Category Archives: Swine Flu

Pandemic (H1N1) 2009, Ukraine

On 28 October 2009, the Ministry of Health of the Ukraine informed WHO, through its Country Office in Ukraine, about an unusually high level of activity of acute respiratory illness in the western part of the country, associated with an increased number of hospital admissions and fatalities.

Clinical features of severe cases of pandemic influenza

To gather information about the clinical features and management of pandemic influenza, WHO hosted a three-day meeting at the headquarters of the Pan American Health Organization in Washington, DC on 14–16 October. Findings and experiences were presented by around 100 clinicians, scientists, and public health professionals from the Americas, Europe, Asia, Africa, the Middle East and Oceania.

Antiviral use and the risk of drug resistance

Growing international experience in the treatment of pandemic H1N1 virus infections underscores the importance of early treatment with the antiviral drugs, oseltamivir or zanamivir. Early treatment is especially important for patients who are at increased risk of developing complications, those who present with severe illness or those with worsening signs and symptoms.[1]

Pandemic influenza vaccines: current status

Regulatory authorities have licensed pandemic vaccines in Australia, China, Hungary and the United States of America, soon to be followed by Japan and several countries in Europe. The length of the approval process depends on factors such as each country’s regulatory pathway, the type of vaccine being licensed, and the stage of manufacturers’ readiness to submit appropriate information to regulatory authorities.

Pandemic (H1N1) 2009 – update 66

In the temperate regions* of the northern hemisphere, influenza activity remains widely variable. In North America, the United States is reporting increases in influenza-like-illness activity above the seasonal baseline, most notably in the southern, southeastern, and parts of the northeastern United States.

In Canada, influenza activity remains low. In Europe and Central Asia influenza activity remains low overall, except in France, which is reporting increases in influenza-like-illness activity (for week 37) above the seasonal epidemic threshold. Geographically localized influenza activity is being reported in several countries (Austria, Georgia, Ireland, Luxembourg, Norway, Portugal, the Czech Republic, Cyprus, and Israel). In Japan, influenza activity remains stably increased above the seasonal epidemic threshold with the most notable increases being reported on the southern island of Okinawa.

In the tropical regions of the Americas and Asia, influenza transmission remains active. Geographically regional to widespread influenza activity continues to be reported throughout much of South and Southeast Asia, with increasing trends in respiratory diseases being reported in India and Bangladesh. Geographically regional to widespread influenza activity continues to be reported for the tropical regions of Central and South America without a consistent pattern in the trend of respiratory diseases (continued increases are being reported in Bolivia and Venezuela).

In the temperate regions* of the southern hemisphere, influenza activity continues to decrease or has returned to the seasonal baseline in most countries. In Australia, later affected areas are also now reporting declining levels of influenza-like-illness. In South Africa, influenza activity appears to have recently passed over the second peak (the first peak was due to seasonal influenza A (H3N2) and second peak was due to pandemic (H1N1) 2009).

WHO Collaborating Centres and other laboratories continue to report sporadic isolates of oseltamivir resistant influenza virus. Twenty six such virus isolates have now been described from around the world, all of which carry the same H275Y mutation that confers resistance to the antiviral oseltamivir but not to the antiviral zanamivir. Of these, 12 have been associated with post-exposure prophylaxis, five with long term oseltamivir treatment in patients with immunosuppression. Worldwide, over 10,000 clinical samples and isolates of the pandemic (H1N1) 2009 virus have been tested and found to be sensitive to oseltamivir. WHO will continue to monitor the situation closely in collaboration with its partners.

Pandemic (H1N1) influenza virus continues to be the predominant circulating influenza virus, both in the northern and southern hemisphere. See below for detailed laboratory surveillance update.

*Countries in temperate regions are defined as those north of the Tropic of Cancer or south of the Tropic of Capricorn, while countries in tropical regions are defined as those between these two latitudes.

Pandemic (H1N1) 2009 – update 65

In the temperate region of the southern hemisphere (represented by countries such as Chile, Argentina, Australia, New Zealand, and South Africa), influenza activity continues to decrease or return to baseline.

Active transmission persists in tropical regions of the Americas and Asia. Many countries in Central America and the Caribbean continue to report declining activity for the second week in a row. However, countries in the tropical region of South America (represented by countries such as Bolivia, Ecuador, and Venezuela) are reporting increasing levels of respiratory disease. In the tropical regions of Asia, respiratory disease activity remains geographically regional or widespread but the trend is generally increasing as noted in India, Bangladesh, and Cambodia.

In the temperate regions of the Northern Hemisphere activity is variable. In the United States, regional increases in influenza activity are being reported, most notably in the south eastern states. Most of Europe is reporting low or moderate respiratory diseases activity, but parts of Eastern Europe are beginning to report increases in activity.

WHO Collaborating Centres and other laboratories continue to report sporadic isolates of oseltamivir resistant influenza virus. 21 such virus isolates have now been described from around the world, all of which carry the same H275Y mutation that confers resistance to the antiviral oseltamivir but not to the antiviral zanamivir. Of these, 12 have been associated with post-exposure prophylaxis, four with long term oseltamivir treatment in patients with immunosuppression. Worldwide, over 10,000 isolates of the pandemic (H1N1) 2009 virus have been tested and found to be sensitive to oseltamivir. WHO will continue to monitor the situation closely in collaboration with its partners, but is not changing its guidelines for use of antiviral drugs at this time.

Pandemic (H1N1) influenza virus continues to be the predominant circulating virus of influenza, both in the northern and southern hemisphere. All pandemic H1N1 2009 influenza viruses analysed to date have been antigenically and genetically similar to A/California/7/2009-like pandemic H1N1 2009 virus. See below for detailed laboratory surveillance update.

Of note, the U.S. Centers for Disease Control and Prevention this week reported on an analysis of 36 fatal pandemic influenza cases in children under the age of 18 years. Sixty-seven percent of the children had one or more high-risk medical conditions, most commonly neurodevelopmental disorders. In addition, ten of 23 children for whom data were available were found to have strong evidence of secondary bacterial co-infections.

Measures in school settings

WHO is today issuing advice on measures that can be undertaken in schools to reduce the impact of the H1N1 influenza pandemic. Recommendations draw on recent experiences in several countries as well as studies of the health, economic, and social consequences of school closures. These studies were undertaken by members of a WHO informal network for mathematical modelling of the pandemic.

Pandemic (H1N1) 2009 – update 64

Tropical regions of South and Southeast Asia continue to experience geographically regional or widespread influenza activity (represented by countries such as India, Bangladesh, Myanmar, Thailand, Cambodia, Sri Lanka, and Indonesia). Many countries in the region are reporting increasing or sustained high levels of respiratory disease, and a few (Thailand and Brunei Darussalam) have begun to report a declining trend in the level of respiratory diseases.

In tropical regions of Central America and the Caribbean (represented by countries such as Costa Rica, El Salvador, Guatemala, Honduras, Panama, and Cuba), influenza activity continues to be geographically regional or widespread, however, most are now reporting a declining trend in the level of respiratory diseases.

Countries in the equatorial and tropical regions of South America (represented by Ecuador, Venzezuela, Peru, and parts of Brazil) continue to experience geographically regional or widespread influenza activity, with many reporting an increasing trend in the level of respiratory diseases.

Although many countries in temperate regions of the southern hemisphere (Chile, Argentina, Australia, and New Zealand) have passed the peak of their winter influenza epidemic, sustained influenza activity continues to be reported in South Africa and in the Southern and Western parts of Australia.

In temperate regions of the northern hemisphere, there are wide geographical variations in the level of influenza activity being reported. In Japan, influenza activity continues to increase past the seasonal epidemic threshold, indicating an early beginning to the to annual influenza season. In Canada and the United States, influenza activity remain low overall, however regional increases are being detected in the Southeastern United States. In Europe and Central and Western Asia, although little influenza activity is being reported, a few countries are reporting geographically widespread influenza activity (Austria and Israel) or an increasing trend in respiratory diseases (Netherlands and Romania).

Pandemic (H1N1) influenza virus continues to be the predominant circulating virus of influenza, both in the northern and southern hemisphere. All pandemic H1N1 2009 influenza viruses analysed to date have been antigenically and genetically similar to A/California/7/2009-like pandemic H1N1 2009 virus. See below for detailed laboratory surveillance update.

Pandemic (H1N1) 2009 – update 63

In the southern hemisphere, most countries (represented by Chile, Argentina, New Zealand, and Australia) appear to have passed their peak of influenza activity and have either returned to baseline levels or are experiencing focal activity in later affect areas; while a few others (represented by South Africa and Bolivia) continue to experience high levels of influenza activity.

Many countries in tropical regions (represented by Central America and tropical regions of Asia), continue to see increasing or sustained high levels of influenza activity with some countries reporting moderate strains on the healthcare system. In temperate areas of the northern hemisphere (represented by North America, Europe, and Central Asia), influenza and respiratory disease activity remains low overall, with some countries experiencing localized outbreaks. In Japan, the level of influenza activity has passed the seasonal epidemic threshold, signaling a very early beginning to the annual influenza season.

Pandemic H1N1 influenza virus continues to be the predominant circulating strain of influenza, both in the northern and southern hemisphere. Antiviral susceptibility testing has increased in several countries, confirming that pandemic H1N1 influenza virus remains sensitive to the antiviral oseltamivir, except for sporadic reports of oseltamivir resistant pandemic H1N1 virus detailed in the previous web update (No. 62).