Cicada — a new variant of Covid-19: is there reason for concern for us in Latvia? 0 8

Cases of infection with the Cicada strain, officially named BA.3.2, have already been reported in the USA, Hong Kong, Mozambique, and the UK.

And although there is no reason to believe that this strain is more dangerous than others, experts note that children seem to be infected more often than adults.

So should we be worried?

What is known about Cicada?

The BA.3.2 strain was named "Cicada" because after its discovery, it remained in a state of "hibernation" in some parts of the world — similar to this insect, known for being able to sleep in the ground for a long time.

Last month, the American government agency — the Centers for Disease Control and Prevention (CDC) — reported cases of illness in 25 states.

The report states that the BA.3.2 strain was found in nasal swabs from four travelers, in clinical samples from five patients, and in 132 wastewater samples.

The WHO has also placed this strain in the "under observation" category, which, according to them, means that it "may require increased attention," and specialists are currently determining whether it poses a threat to global health.

An analysis of disease data in New York conducted by researcher of various Covid strains Ryan Hisner suggests that children are more likely to test positive for BA.3.2 than adults.

"This has not undergone peer review and has not been published, but it seems to be true," says Professor Ravindra Gupta from the Cambridge Institute of Therapeutic Immunology and Infectious Diseases.

There are various theories as to why this is happening. One is that the immune system of any person has difficulty recognizing Cicada, as it is a strain we have not encountered before.

"Children generally have weaker immunity than adults because they have not been exposed to as many different viruses and Covid infections, so it can be expected that their immunity to this virus will be quite weak," says Gupta.

In adults, the glands that produce antibodies to protect against viruses develop over many years and help strengthen immunity.

"Children have had much less time to go through this immune development process, and this may partially explain why they are more susceptible to this virus," he adds.

Other researchers have suggested that the cases of infection in children may be due to a heavily mutated protein of the Cicada strain.

Gupta and his team are searching for samples taken from children to conduct further studies and determine why this variant seems to affect them more.

How do the symptoms manifest?

At this point, there is no data indicating that Cicada causes more severe forms of illness in people than other variants of the Covid-19 virus.

"There are also no specific symptoms that occur more frequently," adds Professor Paul Hunter, an epidemiologist at the University of East Anglia in the UK.

Covid-19 is accompanied by symptoms such as fever, cough, sore throat, nasal congestion, fatigue, headaches, body aches, shortness of breath, and diarrhea.

"The virus targets the same cells regardless of the strain... so the symptoms you experience remain more or less the same," explains Ian Jones, a virologist at the University of Reading in the UK.

Why has this variant mutated so much?

All viruses mutate over time, and RNA viruses like Covid-19 mutate particularly quickly.

The CDC characterized the BA.3.2 strain as "highly divergent." This means it is significantly different from the original Omicron strain.

According to Jones, these mutations may hinder the immune system's ability to recognize the virus and to some extent allow it to evade the immunity that has already developed.

"The virus is clearly succeeding: it is evading antibodies in people's bodies, and therefore the number of cases is gradually increasing," he adds.

Will the vaccine still work?

Due to these mutations, Covid-19 vaccines may be less effective in protecting against the Cicada strain. Nevertheless, experts insist that existing vaccines still provide some protection against this variant.

"You may get infected, but the illness will be mild," explains Jones.

According to the WHO, as of today, 67% of the total population has been vaccinated against Covid-19.

However, access to updated booster vaccines specifically designed to protect against new strains depends on the region.

Jones explains that pharmaceutical companies will develop a new version of the vaccine specifically targeting Cicada only if the number of infections and the severity of the disease increase sharply.

Should we be worried?

Epidemiologist Hunter says that there is nothing surprising about the fact that we continue to encounter new variants of the Covid-19 virus.

"We will see new strains of the virus emerge as long as there are people living on the planet. It is doubtful that SARS-CoV-2 will ever disappear," he adds.

He notes that the increase in cases of the Cicada strain does not necessarily mean that the overall number of Covid-19 cases or deaths from it will also increase.

"New strains will emerge regularly and contribute to new waves of illness... but it is likely that we will continue to see a decrease in deaths and severe cases," he adds.

In December, the WHO stated that there is no data indicating an increase in severe cases of illness, hospitalizations, or deaths related to Cicada, and noted that the new strain poses a low risk to public health.

"[Covid-19] has now become one of the common winter respiratory infections, and people just need to keep that in mind," says Jones. "If they believe that the vaccine will benefit them, they should go and get vaccinated."

However, representatives of at-risk groups — including people over 65, those with weakened immune systems, and those with chronic illnesses — may experience severe illness from COVID-19.

"It is important to seek medical attention promptly if your child already has lung, heart, or immune deficiency conditions," says Gupta. "But for most healthy children, the illness should resolve on its own," explains the BBC.

Now we await clarifications from Latvian epidemiologists...