2 weeks ago
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As flu season is expected to start soon, there are ways to protect yourself and others. We asked Dr Jocelyn Moyes, a medical epidemiologist from the National Institute for Communicable Diseases (NICD), to answer some questions about the flu.
When does flu season start?
Moyes said that over the last 20 years (excluding the pandemic years between 2020-2022), the influenza season generally started between mid-April and early June. It peaks in late June or early July and ends in August or September.
Which variants will be most in circulation this year?
Influenza viruses constantly change their antigenic structure, so it is impossible to predict which strain(s) will circulate. In most years, there will be a mix of strains.
Does it matter which of the flu strains you have?
“Influenza from any strain is a self-limiting illness for most people, and people will recover in 3-7 days. However, influenza can cause severe illness, hospitalisation or even death in some people.
“All influenza strains can cause severe disease. The annual influenza vaccine (available in public health clinics and private facilities) can prevent illness and protect against severe disease.
“The vaccine is changed yearly to match the expected circulating viruses. People at risk of severe illness are strongly encouraged to get vaccinated,” she added.
Who is at risk of severe illness?
Moyes listed these categories as: pregnant women and women who gave birth within the previous six weeks; people living with HIV; individuals with tuberculosis; persons of any age with chronic diseases, especially those affecting lungs like asthma; those who require immunosuppressive medication or cancer patients; people who have been diagnosed with cardiac disease (except hypertension); people with diabetes and other metabolic diseases; and those with renal or hepatic (liver) diseases or neurologic and blood conditions.
Moyes also advised that people older than 65 get vaccinated and those younger than 18, including children, receive chronic aspirin therapy.
Should we still test for Covid?
The NICD continues to do surveillance for SARS-CoV-2 to describe the circulation and identify the variant circulating. There is no indication for individuals to test for SARS-CoV-2, unless it is needed for medical management of their illness.
What are the current respiratory diseases circulating?
“SARS-CoV-2 has been circulating at low levels for two years, with no indication of the circulation becoming seasonal. The RSV [respiratory syncytial virus] season in South Africa starts in mid-February, peaks in April or early May and ends in early June, preceding the influenza season.
“In our surveillance programmes, the peak of RSV circulation for 2024 has been reached and the detection rate is decreasing,” said Moyes.
Which respiratory diseases are in circulation?
The disease currently identified by the NICD’s surveillance programmes is flu, although the season has not yet started (based on predetermined thresholds).
Pertussis is a vaccine-preventable illness caused by the bacterium Bordetella pertussis. It’s commonly known as whooping cough.
“From July 2021, we detected an increase in the circulation of pertussis across the country (mostly in young children), lasting until mid-2023. Since then, the numbers have decreased dramatically, and we are only picking up sporadic cases now,” Moyes said.
“Some respiratory viruses other than RSV, influenza and SARS-CoV-2 can cause similar symptoms, including adenovirus, rhinovirus, enterovirus, parainfluenza and human metapneumovirus. These viruses can circulate all year round but may increase seasonally,” she added.
How can we protect ourselves?
Moyes said the best way to protect yourself is to get the flu vaccine (for influenza) and implement similar measures to those used during the pandemic.
These include frequent hand-washing, respiratory hygiene (cough/sneezing into a tissue or your elbow), wearing a mask when you have respiratory symptoms (to protect other people) and isolating if you are ill to avoid spreading viruses.
How vital is it to get the vaccine?
Moyes said it is vital for people in the high-risk group.
“For others, it is advisable, particularly if they wish to reduce their chances of becoming ill, being absent from work or spreading the virus to other vulnerable individuals.”
Is there a new strain of Covid that we don’t know about doing the rounds?
Moyes explained that the SARS-CoV-2 is constantly evolving, but there is no new variant doing the rounds at the moment.
“The virus has been circulating at a low level since the end of the pandemic,” she said.
She added that current Covid levels are low, with little change in the past two years.
According to the latest genomic surveillance report by the NICD, JN.1 is the current dominant strain of Covid-19 in South Africa.
JN.1 is a subvariant of Omicron that was first identified in the US in September 2023. While it is distinct due to some mutations on the spike protein, there is no clinical evidence that it causes more severe diseases than other subvariants of Omicron.
Can you get the flu and Covid at the same time?
Yes, although this is uncommon, Moyes said.
How can your flu help others?
The NICD is inviting eligible community members to join its respiratory health survey.
The online survey developed by the NICD is known as CoughWatchSA and aims to monitor respiratory symptoms for influenza-like illness.
CoughWatchSA will ask people to report their respiratory symptoms (or lack of symptoms) on a weekly basis for six months during the influenza season. The NICD will use this data to monitor trends in respiratory illness.
CoughWatchSA needs eligible participants to join a home-based testing study, CoughCheck. This study will ask participants to take a nasal swab in their homes for a laboratory confirmation for flu, respiratory syncytial virus or Covid.
This service is only available in Johannesburg, Durban and Cape Town and there are no cost implications. Participants can also register for WhatsApp notifications to fill in the survey. DM
