Preparing for a ‘double epidemic’ of COVID-19 and influenza

DUBAI: There’s good news on the flu virus. This year, its global circulation will be much lower, say experts.

The bad news: COVID-19 is still very much around, warns the World Health Organisation (WHO).

The lower circulation of the virus could be attributed to the mandatory physical distancing and hygiene protocols being observed across the world, say experts.

With remote work and schooling becoming part of the new normal amidst the SARS-CoV-2 contagion, seasonal flu is expected to reduce viral transmission as well.

But with over 27.6 million cases and nearly 900,000 deaths worldwide caused by COVID-19, the onset of the flu season could be a “cause of concern”, says the world health body.

Flu season, with COVID-19

And while the low-circulation influenza virus could be a matter of reassurance, it’s also a matter of “concern”, a Lancet article stated this week.

The world, mostly the northern hemisphere, is entering the influenza season (usually from around October to February, but may last till May).

In the UAE, doctors are preparing for the flu season early with a stockpile of vaccine jabs, with some hospitals reportedly buying more than their usual stocks of flu shots.

Doctors said they have begun planning for the flu season, with new batches of influenza vaccines in the pipeline. Once the shots are available, people will be advised to get it.

Due to the risk of COVID-19, doctors advice a flu shot will become more important this year than in the past.

Preparing for a ‘double epidemic’

Meanwhile, experts said it’s important to consider the potential impact of testing and people seeking healthcare services.

“We need to bear in mind that the measures we’re putting in place to control COVID-19 may have some benefits for the flu as well; but with the resurgence of COVID-19 there may also be a double epidemic of flu and COVID-19 during the [northern hemisphere] winter,” said Richard Pebody (WHO Regional Office for Europe, Copenhagen, Denmark).

“All what we can do about it is to be ready and prepared with a range of measures we’ve got in our community ammunition box,” Pebody was quoted by the journal as saying.

Ramping up testing capacity

The Lancet article, published earlier this month, stated that one way to tackle for a possible double epidemic is to ramp up the testing capacity for both COVID-19 and seasonal flu infections.

Greater testing, however, does not discount the benefits of social distancing, proper hygiene and wearing of masks, especially when in public settings – the so-called “non-pharmaceutical interventions” (NPIs).

It cited some best practices adopted by health authorities. For example, the WHO National Influenza Centre at the Westmead Hospital (in New South Wales, Australia), which continued to test for other respiratory viruses throughout the COVID-19 pandemic.

As of June this year, the centre had done twice the number of tests it would have usually.

“What was interesting was that we actually had negligible cases of influenza and respiratory syncytial virus compared to previous seasons,” said Westmead Hospital's Jen Kok was quoted as saying.  “We were doing a lot of testing, but we just weren’t finding any cases whatsoever."

Since New South Wales started recording these infections, detections have been the lowest – despite the increased number of tests.

Would a combined testing for both COVID-19 and influenza work?

Yes, according to experts. The reason is because a single sample could be used to distinguish the two infections in patients presenting with similar symptoms.

In July, the US FDA gave a emergency use authorisation (EUA) for such a combination test – the third EUA issued by the agency.

A UK equivalent of the test is expected to be available in UK National Health Service hospitals from this month (September).

“It would be great if other countries and agencies would pursue developing more combination tests, because assessing for multiple diseases in a single swab can also help reduce the demand for testing supplies and reduce the risk of exposure to health-care workers collecting the sample,” said Nídia Sequeira Trovão (US National Institute of Health, Washington, DC, USA).

Boosting flu vaccination programmes

A European CDC official said one possible strategy to curb the likelihood of a double epidemic would be to strengthen existing flu vaccination programmes.

The Lancet cited Pasi Penttinen (European Centre for Disease Prevention and Control, Stockholm, Sweden) as saying: “We’ve got several questions in the air for what will happen in the next season but having [COVID-19 and influenza] circulate at the same time is really something that you want to avoid as much as possible.”

A key challenge for health authorities, said Penttinen, is how to broaden the flu shot coverage, adding: “For influenza, we’re lucky to have a vaccine. And now, the debate among public health authorities is how to broaden the flu shot target groups from the current consensus.”

Health-care workers at the forefront of COVID-19 care are likely to be mandated for influenza shots.

Benefits of flu shots in children

Vaccination of children is also under consideration. In the 2017–18 influenza season, only six countries in the EU recommended vaccination of children.

Penttinen thinks that “[to vaccinate children or not] is a question that countries should have right now because vaccinating children against influenza reduces their risk of transmission of flu to the elderly and thus protects them better than direct vaccination of the elderly”.

Widening the coverage of influenza shots, however, comes with certain challenges, mostly due to the fact that several countries would have placed an order for the vaccine before the pandemic.

Therefore, increasing the bumping up flu shots demand now could lead to a vaccine shortage, the article stated.

Dilemma

“So countries are faced with a very difficult dilemma here in terms of how much effort to put into the influenza vaccination program in this situation,” Penttinen said.

Experts urged people to adhere to social distancing, wearing masks and observing proper hygiene practices, especially hand-washing.

They cite evidence of the benefits of these non-pharmaceutical interventions and believe that increased preparedness could prevent a serious double epidemic.

Paul Hunter (University of East Anglia, Norwich, UK), stated: “I think the feared double epidemic will probably not happen [since] the continuing social distancing that we are likely to see well into next year should be sufficient to supress any influenza epidemic.”

At the same time, there’s a concern that with very low influenza activity leading to declined herd immunity to influenza, when the world gets back to normal after COVID-19 pandemic.

“It would be a shame if we get through COVID-19 only to be hit harder by influenza the following winter season,” Hunter told the Lancet.

WHO-recommended flu vaccines for 2020-2021 season

Quadrivalent vaccines:

The WHO recommends that quadrivalent vaccines for use in the 2020 - 2021 northern hemisphere influenza season contain the following:

Egg-based Vaccines

Cell- or recombinant-based Vaccines

Trivalent influenza vaccines:

Egg-based Vaccines

Cell- or recombinant-based Vaccines