From Airfinity’s curated analysis of various health and media sources, the US CDC, and the ECDC (European Centre for Disease Prevention and Control) Weekly Communicable Disease Threats Report:
- H5N1 infections have now been reported in a total of 185 dairy herds across 13 US states. Colorado is the first state to mandate weekly bulk tank milk testing.
- 25 human H5N1 cases have been detected globally: US (13), Cambodia (9), Vietnam (2), and Australia (1). There is a possible instance of human-to-human transmission in Texas, but outside the US all cases were most likely transmitted from bird to human.
- The US CDC have recommended that children under five, adults 65 years and older, and others at a higher risk of developing serious flu complications, should try and limit contact with animals that could carry influenza viruses at upcoming county fairs. Specific recommendations for fair exhibitors have been issued including reducing the time pigs, poultry, and cattle are on display to not more than 72 hours.
- There currently are several H5N1 vaccine pipeline candidates, eight of which mRNA-based. Meanwhile the US CDC have announced they will offer seasonal influenza vaccines to farmworkers.
- According to the CDC, Colorado has reported the first US case of influenza A(H3N2) variant (v) virus infection in 2024 in a person who attended an agricultural event. The person recovered without hospitalization. When an influenza virus that normally spreads in swine but not people is found in a person it is called a variant influenza virus. No additional cases or person-to-person spread have been identified. Since 2005, 517 variant influenza virus infections have been reported in the US, generally linked to pig exposure.
- COVID-19: Indicators of increased SARS-CoV-2 activity in healthcare settings have been observed in Europe since late spring. The overall impact on hospitals and mortality has been relatively low. Variant BA.2.86 and its subvariants, including KP.3, continue to dominate and are not expected to be associated with increased infection severity or to significantly reduce vaccine effectiveness.
- France has reported the first case of autochthonous chikungunya since 2017. The case was reported in the Greater Paris region and is also the first in the whole of EU/EEA since 2017. Previously, between 2010 and 2017, France had had 31 locally transmitted cases of chikungunya. In the Indian state of Tamil Nadu there is an ongoing surge of chikungunya infections, with over three hundred confirmed cases so far this year.
- Malaria has reemerged as a significant issue in Kokrajhar, Chirang, and Udalguri, three districts in Assam, India.
- Nigeria has reported almost five thousand cholera cases since the beginning of the year. Lagos state accounts for 65% of all suspected cases in the country.
A selection of articles of interest:
- WHO position paper on dengue vaccines
Below are some highlights of possible relevance for aviation. I would tend to conclude that the highest benefit with the lowest risk may be for travellers with demonstrated previous dengue infection and who are travelling to a region with an ongoing epidemic of serotypes DENV2 or DENV1, especially where mosquito eviction is less reliable.
- Persons living in non-endemic countries who have previously been infected with any of the 4 dengue virus serotypes following travel to dengue-endemic countries, may benefit from TAK-003 vaccination to prevent a second (and hence potentially more severe) dengue infection when travelling again to an endemic country.
- Protection starts 14 days after the first dose and has been demonstrated between the first and second dose. To ensure the durability of protection, a second dose is needed after a minimum interval of 3 months.
- Travellers who choose to be vaccinated need to be informed that:
- transmission of dengue is heterogeneous within countries and the circulating serotypes may vary during different periods;
- the vaccine may not confer protection against DENV3 and DENV4 if they are seronegative;
- there is actually a potential risk of severe dengue if seronegative individuals are exposed to DENV3 and DENV4.
- WHO priority pathogens
According to an updated Pathogens Prioritization list just published by the WHO https://www.who.int/publications/m/item/pathogens-prioritization-a-scientific-framework-for-epidemic-and-pandemic-research-preparedness there are now more than thirty pathogens that could cause the next global public-health emergency, such as a pandemic. The list includes the likes of influenza A virus (including subtype H5), coronaviruses, dengue virus and monkeypox virus. This list of ‘priority pathogens’ will hopefully help organizations to decide where to focus their efforts in developing treatments, vaccines and diagnostics. One researcher however reminds us that “some pathogens from the list may never cause an epidemic, and one we have not thought of may be important in the future.” https://www.nature.com/articles/d41586-024-02513-3?WT.ec_id=NATURE-202408&sap-outbound-id=5B694315BB09CA1DF92879B1816A4DB0379B6CB8
Events:
- ICAM 2024: www.icam2024.com
- Aviation Health Conference – early bird until 7th September: https://quaynote.com/conference/aviation-health-conference-24/
Dr Rui Pombal
IATA Medical Advisor