New York - The United Nations health agency has reiterated that countries need to remain prepared for the H1N1 virus, noting that the world has not yet hit the peak influenza season between January and February when more cases are expected.
"It is completely expected that they will be seeing more influenza cases at this time, and that they will continue to see more," Gregory Hartl, spokesperson for the World Health Organization (WHO), told a news conference in Geneva.
An H1N1 update issued by the agency last week indicated that large parts of North America and parts of Europe were already over what WHO calls the epidemic threshold, so there is substantial influenza activity and more is expected.
Hartl said the indication was that this would become widespread across the Northern Hemisphere and temperate zones as these areas move forward through the late autumn and winter.
In a related development, WHO has deployed a team of experts to Ukraine, following a request from the Government, which has recorded more than 250 000 cases of influenza-like illness.
"As the pandemic virus has rapidly become the dominant influenza strain worldwide, it can be assumed that most cases of influenza in Ukraine are caused by the H1N1 virus," the agency said in a statement.
The team will begin initial work in the Lviv region, where reported numbers of cases showing severe manifestations of acute respiratory illness have been especially high.
While many questions remain to be answered, WHO stated that the outbreak in Ukraine may be indicative of how the virus can behave in the Northern Hemisphere during the winter season, particularly in health care settings typically found in Eastern Europe.
Despite concerns about the side effects of the H1N1 vaccine, WHO said it remains one of the best tools available to fight the virus.
"It has already been administered to hundreds of thousands of people. And so far we have not seen any severe side effects, and the number of side effects or adverse events, as we would call them, from this vaccine is in line with what we would expect from a seasonal flu vaccine.
"Remember this vaccine is no different from any other vaccine in the sense that all vaccines will on rare occasions produce adverse events," he noted, pointing out that the advantages of getting vaccinated far outweigh the risks at this point.
As of the end of October, there have been more than 440 000 laboratory confirmed cases of pandemic influenza H1N1 worldwide and over 5 700 deaths reported to WHO.
Meanwhile, the South African Department of Health has urged travelers to the northern hemisphere to remain on high alert and exercise caution as part of minimising the risk of contracting the H1N1 virus.
The department said the number of H1N1 Influenza cases in South Africa had decreased considerably for the last three weeks with the exception of one case reported on Sunday.
As of Monday, the country had confirmed 12 619 cases of H1N1 and 91 deaths.