BOTH social and mainstream media are filling up with news about influenza cases and respiratory viral outbreaks. Besides an increase in local cases of influenza, we are now being told that there is a mysterious outbreak of atypical pneumonia in China that is not unlike the SARS (Severe Acute Respiratory Syndrome) outbreak of 2003. What is influenza?
Influenza is an infectious disease caused by a virus. Unlike the colloquially-used term ‘having a flu’ - which tends to denote a common cold with a runny nose and sore throat - an actual case of influenza tends to lead to a high fever, muscle and joint aches, sore throat, headache, and severe fatigue.
There are generally two types of influenza viruses: influenza A and influenza B. Within these groups are various sub-types or strains, and the degree to which these are found in the community tend to fluctuate depending on the season.
Influenza viruses are living beings which constantly evolve, sometimes rapidly. Every so often, influenza viruses mutate enough to result in a new strain in a process known as antigenic drift. The most lethal strain caused the ‘Spanish Flu’ epidemic in 1918-1919, where as many as 40 million people died. Since then, there have been various epidemics from the ‘Asian Flu’ of the 1950s that led to the death of two million people to the more recent ‘Bird Flu’ in 2013. Should I be worried?
The vast majority of patients with influenza feel ill for several days and then recover, albeit with a feeling of lethargy that can persist for a few weeks. In a minority of cases though influenza can lead to pneumonia, complications involving other organs, and even death. Those with pre-existing illnesses such as heart failure, lung disease, kidney disease and cancer should be particularly careful.
Patients who have been exposed to influenza in the past will develop immunity to that particular strain, but not to others. Influenza vaccinations have been shown to reduce the risk of flu illnesses, hospitalisations and deaths in both adults and children. These are recommended for individuals above the age of six months, particularly the very young and elderly, those with underlying chronic disease and those who are planning to travel to countries experiencing winter or to the middle east for Umrah/Haj.
The vaccine protects against the viruses that research indicates will be most common during a particular influenza season. For example, a quadrivalent vaccine protects against four strains. After injection, it takes two weeks for antibodies to be fully formed against these viruses - in other words, the vaccine does NOT work immediately. What should I do?
Prevention is always better than cure, so a vaccine will go a long way in helping avoid influenza in the first place.
If you’ve been diagnosed with influenza, the most important thing that you can do for yourself is rest, take paracetamol and drink plenty of water. In some cases, doctors may prescribe oseltamivir, an
anti-viral medication that can potentially reduce symptoms and complications. Antibiotics are useless when treating viral infections, and should only be used if there is a concurrent bacterial infection.
It is also essential that steps be taken to prevent the spreading of influenza - the virus tends to be contagious in the first five days from the onset of fever. It spreads through air droplets - whenever the patient coughs and sneezes - and can live on hands and surfaces for up to 24 hours.
With this in mind, it is essential to practice appropriate cough etiquette which is basically covering your nose/mouth with a tissue paper whenever you sneeze or cough, disposing it properly into a bin and washing/sanitising your hands immediately afterwards. It is also advisable to quarantine one’s self both from loved ones and colleagues at work. What’s happening in China?
Occasionally, a major mutation produces a strain so different from the others that humans have little or no pre-existing immunity. Increased viral mutations and transmission are usually noted in places where there is close proximity amongst humans, and between humans and animals. For example, the ‘Bird Flu’ or avian influenza A H7N9 virus was transmitted from chickens at a wet poultry market to humans.
More than 50 people have been diagnosed with a mysterious respiratory illness over the past few days in China. These cases have been centred in Wuhan, the capital of Hubei province, and a number of patients were noted to have been working in the same market.
There are fears of SARS, a coronavirus (i.e. not influenza virus) originating from the Guangdong province of southern China in 2002 that killed hundreds. However the Wuhan Municipal Health Commission have released a statement that initial investigations have ruled out SARS, as well as Middle East respiratory syndrome (MERS-CoV), influenza, bird flu and adenovirus.
It is likely that this disease is due to a hitherto unidentified virus - similar precautions as above should be taken, alongside avoidance of travel to affected areas and strict quarantine measures for those affected.
*Dr Helmy Haja Mydin is a respiratory physician and head of the Lung Centre at Pantai Hospital Kuala Lumpur, and co-founder of Asthma Malaysia (www.asthmamalaysia.org)
**The views and opinions expressed in this article are those of the author(s) and do not necessarily reflect the position of Astro AWANI.