The pervasive flu is among the most unpredictable infections there is. Each year, public health experts throw up their hands and declare it’s impossible to predict the timing, severity, and length of the flu season. The only thing they can foretell with absolute surety is that the flu season will begin with the winter setting in, peak in December through February in the northern hemisphere, including India, before petering out when the weather warms up.
Among the most feared flu viruses is the H1N1, popularly referred to as swine flu, which triggered unprecedented concern in India last year after it caused 1,000 infections and 218 deaths.
Despite the relatively few infections and deaths, so great is the fear of H1N1 after the first few dozen confirmed infections that everyone with a cough and fever queues up to get tested for it. Those who didn’t and fell ill regretted not getting tested. And those who got tested and recovered without a blip fretted over the money and time wasted getting tested and worrying.
Flu for all
Hundreds of thousands fall ill with the flu in India each year, many of us more than once. Children, on average, get three to six episodes of fever. All flu viruses - these days, a permutation-combination of A (H1N1) viruses, influenza A (H3N2) viruses, and influenza B viruses -- cause symptoms of cough, cold, body ache and fever that usually last for five days to a week. Viral infections are self-limiting and resolves on its own and if the symptoms are limited to cough, runny nose or fever, all you need is rest and symptomatic treatment. Paracetamol to bring down the fever, steam inhalation to unblock nasal passages, and warm liquids to soothe the throat will usually have you back on your feet within a few days. There is no need for medical management, certainly not for antibiotics used to treat bacterial infections.
Breathlessness, rash or vomiting could be signs of complications that would need treatment. In newborns, visiting a paediatrician becomes a must if the baby has an increased respiratory rate, difficulty feeding or develops raspy breathing.
Influenza viruses usually causes death by aggravating existing chronic diseases such as congestive heart failure, diabetes and lung disease (chronic obstructive pulmonary disease), so flu is seldom listed as a cause of death on death certificates. Most people die of flu-related complications such as pneumonia and multi-organ failure, not the infection itself. Often, even people who are hospitalised for flu-related complications are not even tested for flu.
In many cases, death occurs one or two weeks after infection, either because it takes time for the flu-related complication to worsen or because the person dies of a secondary bacterial co-infection such as a staph infection. Since flu tests are likely to detect the virus from respiratory samples only if the test is done within a week after the symptoms appear, results from tests done later come up negative.
A person with flu can infect others up to about six feet away. Flu viruses mainly spread through droplets made when infected people cough, sneeze or talk and these droplets are inhaled by people around them or land on surfaces. Touching a contaminated surface or object and then touching your mouth or nose also causes infection.
People with the flu are contagious from the day before symptoms start till about the fifth day of symptoms. The only way to protect yourself is to stay away from sick people and wash your hands frequently to avoid the spread of germs from contaminated surfaces. If you are sick with flu, stay home away from people so you don’t infect others.
Prescription antiviral medicines -- oseltamivir, zanamivir and peramivir, to name a few -- are used to treat people at high risk of complications, which includes children younger than two years, adults 65 and older, pregnant women, and people with medical conditions that suppress their immunity. Treatment with antivirals works best when begun within 48 hours of the symptoms appearing, but continues to be beneficial if given later in the course of illness.
Given the vagrancies of the virus, a new vaccine is announced before the flu season each year that offers protect against viruses expected to cause infection. The three viruses circulating this season are A/California/7/2009 (H1N1)pdm09-like virus, A/Switzerland/9715293/2013 (H3N2)-like virus, and B/Phuket/3073/2013-like virus, against which the 2015-2016 influenza vaccine is made to protect against all three. A quadrivalent vaccine is also available that protects against B/Brisbane/60/2008-like virus.
Much like climate change, flu is inevitable, so getting smart about preventing it is the only way ahead.