Covid-19 resurgence: What is JN.1 strain and where is it active?

The JN.1 strain of Covid-19 is spreading through South-east Asia, with health authorities in Hong Kong, Singapore, China and Thailand urging people to get new booster vaccinations.

Here’s everything we know about this strain of Covid that is considered more contagious than other variants:

Most affected countries

The virus is considered active in Hong Kong, with the city state reporting 31 severe cases in the first week of this month.

In Singapore, the Health Ministry said the number of Covid cases jumped 28 per cent to 14,200 in the week ending May 3, with the number of people being admitted to hospital rising by about 30 per cent.

The picture is similar in Thailand, where Covid cases reached 33,030 last week, doubling from the 16,000 cases reported the week previously.

Covid cases are also rising in China, with positivity rates among outpatient and emergency flu-like cases increasing from 7.5 per cent to 16.2 per cent since March, the Centre for Disease Control and Prevention said.

What is the JN.1 Covid variant?

The JN.1 Covid variant is a descendant of the BA. 2.86 strain that carries more than 30 mutations in the spike protein.

“Covid is with us permanently and we have to be vigilant about new strains like JN.1, a sub-lineage of BA. 2.86 Omicron, that appears correlated with increase in hospitalisation for respiratory illness,” Ramanan Laxminarayan, president of health research organisation One Health Trust, previously told The National.

The World Health Organisation (WHO) has designated JN.1 as "variant of interest", though not yet a "variant of concern."

What does 'variant of interest' mean?

The WHO’s definition states that a variant of interest has “genetic changes that are predicted or known to affect virus characteristics such as transmissibility, virulence, antibody evasion, susceptibility to therapeutics and detectability”.

So JN.1 is more contagious than other Covid strains at this time.

It is also “identified to have a growth advantage over other circulating strains in more than one WHO region with increasing relative prevalence alongside increasing number of cases over time, or other apparent epidemiological impacts to suggest an emerging risk to global public health”.

How was it detected and what is the threat level?

The first case of JN.1 was recorded in the US in September 2023.

JN.1 has not shown any signs of greater severity than other Covid strains but it is more contagious.

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