#Taiwan, #Epidemics of Respiratory Viruses (#COVID19, #Influenza, #Enteroviruses) Weekly Update (CDC, August 25 '26): PQ.16.1.1 Variant Still Predominant

 

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    CDC monitoring data shows that the domestic COVID-19 epidemic is at a plateau. 

    In week 33 (August 16-22), there were 24,995 outpatient and emergency room visits for COVID-19, a 6.0% decrease compared to the previous week (August 9-15). 

    Last week (August 18-24), there were 59 new locally transmitted severe cases and 19 new locally transmitted deaths. 

    Since October 2025, there have been a total of 480 local cases of COVID-19 complicated by severe illness, of which 73 have died. 

    The majority of severe cases are among those aged 65 and above (73.5%) and those with a history of chronic diseases (82.5%). 86.5% of these cases have not been vaccinated this season. 

    In the past four weeks, the predominant variant strain in local cases has been PQ.16.1.1.     

    As of August 24, approximately 1.823 million doses of the COVID-19 vaccine have been administered this season. There are currently about 111,000 doses remaining nationwide, which will be available until September 9. Eligible and needy individuals are advised to take advantage of this time and get vaccinated as soon as possible.

    Regarding the influenza epidemic, in week 33 (August 16-22), there were 94,340 outpatient and emergency room visits for influenza-like illnesses, a slight decrease of 2.5% compared to the previous week. 

    Additionally, last week (August 18-24), there were 64 new cases of severe influenza complications (59 H1N1 and 5 H3N2) and 15 deaths (all H1N1). 

    Laboratory surveillance data shows that the influenza virus currently circulating in the community is predominantly type A, with type A H1N1 accounting for a high percentage at 69.7%. 

    This flu season (2014-2015) saw a cumulative total of 1,139 severe cases (540 H1N1, 491 H3N2, 18 untyped A, and 90 B) and 220 deaths (101 H1N1, 101 H3N2, 6 untyped A, and 12 B). 

    The majority of severe cases were among those aged 65 and over (63.8%) and those with a history of chronic illness (82.4%). 71.0% of patients had not received the flu vaccine this season.

    Regarding enterovirus cases, in week 33 (August 16-22), there were 6,546 outpatient and emergency room visits, similar to the previous week (6,646), indicating a stable recent trend. 

    Laboratory surveillance over the past four weeks showed that Coxsackievirus A6 was the most prevalent enterovirus in the community, followed by enterovirus D68 and Coxsackievirus A16. 

    This year (2026), there have been a total of 6 confirmed cases of enterovirus infection complicated with severe illness (including 1 death), including 4 cases of enterovirus D68, 1 case each of Coxsackievirus A4 and Coxsackievirus A16. 

    Regarding the dengue fever outbreak, as of August 24th this year, there have been a total of 134 confirmed dengue fever cases, including 7 local cases (all residing in Kaohsiung City) and 127 imported cases. The imported cases were mainly from Southeast Asian and South Asian countries such as Indonesia (26 cases), Vietnam (26 cases), and the Maldives (16 cases). The cumulative number of cases is lower than the same period in 2025 (152 cases).

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Source: 

Link: https://www.cdc.gov.tw/Bulletin/Detail/QiAsLBvifNAj7FJzGc-ApQ?typeid=9

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A #clinical #SARS-CoV-2 #Mpro #inhibitor blocks replication of multiple #enteroviruses and confers oral in vivo protection in animal models

 

Abstract

Enteroviruses, which belong to the family Picornaviridae, cause hand, foot, and mouth disease (HFMD), respiratory symptoms, and severe neurological complications in children. Since vaccines cannot provide cross-protection against different serotypes of enteroviruses, the development of broad-spectrum anti-enteroviral drugs is imperative. The viral 3C protease (3Cpro), which is essential for polyprotein processing represents a validated target for therapeutic intervention. Importantly, enterovirus 3Cpro shares conserved structural and catalytic features with coronavirus main protease (Mpro, also known as 3C-like protease, 3CLpro), providing a rationale for cross-target inhibitor repurposing. Through targeted screening of peptidomimetic protease inhibitors, a clinical-stage SARS-CoV-2 Mpro inhibitor was identified as a potent inhibitor of enterovirus A71 (EV71) 3Cpro. Bofutrelvir displayed nanomolar antiviral activity in multiple cell lines and demonstrated broad-spectrum efficacy against several enteroviruses including coxsackievirus B5, coxsackievirus A16 (CA16) and echovirus 11. In EV71 infected neonatal mice, intraperitoneal administration of bofutrelvir markedly reduced viral loads in brain, spinal cord, and muscle, alleviated clinical symptoms, and suppressed tissue inflammation. Oral administration of bofutrelvir also provided therapeutic benefits in neonatal mice models of both EV71 and CA16. Crystallographic analysis revealed that bofutrelvir binds in the conserved substrate-binding cleft of EV71 3Cpro, elucidating its molecular mechanism of inhibition. These findings identify bofutrelvir as a broad-spectrum peptidomimetic 3Cpro inhibitor with strong antiviral efficacy against enteroviruses and highlight its potential for repurposing as a promising antiviral candidate for the treatment of enteroviral infections.

Source: 

Link: https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1014051

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The Emergence of #Coxsackievirus A16 Subgenotype B1c: A Key Driver of the #HFMD #Epidemic in #Guangdong, #China

Abstract

Background: 

In 2024, mainland China witnessed a significant upsurge in Hand, Foot, and Mouth Disease (HFMD) cases. Coxsackievirus A16 (CVA16) is one of the primary causative agents of HFMD. Long-term monitoring of theCVA16 infection rate and genotype changes is crucial for the prevention and control of HFMD. 

Methods: 

A total of 40,673 clinical specimens were collected from suspected HFMD cases in Guangdong province from 2018 to 2024, including rectal swabs (n = 27,954), throat swabs (n = 6791), stool (n = 5923), cerebrospinal fluid (n = 3), and herpes fluid (n = 2). A total of 24,410 samples were detected as EV-positive and further typed by RT-PCR. A total of 872 CVA16-positive samples were isolated and further sequenced to obtain the full-length VP1 sequence. Phylogenetic analysis was performed based on viral protein 1 gene (VP1). 

Results: 

In the first 25 weeks of 2024, reported cases of HFMD were 1.36 times higher than the mean rates of 2023. In 2024, CVA16 predominated at 75.42%, contrasting with the past etiological pattern in which the CVA6 was predominant with the detection rate ranging from 32.85 to 77.61% from 2019 to 2023. Phylogenetic analysis based on the VP1 gene revealed that the B1a and B1b subtypes co-circulated in Guangdong from 2018 to 2022. The B1c outbreak clade, detected in Guangdong in 2023, constituted 68.24% of the 148 strains of CVA16 collected in 2024, suggesting a subtype shift in the CVA16 virus. There were three specific amino acid variations (P3S, I235V, and T240A) in the VP1 sequence of B1c. 

Conclusions: 

The new emergence of the CVA16 B1c outbreak clade in Guangdong during 2023–2024 highlights the necessity for the enhanced surveillance of the virus evolution epidemiological dynamic in this region. Furthermore, it is imperative to closely monitor the etiological pattern changes in Hand, Foot, and Mouth Disease (HFMD) in other regions as well. Such vigilance will be instrumental in guiding future vaccination strategies for HFMD.

Source: Viruses, https://www.mdpi.com/1999-4915/17/2/219

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