All Countries Will Need Pandemic Flu Vaccine

Dr. Marie-Paule Kieny, director of the WHO Initiative for Vaccine Research, told reporters on a teleconference call today that all manufacturers and regulatory authorities are working to have the new vaccine available as soon as possible.

The vaccine for H1N1 has been produced for clinical trials, she said, but it is not ready for public release, as it is still in the experimental stage.

Young girls in Quito, Ecuador. June 23, 2009 (Photo by GillyBean4)

The results of some clinical trials will be available by September, Dr. Kieny said, but those regulatory authorities who want to have a better handle on results of clinical trials, may take until to the end of the year before they decide whether or not to immunize their populations.

"Many countries have provisions in their laws that if there is an emergency they can use vaccines with good, yet not complete, data from clinical trials without waiting for full registration of the vaccines," she said.

On July 7, the Strategic Advisory Group of Experts on Immunization, known as the SAGE Group, held an extraordinary meeting in Geneva to discuss issues and make recommendations related to vaccine for the pandemic (H1N1) 2009.

SAGE reviewed the current pandemic situation, the current status of seasonal vaccine production and potential A(H1N1) vaccine production capacity, and considered potential options for vaccine use.

The experts identified three different objectives that countries could adopt as part of their pandemic vaccination strategy:

• protect the integrity of the health-care system and the country's critical infrastructure
• reduce morbidity and mortality
• reduce transmission of the pandemic virus within communities

The SAGE Group recommended to WHO Director-General Margaret Chan that all countries should immunize their health-care workers as a first priority to protect the essential health infrastructure. As vaccines available initially will not be sufficient, a step-wise approach to vaccinate particular groups may be considered.

Healthy young woman wears pandemic flu mask at a train station in Bangkok, Thailand. July 8, 2009. (Photo by Adrian Callan)

SAGE suggested the following groups for consideration, noting that countries need to determine their order of priority based on country-specific conditions: pregnant women; those aged above six months with one of several chronic medical conditions; healthy young adults of 15 to 49 years of age; healthy children; healthy adults of 50 to 64 years of age; and healthy adults of 65 years of age and above.

Since new technologies are involved in the production of some pandemic vaccines, which have not yet been extensively evaluated for their safety in certain population groups, it is very important to implement post-marketing surveillance of the highest possible quality, the SAGE Group recommended.

In addition, rapid sharing of the results of immunogenicity and post-marketing safety and effectiveness studies among the international community will be essential for allowing countries to make necessary adjustments to their vaccination policies.

In view of the anticipated limited vaccine availability at global level and the potential need to protect against "drifted" strains of virus, SAGE recommended that promoting production and use of vaccines such as those that are formulated with oil-in-water adjuvants and live attenuated influenza vaccines is important.

Adjuvants are pharmacological or immunological agents that modify the effect of other agents, such as vaccines, while having few if any direct effects when given by themselves.

As most of the production of the seasonal vaccine for the 2009-2010 influenza season in the northern hemisphere is almost complete and so is unlikely to affect production of pandemic vaccine, SAGE did not consider that there was a need to recommend a "switch" from seasonal to pandemic vaccine production.

Dr. Chan endorsed these recommendations on Saturday, recognizing that they were well adapted to the current pandemic situation, but she noted that the recommendations will need to be changed if and when new evidence becomes available.

On June 11, the World Health Organization signaled that a global pandemic of H1N1/09 was underway by raising the worldwide pandemic alert level to Phase 6. This action was a reflection of the spread of the new H1N1 virus, not the severity of illness caused by the virus.

At the time, more than 70 countries had reported cases H1N1/09 infection and there were ongoing community level outbreaks in multiple parts of the world.

Less than one month later on July 7, WHO said that 137 countries, territories, and areas are reporting laboratory-confirmed cases, including 120 countries. At that time, WHO had received over 98,000 reports of laboratory-confirmed cases and over 440 deaths among those cases.

The virus is spreading quickly through the Southern Hemisphere, which has moved into its winter season, with cases reported in 12 African countries in the past several weeks, WHO's Dr. Keiji Fukuda said on July 7.

Southern Hemisphere countries are seeing a mixed picture depending on the country, Dr. Fukuda said. "For example, in Chile, it was just reported that over 99 percent of their influenza viruses are the new pandemic H1N1 virus. By contrast, in Australia, they see more of a mixed picture, where they are seeing both the pandemic H1N1 virus but they are also seeing a seasonal H3N2 virus that circulates there," he said. "Then, if we go down to South Africa, right now the seasonal influenza viruses are much more predominant than the pandemic influenza viruses."

In the United States, which is now in its summer season when influenza is less prevalent, the latest statistics released by the Centers for Disease Control and Prevention on July 10 show 37,246 confirmed and probable cases with 211 deaths since April 15, 2009 when the first U.S. case diagnosed. The disease has appeared in all 50 states and three territories.

U.S. Disaster Medical Specialist Teams take part in a pandemic flu exercise. June 30, 2009. (Photo courtesy TEEX)

As part of the federal government's pandemic preparedness program, members of Disaster Medical Specialist Teams from across the United States participated in a full-scale exercise sponsored by the U.S. Department of Health and Human Services at the Texas Engineering Extension Service's Disaster City on June 30.

The exercise simulated the teams' ability to set up operations at a port of entry into the United States and provide patient screening, assessment, triage, treatment, isolation and quarantine in response to a suspected pandemic flu event.

H1N1/09 is a new flu virus of swine origin that first caused illness in Mexico and the United States in March and April 2009. The new flu strain spreads in the same way that regular seasonal influenza viruses spread, mainly through the coughs and sneezes of people who are sick with the virus, but it may also be spread by touching infected objects and then touching your nose or mouth.

The pandemic H1N1 infection has been reported to cause a wide range of flu-like symptoms, including fever, cough, sore throat, body aches, headache, chills and fatigue.

An official from the Centers for Disease Control and Prevention said June 26 that the nation had its largest weekly increase in cases since the beginning of the H1N1/09 flu outbreak and that the virus has so far been detected at 34 summer camps in 16 states.

Dr. Anne Schuchat, the director of National Center for Immunization and Respiratory Diseases, told reporters, "The key point is that this new infectious disease is not going away."

States reporting widespread pandemic flu activity are Arizona, Connecticut, Delaware, Hawaii, Maine, New Jersey, New York, Pennsylvania, Rhode Island, Utah, and Virginia. Nine others are reporting regional activity.

"Virtually all of the influenza that's circulating and getting a diagnosis is this new strain," said Dr. Schuchat.

Clinical patterns in patients who are sick with the pandemic flu strain are staying constant, with the highest illness rates in people younger than age 25, she said, adding that the median age of those hospitalized with more severe illnesses is 19. However, the median age of people who are dying from the H1N1/09 virus is quite a bit older, 37.

"We haven't finalized the plans," for distributing the H1N1 vaccine when it becomes available, she said, "but states should be thinking about younger people, pregnant women, and people with chronic medical conditions. It's very important for planning to go on."

Copyright Environment News Service, ENS, 2009. All rights reserved.