Current COVID-19 situation in children: 2025 statement

Introduction

By May 2023, WHO declared that COVID-19 was no longer a public health emergency of international concern.  The SARS-CoV-2 virus that causes the COVID-19 pandemic, change over time. Most changes have some effect on the virus behavior. Some changes may affect the virus's properties, such as how easily it spreads, the resulting disease severity, the effect of vaccines, response to medications, diagnostic tests, or other social and public health measures. [1]

WHO continues to monitor SARS-CoV-2 variants, to track changes in viral characteristics and prevalence. The limitations of current COVID-19 surveillance include differences in sequencing and sampling strategies between countries, changes in sampling methods over time, decreasing number of performed tests and delays in sequencing results shared by countries. [2].

Epidemiology of the new COVID variant

By the end of 2024, WHO monitored seven SARS-CoV-2 variants, including two variants of interest (VOIs) BA.2.86 and JN.1, and seven variants under monitoring (VUMs). JN.1 is still the most reported variant globally, accounting for 12.2% of sequences in 41st week of the year. KP.3.1.1 and XEC (both VUMs) show rising prevalence, while all remaining VUMs are declining.

XEC is currently the only SARS-CoV-2 (VUM) with increasing prevalence globally. XEC was first reported in early August 2024 in Germany and a few other European countries but has since continued to spread, with cases identified in 27 countries across Europe, North America and Asia. [2] With significant rise in prevalence between epidemiological weeks 44 and 47, i.e. an increase from 14.3% to 35.6% for the Western Pacific region (WPR), from 37.0% to 48.0% for the European region (EUR), and from 22.7% to 32.8% for the region of the Americas (AMR). There are only four XEC sequences each from the African Region (AFR) and the East Mediterranean Region (EMR), and seventeen sequences from the Southeast Asia region as per WHO initial risk evaluation of XEC, 09 December 2024 [3]. Reports of new variants cases come mainly from countries that test more COVID samples through national surveillance programs. Higher numbers are expected in countries that don't routinely sequence COVID-19 samples.

XEC is considered a recombinant strain resulting when one individual is infected with two different strains of pre-existing COVID subvariants; the merger and rearrangement of Omicron sub lineages KP.3.3 (a descendant of the FL i RT variants) and KS.1.1 joins full segments of two genomes into one new genome. [4] (Figure 1).

CDC reported the latest mutations of SARS-CoV-2 — specifically KP.1, KP.2, KP.3, and their sub-lineages as the most infections in the United States in the first week of August 2024. [4-6]. As of January 11, 2025, Currently, the dominant variant nationwide is XEC, with 47% of cases, followed by LP.8.1, with 15% of cases, and KP.3.1.1, with 14% of cases. The original omicron variant is gone. [7] (Figure 2 (

Clinical Presentation

No reported studies comparing children and adolescents infected with SARS-CoV-2 to adults infected with the same variant, or even the difference between pediatric age groups. Generally speaking, children and adolescents mostly experience mild disease when infected with a SARS-CoV-2 VOC. [9].

Omicron and its subvariants have generally caused milder clinical severity of the disease than that caused by earlier strains in the pandemic, such as Alpha and Delta. The new strains differ in increased transmissibility which is considered a change in virus behavior and may be related to key differences in spike protein sequence that may reduce the effectiveness of some treatments or increase the virus's ability to spread [4], in addition to the waning immunity from previous vaccinations and infections may explain the recent previous summer COVID-19 surge.

According to the CDC, Symptoms may appear 2-14 days after exposure to the virus, may start as mild, and some people will progress to more severe symptoms.

The most common COVID symptoms haven't changed much since the start of the pandemic, they still include (but are not limited to) dry cough, fever or chills, dyspnea, diarrhea, nasal congestion or rhinorrhea and less frequent loss of taste or smell.

Symptoms also commonly include fatigue, muscle or body aches, and headache. The headaches caused by the coronavirus differ from "typical" headaches in that they tend to be longer in duration and more painful, and they may not respond to over-the-counter medications such as aspirin with more chance to develop neurological symptoms as part of the "long-term effects" of infection.

Hoarse voice and sore throat were among the top omicron variant symptoms. Although a runny nose and sneezing were previously considered unrelated to the coronavirus, they are now predominant symptoms with resultant cough from the post-nasal drip.

vaccinated people may experience more sinus and nasal symptoms of the coronavirus than non-vaccinated. Nasal congestion and sneezing may be more common with the omicron subvariant, like XEC than previous variants such as delta. That's because omicron variants tend to inhabit the upper respiratory tract—the nose, mouth, and throat—while former strains were more likely to migrate down the respiratory tract into the lungs.

Some patients may develop conjunctivitis or gastrointestinal symptoms like nausea, vomiting and diarrhea, constipation, abdominal pain and bloating but those symptoms are less common [10].

The biggest change is that affected cases can be asymptomatic or having milder symptoms overall. On the other hand, those at-risk patients are still getting seriously ill with COVID-19 and dying from the virus, they include those who are very young or very old, those who are immunocompromised, with underlying lung conditions or previous organ damage [11].

Immunity from previous infection can have a large protective role against Omicron sub-lineages in countries with low vaccination rates. However, the advantage of past infection may be demoted by emerging new antigenically different sub-lineages with more ability for immune elusion, especially with declining of immunity over time [12].

COVID-19 is considered mild when there are manifestations of upper respiratory tract involvement without evidence of pulmonary or other organs involvement. Moderate COVID-19 is lung involvement without hypoxia. Fortunately, most mild to moderate cases improve with supportive care [13].

Flu and COVID-19

It is not easy to make clinical differentiation between flu and COVID-19 because many of the signs and symptoms are similar ranging from being asymptomatic to severe disease [14]. Swab for influenza A & B may help in early differentiation. Main clinical differences are listed in table (1).

Prevention

The best way to prevent new variants is to slow the spread of the virus. The proven public health strategies used during 2020 pandemic continue to work against new variants as well. Choosing outdoor activities over indoor activities whenever possible, hand washing, keeping safe distance when contact with others, wearing a mask in public places and staying home when sick or having symptoms of COVID-19, in addition to the vaccine when indicated [5].

Diagnosis

New important concerns in diagnosis are three points

Molecular test (ideally nasopharyngeal or nasal swabs):  It is the preferred test to detect viral RNA by PCR. it must include the current mutation sequences.

It provides the most sensitive and specific means of confirming a clinical diagnosis but, it is expensive; requires specialized skills and laboratories and the results can take longer than 24–48 hours to appear [15].

Assessment of the antibody response to SARS-CoV-2 should complement the RNA-based PCR tests and improve the understanding of the disease course, play a role in epidemiological studies and guide vaccine development [16].

Table (1): Main differences between Flu and COVID-19