PETALING JAYA: The spread of influenza or influenza-like illness (ILI) in the community will depend on the population’s immunity and extent of social interactions, say medical experts.
Universiti Putra Malaysia epidemiologist Assoc Prof Dr Malina Osman said 35% to 45% of ILI cases were caused by influenza viruses, while others were from respiratory viruses such as human respiratory syncytial virus (HRSV) and human parainfluenza viruses (HPIV), including parainfluenza virus type 4, rhinovirus, adenovirus, human coronaviruses and human metapneumovirus.
“Influenza virus illnesses usually have a certain pattern in temperate countries, depending on seasons, while in tropical countries like Malaysia, ILI can occur throughout the year.
“There are vaccines produced against influenza yearly depending on mutations or the emergence of variants,” she said.
She said lower immunity and increased social interactions will increase the spread of ILI.
“During this transition to endemic phase, we should be continuously vigilant to monitor the spread as ILI may also be one of the features of Covid-19 infection,” she said.
Prof Malina said ILI infection was similar to Covid-19, which is through direct contact with body fluid that can be transmitted through the eye, nose and mouth or through droplets in close confined spaces.
She said symptoms included high grade fevers at above 38.5ºC with prominent respiratory symptoms like coughs, nasal congestion, sore throat and localised chest pain or tightness related to respiration; or vomiting and convulsions for infants.
She said worsening symptoms could develop quite abruptly within 48 hours and will be persistent for more than three to five days.
Universiti Malaya epidemiologist Prof Datuk Dr Awang Bulgiba Awang Mahmud said there have been reports of co-infection of Covid-19 and influenza, although it may not be very common.
However, he said he could not find published evidence to show that people who recovered from Covid-19 had increased risk of getting ILI.
“They are caused by different viruses and someone who has been infected with Covid-19 can be infected with influenza. It is advisable for people who recovered from Covid-19 to practise non-pharmaceutical interventions and get vaccinated against influenza to reduce the risk of contracting an ILI or influenza,” he said.
Dr Awang Bulgiba said if someone contracted severe Covid-19 because of a weakened immune system, that person was also likely to contract severe influenza or ILI due to the very same reason.
“This is not because of the nature of the SARS-CoV-2 virus but the reduced immune status of the individual,” he said.