now in Early days of 2009 Influenza Pandemic
The World Health
Organization (WHO) declared on 11 June 2009 that 'swine' flu (or influenza
caused by H1N1 virus) is a pandemic.
"On the basis of available evidence, and these expert assessments of the
evidence, the scientific criteria for an influenza pandemic have been met. I
have therefore decided to raise the level of influenza pandemic alert from
phase 5 to phase 6" said Dr Margaret Chan, Director-General of the WHO in
statement issued on 11 June 2009. "The world is now at the start of
the 2009 influenza pandemic" further said Dr Chan.
"We are in the earliest days of the pandemic. The virus is spreading
under a close and careful watch. No previous pandemic has been detected so
early or watched so closely, in real-time, right at the very beginning. The
world can now reap the benefits of investments, over the last five years, in
pandemic preparedness. We have a head start. This places us in a strong
position. But it also creates a demand for advice and reassurance in the midst
of limited data and considerable scientific uncertainty" cautioned Dr
The virus is contagious, spreading easily from one person to another, and from
one country to another. As of today, nearly 30,000 confirmed cases have been
reported in 74 countries.
This is only part of the picture. With few exceptions, countries with large
numbers of cases are those with good surveillance and testing procedures in
Spread in several countries can no longer be traced to clearly-defined chains
of human-to-human transmission. Further spread is considered inevitable.
"Thanks to close monitoring, thorough investigations, and frank reporting
from countries, we have some early snapshots depicting spread of the virus and
the range of illness it can cause" said Dr Chan.
"We know, too, that this early, patchy picture can change very quickly.
The virus writes the rules and this one, like all influenza viruses, can
change the rules, without rhyme or reason, at any time.
Globally, we have good reason to believe that this pandemic, at least in its
early days, will be of moderate severity. As we know from experience, severity
can vary, depending on many factors, from one country to another" said Dr
On present evidence, the overwhelming majority of patients experience mild
symptoms and make a rapid and full recovery, often in the absence of any form
of medical treatment.
Worldwide, the number of deaths is small. "Each and every one of these
deaths is tragic, and we have to brace ourselves to see more. However, we do
not expect to see a sudden and dramatic jump in the number of severe or fatal
infections" said Dr Chan.
The H1N1 virus preferentially infects younger people. In nearly all areas with
large and sustained outbreaks, the majority of cases have occurred in people
under the age of 25 years.
In some of these countries, around 2% of cases have developed severe illness,
often with very rapid progression to life-threatening pneumonia.
Most cases of severe and fatal infections have been in adults between the ages
of 30 and 50 years.
This pattern is significantly different from that seen during epidemics of
seasonal influenza, when most deaths occur in frail elderly people.
Many, though not all, severe cases have occurred in people with underlying
chronic conditions. "Based on limited, preliminary data, conditions most
frequently seen include respiratory diseases, notably asthma, cardiovascular
disease, diabetes, autoimmune disorders, and obesity" said Dr Chan.
At the same time, it is important to note that around one third to half of the
severe and fatal infections are occurring in previously healthy young and
"Without question, pregnant women are at increased risk of complications.
This heightened risk takes on added importance for a virus, like this one,
that preferentially infects younger age groups" added Dr Chan.
"Finally, and perhaps of greatest concern, we do not know how this virus
will behave under conditions typically found in the developing world. To date,
the vast majority of cases have been detected and investigated in
comparatively well-off countries" cautioned Dr Chan.
"Let me underscore two of many reasons for this concern. First, more than
99% of maternal deaths, which are a marker of poor quality care during
pregnancy and childbirth, occurs in the developing world. Second, around 85%
of the burden of chronic diseases is concentrated in low- and middle-income
countries" said Dr Chan.
Although the pandemic appears to have moderate severity in comparatively
well-off countries, it is prudent to anticipate a bleaker picture as the virus
spreads to areas with limited resources, poor health care, and a high
prevalence of underlying medical problems.
"A characteristic feature of pandemics is their rapid spread to all parts
of the world. In the previous century, this spread has typically taken around
6 to 9 months, even during times when most international travel was by ship or
rail" said Dr Chan.
Countries should prepare to see cases, or the further spread of cases, in the
near future. Countries where outbreaks appear to have peaked should prepare
for a second wave of infection, according to Dr Chan's statement to the press.
Guidance on specific protective and precautionary measures has been sent to
ministries of health in all countries. Countries with no or only a few cases
should remain vigilant.
Countries with widespread transmission should focus on the appropriate
management of patients. The testing and investigation of patients should be
limited, as such measures are resource intensive and can very quickly strain
"WHO has been in close dialogue with influenza vaccine manufacturers. I
understand that production of vaccines for seasonal influenza will be
completed soon, and that full capacity will be available to ensure the largest
possible supply of pandemic vaccine in the months to come. Pending the
availability of vaccines, several non-pharmaceutical interventions can confer
some protection" said Dr Chan.
WHO continues to recommend no restrictions on travel and no border closures as
per Dr Chan's statement.
Influenza pandemics, whether moderate or severe, are remarkable events because
of the almost universal susceptibility of the world’s population to
"We are all in this together, and we will all get through this,
together" said Dr Chan.
author is a World Health Organization (WHO)'s WNTD Awardee 2008, coordinates
the Stop-TB eForum Resource Team of HDN, and writes extensively on health and
development. Email: firstname.lastname@example.org)