As of 27 Jun 2010, worldwide more than 214 countries and overseas territories
or communities have reported laboratory confirmed cases of pandemic influenza
H1N1 2009, including over 18 239 deaths.
WHO is actively monitoring the progress of the pandemic
through frequent consultations with the WHO Regional Offices and Member
States and through monitoring of multiple sources of information.
Summary: Worldwide, overall pandemic and seasonal influenza activity remain
low. In the temperate regions of the Southern Hemisphere, Chile, and Argentina
report low activity and only sporadic detections of both pandemic and
seasonal influenza viruses during the early part of winter. South Africa,
New Zealand, and Australia have all recently noted slight increases in
the rate of respiratory disease. South Africa recently reported their
1st case of confirmed H1N1; however, the predominant influenza virus there
currently is seasonal influenza A(H3N2). The H3N2 virus detected in South
Africa is similar to the Perth-like strain, which is currently a component
of the trivalent seasonal influenza vaccine.
Active transmission of pandemic influenza virus still
persists in localized areas of the tropics, particularly in South and
Southeast Asia, the Caribbean and West Africa. During the last 2 to 3
weeks, seasonal influenza H3N2 viruses have also been detected at increasing
levels in Nicaragua, and at low levels or sporadically in Australia, Central
America, South Africa and East Africa. Global circulation of seasonal
influenza virus type B viruses persists at low levels in parts of East
Asia, Central Africa, and Central America.
Regional Details: In most countries of the temperate
zone of the southern hemisphere (Chile, Argentina, South Africa, Australia,
and New Zealand), pandemic and seasonal influenza viruses have been detected
only sporadically in June 2010, and activity is low, indicating a late
start of the influenza season compared to 2008. Overall levels of respiratory
disease in the population remain low. In Argentina, small numbers of influenza
type B viruses were detected during mid June 2010. In both Chile and Argentina,
respiratory syncitial virus (RSV) continued to be the predominant circulating
respiratory virus resulting in high rates of respiratory illness in children.
In South Africa, small and slightly increasing numbers of seasonal H3N2
and type B viruses were detected during mid June 2010. In both Australia
and New Zealand, levels of ILI [influenza-like illness] are increasing
but still below recent historical seasonal levels.
the most active areas of pandemic influenza virus transmission currently
are in parts of southern India, Bangladesh, Singapore, and Malaysia. Rates
are decreasing in the latter 3 countries, but in India, the number of
laboratory confirmed cases of pandemic influenza has increased since mid
June 2010. This activity has been primarily observed in Southern state
of Kerala, and includes reports of a number of severe and fatal cases,
particularly among pregnant women.
In Bangladesh, pandemic and seasonal influenza type B
viruses co-circulated at low levels during early June 2010. In Singapore,
during the 3rd week of June 2010, the levels of ARI [acute respiratory
infection] remained below warning levels, and the proportion of patients
with ILI testing positive for pandemic influenza virus fell from 19 to
15 percent. In Malaysia, data suggest that overall pandemic influenza
activity has declined throughout June 2010, though pandemic virus continues
to circulate at low levels.
Throughout East Asia
influenza activity remained very low. In China and Japan, levels of ILI
remained at or below baseline levels for the summer months. Low and declining
levels of influenza type B viruses continued to circulate across China,
Hong Kong SAR (China), Chinese Taipei and the Republic of Korea.
In the tropical regions of the Americas
overall pandemic and seasonal influenza activity remained very low. In
Cuba, pandemic influenza virus transmission remains active but has declined
substantially since peaking during mid-April to mid-May 2010; no new fatal
cases have been reported over the past 5 reporting weeks. In several countries
of the region, there has been recent circulation
of seasonal influenza A (H3N2) viruses (Venezuela during May 2010) and
B viruses (Bolivia during March and May 2010; El Salvador during late
May and early June 2010). Nicaragua notably has seen a sharp increase
in the detection of seasonal influenza A (H3N2), and Panama has detected
low numbers of the same. In addition, after 20 weeks with no circulating
pandemic virus, Panama reported the detection of pandemic influenza (H1N1)
2009 in early June 2010. Many countries in the area also report ongoing
co-circulation of other respiratory viruses, most notably RSV.
In sub-Saharan Africa
pandemic and seasonal influenza activity has been observed in several
countries. Ghana, in West Africa, continues to have active circulation
of pandemic influenza virus several weeks after activity peaked during
early April 2010. Seasonal influenza type B viruses continue to circulate
in parts of central and southern Africa, most notably in Cameroon. As
reported in previous updates, small numbers of seasonal H3N2 viruses continue
to be detected across Africa, particularly in eastern Africa; the most
recent detections have been reported in Ghana, Kenya, and South Africa
during mid June 2010. The persistence of H3N2 in this area over time very
likely represents sustained community transmission of the virus.
Overall, in the temperate regions of the northern hemisphere
(North America and Europe), pandemic and seasonal influenza viruses have
been detected sporadically or at very low levels during the past month.