Hot Topics in IPC: Marburg Virus, Human Cases of Bird Flu, and COVID-19 Origin

Saskia v. Popescu, PhD, MPH, MA, CIC

It’s been a wild week in infection prevention, epidemiology, and infectious diseases – but hasn’t that become the new trend? The new norm for us is slowly becoming the “How best do I drink from the firehose?”

Marburg Equatorial New Guinea

It’s been nearly a month since the Ministry of Health and Social Welfare of Equatorial Guinea reported deaths related to a suspected hemorrhagic fever. Five days later, it was confirmed to be the Marburg virus. According to the World Health Organization (WHO), in their latest update on February 21, 2023, there have been 9 cases, including 1 confirmed death. One case occurred in a health care facility; the other 8 were identified in the community. There are 30+ people being monitored as contacts, and no cases involve health care workers. Marburg is worrisome–it has a case-fatality rate of 88% and an incubation period ranging from 2-21 days and requires the kind of PPE we used for Ebola in 2014/2016. As the WHO noted, “Marburg spreads through human-to-human transmission via direct contact (through broken skin or mucous membranes) with the blood, secretions, organs, or other bodily fluids of infected people, and with surfaces and materials (eg bedding, clothing) contaminated with these fluids. Health care workers have previously been infected while treating patients with suspected or confirmed [Marburg Virus Disease]. Burial ceremonies that involve direct contact with the body of the deceased can also contribute to the transmission of Marburg.” Here are some helpful resources from the CDC and a reminder of what the levels of personal protective equipment and infection prevention response look like from Ebola.

H5N1 on the Rise and Human Cases

Avian influenza has been on the rise lately, and the highly-pathogenic kind is spreading like wildfire across the globe, with concerning transmission among mammals. Devastating to bird and mammal populations, it thankfully does not spread efficiently in humans. So why is everyone worried? It normally doesn’t spread well between mammals either, but cases in Spain within a mink farm changed this and were indicative of concerning genetic changes in the virus that allowed for sustained spread. More recently, H5N1 was responsible for 2 human infections in Cambodia, resulting in the death of a young girl. The Clade that caused these, though, is the one we’ve seen spread throughout the region for many years and is not that responsible for mammalian cases. (This is a good thing.) Nonetheless, though, it serves as a reminder of how interconnected our world is and that human, animal, and plant health all impact each other. One Health, eh?

COVID-19 Origin

Is this something that impacts infection prevention and control work? Probably not, but one thing I’ve learned over the years is that the scope of what we do and face is only broadening…and, frankly, awareness of infectious disease events and issues is essential for situational awareness. The origin of COVID-19 is a complex topic that will likely not be settled with the kind of certainty many individuals want. Recently, the US Department of Energy (DOE) announced it had changed its standing on the virus's origin, citing a stronger belief in laboratory origin (lab leak or accident) rather than zoonotic spillover. It’s important to note that many scientific findings have supported zoonotic spillover, and the DOE’s use of unspecified intelligence makes it hard to discern where the shift came from. The issue is that this topic has become increasingly partisan, and ultimately, one country deciding the origin of a virus that caused a pandemic is open to bias. This is complicated and very politically charged. My 2 cents is that focus on origin is important but distracts from the larger issue–the US response to COVID-19 was woefully inadequate, which is the real thing we need to address.

In Case You Have Time to Read an Article

No One Really Knows How Much COVID Is Silently Spreading … Again– By Katherine J. Wu, PhD. “More immunity and relaxed behavior add up to a new COVID mystery: How common is symptomless spread now?”