(Page 41) Post-acute infection consequences
Many infectious diseases have significant persisting post-acute infection consequences (Choutka et al 2022). Some of these consequences present soon after infection, such as the Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) type illnesses after Crimean Congo haemorrhagic fever (Ambikan et al 2023), SARS-CoV-1 infection (Li et al 2023), Ebola (Wohl et al 2022), Q-fever, dengue-fever and COVID-19 (Choutka et al 2022). Other health consequences have a delay before manifesting, such as human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV AIDS) (WHO 2022c), cancers caused by the human papillomaviruses (National Institutes of Health National Cancer Institute 2023) and post-polio syndrome (Choutka et al 2022).
Research on past and current pandemics (such as the Black Death, the 1918 influenza pandemic and COVID-19) has shown pandemics can cause significant and long-lasting population health consequences (DeWitte and Wissler 2018; van Doren and Sattenspiel 2021; Kelmelis and DeWitte 2021; van Doren and Kelmelis 2023; Wissler 2021; Saglanmak et al 2011; Noymer and Garenne 2000; van Doren and Brown, 2023). The full consequences of COVID-19 are not fully understood, but personal and societal impacts arising from persisting symptoms, grouped under various terms, such as long COVID, post-COVID condition and post-acute sequelae of COVID-19 (PASC), are significant (Callard and Perego 2021; Choutka et al 2022). There is also increasing evidence suggesting that COVID-19 causes neuropathological changes that could develop into neurological disorders later in life (Kim et al 2023). In addition to consequences triggered by the infection itself, there can be long-term health consequences arising from disease treatments (Vasilevskis et al 2010) and vaccinations (Tondo et al 2022).
As with the acute effects of a disease, different risks of post-infection consequences borne by different groups will exacerbate existing inequities. For example, foetuses may suffer brain damage causing permanent cognitive impairment as was the case for the Zika virus (Jash and Sharma 2022), and women appear to have a higher risk of ME/CFS-type illnesses (Clayton 2015).
Each re-infection may also risk post-infection consequences, as appears to be the case with COVID-19 (Bowe et al 2022; Kuang et al 2023). People who are repeatedly infected, as healthcare workers, people living in large family groups, and unvaccinated children attending school are likely to be, will have an accumulating lifetime risk of post-infection consequences.
It will be very rare for a pandemic disease to result only in short-term health impacts. Many of the long-term consequences of infections majorly impact quality of life and productivity and do not yet have diagnostic tests or effective treatments. They have been understudied, and the health workforce is generally poorly informed about them (Choutka et al 2022).
Differences in how people disabled by an infection or a post-infection chronic illness are supported compared with people disabled by an accident creates and exacerbates inequities (Cameron 2023; Kia Piki Ake - Welfare Expert Advisory Group 2019). An essential worker may have difficulty proving that they have been disabled by an infection contracted at work, particularly when the disease has become widespread in the community (Fisher 2022). A family member who contracts a disease from an essential worker and then goes on to be disabled is no less deserving of support but would not meet a criterion of harm sustained while at work. Aside from the equity issues, inadequate support provided to people harmed by infections and a lack of effective treatments may impact on the willingness of essential workers to put themselves at risk during a pandemic.
