in new infections there.

Local activity has also been reported in Arkansas, Louisiana, Mississippi, Tennessee, Virginia, Hawaii, New Mexico and Puerto Rico.

Across the world in Malaysia, new A H1N1 clusters have been detected throughout the country, putting the country’s Health Ministry on high alert.

Between March 21 and 27, 83 people in Selangor, Malacca and Terengganu were confirmed infected with the virus.

Health Director General Tan Sri Dr Ismail Merican said the sudden clusters indicate the H1N1 virus is still active, but stressed that the government is on top of the new outbreaks.

The World Health Organization (WHO) reported that the H1N1 pandemic influenza remains the most prominent influenza virus circulating around the world and that the virus remains active in parts of the tropical zones of Asia, the Americas, and Africa.

Elsewhere, "an increasing trend in pandemic influenza activity for at least one week during March," according to the WHO, occurred in Guatemala, Nicaragua, El Salvador, Panama, Brazil, Peru, and Bolivia all reported.

“At present, we are not seeing any significant evidence of a resurgent ‘third wave’ in the US,” the “notable exception [being] the recent sharp increase in cases in Georgia,” HSToday.us was told be a senior government public health preparedness official.

“CDC was concerned enough to hold a conference call last week, where we learned that the state had this absolute lowest vaccination rate in the country last year. Thus it was left with a vulnerable population at a time when the virus was still in circulation.

The official said “the average vaccination rate for the whole country stands at ~ 23 percent.”

In Connecticut, in comparison, the rate is one of the highest in the country, at 43 percent.

“Other New England states also fared well in this regard, a result of their intense regional cooperative planning,” the official noted.

“Regarding H5N1, there have been sporadic reports of minor changes in viral structure, but none that have thus far led to increased transmissibility,” the official added, saying that “virulence remains the same with a consistent 60 percent mortality rate in the human population. The most recent cases are still coming from Egypt and Viet Nam. Overall, WHO’s case count now stands at 492 documented cases, with 291 associated deaths.”

Authorities continue to be concerned that as pandemic H1N1 comingles with the highly fatal H5N1 bird flu there could be a genetic “reassortment” of the two viruses, potentially resulting in a deadly new flu virus.

Writing in his latest bulletin, Michael Osterholm, director of the Center for Infectious Disease Research & Policy (CIDRAP) and director of the National Institutes of Health-supported Center of Excellence for Influenza Research and Surveillance within CIDRAP, said “recent novel H1N1 influenza developments in the southeastern region of the United States merit … attention. They're prime examples of why we must vigilantly expect the unexpected.

Osterholm pointed out “an unusual level of hospitalizations linked to lab-confirmed novel H1N1 influenza in the state of Georgia prompted CDC to call a short-notice press briefing and describe the uptick as a ‘worrisome trend.’”

“Most of the hospitalized patients are adults who have chronic medical conditions and did not get the H1N1 vaccine,” Osterholm wrote, adding “Georgia had one of the lowest rates of H1N1 vaccination last fall, and people with chronic medical conditions are among the groups considered at high risk of developing complications if they're infected by the novel H1N1 pandemic virus.

“I don't know the last time in April we've seen an increasing number of hospitalizations for influenza,” Osterholm stated, adding, “of note, the number in Georgia is similar to the number of hospitalizations seen at the height of the second pandemic wave last October. In short, the trend is unexpected. Does it portend a third wave of the pandemic? We just don't know … But I sure wouldn't rule out the possibility.”

“For now, what we do know is that what's happening in Georgia is unusual for this time of the year and that people who are getting sick enough to need hospital care did not get vaccinated and are among the groups considered to be at high risk of developing complications,” Osterholm wrote.

Meanwhile, researchers have reported in a new a study published in Science Translational Medicine that the H1N1 swine influenza virus shares an important surface protein with the virus responsible for the 1918 flu.

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