By Michael Gwarisa
Following indications of Global Shortages of the Oral Cholera Vaccine (OCV), the International Coordinating Group (ICG), the body which manages emergency supplies of vaccines announced a temporary suspension of the standard two-dose vaccination regimen in cholera outbreak response campaigns, using instead a single-dose approach.
Despite fears from countries currently battling Cholera, the one-dose strategy has proven to be effective in responding to outbreaks, even though evidence on the exact duration of protection is limited, and protection appears to be much lower in children. With a two-dose regimen, when the second dose is administrated within 6 months of the first, immunity against infection lasts for 3 years
Speaking in an interview with HealthTimes, Professor Charles Shey Wiysonge, Team Lead, Vaccine-Preventable Diseases World Health Organization Regional Office for Africa said the one-dose strategy has proven to be effective in responding to outbreaks, even though evidence on the exact duration of protection is limited.
The benefit of supplying one dose still outweighs no doses: although the temporary interruption of the two-dose strategy will lead to a reduction and shortening of immunity, this decision will allow more people to be vaccinated and provide them protection in the near term, should the global cholera situation continue deteriorating,” said Professor Wiysonge.
Zambia launched its vaccination campaign in January targeting 1.5 million people, including children, health workers and people at high risk of infection in the worst affected areas. In Zimbabwe, the government applied for Oral Cholera Vaccines and was awarded 2.3 million doses from what was requested.
“But vaccination is not a silver bullet and will not solve the cholera problem the continent is experiencing. We need to focus on several things including early detection and quick response to contain outbreaks. A multi-sectoral approach to prevent cholera reoccurrence, which includes an emphasis on water, hygiene and sanitation, and an effective mechanism of coordination for technical support, advocacy, resource mobilization and partnership at local and global levels.”
He added that vaccine shortages of Oral Cholera Vaccines were not peculiar to Africa but rather a global challenge.
“The current supply of cholera vaccines is extremely limited. Its use for emergency response is coordinated by the ICG which manages the global stockpile of oral cholera vaccines, Multiple countries are responding to cholera outbreaks with OCV. These include the Democratic Republic of Congo (DRC), Zambia, and Zimbabwe all completed recent campaigns. Countries are evaluating the epidemiology of the outbreak and determining whether to conduct OCV campaigns in hotspots.”
Meanwhile, eight African countries are in acute crisis with at least 16 reporting cases. Even though uptake in many countries has been high, there have been challenges along the way.
“There are always challenges in any vaccination campaign. Often people say that there was not enough information about the campaign, others have competing obligations. Additionally, there is always the fear of vaccine side effects and that it may make one sick. In any vaccination campaign, community engagement is key before and during the campaign to ensure community members are educated and feel comfortable with the vaccine, “added Prof Wiysonge.
In Zimbabwe, vaccination has been progressing well despite the global shortages as well as rise in disinformation and misinformation. Deputy Cholera Incident Manager in the Ministry of Health and Child Care, Dr Stephen Karimu said
“So in terms of supply of the OCV, there is a shortage on the world market. It’s not a vaccine that is plentiful, right? So there is rationalization now. You might be aware that most countries are hit by cholera, so demand is high there. Supply is not meeting demand. So we are giving one dose because of inadequate supplies on the global market,” said Dr Karimu.
Meanwhile, the Africa Centre for Diseases Control (Africa CDC) has reiterated the need for home-grown solutions to the unending vaccine inequalities and shortages.
Speaking the African Union convention, Dr John Kaseya, though his micro-blogging site said,” Ensuring African vaccines get international regulatory backing is key to vaccine independence. African CDC is working with International Vaccine institute to facilitate the technology transfer to make this happen.”
The current supply of cholera vaccines is extremely limited. Its use for emergency response is coordinated by the ICG which manages the global stockpile of oral cholera vaccines. Of the total 36 million doses forecast to be produced in 2022, 24 million have already been shipped for preventive (17%) and reactive (83%) campaigns and an additional 8 million doses were approved by the ICG for the second round for emergency vaccination in 4 countries, illustrating the dire shortage of the vaccine.
