H5N1

WHO: Weekly epidemiological update on COVID-19 - 20 July 2023

WHO has published Weekly epidemiological update on COVID-19 - 20 July 2023. Click or tap through to download the complete report. The overview:

Globally, over 836 000 new COVID-19 cases and over 4500 deaths were reported in the last 28 days (19 June to 16 July 2023). While five WHO regions have reported decreases in the number of both cases and deaths, the Western Pacific Region has reported a decline in cases but an increase in deaths. 

As of 16 July 2023, over 768 million confirmed cases and over 6.9 million deaths have been reported globally. Currently, reported cases do not accurately represent infection rates due to the reduction in testing and reporting globally. 

During this 28-day period, 56% (131 of 234) of countries and territories reported at least one case – a proportion that has been declining since mid-2022.

WHO: Dengue – the Region of the Americas

A WHO DON: Dengue – the Region of the Americas. Excerpt:

Situation at a glance  

Since the beginning of 2023, dengue outbreaks of significant magnitude have been recorded in the WHO Region of the Americas, with close to three million suspected and confirmed cases of dengue reported so far this year, surpassing the 2.8 million cases of dengue registered for the entire year of 2022. Of the total number of dengue cases reported until 1 July 2023 (2 997 097 cases), 45% were laboratory confirmed, and 0.13% were classified as severe dengue. The highest number of dengue cases to date in 2023 are in Brazil, Peru, and Bolivia. Additionally, 1302 deaths were reported in the Region with a Case Fatality Rate (CFR) of 0.04%, in the same period.  

As part of the implementation of the Integrated Management Strategy for the Prevention and Control of Arboviral Diseases (IMS-Arbovirus), WHO is actively working with the Member States to strengthen healthcare and surveillance capacity.  

WHO has assessed the risk of dengue as high at the regional level due to the wide spread distribution of the Aedes spp. mosquitoes (especially Aedes aegypti), the continued risk of severe disease and death, and the expansion out of historical areas of transmission, where all the population, including risk groups and healthcare workers, may not be aware of warning signs.  

WHO does not recommend any travel and/or trade restrictions for countries in the Americas experiencing the current dengue epidemics based on the currently available information.  

Description of the situation  

Dengue is the arbovirus that causes the highest number of cases in the Region of the Americas, with epidemics occurring cyclically every 3 to 5 years. During the first half of 2023, dengue outbreaks of significant magnitude were recorded in South America.  Between epidemiological week (EW) 1 and EW 26 of 2023 (week ending on 01 July), a total of 2 997 097 cases of dengue were reported in the Region of the Americas, including 1302 deaths with a CFR of 0.04%, with a cumulative incidence rate of 305 cases per 100 000 population. Of the total number of dengue cases until EW 26 of 2023, 1 348 234 (45%) were laboratory confirmed, and 3907 (0.13%) were classified as severe dengue.  

The highest number of dengue cases was observed in Brazil, with 2 376 522 cases, followed by Peru with 188 326 cases, and Bolivia with 133 779 cases.  

The highest cumulative incidence rates were observed in the following subregions: the Southern Cone with 862 cases per 100 000 inhabitants, the Andean Subregion3 with 268 cases per 100 000 inhabitants, and the Central American Isthmus and Mexico4 with 59 cases per 100 000 inhabitants.  

The highest number of severe dengue cases was observed in the following countries: Brazil with 1249 cases, Peru with 701 cases, Colombia with 683 cases, Bolivia with 591 cases and Mexico with 141 cases.  

All four dengue virus serotypes (DENV1, DENV2, DENV3, and DENV4) are present in the Region of the Americas. In 2023, up to EW 26 (ending on 1 July), simultaneous circulation of all four serotypes has been detected in Brazil, Colombia, Costa Rica, Guatemala, Honduras, Mexico, and Venezuela; while in Argentina, Panama, Peru, and Puerto Rico, DENV1, DENV2 and DENV3 serotypes circulate, and in Nicaragua the serotypes DENV1, DENV3 and DENV4.  

In 2022, 2 811 433 dengue cases were reported in the Region of the Americas, the third highest year on record, only surpassed by 2016 and 2019. In 2019, the highest number of historical dengue cases was registered, with more than 3.1 million cases for the Region of the Americas, including 28 203 severe cases and 1823 deaths.

Official data hinted at China’s hidden Covid toll. Then it vanished.

Via The New York Times: Official Data Hinted at China’s Hidden Covid Toll. Then it Vanished. Excerpt:

Official data from China offered a rare, but brief, glimpse of the true toll of Covid, indicating that nearly as many people may have died from the virus in a single province earlier this year as Beijing has said died in the mainland during the entire pandemic.  

The data was deleted from a provincial government website just days after it was published on Thursday. But epidemiologists who reviewed a cached version of the information said it was the latest indication that the country’s official tally is a vast undercount.  

The number of cremations in the eastern province of Zhejiang rose to 171,000 in the first quarter of this year, the website said. That was 72,000 more cremations, a roughly 70 percent increase, than had been reported in the same period last year.  

In February, China said the official death toll in the mainland since the start of the pandemic was 83,150 — a remarkably low number that independent researchers have said is not credible. Since then, the government has released only weekly or monthly death tolls that, when added up, raise the overall total to about 83,700.

Covid surged across China late last year, forcing the government to abandon its strict pandemic restrictions in December. The government’s abrupt policy reversal, however, left hospitals and pharmacies unprepared for the onslaught and likely accelerated the spread of infections and a wave of deaths across the country.  

That surge of Covid infections across China lasted for about two months. The majority of the deaths occurred in January, but many people died in December as well. Epidemiologists estimate that 80 to 90 percent of the population was infected.  

The Zhejiang data offered a window into cremation figures that have been closely guarded by the Chinese government. While the data does not include the cause of death, researchers regularly use excess death statistics to estimate the impact of major deadly events like disasters and pandemics. Everybody who dies in Zhejiang is cremated, officials say.  

Many local and national authorities have withheld regularly published cremation data since that first major Covid wave started late last year. It is unclear why Zhejiang Province published data for the first quarter of this year, but three days after it surfaced, the report was removed.  

Calls on Tuesday to multiple numbers at Zhejiang’s civil affairs bureau went unanswered. The Beijing-based media outlet Caixin reported on the figures Monday, but its article was also quickly taken down.

An analysis by The New York Times published in February estimated that China’s recent Covid wave may have killed between a million and 1.5 million people, based on research from four teams of epidemiologists.  

The new data from Zhejiang — which is limited to a province of 65.8 million people — when extrapolated to the country’s population of 1.4 billion people, is roughly consistent with that range, experts from two of those teams said.

WHO: Influenza A(H5N1) in cats – Poland

A WHO DON, published July 16: Influenza A(H5N1) in cats – Poland. Excerpt:

Situation at a glance 

On 27 June 2023, the IHR National Focal Point of Poland notified WHO of unusual deaths in cats across the country. As of 11 July, 47 samples have been tested from 46 cats and one captive caracal, of which 29 were found to be positive for influenza A (H5N1). Fourteen cats are reported to have been euthanized, and a further 11 died, with the last death reported on 30 June. The source of the exposure of cats to the virus is currently unknown and epizootic investigations are ongoing.  

Sporadic infection of cats with A(H5N1) has previously been reported, but this is the first report of a high numbers of infected cats over a wide geographical area within a country.  

As of 12 July, no human contacts of A(H5N1) positive cats have reported symptoms, and the surveillance period for all contacts is now complete.  

The risk of human infections following exposure to infected cats at the national level is assessed as low for the general population, and low to moderate for cat owners and those occupationally exposed to H5N1-infected cats (such as veterinarians) without the use of appropriate personal protective equipment.  

WHO continues to monitor the situation and work in close collaboration with the animal and public health sectors, regional agencies, the Food and Agriculture Organization of the United Nations (FAO), the World Organisation for Animal Health (WOAH), and other partner agencies in Poland.  

Description of situation  

On 27 June 2023, the IHR National Focal Point of Poland notified WHO of unusual deaths in cats across the country. As of 11 July 2023, a total of 47 samples have been tested from 46 cats and one caracal (Caracal caracal). Of these 47 samples, 29 (62%) were positive for influenza A(H5N1). Positive samples were reported from 13 geographical areas within the country.  

Some cats developed severe symptoms including difficulty in breathing, bloody diarrhoea, and neurological signs, with rapid deterioration and death in some cases. In total, 20 cats had neurological signs, 19 had respiratory signs, and 17 had both neurological and respiratory signs.   

Fourteen cats are reported to have been euthanized, and a further 11 died.  Post-mortem exams on a small number of cats are suggestive of pneumonia. According to the information available, the last known death among cats was reported on 30 June.      

Genomic analysis of 19 viruses sequenced from this outbreak showed that they all belonged to the H5 clade 2.3.4.4b and were highly related to each other. Also, the viruses are similar to influenza A(H5N1) clade 2.3.4.4b viruses which have been circulating in wild birds and which caused outbreaks in poultry recently in Poland.   

The source of exposure of cats to the virus is currently unknown and epizootic investigations are ongoing. There are several possibilities for the source of infection, among which the cats could have had direct or indirect contact with infected birds or their environments, ate infected birds, or ate food contaminated with the virus. Authorities are investigating all potential sources and to date have not ruled out any. Of the 25 cats for which the information is available, two were outdoor cats, 18 were indoor with access to a balcony, terrace, or backyard, and five were indoor cats with no access to the outside environment. Seven cats are reported to have had the opportunity for contact with wild birds.   

This is the first report of high numbers of cats infected with avian influenza A(H5N1) spread over a wide geographical area within any country.  Sporadic infections in domestic cats with A(H5N1) viruses, including A(H5N1) H5 clade 2.3.4.4b viruses, have been reported previously, following close contact of the cats with infected birds or from ingesting meat of infected birds.

Multiomic characterisation of the long-term sequelae of SARS survivors: A clinical observational study

Thanks to @OmegaMom for providing the link to this February report in eClinicalMedicine: Multiomic characterisation of the long-term sequelae of SARS survivors: a clinical observational study. SARS affected far fewer people than COVID-19, but survivors were very much at risk of long SARS. The summary:

Background  

We aimed to characterise the long-term health outcomes of survivors of severe acute respiratory syndrome (SARS) and determine their recovery status and possible immunological basis.  

Methods  

We performed a clinical observational study on 14 health workers who survived SARS coronavirus infection between Apr 20, 2003 and Jun 6, 2003 in Haihe Hospital (Tianjin, China). Eighteen years after discharge, SARS survivors were interviewed using questionnaires on symptoms and quality of life, and received physical examination, laboratory tests, pulmonary function tests, arterial blood gas analysis, and chest imaging. Plasma samples were collected for metabolomic, proteomic, and single-cell transcriptomic analyses. The health outcomes were compared 18 and 12 years after discharge. Control individuals were also health workers from the same hospital but did not infect with SARS coronavirus.  

Findings  

Fatigue was the most common symptom in SARS survivors 18 years after discharge, with osteoporosis and necrosis of the femoral head being the main sequelae. The respiratory function and hip function scores of the SARS survivors were significantly lower than those of the controls. Physical and social functioning at 18 years was improved compared to that after 12 years but still worse than the controls. Emotional and mental health were fully recovered.  

Lung lesions on CT scans remained consistent at 18 years, especially in the right upper lobe and left lower lobe lesions. Plasma multiomics analysis indicated an abnormal metabolism of amino acids and lipids, promoted host defense immune responses to bacteria and external stimuli, B-cell activation, and enhanced cytotoxicity of CD8+ T cells but impaired antigen presentation capacity of CD4+ T cells.  

Interpretation  

Although health outcomes continued to improve, our study suggested that SARS survivors still suffered from physical fatigue, osteoporosis, and necrosis of the femoral head 18 years after discharge, possibly related to plasma metabolic disorders and immunological alterations.