By Joyce Ojanji
For several years mpox has been increasingly diverging from its previous distribution in Central and West Africa to cause outbreaks globally. Changes to the viral genome mean it is better able to spread, becoming a growing threat to public health.
Since the beginning of 2022, mpox cases have been reported to the World Health Organization (WHO), from 116 member states across all the six WHO regions. As of 31st may 2024. A total of 97745 laboratory confirmed cases and 535 probable cases, including 203 deaths, have reported to the WHO.
At least 12 African countries, including previously unaffected nations like Burundi, Kenya, Rwanda, and Uganda, have reported mpox outbreaks. So far in 2024, these countries have confirmed 2,863 cases and 517 deaths, primarily in the Democratic Republic of the Congo (DRC).
Countries in Africa and beyond are making effort to ensure that they curb the spread of this disease. In this regard, New Zealand has provisionally issued consent to the sale, supply or use of the new vaccine known as JYNNEOS.
The New Zealand government says it has set up a national-level Incident Management Team to co-ordinate the public health response, and a next step is for the National Immunisation Technical Advisory Group to promptly review which groups are at greatest risk and most likely to benefit from the vaccine.
In people vaccinated before exposure to the mpox virus, JYNNEOS is believed to provide solid protection. Clinical trials indicated that the vaccine generates a strong immune response, with the immune markers suggesting it offers good protection against both mpox and smallpox (as the vaccine is primarily derived from a modified vaccinia virus, related to both).
JYNNEOS can also be used as post-exposure prophylaxis (PEP). When administered within four days of exposure, it is expected to prevent the onset of disease. If given between four to 14 days after exposure, the vaccine may reduce the severity of symptoms, though it might not prevent the disease entirely.
During the 2022 mpox outbreak, studies indicated that people who received one dose of the JYNNEOS vaccine were around 30–50% less likely to get infected compared to unvaccinated individuals. With two doses, effectiveness improved, with early studies suggesting that fully vaccinated individuals (with both doses) could have up to *66–85% effectiveness in preventing infection.
Optimal protection is expected about two weeks after the second dose of the JYNNEOS vaccine, which is given as a two-dose series (the second dose administered 28 days after the first).
According to Dr Edwin Reynolds, Medical Advisor, Immunisation Advisory Centre, The access and advertising of the unregistered mpox vaccine product has been quite limiting since 2023 using the specific provision of Section 29. They were unable to advertise vaccine clinics and every vaccine administration required a doctor’s consultation with the resulting prescription for administration. So this announcement eliminates the need for these restrictions.
‘’The mpox vaccine is being delivered to the most at-risk via sexual health clinics but this announcement means other providers will be able to access the vaccine for their patients.Delivery of the vaccine through sexual health clinics to the gay and bisexual community has been a very effective public health tool to prevent ongoing transmission of this virus in the NZ setting,” he added.
“It is positive to see Government and health authorities taking a proactive approach to managing the threat posed by mpox within Aotearoa New Zealand. The recent media release mentions several valuable steps, including a mechanism to coordinate the response, improved communications, and increased vaccine access. It will be important to monitor the response to this epidemic and ensure that measures such as vaccination are reaching those who are at highest risk of mpox infection,’’ Professor Michael Baker, Public Health, University of Otago noted.
In Africa, the Africa CDC has signed a partnership agreement with the European Commission’s Health Emergency Preparedness and Response Authority (HERA) and Bavarian Nordic to provide over 215,000 doses of the MVA-BN® vaccine—the only FDA and EMA-approved Mpox vaccine. Africa CDC will oversee the equitable distribution of these vaccines, prioritizing local needs across the affected Member States.
