Aug 13, 2010 (CIDRAP News) Pandemic H1N1 flu activity is intense in parts of India and New Zealand and is circulating at low-to-moderate levels in a few other parts of the world, the World Health Organization (WHO) reported today.
Earlier this week the WHO declared that the H1N1 influenza pandemic was over and changed the pandemic alert phase to the post-pandemic period, but it warned that the virus was still circulating and warranted continued surveillance.
Most of the flu in India is the pandemic H1N1 virus, which doesn't appear to have peaked yet in the areas of most intense activity, which include Maharashtra, Gujarat, Andhra Pradesh, and West Bengal states, the WHO said. For the week ending Aug 8, India confirmed 79 pandemic flu deaths. In the country's Kerala state, one of the first to experience a post-monsoon spike in flu activity earlier this summer, flu appears to have peaked in early July and is declining.
Meanwhile, New Zealand is one of the few Southern Hemisphere countries reporting an increase in flu activity. Doctor's visits for flu-like illnesses have been increasing in recent weeks, with the majority of them linked to the pandemic H1N1 virus, the WHO reported. Flu activity is geographically uneven and seems to be focusing on areas that weren't hit hard during the country's first pandemic flu wave, according to the WHO.
New Zealand's health ministry said yesterday in a surveillance update that the central part of the Northern Island is currently the hardest-hit area, and it predicted that a number of areas, such as the South Island, may be vulnerable, because they did not experience high levels of transmission during the first wave of infections last summer.
So far this year the health ministry has received reports of 332 hospitalizations and 46 intensive care unit (ICU) admissions for pandemic H1N1 infections. Calls to the country's telephone flu line were running 25% higher than normal for seasonal flu.
Elsewhere, the pandemic H1N1 virus is circulating at low-to-moderate levels in some parts of the Americas, West Africa, and South and Southeast Asia.
The most active areas of seasonal influenza A/H3N2 circulation are currently in some tropical areas of the Americas, especially Central America, along with southern and western Africa and parts of Southeast Asia, the WHO reported. The focus of influenza B transmission appears to be parts of central and southern Africa.
Yesterday two experts from the European Center for Disease Prevention and Control, in a Eurosurveillance report, said that for five Southern Hemisphere countries that conduct regular flu surveillance, the 2010 flu season has seen lower levels of activity than the 2009 season. "In these countries the level of illness is looking more like inter-pandemic influenza than the pandemic levels seen in the winter of 2009," they wrote. However, they added that whether 2010 levels are normal for inter-pandemic flu is unclear, because some countries lack good baseline data.
Most of the pandemic H1N1 viruses analyzed so far are closely related to the strain included in the monovalent and seasonal flu vaccines, and the WHO said it has not received any new reports of oseltamivir-resistant pandemic H1N1 cases.
Aug 13 WHO flu surveillance report
Aug 12 New Zealand health ministry statement
Aug 12 Eurosurveillance report