7th Cholera Pandemic Continues

The World Health Organization (WHO) today reported that the global cholera situation has further deteriorated, with at least 18 countries reporting cholera cases.

On February 11, 2023, the WHO assessed the health risk from these cholera outbreaks as very high globally.

The world is facing an acute upsurge of the 7th cholera pandemic characterized by the number, size, and concurrence of multiple outbreaks, the spread to areas free of cholera for decades, and alarming high mortality rates, says the WHO.

The risk of cholera in people increases with decreasing access to clean water and sanitation.

Moreover, there is a lack of vaccines available for this vaccine-preventable disease.

In 2021, 23 countries reported cholera outbreaks, mainly in the WHO Regions of Africa and the Eastern Mediterranean.

This trend continued into 2022 as 30 countries reported cholera cases or outbreaks.

Among those, 14 had not reported cholera in 2021, including non-endemic countries (Lebanon and Syria) or countries that had not reported cases over three years (Haiti and the Dominican Republic).

Cholera is an acute diarrheal infection. It is characterized by extreme watery diarrhea and potentially fatal dehydration when severe. 

It is caused by ingesting food or water contaminated with the bacterium Vibrio cholerae. It has a short incubation period of twelve hours and five days. 

The mortality associated with those outbreaks is of particular concern as many countries reported higher case-fatality ratios (CFR) than in previous years.

The average cholera CFR reported globally in 2021 was 1.9% (2.9% in Africa), a significant increase above acceptable (<1%) and the highest recorded in over a decade.

And preliminary data suggests a similar trend for 2022 and 2023.  

Previous studies estimate 2.9 million cholera cases and 95,000 deaths occur annually. 

The last WHO Disease Outbreak News highlighted the potential drivers of the outbreaks and challenges impacting response activities.

Nearly all cholera cases reported in the U.S. are acquired during international travel. Therefore, on December 5, 2022, the U.S. CDC stated clinicians should be prepared to treat cholera cases in returning travelers.

While there are approved oral cholera vaccines (OCV), access in 2023 is very constrained.

In October 2022, the International Coordinating Group made the unprecedented decision to temporarily suspend the second dose of OCV for outbreak response due to the global vaccine shortage, which continues in 2023.

Although effective, the single-dose strategy will result in a shortened duration of vaccine-induced immunity, particularly in children under five years of age, leaving the populations vulnerable to cholera the following year, says the WHO.

In the U.S., the Food and Drug Administration-approved VaxChora® OCV is unavailable as of February 12, 2023. However, the manufacturer recently stated VaxChora might become available in the U.S. in mid-2023.

Other cholera outbreak news is posted at Vax-Before-Travel.com/Cholera.