Disease outbreaks and other matters of airline medical interest

From Airfinity’s curated analysis of various health and media sources and from the ECDC (European Centre for Disease Prevention and Control) Weekly Communicable Disease Threats Report:

  • H5N1 avian influenza has been detected in poultry farms in more European countries, namely Hungary, Croatia and the Netherlands (see also the previous MCG update).
  • Pakistan has confirmed its fifth wild poliovirus infection in a toddler. This is relevant in that there is an ongoing effort worldwide to completely eradicate polio.  More about the Global Polio Eradication Initiative here: https://polioeradication.org/  A good analogy from not so long ago is the successful eradication of smallpox which was declared in 1980, three years after the last natural case had occurred in Somalia  – more here https://www.cdc.gov/smallpox/history/history.html .
  • Another outbreak of cholera, this time in the Dominican Republic.
  • The US FDA has just approved the world's first chikungunya vaccine.
  • On 23 November 2023, the World Health Organization (WHO) published a Disease Outbreak News (DON) about clusters of undiagnosed pneumonia in school-aged children in the Beijing and Liaoning regions in China.

Chinese authorities responded to WHO’s request to share more data on the current situation of respiratory illnesses in the country. The data shared showed an increase in paediatric hospitalisations due to Mycoplasma pneumoniae since May this year, as well as rising incidence of other common community respiratory viruses since October, namely adenovirus, respiratory syncytial virus (RSV) and influenza. M. pneumoniae meanwhile, seems to be the leading cause of surging paediatric respiratory illness in China. COVID-19 levels have been declining and the rates of infection with adenovirus, and RSV are at lower levels than M. pneumoniae.

According to the ECDC, the Chinese surveillance data has clarified that there has been no detection of any unusual or novel pathogens or unusual clinical presentations.

Increase in respiratory infections in the paediatric population is not unexpected during the Winter months in temperate regions of the world, due to several seasonal pathogens such as RSV, influenza, adenoviruses, SARS-CoV-2 and Mycoplasma pneumoniae, among others.

  • Mycoplasma pneumoniae causes an acute respiratory infection most commonly affecting young adults and school-aged children, with a case-fatality rate of less than 0.1%. The disease spreads between people through inhalation of droplets that contain the bacteria, most outbreaks occurring in crowded places including schools, residential halls, long-term care facilities, and hospitals. Symptoms of M. pneumoniae are shared by, and therefore easily confused with other respiratory pathogens that usually co-circulate during peak times, including influenza, COVID-19, and RSV. There is no vaccine for M. pneumoniae, but the disease can usually be effectively treated with antibiotics.
  • COVID-19 activity seems to be stabilising or even decreasing slightly in some countries such as the US, the UK and Canada, but rising in others such as Australia and New Zealand.
  • When interpreting COVID-19 figures it is important to bear in mind that global prevalence is heavily biased towards countries and regions with stronger surveillance, which may tend to show higher burdens of disease than others. Moreover, microbiological sequencing varies significantly across countries, submission of data may be delayed, and suspected new variants may be preferentially sequenced compared to “older” well-known variants - these all factors that may introduce additional bias.

Links to selected articles of interest:

  • A study linking viral infection with reduced levels of serotonin, a neurotransmitter involved in learning, memory, and mood, has proposed a new potential mechanism underlying post–COVID-19 condition (PCC), also known as long COVID, a condition involving symptoms such as fatigue, memory loss, and cognitive impairment. A viral reservoir in the gut appears to trigger inflammation that decreases intestinal absorption of tryptophan, serotonin’s precursor molecule. These findings raise hope for a clinically useful biomarker for PCC. https://www.eurekalert.org/news-releases/1004844
  • The results of a study that followed over half a million adults in Sweden suggest a strong association between covid-19 vaccination before infection and reduced risk of receiving a diagnosis of PCC (post-COVID-19 condition, also known as long Covid): https://www.bmj.com/content/383/bmj-2023-076990
  • The US Centers for Disease Control and Prevention (CDC) have announced that a new pilot program will monitor for respiratory viruses such as influenza and RSV in addition to SARS-CoV-2 as part of the Traveler-based Genomic Surveillance (TGS) program. The TGS program began in 2021 to detect new SARS-CoV-2 genomic variants. Three sources are used: self-collected nasal swabs from travellers at participating airports, wastewater from these airports, and wastewater from aircrafts. According to the CDC, the TGS program led to detection of Omicron variants weeks before they were reported globally. https://www.cdc.gov/media/releases/2023/s1107-testing-respiratory-viruses.html


In case this interests you or you know someone who might be interested, there is a call for tender from EASA for the Horizon Europe Project, which is about research on aviation safety and sustainability issues to prepare future standards and regulations, more specifically new health safety measures in aircraft: https://ec.europa.eu/info/funding-tenders/opportunities/portal/screen/opportunities/tender-details/2946378e-e34f-41de-a270-87dff3baae50-CN

Dr Rui Pombal

IATA Medical Advisor