Covid 19 Resources Center

Further infections with H5N1 avian influenza virus continue to be reported in various mammals, including marine mammals in US and UK. Although only a few isolated cases have occurred in humans (through contact with birds), the mammalian infections are being watched closely.

COVID-19 rates continue to be a mixed picture, rising recently in some areas while falling in other regions. Several countries have announced the end of pre-travel COVID-19 testing requirements for travellers from China, including USA, Canada, UK, Japan and Australia. Just over half of global sequences of SARS-CoV-2 are the XBB.1.5 subvariant, while XBB.1.9.1 and XBB.1.9.2 currently make up around 12%. There are some further subvariants (EG.1, XBB.1.16, and XBL) whose significance is not yet clear due to low prevalence so far.

Mpox update fronm WHO is available at https://www.who.int/publications/m/item/multi-country-outbreak-of-mpox--external-situation-report---17---2-march-2023 Since 16 February 2023, there have been just 323 new mpox cases (0.4% increase in total cases) and 11 new related deaths. The latest epidemiological data suggests the outbreak is heading towards an end in the European Region, and slowing down in the Region of the Americas where human-to-human transmission occurs.

Local sources reported another death from Nipah virus in Bangladesh, two weeks after a family member died.

Infectious Diseases

Note that norovirus infections are 66% higher in UK than usual for this time of year according to national surveillance data.  Always a risk of on-board infection.   Some notes on norovirus from “YLE-Your Local Epidemiologist” are here:

1. Norovirus is very infectious. On average, one infected person will infect 2-7 other people…it can live on surfaces for weeks. It’s spread through the fecal to oral route so transmission avenues include: 

• Direct contact.6 in 10 infections are through direct contact, like shaking hands or touching door handles, and then putting your hand in your mouth. 
• Indirectly, like through foods. An infected person can touch food with bare hands that have viral particles on them. You can ingest the food and then get sick.
• Aerosolized. If someone throws up in a toilet, for example, viral particles can become aerosoled after flushing. This isn’t the main route of transmission. 
  
  Three out of four norovirus outbreaks occur in nursing homes. Restaurants and schools follow. Cruise ship outbreaks usually make the news, but only account for 1% of outbreaks.

2. People only need a few viral particles to get sick. Once the virus enters the body, norovirus hijacks your cells and turns them into viral factories. It latches on, specifically, to cells in your gut causing less than wonderful symptoms. Before 2018, we didn’t know why norovirus chose the gut, but a new study found it’s because our gut is home to one rare type of cell (tuft cells). 

3. Third, this virus spreads pre-symptomatically and up to 2 weeks after symptoms resolve. In other words, you can spread it even if you don’t have symptoms. 

In Equatorial Guinea an haemorrhagic fever now confirmed to be Marburg virus has caused at least nine deaths.

Two suspected cases in neighbouring Cameroon proved in fact to be malaria (GPHiN).

Bangladesh has reported 11 cases of Nipah virus and eight associated deaths. This is the largest number of cases since 2015 when 15 cases were reported. The outbreak risk is considered high locally.

COVID-19 Cases and deaths continue falling in China; it is estimated that there are currently ~1.64 million cases per day, ~61% lower than the peak, and ~12,600 deaths per day, 64% lower than peak deaths.  The EU has announced the end to its recommendation for pre-departure testing of travellers from China (Airfinity).

COVID-19 cases are increasing across Europe as well as in North America, Russia, and Indonesia. 

In terms of variants, it is suggested that XBB.1.9.1 is one to watch, growing more rapidly than even XBB.1.5, and circulating widely in Southern Asia and Europe - but still a very low percentage of sequences globally.  (Airfinity). 

The WHO Emergency Committee on COVID-19 met last week and on its advice, WHO’s Director-General extended the PHEIC designation but signposted clearly its possible lifting/termination in three months.  Please find below the link to the statement of the Emergency Committee:  https://www.who.int/news/item/30-01-2023-statement-on-the-fourteenth-meeting-of-the-international-health-regulations-(2005)-emergency-committee-regarding-the-coronavirus-disease-(covid-19)-pandemic.    Some background to the decision is outlined in Nature here:  https://www.nature.com/articles/d41586-023-00294-9    Meanwhile the US has announced the end of COVID-19 emergency declarations (national emergency and public health emergency) in May. 

BlueDot discussed the situation in China recently and pointed to concerns based on three factors:  lack of reliable data on cases, deaths and variants;  insufficient population-level immunity (due to strict lockdowns, low vaccine uptake and somewhat less effective vaccines); and currently increased international travel in the next month (Lunar New Year is the largest annual travel period) leading to increased importation and exportation of variants.

On COVID-19 in China, Airfinity reports forecasting under two scenarios, one of them incorporating media/anecdotal reports of provinces where case rates may have already peaked, in which cases deaths may soon peak.  Sequencing of cases within China and in overseas travellers from China continue to point to variants which are widespread and not of high immune evasiveness.  The WHO Emergency Committee on COVID-19 meets again later this week, on 27 January. 

The possibility of a large-scale COVID-19 rebound in China over the next few months is remote as 80% of the country’s population has been infected, Al Jazeera quoted Wu Zunyou (chief epidemiologist at the China Center for Disease Control and Prevention) as saying last Saturday.  In keeping with this, a Hong Kong University study estimated that 90% of the 22 million population of Beijing will have been infected by the end of January. 

For your reference, from UNWTO and IATA, here is an on-line tool to track travel restrictions including those relating to travellers from China:   https://www.unwto.org/tourism-data/unwto-iata-destination-tracker-easy-travel

COVID-19 continues to spread in China, Airfinity reported, with forecasts showing ~3.6 million new cases per day. Cases are high but appear to be stabilising in Canada and the USA, with deaths still rising, while the case rebound continues in Japan and Australia.   Meanwhile an article in Nature quotes modelling from the UK, suggesting that Chinese outbreak peaked in December, and this is matched by recent claims from Chinese health officials – although not all modellers agree.  https://www.nature.com/articles/d41586-023-00075-4

According to Airfinity, COVID-19 cases in Japan are expected to increase further following a brief decline at the start of the month and are also increasing in Australia, Canada and Mexico while showing signs of stabilising in the USA despite XBB.1.5 spread.