Looking ahead to winter and beyond for infections and vaccines.

The latest research and developments on COVID-19, avian-flu and cancer vaccines

A few pre-prints and articles have been out recently that I will quickly summarise and reflect what this may mean for vaccine developments.

Avian Flu

First-up I wanted to reflect on what is happening with avian flu as that has been in the news a lot recently. This is because its has been shown that the virus is transmitting between cows in the USA and traces of viral genetic information has been detected in milk. There is no evidence that the virus is infectious in pasteurised milk as the process of pasteurisation should kill the virus (and studies are ongoing now to confirm this) but certainly raw milk should be avoided. Eric Topol has summarised the situation in the States beautifully so I urge you to read this.

The virus has been decimating populations of wild birds for several years now causing a catastrophic drop in numbers of birds such as gannets. It has also been observed in some animals including seals. This has been suspected to be mostly transmission via the bird to the new host rather than between the new hosts but more detailed analysis has suggested it possible it has spread between other hosts. There have been isolated cases in people but these have been occurring when people have had close contact with birds such as poultry workers. However, given the growing transmission between hosts, more widespread infection in human is something we need to be vigilant about. Given, the situation in the USA, they have rightly stepped up measures and made it clear that they are ready to act with anti-virals stockpiled and potential to gear up vaccine production.

What about the UK?

In the UK, we have had no cow-cow transmission (to my knowledge). The UK-HSA has good surveillance for avian flu viruses in place and several organisation across the world are also monitoring the situation. At this stage we can help by contributing to the data collection. If you see a dead or sick bird do take care with bird carcasses and try to keep pets such as dogs away. Crucially, you should use the reporting system to DEFRA that contributes to our avian flu surveillance. There is good news though as recent evidence suggest some seabird colonies may have developed immunity and we are seeing some signs of recovery in our bird colonies.

COVID-19 update

The virus continues to mutate and there are increases of new subvariants of the current dominant variant JN.1 which have all really taken over the XBB lineages. These subvariants are called the FLiRT group of variants and they represent about 25% of sequenced cases in UK currently and this incidence is growing. It is predicted that these FLiRT subvariants will cause waves and we don’t yet know how serious they will be. A new pre-print from the Cao lab has explored the evolving immune responses to all these COVID-19 variants. I also urge you to look at his threads on social media including X and Mastodon for more info (@yunlong_cao). The take-homes from the data is that the immune responses to XBB and JN.1 infections are distinct (b and c on the figure) in infection naive people (those never vaccinated or infected). There is some overlap but there are unique targets for antibodies to JN.1. All of the four JN.1 subvariants tested in the pre-print showed evidence of immune evasion with KP.3 showing a 1.9 to 2.4-fold reduction in neutralising antibody binding compared to the JN.1 parental strain.

(Image taken from the Cao Pre-print)

Looking ahead

What should we take from this study? The virus is clearly continually adapting and learning ways to escape our immune system. This may mean that prior vaccine and hybrid immunity may have less efficacy against the virus. What this means in terms of infection severity we do not yet know but it emphasises the importance of continued monitoring of the virus. As well as the continued need for studies like Cao’s which start to ask questions about immune responses. This data may suggest that future vaccine targets should focus on JN1.1 not XBB - say for autumn/winter campaigns.

Longer term, multivariant vaccines that have broader specificity and mucosal vaccines that may be sterilising are needed to try and beat the virus at this game of immune cat and mouse. We also need to consider who can access the vaccines with recent data out from ONS showing that cases of Long Covid remains a serious issue and new cases are occurring (do read this excellent summary from Christina Pagel). Reducing the likelihood of infection exposure is also paramount and action to address ventilation is needed.

Some more positive news

Finally to leave you with- a new story on mRNA vaccines and cancer. mRNA technology for vaccines has been a real gamechanger and its looked incredibly promising in cancer treatment with big steps happening with melanoma therapy. The latest work focuses on personalised vaccines. The tumours are removed from a patient, sequenced and analysed to determine key novel antigens and then up to 34 antigens (the targets for the immune system) are used to create a personalised vaccine. The vaccine will then trigger an immune response to a broad range of the person’s own tumour antigens.

A phase 2 trial found that these personalised vaccines dramatically reduced the risk of the cancer returning in melanoma patients. Now a final, phase 3, trial has been launched with the first patients already recruited. This is incredible news and shows just how far we have come in terms of understanding both the immunology of cancers and the potential of mRNA vaccines.

However, any vaccine is only as good as the take up of the vaccine. Disinformation and misinformation about vaccines and particularly mRNA vaccines is rife and this contributes to uncertainty and vaccine hesitancy. We cannot afford to ignore this threat and action is needed to address concerns sensitively as well effectively remove dangerous disinformation and algorithms that enhances its visibility.